Department of Health and Human Services 

OFFICE OF 

INSPECTOR GENERAL 

JUNE GIBBS BROWN 

Inspector General 

OCTOBER 2000 

OEI 06-99-00090 

HYPERBARIC OXYGEN THERAPY 

Its Use and Appropriateness 
OFFICE OF INSPECTOR GENERAL 

The mission of the Office of Inspector General (OIG), as mandated by Public Law 95-452, is to 

protect the integrity of the Department of Health and Human Services programs as well as the 

health and welfare of beneficiaries served by them. This statutory mission is carried out through a 

nationwide program of audits, investigations, inspections, sanctions, and fraud alerts. The 

Inspector General informs the Secretary of program and management problems and recommends 

legislative, regulatory, and operational approaches to correct them. 

Office of Evaluation and Inspections 

The Office of Evaluation and Inspections (OEI) is one of several components of the Office of 

Inspector General. It conducts short-term management and program evaluations (called 

inspections) that focus on issues of concern to the Department, the Congress, and the public. The 

inspection reports provide findings and recommendations on the efficiency, vulnerability, and 

effectiveness of departmental programs. 

OEI's Region VI prepared this report under the direction of Chester B. Slaughter, Regional 

Inspector General and Judith V. Tyler, Deputy Regional Inspector General. 

Principal OEI staff included: 

DALLAS 

Amy Beeson 

Kevin Golladay 

J’nette Oshitoye 

HEADQUARTERS 

Jennifer Antico 

Brian Ritchie 

Barbara Tedesco 

To obtain copies of this report, please call the Dallas Regional Office at 214-767-3310. 

Reports are also available on the World Wide Web at our home page address: 

http://www.dhhs.gov/progorg/oei 
EXECUTIVE SUMMARY 

PURPOSE 

To describe the extent and appropriateness of hyperbaric oxygen treatment (HBO2) 

provided to Medicare beneficiaries. 

BACKGROUND 

HBO2 involves giving a patient high concentrations of oxygen within a pressurized 

chamber. Originally developed for the treatment of decompression sickness, HBO2 is 

primarily an adjunctive treatment for the management of select non-healing wounds. To 

evaluate the extent and appropriateness of HBO2 we reviewed pertinent Health Care 

Financing Administration (HCFA) policies and published research, met with several 

interest groups representing hyperbaric physicians, analyzed Medicare claims data for 

HBO2 between 1995 and 1998, conducted medical review of HBO2 claims for a stratified 

sample of beneficiaries, surveyed a sample of facilities with HBO2 chambers, and surveyed 

contractor medical directors. 

FINDINGS 

$14.2 Million (of the $49.9 million allowed charges for outpatient hospitals and 

physicians) Was Paid in Error for Hyperbaric Treatments 

Nearly 32 percent of beneficiaries received treatments for either non-covered conditions 

(22.4 percent, $10.5 million) or documentation did not adequately support HBO2 

treatments (9.2 percent, $3.7 million). While medical review would be necessary to 

identify most of these overpayments, some could have been detected had contractors 

utilized appropriate computer claims processing diagnoses edits. 

An Additional $4.9 Million Was Paid for Treatments Deemed to Be Excessive 

Eleven percent of beneficiaries were treated for appropriate indications, but received more 

treatments than were considered medically necessary by our physician reviewers. The 

excessive treatments represent $4.9 million paid for potentially ineffective procedures. 

Lack of Testing and Treatment Monitoring Raise Quality of Care Concerns 

Of the 68 percent of beneficiaries treated for covered conditions, 37 percent received 

questionable quality care with respect to either lack of appropriate testing prior to initiation 

of treatment or insufficient progress documented to justify continuation of therapy. The 

treatments with suspect quality account for as much as $11.1 million in payments. 

Additionally, our medical reviewers determined that more than 25 percent of beneficiaries 

had no documented physician oversight of their treatments; and almost twice 

HBO2: Its Use and Appropriateness i OEI 06-99-00090 
that many (44 percent) did not have a physician in attendance at their treatments. While 

attendance is not specifically required, our medical review showed a correlation between 

certain quality of care factors and physician attendance. 

The Health Care Financing Administration’s Guidance Is Limited 

The guidance provided by the Health Care Financing Administration (HCFA) has been 

limited only to specifying covered disease conditions. As a result, carriers and 

intermediaries have varied payment guidelines (e.g., physician attendance, credentialing 

requirements), medical review procedures (i.e., use of diagnosis edits and post-payment 

review policies), and documentation requirements. While practice protocols and standards 

of care have been proposed by the HBO2 industry, HCFA has not incorporated either into 

its coverage policy. 

Questions Over Appropriate Usage Along With a Potential for Expansion Increase 

the Risks Related to the Vulnerabilities Found 

Although HBO2 has been a covered treatment option for many years, some questions still 

remain about its appropriate place in the context of wound-care. A recent assessment, 

performed in 1999 by the Blue Cross and Blue Shield Association, showed that some of the 

Medicare-covered indications do not have sufficient published evidence to determine that 

HBO2 is beneficial; however, this same study also documented evidence to support two 

conditions not specifically covered (chronic non-healing wounds and thermal burns). 

Questions of appropriate usage are magnified by the expense of the treatment. Total costs 

for outpatient HBO2 treatments and physician supervision average between $7,000 and 

$12,000 with extremes exceeding $100,000. Currently, the highest rates of use are in 

Colorado and the southern coastal states of Texas, Louisiana, and Mississippi. If other 

states had the same utilization as Texas, total reimbursement would increase five-fold. 

While this expansion is possible, recent and proposed changes or clarifications in Medicare 

coverage (e.g., non-coverage of preparation for a graft not previously compromised) and 

reimbursement (outpatient prospective payment and physician fee schedule reductions) may 

curtail expansion. 

RECOMMENDATIONS 

To address concerns raised in this report, we recommend that the Health Care Financing 

Administration: 

! Initiate its national coverage decision process for HBO2. 

! Improve policy guidance ( e.g., practice guidelines and physician attendance 

policy). 

! Improve oversight by requiring contractors to initiate edits and consistent 

medical review procedures, and by exploring the establishment of a registry 

of facilities and/or physicians providing HBO2. 

HBO2: Its Use and Appropriateness ii OEI 06-99-00090 
AGENCY COMMENTS 

The HCFA generally concurs with our recommendations, and reports several on-going 

efforts to address concerns raised in this report (e.g., reviewing coverage policy and 

alerting carriers to vulnerabilities associated with this procedure). 

HBO2: Its Use and Appropriateness iii OEI 06-99-00090 
TABLE OF CONTENTS 

PAGE

EXECUTIVE SUMMARY i

INTRODUCTION 1

FINDINGS 6

Questions persist concerning the appropriate usage of HBO2 ..................... 6

Potential for expansion exists within the hyperbaric industry ...................... 8

$14.2 million was paid in error for hyperbaric treatments ........................ 9

An additional $4.9 million was paid for excessive treatments .................... 11

Our review of HBO2 raised several quality of care concerns ..................... 11

Some carriers and intermediaries do not apply edits and appropriate 

medical review standards ............................................... 13

HCFA’s guidance for this procedure is limited ............................... 15

Recent and impending regulatory changes may affect growth .................... 19

RECOMMENDATIONS 20

ENDNOTES 22

APPENDICES 

A: Cellular and biochemical benefits of hyperbaric oxygen ..................... A-1

B: Section 35-10 of the Coverage Instruction Manual ........................ B-1

C: Discussion of covered indications by Florida BC/BS ....................... C-1

D: Appropriateness of Treatment ........................................ D-1

E: Accepted usage of HBO2 by HCFA and Interest groups .................... E-1

F: Comparison of ICD-9 Interpretations .................................... F-1

G: Key Questions from the Medical Review Protocol ......................... G-1

H: Agency Comments ................................................ H-1
INTRODUCTION 

PURPOSE 

To describe the extent and appropriateness of hyperbaric oxygen treatment (HBO2) 

provided to Medicare beneficiaries. 

BACKGROUND 

Hyperbaric Oxygen Therapy 

Hyperbaric oxygen therapy (HBO2) provides a therapeutic dose of oxygen by creating a 

pressurized environment in which patients intermittently breathe 100 percent oxygen.1 

This procedure was originally developed for the treatment of decompression sickness; but 

the primary usage in the United States currently is for wound care. Although the 

mechanisms are not firmly established in scientific literature, most agree that hyperbaric 

oxygen therapy serves four primary functions. First, it increases the concentration of 

dissolved oxygen in the blood, which enhances perfusion. Second, it stimulates the 

formation of a collagen matrix so that new blood vessels may develop. Third, it replaces 

inert gas in the bloodstream with oxygen, which is then metabolized by the body; and 

finally, it works as a bactericide. The proposed biological and chemical benefits of HBO2 

are further described in Appendix A. 

The HCFA has established fourteen conditions in its Coverage Instruction Manual (CIM) 

section 35-10 for which hyperbaric therapy is reimbursable. For additional information on 

the fourteen conditions, see Appendices B and C. The indications include: 

(1) Acute carbon monoxide intoxication

(2) Decompression illness

(3) Gas embolism

(4) Gas gangrene

(5) Acute traumatic peripheral ischemia 

(6) Crush injuries

(7) Progressive necrotizing infections

(8) Acute peripheral arterial insufficiency

(9) Preparation and preservation of compromised skin grafts

(10) Chronic refractory osteomyelitis

(11) Osteoradionecrosis (ORN)

(12) Soft tissue radionecrosis (STRN)

(13) Cyanide poisoning

(14) Actinomycosis

The standard definition of hyperbaric oxygen therapy is intermittent 100% oxygen 

breathing at greater than one absolute atmospheric pressure (1 ATA); however, the 

HBO2: Its Use and Appropriateness 1 OEI-06-99-00090 
 Undersea and Hyperbaric Medical Society (UHMS) reports that the pressurization should 

be 1.4 ATA or higher.2 Each treatment (or “dive”, an analogy relating to the 

pressurization) is generally between 60 and 120 minutes in length3 ; and each patient will 

generally receive between 10 and 60 total sessions throughout the course of therapy. 

The delivery system for this therapy may be in the form of a monoplace or a multiplace 

chamber. A monoplace chamber is designed for a single patient to lie in the supine 

position. The entire chamber is filled with oxygen for the duration of the treatment. The 

larger multiplace system (See Figure 1) is designed to accommodate between two and 

twelve patients comfortably and in a variety of positions. It often has an additional 

compartment for attendants to go in and out of the chamber without interrupting 

treatments; however, in some cases the attendant may spend the duration of the treatment 

with a patient. In this type of chamber, oxygen is administered through a mask or head tent 

during the procedure. Topical and extremity hyperbaric units describe a third class of 

chamber, but this class is not considered an acceptable substitute for the full body chamber 

and is not covered by Medicare. 

Figure 1 

The literature states that the most common side effects are middle ear barotrauma and 

claustrophobia, which occur in 2 percent of treatments. Other mild side effects include 

sinus squeeze, serous otitis, reversible progressive myopia, and in about 1 per 10,000 

treatments, pulmonary and neurologic manifestations of oxygen poisoning.4 Additional 

concerns have to do with safety related to the risk of fire created by the use of compressed 

oxygen. 

Medicare Payments 

Medicare allowed charges of approximately $76 million dollars ($47 million paid) for 

HBO2 in 1998 for 15,687 beneficiaries. Outpatient reimbursement was $35 million for 

6,734 beneficiaries, physicians received $18 million for 7,282 beneficiaries, approximately 

HBO2: Its Use and Appropriateness 2 OEI-06-99-00090 
$19 million was associated with a hospital stay for 8,916 beneficiaries, and nearly $5

million was allowed as part of a skilled nursing facility stay for 1,408 beneficiaries.5

HBO2 treatments generally involve a facility charge and often a charge by a physician for

supervision. Procedure code 99183 is billed for physician supervision and revenue center

413 includes facility charges for HBO2. Facility reimbursement is typically included as part

of the prospective payment’s diagnosis related group (DRG) payment if provided during an

inpatient 

hospital stay or cost-based if provided by an outpatient department. Physician

reimbursement is based on a fee schedule and was approximately $140 in 1998. In

contrast, cost-based outpatient reimbursement varies considerably from hospital to hospital. 

Cost-based reimbursement is currently being replaced with a prospective payment system

for these services.

METHODOLOGY 

To evaluate the extent and appropriateness of HBO2 we reviewed pertinent HCFA 

policies, met with several interest groups representing hyperbaric physicians, analyzed four 

years of Medicare payments, conducted medical review on a stratified sample of 

beneficiaries, surveyed a sample of facilities with HBO2 chambers, and surveyed contractor 

medical directors. 

Medicare Payment Data 

We identified all Medicare beneficiaries with hyperbaric treatments paid by Medicare 

between 1995 and 1998. Identification of a hyperbaric procedure was based on the 

American Medical Association’s (AMA) CPT code 99183 (hyperbaric oxygen treatment) 

or facility revenue center code 413 (hyperbaric). We then extracted all payments 

maintained in HCFA’s National Claims History (NCH), whether paid by a carrier 

(physician claims) or an intermediary (hospital inpatient, hospital outpatient, or skilled 

nursing facility claims). This data was then utilized in sample selection, provider profiling, 

and trending (among states and over years). 

Sample Selection 

Sampling was done by beneficiary with stratification based on overall payments for the 

entire duration of HBO2 treatment. Any beneficiary having HBO2 payments during a one 

year period (July 1, 1997 through July 1, 1998) represented the universe. Stratification 

was as follows: 

HBO2: Its Use and Appropriateness 3 OEI-06-99-00090 
Sample Stratification 

Strata (Allowed Charges for HBO2 

over entire course of treatment) 

Population Sample 

Size 

$100 to $5,000 4962 95 

$5,001 to $10,000 2165 95 

$10,001 to $20,000 1661 95 

$20,001 to $100,000 622 95 

Over $100,000 15 15 

Beneficiaries with Physician or 

Outpatient HBO2 Payments 

9,425 395* 

*Sample reduced to 378 because of facility non-response. 

We limited strata payment calculations to outpatient facility payments and physician 

payments. Hospital inpatient services were excluded because reimbursement is based on a 

prospective payment system. Since the receipt of HBO2 while in the hospital was unlikely 

to affect the diagnosis related group (DRG) or admission, no overpayments to the facility 

would result from unnecessary treatment. 

Medical Record Request 

For each beneficiary sampled, the complete patient’s medical history was requested from 

the point HBO2 treatments began to the point they stopped. In most cases, records were 

provided by the hospital where services were provided; however, in some cases, the 

physician provided additional information. We requested: 

1. History and physical, 

2. Substantiation of diagnosis for hyperbarics (e.g. lab work; photographs; 

operative notes; initial consult for hyperbarics; and, physician’s evaluations), 

3. Substantiation of hyperbaric treatment (e.g. treatment logs; physician 

progress notes; and, technician progress notes), 

4. Substantiation of medical necessity for hyperbarics (e.g. progress notes and 

evaluations), and 

5. Discharge summary. 

Medical Record Review Process 

Because of the specialized nature of hyperbarics and the need for reviewers with 

knowledge and expertise in hyperbarics, we contracted with four physicians who currently 

practice in the field and are experienced in wound management. These physicians are 

involved in a variety of relevant activities such as the following: 

HBO2: Its Use and Appropriateness 4 OEI-06-99-00090 
- Used as a medical reviewer for the local Medicare contractor, 

- Contribute to the medical literature through journal articles, 

- Actively involved in HBO2 associations (e.g., Undersea Hyperbaric Oxygen 

Society (UHMS)). 

We developed a detailed medical review protocol which we refined with the assistance of 

the physician reviewers. The review protocol assessed (1) medical necessity and 

appropriateness, (2) adherence to Medicare coverage policy, (3) utilization patterns, (4) 

documentation, and (5) outcome. All reviews and medical appropriateness decisions were 

made by the medical reviewers. 

Contractor Medical Director Survey 

A brief survey was sent to each carrier and intermediary medical director asking questions 

about local HBO2 payment experience and policy (68 of the 74 medical directors 

responded). Individual perceptions of the efficacy of HBO2 were also obtained. 

Facility Survey 

Each facility treating beneficiaries in our sample was identified and sent a survey along with 

the request for medical records (211 of the 217 facilities responded). Facilities were asked 

to provide information about the type of chamber used and the qualifications of the staff. 

Statistical Analysis 

Chi-square and Cochran Mantel-Haenszel statistics, percentage estimates and 

corresponding 95 percent confidence intervals for key medical review data were computed 

using the computer program Sudaan. Sudaan is a statistical analysis program with 

appropriate standard statistical formulas for calculating correct standard errors for complex 

sampling using stratification. 

Non-Response Analysis. A non-response analysis was conducted for the seventeen 

facilities that failed to provide records for the medical review. Thirteen of the facilities 

(76%) did complete the facility survey describing practices and characteristics of the 

hyperbaric department. No significant differences were found between the responding and 

non-responding facilities with the exception that non-responding facilities were more likely 

to use a multiplace chamber (p=.04) and employ at least one full-time physician (p=.06). 

This inspection was conducted in accordance with the Quality Standards for Inspections Issued by 

the President’s Council on Integrity and Efficiency. 

HBO2: Its Use and Appropriateness 5 OEI-06-99-00090 
FINDINGS 

Questions persist concerning the appropriate usage of 

hyperbaric oxygen therapy 

For years, hyperbaric oxygen therapy has been considered a controversial procedure 

because of a lack of rigorous scientific evidence demonstrating the efficacy of its use for 

many of the conditions Medicare covers. This was the conclusion, in 1995, by the 

Department of Health and Human Services’ Agency for Healthcare Research and Quality 

(AHRQ).6 Their review criticized available research studies for having poor study 

design(s), non-standardized protocols and poor patient selection” which caused “equivocal 

and conflicting conclusions concerning [HBO2's] efficacy.” In response to these criticisms, 

HBO2 interest groups countered that small sample size and lack of control groups were 

research problems inherent to the conditions being treated. Consequently, AHRQ’s review 

discounted much of the most compelling evidence as a result of methodological issues. 

Since AHRQ’s review, the body of research supporting HBO2 has continued to grow, with 

some studies achieving adequate research standards (i.e., appropriate control groups, 

adequate sample size, an appropriately defined and homogeneous patient population, a well 

described treatment regimen, valid health outcome measures, and publication of results in a 

full length, peer-reviewed journal article). While the research has yet to fully prove the 

efficacy of all the currently approved conditions, a recent (1999) review by the Blue Cross 

and Blue Shield Association’s Technology Evaluation Center for a select number of 

medical conditions found adequate scientific evidence to support acute traumatic peripheral 

ischemias, clostridial myonecrosis, and a few conditions not specifically covered by 

Medicare, such as chronic non-healing wounds7 and burns.8 Although this review found 

evidence of efficacy for these conditions, adequate evidence was not found to validate the 

efficacy of several conditions Medicare currently covers: compromised skin grafts, chronic 

refractory osteomyelitis, and necrotizing soft-tissue infections. The results support the 

claim that hyperbarics is a beneficial treatment; however, Medicare may not cover the 

appropriate conditions. Furthermore, hyperbarics may not be the most cost-effective 

treatment option for some patients and conditions. 

Carrier and intermediary medical directors support the use of HBO2, but vary in opinion on 

the extent of covered indications. While over half of all carrier and intermediary medical 

directors responding to our survey said hyperbaric therapy is beneficial for all of the 

currently covered conditions, one third still believe that hyperbaric coverage is too broad. 

Outside the United States, HBO2 is viewed with less conservatism. International medical 

communities cite as many as 20 classes of indications, relating to 66 specific conditions, for 

HBO2 (See Appendix E). This is considerably more than the 14 indications approved by 

the HCFA. 

HBO2: Its Use and Appropriateness 6 OEI-06-99-00090 
Hyperbarics is most commonly used to treat wound related problems 

The most commonly treated indications for Medicare beneficiaries are arterial insufficiency, 

effects of radiation and compromised skin grafts. The following figure (Figure 2) indicates 

the breakdown of primary treatment indications found in the medical review sample.

9 

Figure 2

CIM 35-10 Indications for Treatment

(% of beneficiaries) 

Acute Peripheral Arterial Insufficiency 20.9% 

Effects of Radiation (ORN and STRN) 15.1% 

Preparation & Preservation of Skin Grafts 15.0% 

Chronic Refractory Osteomyelitis 8.6% 

Progressive Necrotizing Infections 4.0% 

Gas Gangrene 1.3% 

Decompression Sickness 0.8% 

Carbon Monoxide Poisoning 0.6% 

Acute Traumatic Peripheral Ischemia 0.2% 

Non-covered primary indications10 33.5% 

Costs per individual are very high 

The number of beneficiaries actually receiving hyperbarics remains relatively small, but the 

costs per beneficiary can be very high. The average total allowed charge per treatment in 

1998 was approximately $405 ($140 for physician supervision and $265 for outpatient 

services). Coupled with the relatively high average number of treatments per individual 

(29), this results in an average allowed therapy cost of over $12,000 for a single patient. 

The top five percent of beneficiaries have considerably higher costs, ranging from $50,000 

to $325,000 per individual. The hyperbaric societies contend that although the procedure is 

relatively expensive and benefits a very small group of individuals, hyperbaric oxygen 

therapy is a cost-effective means to treat candidates with select wounds and a few lifethreatening medical conditions. The UHMS Committee Report (1996) states that "aside 

from clinical efficacy, HBO2 yields direct cost savings by successfully resolving a high 

percentage of difficult and expensive disorders, thereby minimizing prolonged 

hospitalization." 

Individual outcomes vary greatly 

Although our medical review did not attempt to independently evaluate the overall efficacy 

of HBO2, the benefits of hyperbarics, as evaluated by our medical review team, ranged 

from saving lives to no benefit at all. While a few are believed to have benefitted 

HBO2: Its Use and Appropriateness 7 OEI-06-99-00090 
to the extent that either life or limb was saved (0.7 percent), thirteen percent of 

beneficiaries showed no improvement of their medical condition after treatment with 

HBO2. The treatment may also be considered burdensome to the beneficiary, for they are 

financially responsible for at least 20 percent of the cost of therapy; and according to our 

review, 18 percent demonstrated side effects as a result of the HBO2.4 Furthermore, there 

is no way to determine if those who do benefit would have seen improvement without the 

treatment or with other aggressive wound care. However, to acknowledge the risks, costs 

and variable outcomes does not necessarily disparage this procedure. Hyperbaric therapy is 

generally reserved as a last resort, when other treatment options are exhausted. The 

population targeted is generally elderly and very ill. The average age of a hyperbaric 

Medicare patient is 70. At least 45 percent are diabetic; and almost 40 percent have some 

form of heart disease. It also appears that about 18 percent are deceased within two years 

after treatment. Hyperbarics is often an end of life procedure and may provide a reprieve 

from painful non-healing wounds; and in some cases, it is credited with saving lives. 

Potential for expansion exists within the hyperbaric industry 

Medicare Payments and Providers Steadily Increased From 1995 to 1998 

In 1998, allowed charges were approximately $76 million for 15,687 beneficiaries. 

Charges were distributed between physicians (24 percent), hospitals (70 percent), and

skilled nursing facilities (6 percent). Between 1995 and 1998, charges increased by 52

percent (not adjusting for inflation) while the total number of Medicare beneficiaries

treated increased by only 27 percent. (See 

Figure 3.) 

The increases in payments and

beneficiaries were outpaced by even Figure 3

larger increases in the number of

providers of HBO2 during this same

period. For example, the number of

hospitals billing outpatient HBO2

increased by 122 percent (from 232

facilities to 514), while the number of

physicians billing HBO2 procedures

increased 64 percent (from 642 to

1053). 

The increases in billing and providers of

HBO2 parallel overall growth in the

wound care market and reflect increased

access to affordable chambers. The

Florida-based American Academy

estimated that in 1998 the market for

hyperbaric chambers was $1.74 billion

and is expected to grow to 

HBO2: Its Use and Appropriateness 8 OEI-06-99-00090 
$2.57 billion by 2002.11 The dramatic rise in the wound care market has created an 

attractive opportunity for medical equipment suppliers who are making chambers available 

at costs of less than $100,000 or through lease arrangements. 

Utilization Varies Between Geographic Regions 

The highest rates of per capita use of HBO2 are in Colorado and the gulf states of Texas, 

Louisiana, and Mississippi. By far, Texas is the state with the highest number of treatments 

and total billing; total allowed charges were over $21 million in 1998, nearly three times the 

charges of any other state. The disproportionate use of HBO2 is most likely a result of 

geographic differences in exposure to hyperbarics in medical schools, professional 

environments, incidence of diabetes, and access to chambers. Since chambers were 

originally developed to treat decompression illness, it is not surprising that chambers would 

be located in coastal areas, particularly areas proximate to deep sea oil wells. As 

researchers discovered other uses for HBO2 (i.e., wound care), additional chambers were 

installed in those areas. While chambers can be found in most states, variation in billing for 

HBO2 between states and the limited numbers of chambers in many states suggests an 

opportunity for expansion. Whether hyperbaric therapy is under-utilized in most states or 

over-utilized in a few is not certain; however, if utilization were to expand across the 

country to levels similar to Texas, HBO2 reimbursements would increase nearly five-fold. 

Additionally, if HBO2 were found to be beneficial for other disease conditions (e.g., 

diabetic foot or non-healing wounds) and consequently added to Medicare’s coverage 

policy, use of HBO2 could substantially increase in every state. 

$14.2 Million was paid in error for hyperbaric treatments (of the 

$49.9 million allowed charges for outpatient hospitals and physicians) 

HBO2 treatments for 32 percent of beneficiaries were identified by our medical review 

team as inappropriate. Either beneficiaries received treatments for non-covered conditions 

(22.4 percent of beneficiaries, $10.5 million) or documentation was not sufficient to 

support HBO2 treatments (9.2 percent, $3.7 million). This projects to total allowed 

charges for HBO2 billed in error by physicians and outpatient hospitals of $14.2 million in 

the sample year (July 1, 1997 to July 1, 1998). (See Appendix D.) This represents 

approximately 28 percent of total payments paid to outpatient facilities and physicians 

during the sample year. While medical review would be necessary to identify most of these 

overpayments, some could have been detected had contractors utilized appropriate 

computer claims processing diagnosis edits. 

The discrepancy between indications recommended by the hyperbaric community 

and those acceptable for Medicare reimbursement contribute to inappropriate 

billing 

Discrepancy exists between the treatment indications approved for Medicare 

reimbursement and indications considered appropriate by the hyperbaric medical societies 

(UHMS and ACHM). The most prominent examples are the extension of treatment to the 

HBO2: Its Use and Appropriateness 9 OEI-06-99-00090 
 diabetic foot and to thermal burns. Appendix E - “Recommended Usage of HBO2 by 

HCFA and Interest Groups”, lists potential indications for HBO2 including HCFA 

coverage, as well as the recommendations of the two medical societies, plus one set of 

international guidelines. The treatment indications for which there are discrepancies 

between HCFA coverage and the domestic interest group guidance are bolded. 

Many facilities rely on information provided by these groups to develop practice standards. 

The differing recommendations of these authorities can create confusion. The failure of 

some providers to recognize the difference between interest group suggestions and 

HCFA’s formal payment policies may lead to inappropriate billing. One example described 

by a representative of UHMS regards the controversy surrounding non-healing wounds.12 

“Reputable hyperbaric physicians around the country have tried to treat [patients with noncovered hypoxic wounds] on the basis of good experimental and clinical evidence justifying 

their treatment plan in terms of arterial insufficiency and acute ischemia as the only 

available means to describe the aforementioned hypoxic wound.” This comment alludes to 

the parallel between covered and un-covered conditions13; and the fact that physicians will 

sway their interpretation of diagnosis codes to align treatment practices with their own 

medical judgements. Difficulty discerning covered from uncovered conditions combined 

with the inclination of many physicians to follow their own medical judgement (as 

influenced by the medical societies) rather than payment guidelines sometimes result in 

inappropriate Medicare claims. 

Diagnosis codes are sometimes used inappropriately to obtain reimbursement for 

uncovered indications 

Although the guidelines specifically describe fourteen indications for which hyperbaric 

treatment is reimbursable by Medicare, some providers have taken great latitude in how 

they interpret those conditions, while others appear to deliberately use inaccurate ICD-9 

codes to bypass carrier and intermediary edits. Our reviewers found 13 percent of 

beneficiaries had diagnoses listed on their claims that misrepresented their true medical 

condition. For example, of the hyperbaric charts reviewed using the diagnosis code gas 

gangrene (n=24), only three were found to have “wet” (a.k.a. gas) gangrene (the only type 

of gangrene covered). Ten of the remaining 21 charts showed a primary indication of “dry” 

gangrene, an indication not covered by CIM 35-10 in and of itself. The reviewers also 

determined that treatment courses in accordance with the CIM 35-10 guidelines tended to 

have billing diagnoses that accurately described the beneficiary’s condition; but, of 

treatment courses that did not comply with the CIM 35-10 guidelines, over half had a billed 

diagnosis that described a secondary or tertiary indication or was deemed to be 

erroneous.14 This relationship (p<.001) suggests that diagnosis codes are, at times, 

selected for the purpose of bypassing the carrier and intermediary edits used to flag 

potentially inappropriate treatments. 

The problems related to diagnosis codes are exacerbated by the absence of ICD-9 codes 

specific to some of the covered conditions (e.g., Meleney’s ulcer and Arterial 

Insufficiency). Contractors, in their interpretation of the 35-10 guidelines to system edits, 

are forced to accept loosely related diagnoses on claims to justify medical necessity. The 

slack created by the interpretation allows physicians to treat non-covered indications 

HBO2: Its Use and Appropriateness 10 OEI-06-99-00090 
without falsifying the diagnosis. A few billing diagnoses, identified by the medical review, 

are frequently associated with non-compliance of the 35-10 guidelines. Claims with a 

billing diagnosis of “chronic ulcer” were found to be out of compliance almost two-thirds 

of the time (p<.001); and, those with a billing diagnosis of “pyoderma” were out of 

compliance in almost half of the cases (p<.01).15 

Some Providers did not provide sufficient documentation to justify Medicare 

reimbursement 

Billing errors and inadequate documentation account for 9 percent of beneficiaries treated 

with HBO2. In most cases, sufficient documentation was simply not provided. An on-site 

review at one of the hospitals failing to provide records resulted in recoupment action and a 

referral for a fraud investigation. While treatments may have been provided, the facility 

was unable to provide the intermediary with adequate documentation (e.g., treatment logs) 

in nearly all of the cases requested. In addition to documentation problems, three charts in 

the sample were counted as inappropriate because they billed Medicare for topical 

hyperbaric oxygen therapy - a procedure explicitly excluded in the reimbursement 

guidelines. Five charts used the 99183 code or the revenue center 413 for related 

procedures other than HBO2 (e.g., basic wound care). Medical records for three charts 

showed that the beneficiary for whom claims were received was never treated with 

hyperbarics. The remainder of this group (12 charts) provided documentation, but it was 

not sufficient to complete the reviews. 

An additional $4.9 million was paid for treatments deemed to 

be excessive 

Eleven percent of beneficiaries were treated for appropriate indications, but received a 

greater number of treatments than were considered medically necessary by our physician 

reviewers. The excessive treatments represent $4.9 million paid for potentially ineffective 

procedures. (See Appendix D.) The only controls concerning the length of therapy are a 

requirement that courses of therapy extending beyond two months be reviewed and that 

treatments should be medically necessary. 

Our review raised several quality of care concerns 

Another $11.1 million was spent on treatments of questionable quality 

Of the beneficiaries appropriately treated with hyperbarics, 37 percent16 received treatments 

that likely did not yield the maximum benefit possible. This projects to $11.1 million spent 

on such treatments. We examined two proxy variables for quality of care: (1) insufficient 

progress to justify continuation of therapy, and (2) inappropriate or inadequate testing. Of 

beneficiaries treated for appropriate indications, 35 percent did not show sufficient 

documented progress to justify continuation of the therapy; and 15 percent did not have 

appropriate testing to confirm a diagnosis supporting the use of hyperbarics. (See 

Appendix D.) Existing Medicare guidelines do not set testing or monitoring standards; 

however, some of these services might be deemed medically unnecessary. 

HBO2: Its Use and Appropriateness 11 OEI-06-99-00090 
Physician attendance remains a point of contention 

Two perspectives on the meaning of ‘attendance’ are prominent in the hyperbaric 

community: (1) the physician is physically present during the entirety of the treatment and 

uses that time to manage the patient’s overall care; and (2) physicians remain available to 

manage rare emergency situations. Over 75 percent of medical directors agree that 

physician attendance is necessary to promote either safety or quality of care or both. Fiftysix percent of facilities claim to have a physician in the same or adjacent room 100 percent 

of the time. In contrast, part-time physicians and those that supervise, but do not 

physically attend treatments, tend to be of the opinion that their purpose in attendance is 

not to manage the patient, but to manage emergencies. 

Our review indicates physician attendance is strongly correlated with quality of care 

and the reduction of inappropriate billing. Almost two-thirds of medical directors do 

support the notion that physician attendance is necessary to achieve quality. Similarly, our 

medical review results supported this concept, showing a significant relationship (p<.001) 

between quality of care variables and physician attendance and between compliance with 

HCFA guidelines and physician attendance (p<.001). These relationships provide support 

for requiring physician attendance during all treatments. For example, 74 percent of the 

payments termed “inappropriate” by our reviewers did not appear to have a physician in 

attendance. We cannot be certain that physician attendance would have corrected all of 

these payments, but the strong relationship between quality and attendance suggests a 

potential for reducing inappropriate payments.17 

Many facilities do not require physical physician attendance. The reviewers 

determined that more than 25 percent of beneficiaries had no physician oversight of their 

treatments; and twice that many (44 percent) did not have a physician in attendance at their 

treatments.18 Self-reported data from facilities confirms that some facilities (at least 10%) 

never have a physician in attendance and approximately one quarter have physicians in 

attendance less than half of the time. Over half of the facilities surveyed stated that 

supervising physicians were employed part-time, if at all. 

Training requirements may provide a means of promoting quality care 

Some local medical review policies (LMRPs) aim at improving the quality of care by 

requiring physician attendance and setting qualifications or credentialling requirements for 

the supervising physicians. One policy implemented by Blue Cross and Blue Shield of 

Texas (now Trailblazers) sets such requirements. Under this policy, the supervising 

physician must meet the following criteria: 

(1) Training, experience and privileges to manage cardiopulmonary 

emergencies; 

(2) Training, experience and privileges to manage emergency myringotomies; 

(3) Completion of a 60 hour course in hyperbaric medicine recognized by 

UHMS or ACHM 19; and, 

(4) Completion of 16 CME credits every two years after credentialling. 

HBO2: Its Use and Appropriateness 12 OEI-06-99-00090 
Only 41 percent of the facilities we surveyed have even one physician who meets these 

requirements. Facilities employing at least one full-time doctor meet the requirements 

more often than those that do not.20 A recent proposal by HCFA to modify the CIM 35-10 

guidelines suggested adopting requirements such as these. Although the hyperbaric 

societies do support training requirements, they and the American Medical Association 

(AMA) object to the imposition of such requirements by HCFA on the grounds that 

credentialling is the responsibility of hospitals or licencing boards and does not 

meaningfully fall under the jurisdiction of the government. However, we believe HBO2 is a 

service highly vulnerable to misuse (as seen by our medical review). It is also a procedure 

that generates little attention because a low number of patients are affected and because the 

total dollar amount in jeopardy is relatively small. In such a case, a national credentialing 

or training policy would ensure all contractors institute such requirements. 

Many carriers and intermediaries play only a limited role in assuring the quality of 

hyperbaric care 

Although the peer review organizations (PROs) may be primarily responsible for ensuring 

the quality of care provided in facilities, there are several ways that carriers and 

intermediaries could promote a higher quality of care, such as communicating new 

developments in medical standards highlighting differences between medical opinions and 

payment guidelines, and performing periodic post-pay edits to confirm that diagnostic and 

ancillary services are provided appropriately. From surveying the Medicare medical 

directors about their organization’s activities promoting quality care, we found a mixed bag 

of approaches to quality issues. Over half report that they provide voluntary guidance 

upon request and use edits to confirm that diagnostic and ancillary services are provided 

appropriately. However, only 34 percent and 41 percent, respectively, publish standards of 

HBO2 care in a regular newsletter or deny claims when sub-standard care is found. 

Although prescriptive policies are somewhat controversial, 13 percent did report providing 

suggested protocols to hyperbaric facilities. Several other medical directors mentioned 

referring cases to the PRO, creating additional requirements (such as attendance, 

credentialling, or specifying appropriate settings) in their LMRPs, and one medical director 

stated that his carrier/intermediary performs pre-pay reviews for hyperbaric treatments. 

Some carriers and intermediaries do not apply edits and 

appropriate medical review standards to ensure compliance 

with the CIM 35-10 

Billing data from our sample showed evidence that carriers and intermediaries do not 

uniformly use edits to detect procedures billed with inappropriate diagnoses; nor is there a 

uniform protocol for reviewing medical records for appropriateness of indication and 

medical necessity after two months of treatment.21 It appears that 23 percent of bills are 

paid with an inappropriate billing diagnosis (which could have been identified by a prepayment edit). Of these, 53 percent are not in accordance with CIM 35-10 and should not 

have been paid. (This relationship is significant at p=.001.)22 

HBO2: Its Use and Appropriateness 13 OEI-06-99-00090 
Local medical review policies and implementation of system edits vary by contractor. The 

implications of such variation include likely differences in coding patterns and rates of 

inappropriate reimbursements. Further differences exist in the level of medical review 

employed. As an example, one intermediary only verifies that the billing diagnosis is 

covered (ICD-9 code is valid) and does not routinely review medical records to 

substantiate the authenticity of the patient’s condition or question the amount charged. This 

limited medical review process leaves the contractor vulnerable to fraud, inappropriate 

utilization, and inflated charges. Our review found one hospital taking extreme advantage 

of these vulnerabilities. The facility routinely charged $5,500 and the contractor allowed 

$4,400 for each individual treatment. In contrast, most facilities average allowed charges 

between $250 and $300. Upon our request for the hyperbaric facility’s records, they sent 

virtually no documentation that the treatments were even performed. At our request, postpayment review at the facility was performed by the intermediary; and consequently, $1.3 

million in erroneous payments were identified and recoupment initiated. Although these 

problems are extreme, the lack of oversight described is not unique. For example, another 

intermediary reported that facilities were on the “honor system.” As a result, claims were 

being paid for non-covered conditions such as multiple sclerosis, heart attacks, cancer, and 

pneumonia. (Since being contacted by the Office of Inspector General (OIG), this 

contractor reported it has begun using a front-end editing tool called Super Op to detect 

these situations.) 

According to self-reported data, 42% (29/68) of medical directors confirm their institutions 

have no edits in place for hyperbarics. The CIM 35-10 guidelines describe at least two 

conditions for which edits are a feasible method of screening: (1) limiting coverage to 

fourteen diagnosable conditions; and, (2) requiring a review for any course of treatments 

extending beyond two months. Almost 60 percent of carriers and intermediaries do not 

have system edits for both of these conditions.23 

Once a bill is identified as requiring a pre- or post-payment review, the mechanism can 

differ by carrier or intermediary. Fifteen percent of contractors self report that the process 

is comprised merely of reviewing diagnosis codes and nothing else. In general, 

approximately 60 percent of medical directors reported that they do confirm that 

treatments are actually provided and that those treatments are medically necessary and 

within HCFA's diagnosis parameters. However, the majority (72 percent) do not have 

medical review procedures to routinely detect over-utilization of treatments, whether 

hyperbaric therapy is used adjunctively (not as a primary therapy), and whether progress is 

monitored appropriately by a physician throughout the treatment.24 

HBO2: Its Use and Appropriateness 14 OEI-06-99-00090 
HCFA’s guidance for this procedure is limited 

The guidance provided by HCFA controls usage only by (1) limiting indications for 

treatment, (2) creating a provision that HBO2 must be adjunctive to primary therapy, and 

(3) denying coverage for topical hyperbaric oxygen therapy. The guidance may be found in 

Appendix B. Although these restrictions appear quite clear, in application they often 

become vague, and in some areas, inconsistent.25 

Many carriers (68%) and intermediaries (54%) have no local medical review policy 

or payment guidelines independent of the CIM 35-10 

When asked about efforts to convey the intent of CIM 35-10 to physicians providing 

services, over one quarter (12/44) of carrier medical directors stated they do nothing 

beyond relying on information within the CIM 35-10 guidelines. As one medical director 

expressed, “CIM 35-10 is a national coverage policy. In these cases [referencing potential 

misinterpretations], we feel it should be HCFA and not local contractors that clarify 

intent.” This stand may not be the position of all contractors; but in light of the widespread misuse identified by the medical review analysis, one could conclude that the 

existing guidelines are not sufficient. 

Carriers and Intermediaries vary in how they interpret and implement CIM 35-10 

A comparative analysis of acceptable ICD-9 codes for four local medical review policies 

and HCFA's 1999 proposed revision to CIM 35-10 may be viewed in Appendix F. The 

table clearly shows significant variation in interpretations of the CIM 35-10 guidelines. For 

example, a LMRP from Transamerica of Southern California accepts only one code for 

arterial insufficiency (443.9 peripheral vascular disease), while HCFA’s proposed 

interpretation of the indication arterial insufficiency included three codes very different 

from Southern California (444.21, 444.22, and 444.81, all for arterial embolism). The two 

translations into ICD-9 codes without the context of the overarching indications might lead 

physicians to draw very different conclusions about Medicare coverage. Further examples 

of interpretation problems include the extent of coverage for skin grafts, the use of the term 

Meleney’s ulcer26, and coverage for the Marx protocol27. 

At the time of our survey, HCFA had previously released a memo stating its interpretation 

of the condition “preparation and preservation of a compromised skin graft” meant that a 

graft must have been previously placed in order for the treatments to be reimbursable. This 

clarification was a response to the confusion regarding the intent of the word preparation in 

the term “preparation and preservation of a compromised skin graft.” Our medical review 

demonstrated this problem. Twenty-five percent of beneficiaries treated under the guise of 

this indication had neither a previous compromised graft nor a graft ultimately placed (64 

percent never had a previous graft failure and 44 percent did not have a graft ultimately 

placed). Because of the confusion related to the skin graft indication, some contractors 

ceased coverage of preparation of a skin graft entirely, leaving only the preservation 

segment of this indication. When asked, in general, if the preparation of a skin graft is a 

HBO2: Its Use and Appropriateness 15 OEI-06-99-00090 
covered condition, only 38 percent of Medicare medical directors agreed that it is covered 

at all (regardless of a previously compromised graft). 

Another such example is the interpretation of the condition “progressive necrotizing 

infections”. Specifically included with the indication are the terms necrotizing fasciitis and 

Meleney’s ulcer. This creates a problem because there is no ICD-9 code describing 

Meleney’s ulcer, a very specific condition. In the absence of an appropriate code, bills are 

submitted with the diagnosis codes of necrotizing fasciitis, pyoderma, and cellulitis. 

Pyoderma and cellulitis are very broad terms and have created a niche for billing a broad 

variety of ulcers that do not necessarily fit the diagnostic criteria of Meleney’s ulcer. 

Medical director’s interpretations of the over-arching indication (“progressive necrotizing 

infections”) have ranged from a broad interpretation (including any wound with necrotic 

edges) to the specific classification of this indication as only applying to life-threatening 

emergency treatment of fasciitis. 

Coverage of the condition osteoradionecrosis poses a different interpretation problem. 

There is no effective way to diagnose this condition until a breakdown of the bone occurs. 

When symptoms are observed, it is often too late to gain much benefit from HBO2. In this 

case, the primary usage of HBO2 is prophylactic, most frequently utilized in accordance 

with the Marx protocol. Although no specific exception to the Medicare policy allows 

preventative care, this type of procedure is representative of as much as nine percent of 

HBO2 beneficiaries. Moreover, almost 40 percent of medical directors state that this form 

of therapy is reimbursable and an additional 30 percent believe that, although it is not 

covered, it should be. This form of hyperbaric therapy is one of the more well-supported in 

scientific literature28; however, the conflict between these two Medicare policies has never 

been addressed. 

Standards of care have not been incorporated into HCFA’s guidance to reduce 

over-utilization 

The number of treatments considered appropriate is not the same across indications, nor is 

the testing required to determine diagnoses. In 1995, the ACHM created “Preferred 

Practice Protocols” that, in most cases, describe diagnostic and treatment patterns specific 

to each indication. In addition, the 1999 revision of UHMS’s “Committee Report” 

includes a utilization review for each indication. To date, neither these nor similar 

protocols have been promoted by HCFA as a method of evaluating appropriate treatment. 

Many hyperbaric practices are started with little information on proper utilization or 

reimbursement policies. According to interviews with hyperbaric physicians, many 

hyperbaric units are not started by physicians. They are started by facilities which may 

have little knowledge of proper utilization and standards of care. This lack of knowledge is 

a likely cause for non-compliance with HCFA’s guidelines, excessive treatments and a 

lower quality of care. Solicitations and contractual arrangements with hyperbaric 

entrepreneurs contribute to this problem. Some manufacturers will install chambers in a 

facility at no cost. The incentive for the manufacturer is that they receive a portion of the 

revenue generated by the chamber. This type of arrangement allows hospitals to institute 

HBO2: Its Use and Appropriateness 16 OEI-06-99-00090 
such facilities with no capital outlay cost (and possibly no risk). The draw from institutions 

seeking a chamber for profit, combined with low risk acquisition, increases the pool of 

potential facilities thereby increasing the variation in the rigor of practice standards and 

expertise of personnel. Evidence supporting this claim is anecdotal; however, the 

implications in terms of total billing and the degree to which billing might be inappropriate 

may be significant. 

Many billing physicians and facilities have little HBO2 experience. Nearly half of all 

physicians (43 percent) and hospitals (47 percent) billing hyperbarics in 1998 treated no 

more than 5 Medicare beneficiaries. Half of these treated only one beneficiary. This 

finding raises concerns about the experience and expertise of these providers regarding 

current HBO2 practice protocols. 

Many facilities do not independently substantiate the diagnostic basis for treatment. 

Our reviewers found that almost half of beneficiaries whose treatments were considered to 

be appropriate did not receive proper testing to confirm their diagnosis. Because 

hyperbaric units are considered secondary or tertiary treatment centers, documentation of 

diagnosis was sometimes never confirmed or even documented within the hyperbaric 

facility. Those records are expected to be maintained by the patients’ primary physicians. 

In some cases, we found only an order for treatment and treatment logs. This reliance on 

other physicians to determine the necessity of treatment may be a contributing factor to the 

number of patients treated inappropriately. 

An absence of documentation guidance combined with the inadequacy of medical 

records found in this review suggests this area needs attention. Inadequate 

documentation was a complicating factor in our medical review. The extent of 

documentation varied a great deal. In a few cases, facilities provided only a date of service, 

documentation that a “dive” took place and a quick note on how the patient tolerated 

treatment. Such records are grossly inadequate. Oxygen delivered in a pressurized 

environment is analogous to a drug; and considering such a comparison, the dosage should 

be adequately recorded along with other pertinent information. Our expectation of 

documentation was that each record would include: 

! a history and physical, 

! an assessment of the patient as a candidate for hyperbarics, 

! an evaluation of medical necessity, 

! a treatment plan, 

! regular documentation of progress and reassessments of the

treatment plan, 

! and daily logs of the procedure (including ascent time, descent time, 

total bottom time, dose of oxygen, pressurization level (ATA), 

documentation of attendance, and a recording of events). 

This full level of documentation was rarely provided. Only 28 percent of records reviewed 

showed both an adequate plan of care and adequate objective treatment measures.29 The 

absence of this information, along with the previously discussed problem 

HBO2: Its Use and Appropriateness 17 OEI-06-99-00090 
that many facilities do not independently substantiate diagnoses, suggests the possibility of 

a systemic problem with the determination of medical necessity. In addressing this issue, 

we found no guidance from HCFA on the necessary level of documentation to support 

Medicare billing. The medical directors surveyed had differing opinions on what 

constitutes adequate documentation for billing. Many feel that it is the responsibility of the 

referring physician to maintain records supporting medical necessity (whether or not these 

medical directors intended on using referring the physician’s records in a post-pay review 

varied). Other medical directors argued that it is the responsibility of the hyperbaric facility 

to keep sufficient documentation of the diagnosis and that the treatment is reasonable and 

necessary. 

The role of the hyperbaric physician is unclear 

The duties implicit in billing the 99183 hyperbaric code are unclear. The role of the 

physician has been defined by ACHM as an exhaustive list of duties to be performed 

before, during and after treatment. The ACHM stated that this list was produced at the 

express request of HCFA to describe the physician work as a component of the resourcebased relative value system (RBRVS), on which the physician payment of approximately 

$140 is based. The list of duties described by the ACHM suggests that oversight of the 

wound and some routine wound care are implicit in the duties of the 99183 code for 

hyperbarics.30 However, the AMA’s “Physician’s Current Procedural Terminology” since 

1994 and similarly, the Federal Register in 1993 state that “E/M [Evaluation and 

Managment] services and/or procedures (e.g., wound debridement) provided in a 

hyperbaric oxygen treatment facility in conjunction with a hyperbaric oxygen therapy 

session should be reported separately.” The absence of a document describing the duties 

implicit in billing the 99183 code creates a vulnerability where some physicians bill for 

routine services in addition to the 99183 code while others believe that the same services 

are included in the fee assessed for hyperbarics. 

The definition of “attendance” is unclear. An additional source of confusion relates to 

the previously discussed concept of attendance and supervision. Many hyperbaric doctors 

disagree on whether a doctor can supervise a treatment without being in attendance. 

However, if the ACHM guidelines truly do represent the physician’s responsibilities, his or 

her duties could not be performed without being in physical attendance for each treatment. 

On the other hand, some argue that this procedure is routine; and consequently, a physician 

might merely be available in case of emergencies, and thus, could supervise the treatments 

from afar. In light of these varied opinions, HCFA announced an additional code for 

hyperbaric oxygen treatments not requiring physician attendance (G0167) in the November 

2, 1999 issue of the Federal Register. This code allows for the same payment to the 

physician as the 99183 code, minus the cost associated with physician work. There is some 

concern in the medical community that the existence of two codes will have significant 

implications in terms of documentation requirements. If a determination of medical 

necessity is required for each code, some form of triage will be necessitated. In addition, 

58 percent of medical directors do not personally support the addition of the new code. 

For, if attendance is truly a cornerstone of quality, the additional code undermines the 

rationale originally implied within the 99183 code. 

HBO2: Its Use and Appropriateness 18 OEI-06-99-00090 
Recent and impending regulatory changes may affect growth 

Several changes (both recently effected and proposed) to the reimbursement structure and 

the CIM 35-10 coverage guidelines may have an impact on the hyperbaric industry. 

Coverage Guidance: On three occasions in 1999, revisions to the current CIM 35-10 have 

been proposed and then delayed. The most recent proposal is delayed until April 1, 2001. 

While HCFA contended that the proposed revisions did not make substantive changes, 

some hyperbaric physicians argued that the modifications would reduce coverage and 

impose additional requirements (such as physician attendance) that could not be met by 

many facilities and would consequently cause many HBO2 providers to go out of business. 

Outpatient Rate: When payment rates were initially calculated by the HCFA, 

reimbursement was proposed at $145. (Strikingly, the beneficiary was responsible for 

nearly all of this amount with a coinsurance of $141.) This reimbursement rate was far 

short of the average costs, which ranged between $273 and $292 as calculated by the 

Hyperbaric Oxygen Therapy Association (HBOTA). The obvious concern within the 

hyperbaric community was that low reimbursement levels might cause HBO2 units to shut 

down or force hospitals to subsidize their costs. 

In response to these concerns, the HCFA reclassified the HBO2 procedure as a “new 

technology” and reset the reimbursement rate at $75 per 30 minute period. The 

reclassification as a new technology also replaces the excessively high beneficiary 

coinsurance payment with the standard 20 percent. Since a typical HBO2 treatment is 90 

minutes long, the new reimbursement rate is approximately $225. While still short of the 

industry’s estimated costs, this rate appears fair, given that our analysis of 1998 payments 

shows half of the facilities have average charges over this amount and half are under this 

amount. The overall average allowed for all facilities was $265 ($605 submitted and $145 

paid). 

Physician Fee: Changes to the Medicare fee schedule payments for physician services are 

gradually decreasing the reimbursement rate from 1998 levels. Between 1998 and 2002, 

the practice expense relative value is expected to decrease by 60 percent (from 1.81 to 

0.73). This reduction will result in a 33% reduction in current payments to approximately 

$100. The reduction is a result of congressionally mandated changes in the fee schedule 

from charge-based RVUs to resource-based RVUs. Our medical reviewers (who are 

currently practicing HBO2 physicians) are concerned that these reductions may discourage 

physicians from specializing in hyperbarics, which could further reduce access to the 

procedure. However, the mechanism utilized to establish fee schedules has several 

protections to ensure that rates are calculated fairly. These mechanisms include an appeal 

process through HCFA and a practice expense advisory panel of AMA representatives to 

advise HCFA when resource inputs are incorrect. 

HBO2: Its Use and Appropriateness 19 OEI-06-99-00090 
R E C O M M E N D A T I O N S 

Our results show that a significant percentage of HBO2 is provided inappropriately. Either HBO2 

should never have been used (not a covered diagnosis), excessive treatments were provided, or 

documentation of services was not available. 

To address concerns raised in this report, we recommend that the Health Care Financing 

Administration: 

! Initiate its national coverage decision process for HBO2. 

This review is requested because (1) questions persist concerning the appropriate 

usage of HBO2, (2) there are program integrity issues surrounding significant 

inappropriate payments, and (3) there are conflicting carrier and intermediary 

policies. Considering the overlap of HBO2 with other wound-care procedures, this 

review might consider HBO2 within the broad context of wound care and in terms 

of its relative cost-effectiveness. 

! Improve policy guidance: 

1. Provide clear descriptions of covered conditions; 

2. Propose additional ICD-9 codes as needed to more closely parallel 

covered conditions; 

3. Establish a clear physician attendance policy; 

4. Consider establishing training requirements; 

5. Consider incorporating clinical standards of patient selection and 

treatment protocols designed with the aid of hyperbaric physicians; 

and, 

6. Specify medical record documentation requirements. 

! Improve oversight: 

1. Require contractors to initiate edits and medical review procedures 

which insure that uncovered diagnoses are not paid and high 

treatment thresholds are subject to review. 

2. Explore the establishment of a registry of facilities and/or physicians 

providing HBO2 to improve communication and facilitate 

monitoring. 

HBO2: Its Use and Appropriateness 20 OEI-06-99-00090 
Agency Comments 

The Health Care Financing Administration (HCFA) generally concurs with our 

recommendations. They expressed that their goal, as ours, is to provide beneficiaries 

access to effective services and to make payments for those services appropriately. We 

recognize HCFA’s on-going efforts to improve and clarify Medicare’s policy on Hyperbaric 

Oxygen Therapy (HBO2) such as responding to national coverage requests and issuing 

guidance memoranda. We also appreciate their plan of alerting carriers to the 

vulnerabilities associated with this procedure and calling for increased carriers’ oversight. 

See appendix H for the full text of HCFA’s comments. 

HBO2: Its Use and Appropriateness 21 OEI-06-99-00090 
ENDNOTES 

1. At times oxygen dosages may range anywhere between 30 and 100 percent. 

2. Camporesi, Enrico, Hyperbaric Oxygen Therapy: A Committee Report; Undersea and 

Hyperbaric Medical Society, Kensington, MD: Revised 1996. 

3. The length of treatment is measured in total bottom time or TBT which does not include 

the time dedicated during ascent to increased atmospheric pressure or descent to surface 

pressure. 

4. According to our review, 18 percent of beneficiaries exhibit side effects (significantly 

greater than the literature suggests). The most common side effect is ear-related trauma, 

representing 63 percent of all observed side effects. While side effects are generally not 

severe, two individuals within our sample showed signs of oxygen toxicity. This relates to 

1.3 percent of the population which also is significantly greater than the expected value 

cited in the literature. 

5. These statistics were based on our analysis of the 1998 National Claims History file 

maintained by HCFA. Estimated reimbursement for facility payments was based on an 

approximation of the proportion of payment attributed to HBO2 according to a cost to 

charge ratio calculated for revenue center 413 (hyperbaric oxygen treatment). 

6. The Agency for Healthcare Research and Quality (AHRQ) was established in 1989 as the 

Agency for Health Care Policy and Research. “Reauthorizing legislation passed in 

November 1999 establishes AHRQ as the lead Federal agency on quality research. 

AHRQ, part of the U.S. Department of Health and Human Services, is the agency charged 

with supporting research designed to improve the quality of health care, reduce its cost, 

and broaden access to essential services. AHRQ’s broad programs of research bring 

practical, science-based information to medical practitioners and to consumers and other 

health care purchasers. 

In December 1995, the Agency for Health Research and Quality (AHRQ) wrote a memo 

to HCFA regarding the medical conditions covered by the CIM 35-10 finding that 

“patterns of use do not validate the clinical effectiveness of any intervention, and it cannot 

be concluded that its use by proponents has either established its acceptance by the general 

medical community or provided acceptable proof of clinical utility.” 

7. In evaluation of the costs and benefits of using HBO2 to treat diabetic feet, the American 

Diabetic Association (ADA) recently concluded that, although adequate research 

(randomized controlled trials) was not available, HBO2 use “is reasonable” to treat severe 

and limb- or life-threatening wounds. (Special Report by the ADA, “Consensus 

Development Conference on Diabetic Foot Wound Care, 7-8 April 1999, Boston MA”, 

Advances in Wound Care, Vol. 12: No. 7; September 1999.) 

HBO2: Its Use and Appropriateness 22 OEI-06-99-00090 
8. The Blue Cross and Blue Shield Association, Technical Assessment Center; Assessment 

Program Vol. 14: No. 13: August, 1999. 

9. For simplicity in this figure, each beneficiary was counted in only one category based on a 

prioritization of conditions. Also note that some indications were combined to create a 

more meaningful breakdown of the indications. 

10. Conditions not covered by the 35-10 guidelines including conditions not meeting the 

qualifications (e.g., chronic and refractory) were counted in the category ‘non-covered 

indications’. The discrepancy between non-covered conditions as primary indications 

(33.5%) and treatments not compliant with CIM 35-10 (22.4%) describes courses of 

therapy that either (1) were compliant with CIM 35-10 based on a secondary or tertiary 

indication, or (2) were identified as being compliant by the physician reviewers, but a 

covered condition was not indicated as a reason for treatment. 

11. Schwab, Robert (On Small Business), Denver Post; “Health care tempts firms local 

entrepreneurs market new products in growing field.”; Denver, Colo.; Oct 17, 1998. 

12. Commenting on Appendix D of this report, one representative of UHMS stated, “This is 

the crux of this issue as far as HBO2 in the broad picture of wound healing is concerned. 

Both of the US professional organizations responsible for providing clinical guidelines, 

similar international organizations, and now BC/BS with its recent endorsement of HBO2 

for chronic non-healing wounds (Assessment Program vol 14: No 13, Aug, 1999) define 

the clear value of HBO2 in ischemic/hypoxic wounds where such hypoxia cannot be 

adequately corrected by other means (refer also to the ADA statement (Diabetes Care 

22(8): 1354-1360, 1999) but responsive to HBO2 should be treated. Reputable 

hyperbaric physicians around the country have tried to treat these patients on the basis 

of good experimental and clinical evidence justifying their treatment plan in terms of 

arterial insufficiency and acute ischemia as the only available means to describe the 

aforementioned hypoxic wound. HCFA has not kept pace with this long standing 

recommendation by the UHMS Oxygen Therapy Committee (dating back at least to 

1989), the recent ADA recommendation, and now the recommendation by the BC/BS 

technology assessment. We have medically and physiologically defined these wounds 

using the best available descriptions of ischemia, but this is really both inadequate and 

confusing and should be resolved by a clearly defined new indication and terminology.” 

13. One source of confusion in CIM 35-10 is the potential parallel between covered and 

uncovered conditions. Acute peripheral arterial insufficiency and preparation and 

preservation of a compromised skin graft (covered conditions), may be used to describe or 

treat conditions that are explicitly uncovered such as cutaneous, decubitus, and stasis 

ulcers; or skin burns. There is no terminology as to which standard has precedence. 

14. A chi-square test for this relationship was significant at p<.001 using a Sudaan-weighted 

sample. 

HBO2: Its Use and Appropriateness 23 OEI-06-99-00090 
15. A chi-square test of significance found relationships between compliance with the CIM 

35-10 guidelines and several billing diagnosis in the Sudaan-weighted sample. Both 

positive and negative relationships were found to be significant. Those mentioned in the 

text (pyoderma and chronic ulcer) were more likely to be out of compliance. 

16. The 37 percent represents beneficiaries who did not meet the review expectations in one 

or more of the two quality of care variables. This group may overlap with the group of 

beneficiaries having excessive treatments. 

17. The variables evaluated for a relationship with physician attendance and their associated p 

values from a Sudaan-weighted chi-square follow: 

Variable Quality p Value with 

Attendance 

p Value with 

Supervision 

1. Compliance with 35-10 <.001 <.001 

2. Sufficient progress noted to justify 

continued treatment 

<.001 <.001 

3. Appropriate testing prior to treatment .023 .020 

4. Either quality of care variables 

(appropriate testing or sufficient progress 

to justify continuation) 

<.001 <.001 

18. As one of our reviewers explained, it is difficult to determine if a physician is truly in 

attendance. There may be documentation of attendance; combined with other evidence 

suggesting that they were not there. Some examples of this include (1) notes are written 

by the nurse but signed by the doctor, (2) doctors have written notes but they do not 

follow the chronological sequence of the nurse’s notes, (3) documentation that the doctor 

was paged or faxed. Despite these difficulties, we asked our panel of experts to make a 

judgement regarding the level of attendance present. 

19. There is some debate as to whether the requirement of 60 hours of hyperbaric education 

was intended to be a single course or should be divided between multiple courses. 

20. The chi-square relationship is significant at p=.001 

21. The CIM 35-10 designates that a medical review should be performed in instances that the 

course of therapy exceeds two months. 

22. A relationship between appropriateness of the billed diagnosis and compliance with the 

CIM 35-10 guidelines was found to be a significant chi=square relationship at p=.001 in 

the Sudaan weighted sample. 

23. Medical directors self-reported whether the following conditions would elicit a medical 

review: 

HBO2: Its Use and Appropriateness 24 OEI-06-99-00090 
1. Bills for indications not covered under 35-10 81% 

2. Treatments courses extending beyond two months 31% 

3. Any measure of length of treatment 43% 

4. Conditions 1 and 2 (as listed above) 25% 

5. Conditions 1 and 3 (as listed above) 41% 

24. Medical directors self-reported their medical review process to include: 

Confirm treatment is not over-utilized 53% 

Confirm progress is monitored appropriately 65% 

Confirm primary therapy for condition is also provided 65% 

25. The currently effective version of the CIM 35-10 is separated into four distinct sections: 

A, B, C, and D. Part A identifies the conditions that are covered. Part B identifies explicit 

conditions that should not be covered. Part C states that reasonable utilization parameters 

should be used; and, Part D states that topical oxygen does not qualify for reimbursement. 

One source of confusion is the potential parallel between covered and uncovered 

conditions. Acute peripheral arterial insufficiency and preparation and preservation of a 

compromised skin graft, covered conditions, may be used to describe or treat conditions 

that are explicitly uncovered such as cutaneous, decubitus, and stasis ulcers; or skin burns. 

There is no terminology as to which standard has precedence. There is currently some 

discussion that any new policy will remove the Part B restrictions; however, this act alone 

will not resolve this problem. Subpart C provides a short description of reasonable 

utilization parameters only specifically referencing length of therapy course. However, 

legal advice sought by Dr. Kelly Hill of the ACHM in 1995 found that “the section [Part C 

of the CIM 35-10] must be interpreted to expand rather than limit covered services.” The 

attorney explained that “clearly if a provision contains lists which are both inclusive and 

exclusive, the proper reading of it would be that those items excluded are explicit. Since 

the provision cannot itemize all possible items inclusive, that part of the provision is 

expandable. Such is the case with Section 35-10 because Subpart C provides a 

mechanism where additional items may be considered as included. Such an interpretation 

is proper since it gives meaning to all subparts of Section 35-10, not just one subpart.” 

(Letter dated 3/8/95 from Attorney Kent Masterson Brown to Kelly Hill, M.D.) 

26. Meleney’s Ulcer was originally defined in 1926 as “a progressively expanding infection 

created by the synergism between aerophilic and anaerobic/microaerophilic bacteria”, the 

ACHM Preferred Practice Protocols now equate the terms Meleney Ulcer and progressive 

necrotizing infection. This reference now states that the diagnostic criteria includes “a 

slowly (1 to 2 cm per day) progressive, superficial necrotizing environment, and 

microvascular thrombosis in a full thickness ulcer.” 

HBO2: Its Use and Appropriateness 25 OEI-06-99-00090 
27. R. Marx created a specific hyperbaric oxygen therapy protocol for the prophylactic 

treatment of osteoradionecrosis of the jaw prior to dental procedures. The use of this 

therapy is considered to be a standard of care by many dentists and hyperbaric physicians. 

28. Marx, R., Johnson, R., Kline, S. “Prevention of Osteoradionecrosis: A Randomized 

Prospective Clinical Trial of Hyperbaric Oxygen Versus Penicillin,” JADA, Vol. 111, July 

1985. 

Marx, R. “A New Concept in the Treatment of Osteoradionecrosis,” J Oral Maxillofacial 

Surgery 1983; 41: 283-288. 

Marx,R., and Myers, R. “Use of Hyperbaric Oxygen in Postradiation Head and Neck 

Surgery,” NCI Monographs, Number 9, 1990. 

Epstein, J., Lepawsky, M., McKenzie, M., et al. “Hyperbaric Oxygen and Postradiation 

Osteonecrosis of the Mandible,” Oral Oncol, Eur J Cancer, Vol 29B, No. 3, 201-207, 

1993. 

Consensus Statement: Oral Complications of Cancer Therapies. National Institutes of 

Health Consensus Development Panel. NCI Monographs, Number 9, 1990. 

Bergstrom, K., Branemark, P., Granstrom, G., et al. “A Detailed Analysis of Titanium 

Implants Lost in Irradiated Tissue,” The International Journal of Oral & Maxillofacial 

Implants, Vol 9, No 6, 1994. 

Dempsey, J., Hynes, N., Smith, T., et al. “Cost Effectiveness Analysis of Hyperbaric 

Therapy is Osteoradionecrosis,” Can J Plast Surg., Vol 5, No 4, Winter 1997. 

29. Less than 40 percent had both progress measures and a plan of care in any form. 

30. ACHM “Physician Duties in Hyperbaric Medicine”, 1993. Wound care is referenced 

under Physician Work Performed Before or After Hyperbaric Treatment, with the Patient 

numbers 3-5. 

HBO2: Its Use and Appropriateness 26 OEI-06-99-00090 
APPENDIX A 

Cellular and Biochemical Benefits of Hyperbaric Oxygen 

Although the number of indications for hyperbarics may be quite large, the mechanisms of therapy 

are few. HBO2 is believed to (1) enhance perfusion, (2) stimulate angiogenesis, (3) supersaturate 

the bloodstream with oxygen, (4) act as a bactericide, and (5) prevent the production of alpha 

toxin. The theories supporting these mechanisms are based on fundamental principles of medicine 

and physics. 

Perfusion 

Hyperbaric oxygen therapy increases the concentration of dissolved oxygen in the blood, 

which enhances perfusion. “At sea level the blood (plasma) oxygen concentration is .3 ml 

per deciliter of blood, assuming normal perfusion. 100% oxygen at ambient (normobaric 

pressure increases the amount of oxygen dissolved in the blood fivefold to 1.5 ml per 

deciliter, and at 3 atmospheres, the dissolved oxygen content is approximately 6 ml per 

deciliter, more than enough to meet resting cellular requirements without any contribution 

from oxygen bound to hemoglobin.”2 

Angiogenesis 

Hyperbaric oxygen therapy stimulates the formation of a collagen matrix so that 

angiogenesis, a necessary component of wound healing, may take place. 

Supersaturation of Blood with Oxygen 

Hyperbaric oxygen therapy replaces inert gas in the bloodstream with oxygen, which is then 

metabolized by the body. “Boyle’s law, which states that the volume of gas in an enclosed 

space is inversely proportional to the pressure exerted on it, governs this process and 

explains some of the beneficial effects of hyperbaric oxygen in conditions caused by the 

formation of gas bubbles.”2 

Bactericide 

! Kills certain anaerobes

! Prevents growth of species such as Pseudomonas

! Restores neutrophil-mediated bacterial killing in previously hypoxic tissues

Hyperbaric oxygen therapy reduces leucocyte adhesion in reperfusion injury, preventing the

release of protease and free radicals which cause vasoconstriction and cellular damage. “Local

hypoxia predisposes wounds to infection, because the neutrophil-mediated killing of bacteria by

free radicals is decreased. HBO restores this defense against infection and increases the rate of

killing of some common bacteria by phagocytes. In addition, HBO alone is bactericidal for

certain anaerobes.”2

HBO2: Its Use and Appropriateness A-1 OEI-06-99-00090 
Prevention of the Production of Alpha Toxin 

Hyperbaric oxygen therapy inhibits the production of alpha toxin, a by-product of gas 

gangrene. 

Sources: 

1. Leach, et al. , “ABC of oxygen: Hyperbaric oxygen therapy”; British Medical Journal; 

London: 1998. 

2. Tibbles and Edelsberg, “Hyperbaric Oxygen Therapy”; The New England Journal of 

Medicine; Massachusetts Medical Society: 1996. 

HBO2: Its Use and Appropriateness A-2 OEI-06-99-00090 
APPENDIX B 

Section 35-10 of the Coverage Instruction Manual 

[ 35-10 HYPERBARIC OXYGEN THERAPY 

For purposes of coverage under Medicare, hyperbaric oxygen (HBO) therapy is a modality in which the entire body is 

exposed to oxygen under increased atmospheric pressure. 

A. Covered Conditions. 

Program reimbursement for HBO therapy will be limited to that which is administered in a chamber (including the one 

man unit) and is limited to the following conditions: 

1. Acute carbon monoxide intoxication. 

2. Decompression illness. 

3. Gas embolism. 

4. Gas gangrene. 

5. Acute traumatic peripheral ischernia. HBO therapy is a valuable adjunctive treatment to be used in 

combination with accepted standard therapeutic measures when loss of function, limb, or life is threatened. 

6. Crush injuries and suturing of severed limbs. As in the previous conditions, HBO therapy would be an 

adjunctive treatment when loss of function, limb, or life is threatened. 

7. Progressive necrotizing infections (necrotizing fasciitis, meleney ulcer). 

8. Acute peripheral arterial insufficiency. 

9. Preparation and preservation of compromised skin grafts. 

10. Chronic refractory osteomyelitis, unresponsive to conventional medical and surgical management. 

11. Osteoradionecrosis as an adjunct to conventional treatment. 

The following uses of HBO are covered for services rendered on and after 10/1/82. 

12. Soft tissue radionecrosis as an adjunct to conventional treatment. 

13. Cyanide poisoning. 

The following use of HBO is covered for services rendered on or after 2/22/84 

14. Actinomycosis, only as an adjunct to conventional therapy when the disease process is refractory to 

antibiotics and surgical treatment. 

HBO2: Its Use and Appropriateness B-1 OEI-06-99-00090 
B. Noncovered Conditions 

No program payment may be made for HBO in the treatment of the following conditions: 

1. Cutaneous, decubitus, and stasis ulcers. 

2. Chronic peripheral vascular insufficiency. 

3. Anaerobic septicemia and infection other than clostridial. 

4. Skin burns (thermal). 

5. Senility. 

6. Myocardial infarction. 

7. Cardiogenic shock. 

8. Sickle cell crisis. 

9. Acute thermal and chemical pulmonary damage, i.e., smoke inhalation with pulmonary insufficiency. 

10. Acute or chronic cerebral vascular insufficiency. 

11. Hepatic necrosis. 

12. Aerobic septicemia. 

13. Nonvascular causes of chronic brain syndrome (Pick's disease, Alzheimer's disease, Korsakoffs disease). 

14. Tetanus. 

15. Systemic aerobic infection 

16. Organ transplantation, 

17. Organ storage. 

18. Pulmonary emphysema, 

19. Exceptional blood loss anemia 

20. Multiple Sclerosis, 

21. Arthritic Diseases. 

Effective for services rendered on or after September 6, 1984: 

22. Acute cerebral edema. 

HBO2: Its Use and Appropriateness B-2 OEI-06-99-00090 
C. Reasonable Utilization Parameters 

Make payment where HBO therapy is clinically practical. HBO therapy should not be a replacement for other 

standard successful therapeutic measures. Depending on the response of the individual patient and the severity of 

the original problem, treatment may range from less than 1 week to several months duration, the average being 2 to 

4 weeks. Review and document the medical necessity for use of hyperbaric oxygen for more than 2 months, 

regardless of the condition of the patient, before further reimbursement is made. 

D. Topical Application of Oxygen 

This method of administering oxygen does not meet the definition of HBO therapy as stated above. Also, its clinical 

efficacy has not been established. Therefore, no Medicare reimbursement may be made for the topical application 

of oxygen. (Cross refer: §35-31.) 

HBO2: Its Use and Appropriateness B-3 OEI-06-99-00090 
APPENDIX C 

Discussion of covered indications by Florida BC/BS 

1. Acute carbon monoxide intoxication induces hypoxic stress. The cardiac and central 

nervous systems are the most susceptible to injury from carbon monoxide. The 

administration of supplemental oxygen is essential treatment. Hyperbaric oxygen causes a 

higher rate of dissociation of carbon monoxide from hemoglobin than can occur breathing 

pure air at sea level pressure. The chamber compressions should be between 2.5 and 3.0 

atm abs. It is not uncommon in patients with persistent neurological dysfunction to 

require subsequent treatments within six to eight hours, continuing once or twice daily 

until there is no further improvement in cognitive functioning. 

2. Decompression illness arises from the formation of gas bubbles in tissue or blood in 

volumes sufficient enough to interfere with the function of an organ or to cause alteration 

in sensation. The cause of this enucleated gas is rapid decompression during ascent. The 

clinical manifestations range from skin eruptions to shock and death. The circulating gas 

emboli may be heard with a doppler device. Treatment of choice for decompression 

illness is HBO2 with mixed gases. The result is immediate reduction in the volume of 

bubbles. The treatment prescription is highly variable and case specific. The depths could 

range between 60 to 165 feet of sea water for durations of 1.5 to over 14 hours. The 

patient may or may not require repeat dives. 

3. Gas embolism occurs when gases enter the venous or arterial vasculature embolizing in a 

large enough volume to compromise the function of an organ or body part. This occlusive 

process results in ischemia to the affected areas. Air embolism may occur as a result of 

surgical procedures (e.g., cardiovascular surgery, infra-aortic balloons, arthroplasties, or 

endoscopies), use of monitoring devices (e.g., Swan-Ganz introducer, infusion pumps), in 

nonsurgical patients (e.g., diving ruptured lung in respirator-dependent patient, infection 

of fluids into tissue space), or traumatic injuries (e.g., gunshot wound, penetrating chest 

injuries). Hyperbaric oxygen therapy is the treatment of choice. It is most effective when 

initiated early. Therapy is directed toward reducing the volume of gas bubbles and 

increasing the diffusion gradient of the embolized gas. Treatment modalities range from 

high pressure to low pressure mixed gas dives. 

4. Gas gangrene is an infection caused by the clostridium bacillus, the most common being 

clostridium perfringens. Clostridial myositis and myonecrosis (gas gangrene) is an acute, 

rapidly growing invasive infection of the muscle. It is characterized by profound toxemia, 

extensive edema, massive death of tissue and variable degree of gas production. The most 

prevalent toxin is the alpha-toxin which in itself is hemolytic, tissue-necrotizing and lethal. 

The diagnosis of gas gangrene is based on clinical data supported by a positive [gramstained] smear obtained from tissue fluids, X-ray radiographs, if obtained, can visualize 

tissue gas. 

The onset of gangrene can occur one to six hours after injury and presents with severe and 

sudden pain at the infected area. The skin overlying the wound progresses from shiny and 

tense, to dusky, then bronze in color. The infection can progress as rapidly as six inches 

per hour. Hemorrhagic vesicles may be noted. A thin, sweet-odored exudate 

HBO2: Its Use and Appropriateness C-1 OEI-06-99-00090 
is present. Swelling and edema occur. The noncontractile muscles progress to dark red to 

black in color. 

The acute problem in gas gangrene is to stop the rapidly advancing infection caused by 

alpha-toxin and to continue treatment until the advancement of the disease process has 

been arrested. The goal of HBO2 therapy is to stop alpha-toxin production thereby 

inhibiting further bacterial growth at which point the body can use its own host defense 

mechanisms. HBO2 treatment starts as soon as the clinical picture presents and is 

supported by a positive gram-stained smear. A treatment approach utilizing HBO2, is 

adjunct to antibiotic therapy and surgery. Initial surgery may be limited to opening the 

wound. Debridement of necrotic tissue can be performed between HBO2 treatments 

when clear demarcation between dead and viable tissue is evident. The usual treatment 

consists of oxygen administered at 3.0 atm abs pressure for 90 minutes three times in the 

first 24 hours. Over the next four to five days, treatment sessions twice a day are usual. 

The sooner HBO2 treatment is initiated, the better the outcome in terms of life, limb and 

tissue saving. 

5. Crush injuries and suturing of severed limbs, acute traumatic peripheral ischemia 

(ATPI), and acute peripheral arterial insufficiency: Acute traumatic ischemia is the 

result of injury by external force or violence compromising circulation to an extremity. 

The extremity is then at risk for necrosis or amputation. Secondary complications are 

frequently seen: infection, non-healing wounds, and non-united fractures. 

The goal of HBO2 therapy is to enhance oxygen at the tissue level to support viability. 

When tissue oxygen tensions fall below 30 mmHg., the body’s ability to respond to 

infection and wound repair is compromised. Using HBO2 at 2-2.4 atm, the tissue oxygen 

tension is raised to a level such that the body’s responses can become functional again. 

The benefits of HBO2 for this indication are enhanced tissue oxygenation, edema 

reduction and increased oxygen delivery per unit of blood flow thereby reducing the 

complication rates for infection, nonunion and amputation. 

The usual treatment schedule is three 1.5 hour treatment periods daily for the first 48 

hours. Additionally, two 1.5 hour treatment session daily for the next 48 hours may be 

required. On the fifth and sixth days of treatment, one 1.5 hour session would typically be 

utilized. At this point in treatment, outcomes of restored perfusion, edema reduction and 

either demarcation or recovery would be sufficient to guide discontinuing further 

treatments. 

For acute traumatic peripheral ischemic, crush injuries and suturing of severed limbs, 

Hyperbaric Oxygen Therapy is a valuable adjunctive treatment to be used in combination 

with accepted standard therapeutic measures, when loss of function, limb, or life is 

threatened. Arterial insufficiency ulcers may be treated by HBO2 therapy if they are 

persistent after reconstructive surgery has restored large vessel function. 

6. The principal treatment for progressive necrotizing infections (nectrotizing fasciitis, 

meleney ulcer) is surgical debridement and systemic antibiotics. HBO2 is recommended 

as an adjunct only in those settings where mortality and morbidity are expected to be high 

despite aggressive standard treatment. One of the necrotizing infections, Meleney’s ulcer, 

is a polymicrobial (mixed aerobic-anaerobic organisms) ulcer which slowly progresses 

affecting the total thickness of the skin. Also called a bacterial synergistic gangrene, the 

Meleney ulcer is associated with the formation of burrowing cutaneous fissures and sinus 

tracts that emerge at distant skin sites. This ulcer presents as a wide 

HBO2: Its Use and Appropriateness C-2 OEI-06-99-00090 
area of pale red cellulitis that typically with a central area of granulation tissue encircled by 

gangrenous or necrotic tissue. 

Another type of progression necrotizing infection is necrotizing fasciitis. This condition is 

a relatively rare infection. It is usually a result of a group A streptococcal infection 

beginning with severe or extensive cellulitis that spreads to involve the superficial and 

deep fascia, producing thrombosis of the subcutaneous vessels and gangrene of the 

underlying tissues. A cutaneous lesion usually serves as a portal of entry for the infection, 

but sometimes no such lesion is found. 

7. Preparation and preservation of compromised skin grafts utilizes HBO2 for graft or 

flap salvage in cases where hypoxia or decreased perfusion have compromised viability. 

HBO2 enhances flap survival. Treatments are given at a pressure of 2.0 to 2.5 atm abs 

lasting from 90-120 minutes. It is not unusual to receive treatments twice a day. When 

the graft or flap appears stable, treatments are reduced to daily. Should a graft or flap fail, 

HBO2 may be used to prepare the already compromised recipient site for a new graft or 

flap. It does not apply to the initial preparation of the body site for a graft. HBO2 

therapy is not necessary for normal, uncompromised skin grafts or flaps. 

8. Chronic refractory osteomyelitis persists or recurs following appropriate interventions. 

These interventions include the use of antibiotics, aspiration of the abscess, immobilization 

of the affected extremity, and surgery. The Undersea and Hyperbaric Medical Society 

have defined “chronic” as existing six months or more. HBO2 is an adjunctive therapy 

used with the appropriate antibiotics. Antibiotics are chosen on the basis of bone culture 

and sensitivity studies. HBO2 can elevate the oxygen tensions found in infected bone to 

normal or above normal levels. This mechanism enhances healing and the body’s 

antimicrobial defenses. It is believed that HBO2 augments the efficacy of certain 

antibiotics (gentamicin, tobramycin, and amikacin). Finally, the body’s osteoclast function 

of removing necrotic bone is dependent on a proper oxygen tension environment. HBO2 

provides this environment. HBO2 treatments are delivered at a pressure of 2.0 to 2.5 atm 

abs for a duration of 90-120 minutes. It is not unusual to receive daily treatments 

following major debridement surgery. The number of treatments required vary on an 

individual basis. Medicare Part B can cover the use of HBO2 for chronic refractory 

osteomyelitis that has been demonstrated to be unresponsive to conventional medical and 

surgical management. 

9. HBO2’s use in the treatment of osteoradionecrosis and soft tissue radionecrosis is one 

part of an overall plan of care. Also included in this plan of care are debridement or 

resection of non-viable tissues in conjunction with antibiotic therapy. Soft tissue flap 

reconstruction and bone grafting may also be indicated. HBO2 treatment can be indicated 

both preoperatively and postoperatively. 

The patients who suffer from soft tissue damage or bone necrosis present with disabling, 

progressive, painful tissue breakdown. They may present with wound dehiscence, 

infection, tissue loss and graft or flap loss. The goal of HBO2 treatment is to increase the 

oxygen tension in both hypoxic bone and tissue to stimulate growth in functioning 

capillaries, fibroblastic proliferation and collagen synthesis. The recommended daily 

treatments last 90-120 minutes at 2.0 to 2.5 atm abs. The duration of HBO2 therapy is 

highly individualized. 

10. Cyanide poisoning carries a high risk of mortality. Victims of smoke inhalation 

frequently suffer from both carbon monoxide and cyanide poisoning. The traditional 

HBO2: Its Use and Appropriateness C-3 OEI-06-99-00090 
 antidote for cyanide poisoning is the infusion of sodium nitrite. This treatment can 

potentially impair the oxygen carrying capacity of hemoglobin. Using HBO2 as an adjunct 

therapy adds the benefit of increased plasma dissolved oxygen. HBO2’s benefit for the 

pulmonary injury related to smoke inhalation remains experimental. The HBO2 treatment 

protocol is to administer oxygen at 2.5 to 3.0 atm abs for up to 120 minutes during the 

initial treatment. 

Most patients with combination cyanide and carbon monoxide poisoning will receive only 

one treatment. 

11. Actinomycosis is a bacterial infection caused by Actinomyces israelii. Its symptoms 

include slow growing granulomas that later breakdown, discharging viscid pus containing 

minute yellowish granules. The treatment includes prolonged administration of antibiotics 

(penicillin and tetracycline). Surgical incision and draining of accessible lesions is also 

helpful. Only after the disease process has shown refractory to antibiotics and surgery, 

should HBO2 be covered by Medicare Part B. 

**Note that some of the 14 indications covered by CIM 35-10 are grouped into broader 

categories. 

HBO2: Its Use and Appropriateness C-4 OEI-06-99-00090 
APPENDIX D 

Appropriateness of Treatment 

Appropriateness of Treatment (in % beneficiaries and total dollars) 

Class % SE (+/-) 

ESTIMATED 

ALLOWED 

CHARGES 

(millions) 

INTERVAL 

95% CONFIDENCE 

(millions) 

INAPPROPRIATE 31.6 3.0 $14.2 $12.5 to $16.0 

EXCESSIVE* 7.3 1.2 $4.9 $3.3 to $6.4 

QUESTIONABLE 

QUALITY 20.2 2.55 $11.1 $9.7 to $12.6 

APPROPRIATE 40.9 3.1 $19.7 $17.9 to $21.5 

TOTAL 100 N/A $49.9 N/A 

*Dollars associated with excessive treatments include only the amount that was considered excessive, the 

remainder of the associated monies are included under the categories ‘questionable quality’ or ‘appropriate’. 

Variables determining Appropriateness of Treatment 

Class 

(in % beneficiaries and total dollars) 

N=378* 

% SE (+/-) 

ESTIMATED 

ALLOWED 

CHARGES 

( millions) 

INTERVAL 

95% CONFIDENCE 

(millions) 

NO PROBLEM* 40.9 3.1 $18.8 $17.2 to $20.5 

NO HBO2* 9.2 2.0 $3.7 $2.6 to $4.8 

NOT CONSISTENT 

WITH 35-10* 22.4 2.6 $10.5 $9.1 to $11.9 

EXCESSIVE 

TREATMENT* 12.9 1.7 $3.3 $2.2 to $4.3 

TREATMENT 

BEYOND PLATEAU* 10.9 1.6 $2.7 $1.8 to $3.7 

INADEQUATE 

TESTING* 20.0 2.5 $10.5 $9.3 to $11.8 

INSUFFICIENT 

JUSTIFICATION OF 

CONTINUATION* 

38.0 3.0 $19.6 $17.9 to $21.3 

*Categories are not necessarily mutually exclusive. The proportion and dollars represent all beneficiaries whereas 

the first table above is prioritized (mutually exclusive) such that if a beneficiary’s treatment was inappropriate, it was 

not included when considering excessive treatments or excessive quality care. 

HBO2: Its Use and Appropriateness D-1 OEI-06-99-00090 
APPENDIX E 

Accepted Usage of HBO2 by HCFA and Interest Groups

Condition HCFA UHMS ACHM International 

Bubbles 

Decompression Illness Yes Yes Yes Yes 

Gas Embolism Yes Yes Yes Yes 

Poisoning 

Acute Carbon Monoxide Intoxication Yes Yes Yes Yes 

Cyanide Poisoning Yes Yes Yes Yes 

Hydrogen Sulfide Poisoning No No No Yes 

Carbon Tetrachloride Poisoning No No No Yes 

Infections 

Clostridial Myonecrosis (Gas Gangrene) Yes Yes Yes Yes 

Progressive Necrotizing Infection Yes Yes Yes Yes 

Chronic Refractory Osteomyelitis Yes Yes Yes Yes 

Meleney’s Ulcer Yes Yes Yes Yes 

Actinomycosis Yes No Yes Yes 

Refractory Mycoses No No No Yes 

Leprosy No No No Yes 

Plastics 

Problem Wounds No Yes Yes Yes 

Acute Peripheral Arterial Insufficiency Yes No Yes Yes 

Compromised Skin Grafts Yes Yes Yes Yes 

Thermal Burns No Yes Yes Yes 

Aid to Re-Implantation Surgery No Yes No Yes 

Traumatology 

Acute Traumatic Peripheral Ischemia Yes Yes Yes Yes 

Crush Injury and Suturing of Severed Limbs Yes Yes Yes Yes 

Compartment Syndrome Yes Yes Yes Yes 

Soft tissue Sports Injuries No No No Yes 

HBO2: Its Use and Appropriateness E-1 OEI-06-99-00090 
Condition HCFA UHMS ACHM International 

Orthopedics 

Osteoradionecrosis Yes Yes Yes Yes 

Soft-tissue Radionecrosis Yes Yes Yes Yes 

Nonunion of Fractures No No No Yes 

Bone Grafts No No No Yes 

PVD-1 

Diabetic Wounds No Yes Yes Yes 

Ischemic Gangrene (Related) No Yes Yes Yes 

Leg Pain No No No Yes 

PVD - 2 

Shock No No No Yes 

Myocardial Ischemia No No No Yes 

Aid to Cardiac Surgery No No No Yes 

Neurological 

Stroke No No No Yes 

Multiple Sclerosis No No No Yes 

Migraine No No No Yes 

Cerebral Edema No No No Yes 

Multi-infract Dementia No No No Yes 

Spinal Cord Injury No No No Yes 

Vascular Diseases of the Spinal Cord No No No Yes 

Intra cranial Abscess No Yes No Yes 

Peripheral Neuropathy No No No Yes 

Radiation Myelitis No No No Yes 

Vegetative Coma No No No Yes 

Hematology 

Sickle Cell Crises No No No Yes 

Severe Blood Loss Anemia No Yes No Yes 

HBO2: Its Use and Appropriateness E-2 OEI-06-99-00090 
Condition HCFA UHMS ACHM International 

Opthamology 

Occlusion of Central Artery of Retina No No No Yes 

Gastro-intestinal 

Gastric Ulcer No No No Yes 

Necrotizing Enterocolitis No No No Yes 

Paralytic Ileus No No No Yes 

Pneumotiodes Cystoides Intestinalis No No No Yes 

Hepatitis No No No Yes 

Enhancement of Radiosensitivity of Malignant Ulcers 

Enhancement of Radiosensitivity No No No Yes 

Otorhinolaryngology 

Sudden Deafness No No No Yes 

Acute Acoustic Trauma No No No Yes 

Labyrithitis No No No Yes 

Meniere’s Disease No No No Yes 

Malignant Otitis Externa No No No Yes 

Lung Disease 

Lung Abscess No No No Yes 

Pulmonary Embolism No No No Yes 

Endocrines 

Diabetes No No No Yes 

Obstetrics 

Complicated Pregnancy - Diabetes No No No Yes 

Congenital Heart Disease of the Neonate No No No Yes 

Heart Disease No No No Yes 

Placental Hypoxia No No No Yes 

Fetal Hypoxia No No No Yes 

Asphyxiation 

Drowning No No No Yes 

Near Hanging No No No Yes 

Smoke Inhalation No No No Yes 

HBO2: Its Use and Appropriateness E-3 OEI-06-99-00090 
Condition HCFA UHMS ACHM International 

Aid to Rehabilitation 

Spastic Hemiplegia of Stroke No No No Yes 

Paraplegia No No No Yes 

Chronic Myocardial Insufficiency No No No Yes 

Peripheral Vascular Disease No No No Yes 

HBO2: Its Use and Appropriateness E-4 OEI-06-99-00090 
APPENDIX F 

Comparison of ICD-9 Interpretations (HCFA vs. several LMRPs) 

Category ICD-9 HCFA 

Proposal 

TEXAS 

BC/BS* 

FLORIDA 

BC/BS 

Transamerica 

Southern CA 

AR (LA) 

BC/BS 

Date 7/97 10/97 4/98 3/97 1/99 

Carbon 

Monoxide 

Poison 

986 YES YES YES YES YES 

Decompression 

Sickness 993.3 YES YES YES YES YES 

Arterial Gas 

Embolism 993.9 

958.0 

999.1 

996.7-996.79 

NO 

YES 

NO 

NO 

NO 

YES 

NO 

NO 

YES 

YES 

NO 

NO 

NO 

YES 

NO 

NO 

YES 

YES 

YES 

YES 

Gas Gangrene 

040.0 YES YES YES YES YES 

Crush Injuries 

and Severed 

Limbs 

906.4 

925.0 

925.1-925.9 

926 

927.00-927.03 

927.04-927.08 

927.09-927.11 

927.12-927.19 

927.20-927.21 

927.22-927.79 

927.8-927.9 

928.00-928.01 

928.02-928.09 

928.10-928.11 

928.12-928.19 

928.2-928.21 

928.22-928.29 

928.3 

928.4-928.7 

928.8-928.9 

929.0 

929.1-929.8 

929.9 

996.90-996.99 

NO 

NO 

YES 

NO 

NO 

NO 

YES 

NO 

YES 

NO 

YES 

YES 

NO 

YES 

NO 

YES 

NO 

YES 

NO 

YES 

YES 

NO 

YES 

NO 

NO 

NO 

NO 

NO 

YES 

NO 

YES 

NO 

YES 

NO 

YES 

YES 

NO 

YES 

NO 

YES 

NO 

YES 

NO 

YES 

YES 

NO 

YES 

NO 

NO 

NO 

NO 

NO 

YES 

YES 

YES 

NO 

YES 

NO 

YES 

YES 

NO 

YES 

NO 

YES 

NO 

NO 

NO 

YES 

NO 

NO 

NO 

YES 

YES 

NO 

NO 

NO 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

NO 

NO 

NO 

NO 

NO 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

Progressive 

Necrotizing 

Infections 

686.0 

686.01 

686.09 

728.86 

785.4 

NO 

YES 

YES 

YES 

YES 

YES 

NO 

NO 

YES 

YES 

NO 

YES 

YES 

YES 

NO 

YES 

NO 

NO 

NO 

NO 

NO 

NO 

YES 

YES 

NO 

HBO2: Its Use and Appropriateness F-1 OEI-06-99-00090 
Category ICD-9 HCFA 

Proposal 

TEXAS 

BC/BS* 

FLORIDA 

BC/BS 

Transamerica 

Southern CA 

AR (LA) 

BC/BS 

Acute 

Traumatic 

Peripheral 

Ischemia 

900-902.52 

902.53 

903.01 

903.2 

904.0 

904.01-904.4 

904.41 

904.42-904.9 

443.9 

925-929 

991.1 

991.2 

NO 

YES 

YES 

YES 

YES 

NO 

YES 

NO 

YES 

PARTIAL 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

YES 

PARTIAL 

NO 

NO 

NO 

NO 

YES 

NO 

YES 

NO 

YES 

NO 

NO 

PARTIAL 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

YES 

PARTIAL 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

NO 

YES 

NO 

NO 

Arterial 

Insufficiency 250.7 

362.30-362.31 

443.81 

443.9 

444.0-444.20 

444.21 

444.22 

444.23-444.80 

444.81 

444.82-444.99 

733.41-733.49 

NO 

NO 

NO 

NO 

NO 

YES 

YES 

NO 

YES 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

YES 

YES 

NO 

YES 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

YES 

YES 

NO 

NO 

NO 

YES 

NO 

NO 

NO 

YES 

NO 

NO 

NO 

NO 

NO 

NO 

NO 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

NO 

Compromised 

Skin Grafts 996.52 

996.90-996.96 

YES 

YES 

YES 

NO 

YES 

NO 

YES 

NO 

YES 

NO 

Osteomyelitis 

730.10-730.19 YES YES YES YES YES 

ORN 

526.89 

909.2 

990 

YES 

NO 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

NO 

YES 

STRN 

990 

909.2 

YES 

NO 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

NO 

Cyanide 

987.7 

989.0 

YES 

YES 

NO 

NO 

YES 

YES 

NO 

YES 

YES 

YES 

Actinomycosis 

039.0-039.4 

039.5-039.7 

039.8 

039.9 

YES 

NO 

YES 

YES 

YES 

NO 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

YES 

* Texas Blue Cross/Blue Shield is now Trailblazers. 

HBO2: Its Use and Appropriateness F-2 OEI-06-99-00090 
APPENDIX G 

Key Questions From the Medical Review Protocol

N % S.E. Confidence 

95% 

Interval 

1. The ICD-9 codes billed to Medicare: 

A. Accurately Describe the Primary 

B. Approximate the Primary Indication 

C. Describe a Secondary or Tertiary Indication 

D. Seem Erroneous 

E. Other 

Total 

142 42.9 3.3 36.4 to 49.3 

80 21.7 2.6 16.6 to 26.8 

51 18.2 2.7 13.0 to 23.4 

47 13.1 2.2 8.8 to 17.5 

13 4.1 1.3 1.6 to 6.7 

333 

2. Did the physician establish a plan of care? 

A. Yes 

B. Yes, but inadequate 

C. Not documented 

Total 

154 45.6 3.2 39.2 to 52.0 

65 17.7 2.4 12.9 to 22.4 

121 36.7 3.2. 30.5 to 43.0 

340 

3. Did the physician establish objective 

progress measures? 

A. Yes 

B. Yes, but inadequate 

C. Not documented 

Total 

109 12.9 2.1 8.7 to 17.1 

49 55.1 3.2 48.8 to 61.5 

181 

339 

32.0 3.0 26.1 to 37.9 

4. Was sufficient progress to justify 

continuation noted in the medical 

A. Yes 

B. No 

Total 

177 55.2 3.3 48.6 to 61.7 

146 44.8 3.3 38.3 to 51.4 

323 

5. In your opinion, did treatments continue after 

benefits plateaued? 

A. Yes 

B. No 

C. Unable to determine 

Total 

73 13.2 1.8 9.6 to 16.8 

191 63.2 3.1 57.2 to 69.2 

75 23.6 2.8 18.1 to 29.1 

339 

6. Was physician attendance specifically 

documented in the chart? 

A. Always 

B. Sometimes 

C. Never 

Total 

101 27.5 2.9 21.9 to 33.1 

66 20.6 2.7 15.3 to 25.9 

171 51.7 3.3 45.3 to 58.1 

338 

Indication 

record? 

HBO2: Its Use and Appropriateness G-1 OEI-06-99-00090 
7. Does it appear that a physician was 

present? 

A. Yes 

B. No 

C. Unable to determine 

Total 

145 

135 

55 

335 

39.0 

44.1 

16.2 

3.1 

3.3 

2.4 

32.8 to 45.1 

37.8 to 50.5 

11.4 to 20.9 

8. Is there evidence that the physician was 

supervising treatments? 

A. Yes 

B. No 

C. Unable to determine 

Total 

207 

75 

52 

334 

58.8 

25.2 

16.1 

3.3 

2.9 

2.5 

52.4 to 65.2 

19.4 to 30.9 

11.2 to 20.9 

9. Did the patient receive appropriate testing for 

the diagnosis? 

A. Yes 

B. No 

C. Unable to determine 

Total 

223 

83 

33 

339 

67.2 

22.0 

10.8 

3.1 

2.7 

2.1 

61.2 to 73.2 

16.8 to 27.3 

6.7 to 14.8 

10. Was treatment prior to initial HBO2 

appropriate? 

A. Yes 

B. No 

C. Unable to determine 

Total 

212 

38 

88 

338 

63.0 

10.7 

26.3 

3.2 

2.1 

2.9 

56.8 to 69.2 

6.7 to 14.8 

20.6 to 32.0 

11. Was payment and coverage consistent 

with HCFA’s 35-10 guidelines? 

A. Yes 

B. No 

C. Unable to determine 

Total 

239 

84 

8 

331 

72.9 

25.6 

1.6 

2.9 

2.9 

0.6 

67.1 to 78.6 

19.9 to 31.3 

0.4 to 2.7 

HBO2: Its Use and Appropriateness G-2 OEI-06-99-00090 
APPENDIX H 

Agency Comments 

In this appendix, we present comments from the Health Care Financing Administration. 

HBO2: Its Use and Appropriateness H-1 OEI-06-99-00090 
HBO2: Its Use and Appropriateness H-2 OEI-06-99-00090 
HBO2: Its Use and Appropriateness H-3 OEI-06-99-00090 
HBO2: Its Use and Appropriateness H-4 OEI-06-99-00090