Assessing Selected Respiratory Therapy

Modalities: Trends and Relative Costs in the

Washington, D.C., Area

July 1981

NTIS order #PB82-101122
CASE STUDY #12

THE IMPLICATIONS OF

COST-EFFECTIVENESS

ANALYSIS OF

MEDICAL TECHNOLOGY

JULY 1981

BACKGROUND PAPER #2: CASE STUDIES OF

MEDICAL TECHNOLOGIES

CASE STUDY #12: ASSESSING SELECTED RESPIRATORY

THERAPY MODALITIES: TRENDS AND RELATIVE COSTS IN

THE WASHINGTON, D. C., AREA

Richard M. Scheffler, Ph. D.

Visiting Associate Professor of Health Economics

School of Public Health, University of California, Berkeley

Morgan Delaney, M.D.

Assistant Professor of Medicine, Department of Medicine

George Washington University Hospital, Washington, D.C.

OTA Background Papers are documents that contain information believed to be

useful to various parties. The information undergird formal OTA assessments or is

an outcome of internal exploratory planning and evaluation. The material is usually

not of immediate policy interest such as is contained in an OTA Report or Technical

Memorandum, nor does it present options for Congress to consider.
Library of Congress Catalog Card Number 80-600161

For sale by the Superintendent of Documents,

U.S. Government Printing Office, Washington, D.C. 20402
Foreword

This case study is one of 17 studies comprising Background Paper #2 for OTA’s

assessment, The Implicatiom of Cost-Effectiveness Analysis of Medical Technology.

That assessment analyzes the feasibility, implications, and value of using cost-effectiveness and cost-benefit analysis (CEA/CBA) in health care decisionmaking. The major, policy-oriented report of the assessment was published in August 1980. In addition

to Background Paper #2, there are four other background papers being published in

conjunction with the assessment: 1) a document which addresses methodological

issues and reviews the CEA/CBA literature, published in September 1980; 2) a case

study of the efficacy and cost-effectiveness of psychotherapy, published in October

1980; 3) a case study of four common diagnostic X-ray procedures, to be published in

summer 1981; and 4) a review of international experience in managing medical technology, published in October 1980. Another related report was published in

September of 1979: A Review of Selected Federal Vaccine and Immumnization Policies.

The case studies in Background Paper #2: Case Studies of Medical Technologies

are being published individually. They were commissioned by OTA both to provide

information on the specific technologies and to gain lessons that could be applied to

the broader policy aspects of the use of CEA/CBA, Several of the studies were specifically requested by the Senate Committee on Finance.

Drafts of each case study were reviewed by OTA staff; by members of the advisory panel to the overall assessment, chaired by Dr. John Hogness; by members of

the Health Program Advisory Committee, chaired by Dr. Frederick Robbins; and by

numerous other experts in clinical medicine, health policy, Government, and economics. We are grateful for their assistance. However, responsibility for the case studies remains with the authors.

I l l
Advisory Panel on The Implications of

Cost-Effectiveness Analysis of Medical Technology

John R. Hogness, Panel Chairman

President, Association of Academic Health Centers

Stuart H. Altman Sheldon Leonard

Dean Manager

Florence Heller School Regulatory Affairs

Brandeis University General Electric Co,

James L. Bennington

Chairman

Department of Anatomic Pathology and

Clinical Laboratories

Childrens Hospital of San Francisco

John D. Chase

Associate Dean for Clinical Affairs

University of Washington School of Medicine

Joseph Fletcher

Visiting Scholar

Medical Ethics

SChool of Medicine

University of Virginia

Clark C. Havighurst

Professor of Law

School of Law

Duke University

Barbara J. McNeil

Department of Radiology

Peter Bent Brigham Hospital

Robert H. Moser

Executive Vice President

American College of Physicians

Frederick Mosteller

Chairman

Department of Biostatistics

Harvard University

Robert M. Sigmond

Advisor on Hospital Affairs

Blue Cross and Blue Shield Associations

Jane Sisk Willems

VA Scholar

Veterans Administration
OTA Staff for Background Paper #2

Joyce C. Lashof, Assistant Director, OTA

Health and Life Sciences Division

H. David Banta, Health Program Manager

Clyde J. Behney, Project Director

Kerry Britten Kemp, * Editor

Virginia Cwalina, Research Assistant

Shirley Ann Gayheart, Secretary

Nancy L. Kenney, Secretary

Martha Finney, * Assistant Editor

Other Contributing Staff

Bryan R. Luce Lawrence Miike Michael A. Riddiough

Leonard Saxe Chester Strobel’

OTA Publishing Staff

John C. Holmes, Publishing Officer

John Bergling* Kathie S. Boss Debra M. Datcher

Patricia A. Dyson* Mary Harvey* Joe Henson
Preface

This case study is one of 17 that comprise

Background Paper #2 to the OTA project on the

Implications of Cost-Effectiveness Analysis of

Medical Technology. * The overall project was

requested by the Senate Committee on Labor

and Human Resources. In all, 19 case studies of

technological applications were commissioned

as part of that project. Three of the 19 were specifically requested by the Senate Committee on

Finance: psychotherapy, which was issued separately as Background Paper #3; diagnostic Xray, which will be issued as Background Paper

#5; and respiratory therapies, which will be included as part of this series. The other 16 case

studies were selected by OTA staff.

In order to select those 16 case studies, OTA,

in consultation with the advisory panel to the

overall project, developed a set of selection

criteria. Those criteria were designed to ensure

that

●

●

●

●

●

●

●

as a group the case studies would provide:

examples of types of technologies by function (preventive, diagnostic, therapeutic,

and rehabilitative):

examples of types of technologies by physical nature (drugs, devices, and procedures);

examples of technologies in different stages

of development and diffusion (new, emerging, and established);

examples from different areas of medicine

(such as general medical practice, pediatrics, radiology, and surgery);

examples addressing medical problems that

are important because of their high frequency or significant impacts (such as

cost );

examples of technologies with associated

high costs either because of high volume

(for low-cost technologies) or high individual costs;

examples that could provide informative

material relating to the broader policy and

methodological issues of cost-effectiveness

or cost-benefit analysis (CEA/CBA); and

● examples with sufficient evaluable literature.

On the basis of these criteria and recommendations by panel members and other experts,

OTA staff selected the other case studies. These

16 plus the respiratory therapy case study requested by the Finance Committee make up the

17 studies in this background paper.

All case studies were commissioned by OTA

and performed under contract by experts in academia. They are authored studies. OTA subjected each case study to an extensive review

process. Initial drafts of cases were reviewed by

OTA staff and by members of the advisory

panel to the project. Comments were provided

to authors, along with OTA’s suggestions for

revisions. Subsequent drafts were sent by OTA

to numerous experts for review and comment.

Each case was seen by at least 20, and some by

40 or more, outside reviewers. These reviewers

were from relevant Government agencies, professional societies, consumer and public interest

groups, medical practice, and academic medicine. Academicians such as economists and decision analysts also reviewed the cases. In all,

over 400 separate individuals or organizations

reviewed one or more case studies. Although all

these reviewers cannot be acknowledged individually, OTA is very grateful for their comments and advice. In addition, the authors of

the case studies themselves often sent drafts to

reviewers and incorporated their comments.

These case studies are authored works

commissioned by OTA. The authors are responsible for the conclusions of their specific case study. These cases are not statements of official OTA position. OTA does

not make recommendations or endorse particular technologies. During the various

stages of the review and revision process,

therefore, OTA encouraged the authors to

present balanced information and to recognize divergent points of view. In two cases,

OTA decided that in order to more fully

present divergent views on particular technologies a commentary should be added to

the case study. Thus, following the case
studies on gastrointestinal endoscopy and

on the Keyes technique for periodontal disease, commentaries from experts in the appropriate health care specialty have been

included, followed by responses from the

authors.

The case studies were selected and designed to

fulfill two functions. The first, and primary,

purpose was to provide OTA with specific information that could be used in formulating

general conclusions regarding the feasibility and

implications of applying CEA/CBA in health

care. By examining the 19 cases as a group and

looking for common problems or strengths in

the techniques of CEA/CBA, OTA was able to

better analyze the potential contribution that

these techniques might make to the management

of medical technologies and health care costs

and quality. The second function of the cases

was to provide useful information on the specific technologies covered. However, this was

not the major intent of the cases, and they

should not be regarded as complete and definitive studies of the individual technologies. In

many instances, the case studies do represent excellent reviews of the literature pertaining to the

specific technologies and as such can stand on

their own as a useful contribution to the field. In

general, though, the design and the funding

levels of these case studies were such that they

should be read primarily in the context of the

overall OTA project on CEA/CBA in health

care.

Some of the case studies are formal CEAs or

CBAs; most are not. Some are primarily concerned with analysis of costs; others are more

concerned with analysis of efficacy or effectiveness. Some, such as the study on end-stage

renal disease, examine the role that formal

analysis of costs and benefits can play in policy

formulation. Others, such as the one on breast

cancer surgery, illustrate how influences other

than costs can determine the patterns of use of a

technology. In other words, each looks at evaluation of the costs and the benefits of medical

technologies from a slightly different perspective. The reader is encouraged to read this study

in the context of the overall assessment’s objectives in order to gain a feeling for the potential

role that CEA/CBA can or cannot play in health

care and to better understand the difficulties and

complexities involved in applying CEA/CBA to

specific medical technologies.

The 17’ case studies comprising Background

Paper #2 (short titles) and their authors are:

Artificial Heart: Deborah P. Lubeck and John P.

Bunker

Automated Multichannel Chemistry Analyzers:

Milton C. Weinstein and Laurie A. Pearlman

Bone Marrow Transplants: Stuart O. Schweitzer and C. C. Scalzi

Breast Cancer Surgery: Karen Schachter and

Duncan Neuhauser

Cardiac Radionuclide Imaging: William B.

Stason and Eric Fortess

Cervical Cancer Screening: Bryan R. Luce

Cimetidine and Peptic Ulcer Disease: Harvey V.

Fineberg and Laurie A. Pearlrnan

Colon Cancer Screening: David M. Eddy

CT Scanning: Judith L. Wagner

Elective Hysterectomy: Carol Korenbrot, Ann

B. Flood, Michael Higgins, Noralou Roos,

and John P. Bunker

End-Stage Renal Disease: Richard A. Rettig

Gastrointestinal Endoscopy: Jonathan A. Showstack and Steven A. Schroeder

Neonatal Intensive Care: Peter Budetti, Peggy

McManus, Nancy Barrand, and Lu Ann

Heinen

Nurse Practitioners: Lauren LeRoy and Sharon

Solkowitz

Orthopedic Joint Prosthetic Implants: Judith D.

Bentkover and Philip G. Drew

Periodontal Disease Interventions: Richard M.

Scheffler and Sheldon Rovin

Selected Respiratory Therapies: Richard M.

Scheffler and Morgan Delaney

These studies will be available for sale by the

Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402.

Call OTA’s Publishing Office (224-8996) for

availability y and ordering information.
Case Study #12

Assessing Selected Respiratory Therapy

Modalities: Trends and Relative Costs in

the Washington, D. C., Area

Richard M. Scheffler, Ph.D.

Visiting Associate Professor of Health Economics*

School of Public Health

University of California, Berkeley

Morgan Delaney, M.D.

Assistant Professor of Medicine

Department of Medicine

George Washington University Hospital

Washington, D.C.

AUTHORS’ ACKNOWLEDGMENTS

We are grateful to Dr. Louise Russell of The Brookings Institution for helpful

comments on an earlier draft of this paper. We would also like to thank Lynn Herman

for her help in collecting and processing the data and Robert Friedland for his computer programing assistance.

● On leave from Department of Economics, George Washington University, Washington, D.C.
Contents

Page

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

RespiratoryTherapy: A Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

The Organization and Delivery of RespiratoryTherapyServices . . . . . . . . . . . . . . s

An Assessment of Respiratory Therapy Services . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 ,

OxygenTherapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Aerosol Therapy. .......,.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Physical Therapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Mechanical Aids to Lung Inflation, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

A Survey of Hospital-BasedRespiratory Therapy intheWashington, D.C., SMSA 10

Survey Methods and Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Survey Results: Hospital Utilization of Respiratory Therapy. . . . . . . . . . . . . . 11

Estimates of the Relative Costs of RespiratoryTreatment Modalities . . . . . . . . . . . 14

Conclusions and Implications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Appendix: Questionnaire Used in the Washington, D.C., SMSA Respiratory

Therapy Department Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .......;. . . . . . . . . . ~

LIST OF TABLES

Table No. Page

l. Utilization of Respiratory Therapy by Hospital Ownership, 1979. . . . . . . . . . . . 12

2. Utilization of Respiratory Therapy by Hospital Bed-Size, 1979. . . . . . . . . . . . . . 13

3. Trends in the Utilization of Four RespiratoryTherapyTreatment Modalities,

4.

5.

6.

1976-79 . . . . . . . . . . . . . . . . . . . . .: . ...;..... . . . . . . . . . . . . . . . . . . . . . . . 13

Personnel Used To Deliver Various Respiratory Therapy Treatrnent. . . . . . . . . 15

Modal Time Required by a Respiratory TherapistorTechnician To Deliver

Various Respiratory Therapy Treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 . .

Estimates of Relative Costs and Charges for Four RespiratoryTherapy Treatment

Modalities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l6
Case Study #12:

Assessing Selected Respiratory Therapy

Modalities: Trends and Relative Costs in

the Washington, D. C., Area

Richard M. Scheffler, Ph.D.

Visiting Associate Professor of Health Economics

School of Public Health

University of California, Berkeley

Morgan Delaney, M.D.

Assistant Professor of Medicine

Department of Medicine

George Washington University Hospital

Washington, D.C.

INTRODUCTION

There are data that suggest that some 25 to 30

percent of all patients admitted to hospitals in

the 1970’s received respiratory therapy.l Intermittent positive pressure breathing (IPPB)—the

active inflation of the lungs during inspiration

under positive pressure from a cycling valve—

was delivered to more than one-fourth of these

patients, making IPPB the single largest respiratory treatment modality (method of therapy)

(16). 2 Utilization of respiratory therapy in U.S.

hospitals has been estimated to have cost about

$700 million in 1975, or more than $1 billion in

1979 dollars (16).3

A lay person’s definition of the term respiratory therapy is presented in the next part of

this case study. Following that is a description

1According to Louise Russell (31 ), this compares to about 10 percent of all hospital admissions in 1961-62 and 19 percent in

1966-67.

‘From a national sample of 750 U.S. non-Federal short-term hospitals, about 8 percent of all hospital admissions received IPPB

(13).

3

The $1 billion estimates assumes the 1975 estimate made by

Russell (16) and adjusts it only for the average increase in medical

care prices over the 1975-79 period of about 4S percent.

of how the delivery of respiratory therapy is

currently organized in the hospital sector. Next

is presented a brief overview of selected respiratory therapy modalities, including an assessment, drawn from the available medical and

scientific literature, of what is known about the

efficacy or effectiveness of various respiratory

therapy procedures. 4 These procedures are divided into four basic categories: 1) oxygen therapy, 2) aerosol therapy, 3) physical therapy,

and 4) mechanical aids to lung inflation.

The descriptive material presented in this case

study is not a totally exhaustive or definitive

review of the literature. Certain topics are discussed in detail, while others are mentioned

only briefly. Special attention is paid to IPPB,

both because it is one of the most frequently per4We use the OTA definitions (28) of “efficacy” and “effectiveness. ” Efficacy: The probability of benefit to individuals in a defined population from a medical technology applied for a given

medical problem under ideal conditions of use. Effectiveness.

Same as efficacy except that it refers to . . . average conditions of

use.

3
4 . Background Paper #2: Case Studies of Medical Technologies

formed respiratory therapy procedures and because it has been one of the more controversial

ones. Evidence is presented that suggests that in

some instances IPPB may be substituted for by

alternate treatment modalities. Respiratory

therapy practices in the intensive care unit,

though an important area of involvement for

respiratory therapy personnel, are mentioned

only briefly.

The fifth part of this case study presents the

results of a survey we conducted of current respiratory therapy practices by hospitals in the

Washington, D. C., Standard Metropolitan Statistical Area (SMSA) during 1979. Particular

emphasis was placed on data concerning the use

of IPPB and other modalities which can potentially be substituted for IPPB. We were able to

obtain data on how often these different treatments were being delivered in the hospitals

located in the Washington, D. C., SMSA, and

were also able to discern a significant change in

the pattern of usage over the past several years.

Using the information we collected about the

time needed to deliver different types of respiratory therapies, the wages paid to respiratory

personnel, and the cost of equipment, in the

sixth part of this study, we estimate the relative

cost of delivering specific types of treatments.

We then compare differences in the relative

costs of treatments that can be substituted for

one another. Finally, we compare the estimated

relative costs to the actual charges for hospitals

in our survey.

Our analysis presented below supports the

conclusion that for some medical indications,

alternative treatment modalities, when compared to IPPB, could be delivered at a lower

relative cost. Data on efficacy or effectiveness

were not collected in our survey. However, our

review of the medical literature suggests the

comparability of the medical outcomes for some

treatments. The implications of the results of

our analysis, along with their limitations, are

discussed in the concluding section of this study.

RESPIRATORY THERAPY: A DEFINITION

In general, the term respiratory therapy refers

to the medical treatment of a diseased lung. It

encompasses all nonsurgical efforts directed at

maintaining, improving, or restoring lung function. However, in actual use, the term refers

only to those therapeutic interventions carried

out by trained respiratory care personnel in accordance with a physician’s order. A recent definition of respiratory therapy is the followings

Respiratory therapy is an allied health specialty employed with medical direction in the treatment, management, control, diagnostic evaluation, and care of patients with deficiencies and

abnormalities of the cardiopulmonary system.

Respiratory therapy shall mean the therapeutic

use of the following: medical gases and administration apparatus, environmental control systems, humidification, aerosol, medications, ventilatory support, bronchopulmonary drainage,

‘This definition was approved in 1969 by the Board of Directors

of the American Association of Inhalation Therapists (renamed the

American Association for Respiratory Therapy in 1972) (8).

pulmonary rehabilitation, cardiopulmonary resuscitation, and airway management.

Therapeutic respiratory therapy interventions, as noted above, can be grouped into four

major categories: 1) oxygen therapy, 2) aerosol

therapy, 3) physical therapy, and 4) mechanical

aids to lung inflation. The various modalities

are defined in greater detail below. Individually

or in varying combination, these methods of

therapy are being used to treat almost any kind

of respiratory problem. They may be used in the

general medical and surgical wards, or used in

the intensive care unit, where they have been

refined into sophisticated and coordinated life

support measures. Their use is especially common in patients undergoing surgery involving

the chest or upper abdomen and in patients with

chronic obstructive bronchial tube diseases,

such as emphysema, chronic bronchitis, asthma, and bronchiectasis. Such diseases constituted the sixth leading cause of death in the

United States in the 1970’s (“16).
.

Case Study #12 Assessing Selected Respiratory Therapy Modalities Trends and Relative Costs in the Washington D C Area ● 5

THE ORGANIZATION AND DELlVERY OF

RESPIRATORY THERAPY SERVICES

Most U.S. hospitals have developed an organized respiratory therapy department staffed

by highly trained and usually certified paramedical personnel. The activities of the paramedical

staff are closely supervised by a physician, who

serves as the department’s medical director. The

growth of autonomous respiratory therapy departments within U.S. hospitals, in terms both

of total number and size of individual departments, has been substantial and rapid over the

past two decades.’ This growth may be attributed to a number of different factors, including

the following:

●

●

●

●

advances in engineering design since 1950

which have brought about the development

of new, highly sophisticated mechanical devices useful in the support of lung function,

e.g., mechanical ventilators (breathing machines) (37);

increases in the number of patients with

acute and chronic respiratory disease, who

require respiratory care (22);

the need to assure quality control of respiratory care services rendered, by means of

effective supervision and ongoing education of workers in the field; and

the overall increase in third-party reimbursement in the hospital sector, especially

by medicare and medicaid.

Respiratory therapy departments may be

staffed by personnel of varying levels of formal

training (10). A respiratory therapist is usually a

graduate of a 2-year hospital or community college program granting an associate degree,

which has been approved by the American Medical Association and which is designed to qualify him or her for the registry examination given

by the National Board of Respiratory Therapy.

By passing that examination, an individual

becomes a registered respiratory therapist

(R.R.T. ). A respiratory therapy technician completes a l-year hospital-based program combining a curriculum of basic respiratory sciences

and supervised clinical experience. By passing

the technician certification examination, the individual becomes a certified respiratory therapy

technician (C.R.T.T. ). Other personnel employed by respiratory therapy departments include aides, who are trained on the job, and individuals with nursing credentials (R.N. or

L.P.N. certification).

Despite the distinct differences in formal

training among these various types of personnel, the generic term respiratory therapist is

often used to refer to any individual involved in

the provision of technical respiratory care. The

emergence of a formal educational apparatus

with mechanisms for achieving professional

credentials is fairly recent, and partly because of

that, there is considerable blurring of professional role identities. Individuals with limited

formal training often possess many years of

practical experience which allow them to

assume roles at a higher level of responsibility

than their formal training would suggest.7

‘By 1976, virtually all large private, nonprofit hospitals (100

beds or more) had developed respiratory therapy departments

(31).

‘The recent report of the American Association of Respiratory

Therapists concerning job descriptions and salary levels served

amply to illustrate this confusion (6).

AN ASSESSMENT OF RESPIRATORY THERAPY SERVICES

The services offered by respiratory therapy efficacy of specific interventions are made on

departments can be conveniently grouped into the basis of the current medical literature. Since

four major categories: 1) oxygen therapy, 2) IPPB has been chosen as the major area of inaerosol therapy, 3) physical therapy, and 4) terest in this case study, more attention is

mechanical aids to lung inflation. Each of these directed to that than to any of the other inis briefly discussed below. Statements about the terventions.
6 ● Background paper #.2: Case Studies of Medical Technologws

Oxygen Therapy

The administration of therapeutic gases is one

of the more important functions of respiratory

therapy. The primary function of the lung is to

exchange gas between the atmosphere and the

blood (i.e, to take in oxygen and eliminate carbon dioxide (CO2

), the waste product of cell

metabolism). Many of the diseases that affect

the lung can impair its gas exchange capability,

resulting in a fall in the oxygen content of the

blood. 8 Whether a patient needs supplemental

oxygen to restore blood oxygen levels to normal

can usually be ascertained by measuring the gas

pressures in a sample of the patient’s blood. If

oxygen levels are too low, oxygen is administered to the patient and its supply adjusted by titrating (adjusting) the delivered oxygen concentration. In most instances, the indications for

delivery of supplemental oxygen are well established, and there is currently no real controversy concerning when it should be used. A

variety of simple devices to deliver varying concentrations of oxygen to a patient are available.

.

Oxygen therapy is one of the oldest of all respiratory therapy modalities, and its effectiveness was established quite early in the treatment

of a wide variety of lung diseases (10). Nevertheless, it is possible to identify some serious

problems relating to the misuse of oxygen. One

problem is that supplemental oxygen is sometimes administered without documentation that

the patient has inadequate oxygen in his or her

blood. This course of action would be appropriate only under special circumstances (e. g., in an

emergency or in the postoperative recovery

room). Another problem is that sometimes the

patient receiving oxygen is not adequately

monitored with respect to the achievement of

the desired therapeutic objective (i. e., correction

‘Lung dysfunction results not only from primary lung disease,

but also as a byproduct of diseases of other organs. Some degree of

lung dysfunction is seen in most hospitalized patients. Thus, oxygen therapy is used by a high percentage of patients who are admitted to a hospital. The need for standardization and coordination of equipment used in oxygen therapy originally led to the development of respiratory therapy departments. Respiratory therapists have usual] y been assigned the role of sampling arterial blood

to assess its gas contents, then reporting these results to the medical team caring for the patient so that appropriate modifications

can be made in the amount of oxygen being given to a patient.

of the oxygen-deficient state). Sometimes the

patient will be given too much oxygen, exposing

him or her to potential toxic effects of an overdose of this drug (for indeed, oxygen should be

regarded as a drug). Occasionally, a patient is

given supplemental oxygen solely because it

makes him or her “feel better. ” The issue of psychological benefits v. more objective therapeutic improvements derived from a specific

treatment modality is difficult to assess when

discussing the “scientific” efficacy of a therapy.

Quite apart from the issues surrounding the

misuse of oxygen therapy, it should be noted

that additional scientific studies are needed

to define more accurately the short- and longterm toxic effects of oxygen when given to patients in higher concentrations than we normally breathe (26).

Aerosol Therapy

An aerosol is a suspension of very fine particles of a liquid or solid in a gas (e.g., the fog

seen on a damp morning is a suspension of

water droplets in the air). As such, an aerosol

can be breathed into the respiratory tract, where

the particles may be deposited and retained.

Therapeutic aerosols consist of either water

droplets or fine particles of medication added to

the inspired air for deposition onto the surface

of the lung. Humidity (aerosol of water) and

other aerosols are used to achieve four general

objectives (10):

●

●

●

●

humidification of the respiratory tract,

“wetting” of respiratory tract secretions

(mucus) so that they can be coughed up

more easily,

delivery of bronchodilator drugs which

dilate the breathing tubes, and

administration of antibiotics to treat bronchial infections.

Several mechanical devices, which are known

as nebulizers, are available to generate an

aerosol (i. e., put the particles of water or drug

into suspension). These range from a very simple device which depends on a jet of air to

create small particles from a liquid to complicated electronic machines, called ultrasonic

nebulizers, which create particles by vibrating
the liquid medium.9 The aerosol that is generated can be inhaled by the patient without mechanical assistance, or it can be forced into the

patient’s lungs under pressure by a pressurized

delivery device such as an IPPB machine. A patient requires instruction by a respiratory

therapist in the use of both nebulizers and pressurized delivery devices. Prior to each treatment, the therapist must add the fluid or medication which is to be nebulized to the device. In

general, the more complicated the nebulizer

used, the greater the degree of supervision required by a respiratory therapist while the patient is using the device. Special circumstances

(e.g., a weak or uncooperative patient) ma y

necessitate close supervision by a therapist of

every treatment.

There are currently many controversies relating to the clinical use of aerosol therapy. The

indications are not always clear cut, and the effectiveness of a treatment in any given patient

has not been satisfactorily defined by scientific

studies (26). Also controversial are the choice of

type of nebulizer and the need for an IPPB.

Many issues remain unresolved, e.g., whether

an expensive ultrasonic nebulizer is any more effective than a simple aerosol generator, and

whether an IPPB machine is necessary to deliver

an aerosol to patients who are breathing on

their own (33).

Physical Therapy

Physical therapy for patients with lung disease has two basic objectives:

• to facilitate the removal of secretions from

the lungs, and

● to improve the efficiency of breathing.

Among the physical measures employed are:

1) percussion (clapping) and vibration of the

thorax, 2) postural draining (positioning the patient so that secretions will drain toward the

mouth under the influence of gravity), and 3)

breathing exercises to teach a patient how to use

his or her respiratory muscles more efficiently.

‘For more detailed description of the technical aspects of the

various types of nebulizers, the reader should consult one of the

standard textbooks of respiratory care, e.g., that by Egan ( 10).

Although these procedures enjoy widespread

acceptance throughout the United States and the

world—indeed, many hospitals have established autonomous chest physiotherapy departments—there is a dearth of well-controlled

scientific evidence to support their effectiveness.

In many instances, a spontaneous cough could

yield the same amount of expectorated sputum

as the bronchial drainage procedures employed

by the chest physiotherapist (9). For example,

although chest physiotherapy is often routinely

ordered for patients with uncomplicated pneumonia, these patients are usually quite capable

of coughing themselves and can effectively clear

excess secretions from their respiratory tracts.

Few scientific studies have adequately demonstrated that chest physiotherapy aids patients in

the recovery from lung diseases (24). Many additional well-planned and well-controlled

studies will be necessary to answer the many

questions in this area.

Mechanical Aids to Lung Inflation

Mechanical aids to lung inflation are those

interventions used to support the ventilator

function of the respiratory system, This function—bulk movement of air from the environment through the breathing tubes to the gas- exchange membrane deep in the lungs—is normally accomplished by the bellows-like action of

the muscles of respiration acting upon the lungs.

A variety of mechanical ventilators which are

capable of pumping air into the lungs have been

developed. Most of them are electrically powered and generate positive pressure which forces

air into the lungs at rhythmic intervals.

If a patient’s breathing has totally ceased

owing to suppression of brain activity (e. g.,

following an overdose of sleeping pills), mechanical ventilator support is necessary to sustain the patient’s life. Mechanical ventilator

support may be similarly useful for patients

with paralysis of the respiratory muscles, chest

wall injury, and acute and potentially reversible

lung disease, such as extensive pneumonia or

smoke inhalation, Its effectiveness in these instances is well-accepted. Life support of a

critically ill patient requires a coordinated team
8 ● Background Paper #2 Case Studies of Medical Technologies

effort involving a physician, nurse, respiratory

therapist, and other paramedical personnel. The

patient is best monitored in an intensive care

unit where equipment and resources can be concentrated and made readily available. Most respiratory therapy departments are intimately involved in the delivery of critical care, and involvement in this area constitutes one of their

major activities. The most highly trained and

experienced therapists work in this area.

Some people have advocated the use of mechanical breathing machines for purposes other

than life support of critically ill patients. One of

these, mentioned in the discussion of aerosol

therapy above, is the use of an IPPB machine to

facilitate delivery of an aerosol into a patient’s

lungs. The acronym “IPPB” has now become

virtually synonymous with this use and is only

rarely used to refer to long-term continuous mechanical ventilator support. Thus, “IPPB treatment” refers to the use of a pressurized ventilator to deliver a gas with humidity and/or

other aerosols to a spontaneously breathing patient for periods of 10 to 20 minutes each, usually several times a day (1).

IPPB treatments have been one of the more

controversial areas in the respiratory field.

Therefore, a more detailed discussion of the

proposed indications for and the arguments

concerning the efficacy of IPPB is presented

below.

IPPB therapy has been based on the principal

assumption that the mechanical breathing machine will deliver a larger breath than the patient is able to take spontaneously with less

physical effort from the patient (17). Several objectives for the use of IPPB have been developed. These include (1):

●

●

improving the delivery of aerosol medications to those patients who are unable to

take a deep breath or whose pattern of

breathing is not regular;

improving the overall level of breathing

where it is inadequate to meet the body’s

metabolic requirements (i. e., when not all

the COZ is being excreted by the patient’s

lungs);

●

●

improving cough and expectoration of respiratory tract secretions (effective cough is

dependent on a deep inspiration prior to

the cough itself); and

preventing collapse of lung segments in patients who cannot take deep breaths (e.g.,

in the postoperative patients whose respirations are hindered by residual anesthetic

agents, drugs or medications, and pain).

Although these indications for the use of IPPB

are widely accepted, very few scientific data

have been collected to support its efficacy (38).

Moreover, IPPB therapy was introduced and

became widespread before its scientific validity

had been rigorously tested.

In 1974, the available information about

IPPB, as well as all other respiratory therapy

modalities, was reviewed at the Conference on

the Scientific Basis of Respiratory Therapy, held

at Sugarloaf, Pa. That 1974 conference was a

benchmark consensus conference sponsored by

the National Institutes of Health (NIH). Although it focused on an assessment of the efficacy of respiratory therapy in the treatment of

patients with stable chronic obstructive lung

disease, it also considered the overall use of respiratory therapy. Conferees judged the majority

of studies of clinical effectiveness of IPPB published up until that time to be inadequate investigations, often not well designed from a scientific or statistical standpoint (9), They also

recommended additional scientific studies that

would attempt to determine whether IPPB has

more than transient effects in any group of patients (29).

Since 1974, there have been a number of editorials and papers, many highly emotional, restating the IPPB controversy, but offering very

little new information (14,16,25). The total

number of investigations published every year

on the subject of IPPB has actually declined

(27). An attempt to draw conclusions from the

available studies of IPPB is difficult, because

many of the studies were not well-designed.

Many do not use comparable patient populations or methods of delivering IPPB (e.g.,

studies attempting to compare IPPB with alternative treatment modalities often use different
endpoints or outcomes as indicators of successful results).

For delivery of aerosol medications, IPPB has

been compared to a number of other delivery

modes. In seven of eight studies published since

1953, a simple nebulization device was found to

be just as effective as an IPPB machine in delivering an aerosol medication (12,13,15,21,23,

30,36); the eighth report found IPPB to be better

(34). Given this apparent similarity of efficacy

between devices, considerations other than efficacy might be used to dictate the choice of

treatment modality.

The evidence yielded by studies on the effectiveness of IPPB for improving the overall level

of ventilation (5,11,19,20,35) is difficult to

assess because of problems with the study designs. A review of the various studies suggests

that any improvement in ventilation brought

about by IPPB treatment is usually transient,

being essentially limited to the duration of the

treatment. One study found that the same level

of intermittent improvement in breathing could

be achieved if the patient were required to

voluntarily hyperventilate for several minutes

(33). At many hospitals, a routine of delivering

four approximately 20-minute treatments per

day has evolved. There is no satisfactory evidence to show that improving a patient’s breathing for 1 hour each day will have any significant

overall effect on that patient’s clinical course.

Few, if any, data exist on the issue of long-term

benefits (26).

A third accepted indication for IPPB use is in

the prevention of lung collapse, especially in the

postoperative period when the patient may not

be able to take deep breaths. However, the majority of studies fail to show measurable benefit

from this use of IPPB (3,4,32). For improving

lung inflation, IPPB has been compared in other

studies to two other mechanical devices: 1) blow

bottles (which require the patient to move water

from one bottle to another by generating high

pressures in the system when the patient blows

into it), and 2) the incentive spirometer (which

requires the patient to generate a negative pressure in the system by deep inspiration, thus raising a plastic ball in the vacuum created). Both of

these other devices have been claimed to be

more effective than IPPB in preventing postoperative lung collapse. One study found a

complication rate of 30 percent in patients

receiving IPPB, 15 percent in patients using the

incentive spirometer, and 8 percent in those using blow bottles (18). These results certainly

raise doubts about the continued exclusive use

of IPPB in the prevention of lung collapse,

Significant unanswered questions about the

efficacy of IPPB remain, and the need for more

scientific studies is great. Despite the overall

dearth of information, however, the evidence

we have reviewed suggests that IPPB may be no

more effective than various other treatment

modalities in achieving specific therapeutic

goals. In delivering a therapeutic aerosol to a

patient, an IPPB machine seems to be no more

effective than an ultrasonic nebulizer or a simple

aerosol generator. In preventing postoperative

lung collapse, IPPB would appear to be no more

effective than the simply designed incentive

spirometer.

A second Conference on the Scientific Basis of

Respiratory Therapy, sponsored by the National Heart, Lung, and Blood Institute of NIH,

was held in Atlanta, Ga., on November 14-16,

1979. The conference program was limited to a

discussion of in-hospital, nonintensive care

respiratory therapy. Intensive care respiratory

therapy was specifically excluded. Because of

the highly specialized equipment and techniques

employed in a total life support setting, intensive care respiratory therapy was regarded as

worthy of being the topic of a separate conference.

Conferees at the 1979 conference discussed a

broad array of topics under the same four

general categories which have been used in this

case study: oxygen therapy, aerosol therapy,

physical therapy, and mechanical aids to lung

inflation. Their reports sought to define what

was known and what was not known, and to

recommend what additional studies should be

undertaken. A brief overview of the 1979 Atlanta conference proceedings, which will be published in their entirety, is presented below.
In 1979, many issues highlighted by the 1974

Sugarloaf conference on respiratory therapy,

still remained unresolved. A recurring theme

throughout the 1979 conference was that the

lack of proof of a procedure’s efficacy does not

equate with no efficacy at all. Most procedures

have been empirically derived. Many have a

long history of use in the realm of folk medicine,

with at least subjective benefit derived by the

patient being treated. The application of rigid

scientific analysis to study the mechanism of

action and measurement of objective outcome

achieved by these procedures has come to the

forefront only within the past several decades.

Whether a procedure which is at least not harmful to the patient, and possibly quite beneficial,

should be withheld pending the final outcome of

scientific studies which may take many years to

complete to anyone’s satisfaction remains to be

answered.

The major issues regarding oxygen therapy in

1979 were basically the same issues discussed in

1974: misuse of the drug, effective monitoring

of its therapeutic success, and a need for better

understanding of its toxicities. Conferees noted

that the efficacy of the drug in relieving acute

hypoxemia (oxygen deficiency) is beyond dispute. However, with regard to chest physiotherapy measures, conferees noted, a great deal of

fundamental information concerning their effectiveness is lacking. There is a need to define

more precisely what the various techniques are

and to define standards for them (e. g., standards concerning the performance of chest vibration).

In the discussion of aerosol therapy, conferees

directed their attention to the lack of information about what constitutes an adequate aerosol

for penetration of the lung. The size of the

aerosol particle created may be of some importance. There is little information available on

A SURVEY OF HOSPITAL-BASED

WASHINGTON, D. C., SMSA

Survey Methods and Procedures

In order to estimate the relative costs of IPPB

the mechanism of action of aerosols at the cellular level and the effects aerosols bring about.

Additionally, it is not clear which parameters

can or should be measured to assess whether an

aerosol has had any effect. Until such knowledge has been accumulated, conferees suggested, no definitive conclusions can be drawn

about the choice of the device used to generate

an aerosol.

The final topic of discussion at the 1979 conference was mechanical aids to lung inflation.

Once again, the lack of basic information about

both the theory and practice pertaining to this

type of respiratory care was noted. To establish

the comparative efficacy of the various aids—

IPPB v. incentive spirometry v. deep breathing-

—conferees recommended additional studies

with standardized endpoints and precise definition of terms. They felt that the potential

benefits of such aids must be established before

meaningful cost-benefit studies could be undertaken.

Any attempt to draw overall conclusions

about whether respiratory therapy itself is efficacious is faced by formidable obstacles. Too

many pieces of scientific evidence are unavailable at this time. Conferees suggested that continued research in this area is clearly warranted.

Data we collected on the utilization of

selected respiratory therapy modalities among

the hospitals in Washington, D. C., SMSA in

1979 are presented in the next part of this case

study. The subsequent part contains our estimates of the relative costs of delivering an aerosol medication by three different devices: an

IPPB machine, an ultrasonic nebulizer, and a

simple aerosol generator, Also compared are the

relative costs of using an IPPB v. an incentive

spirometer to improve lung inflation.

RESPIRATORY THERAPY IN THE

and those treatment modalities which are potential substitutes, it was necessary for us to

develop a new data base including the utiliza-
tion of different treatment modalities, their

relative cost, and the personnel employed by

different sizes and types of hospitals. This information is not currently available for multiple

hospitals on a systematic basis. 10 We selected

as our geographic survey area the Washington,

D. C., SMSA. This SMSA has a population of

over 3 million (making it the seventh largest

SMSA in the United States), and it includes a

total of 56 hospitals.

Using the 1978 guide issue of the American

Hospital Association, we located each hospital

in the Washington, D. C., SMSA and recorded

data on hospital ownership, control, size (in

terms of number of beds), yearly admissions,

and occupancy rates. We then designed and pretested a questionnaire on seven sample hospitals. In the pretest, data were collected via

phone interviews with the technical directors

(chief therapists) of respiratory therapy units.

After the pretest, the questionnaire was revised and mailed to the technical or medical

director of the respiratory therapy department

at each of the 56 hospitals in the Washington,

D. C., SMSA. Of the 56 hospitals in the survey

universe, 43 provided some type of respiratory

therapy. These 43 hospitals were contacted between July and September of 1979. For the overall utilization data on respiratory therapy in

these hospitals, the response rate was about 60

percent. For some specific data items, the

response rate may have been lower. 12

Of the 43 hospitals that provide respiratory

therapy in the Washington, D. C., SMSA, 7 5

percent are private (60 percent private nonprofit, 15 percent private for-profit) and 25 percent are governmental (15 percent non-Federal

governmental and 10 percent Federal). Approximately 31 percent have some type of teaching

affiliation. Twenty-seven percent of the 43 hospitals surveyed have up to 150 beds, 15 percent

have 151 to 250 beds, 32 percent have 251 to 450

beds, and 26 percent have more than 450 beds. 13

In order to provide some time-trend data on

the utilization of four major treatment modalities used in delivering respiratory therapy, we

also conducted a special survey of five teaching

hospitals in the Washington, D. C., SMSA.

These hospitals provided data from their records for the 1976-79 period on the following

four modalities: 1) IPPB, 2) ultrasonic nebulization, 3) simple aerosol, and 4) incentive spirometry. These hospitals were large (averaging

over 600 beds) and all had some teaching affiliation.

Survey Results: Hospital Utilization of

Respiratory Therapy

The results of the survey of Washington,

D. C., SMSA hospitals shown in table 1 indicate

that 44 patients per 100 hospital admissions per

month received some type of respiratory therapy . On the average, for all reporting hospitals, 723 respiratory therapy treatments were

delivered per 100 hospital admissions. Governmental hospitals (Federal and non-Federal) delivered less than one-fourth the average number

of respiratory treatments per 100 admissions for

all reporting hospitals. A qualitative judgment

of the appropriateness of these different utilization rates is not possible without data on the

case mix and health status of the patient population treated. In part, the differences may reflect

factors such as lack of equipment or the quantity and training of the staff.

At private for-profit hospitals, IPPB was

delivered to 12 patients per 100 admissions,

about twice the average rate for all hospitals in

the sample. For all hospitals in the sample, an

average of 60 IPPB treatments were delivered

per 100 patient admissions. Private for-profit

hospitals, at 190 IPPB treatments per 100 patient admissions, were significantly above the

‘i’T[) our knowledge, t)ur data are the ~)nl}. sy~terna tlcally cL)l -

]ected data {ln the cost, c hdrge~ ut iilzati(ln, and per~(lnne[ used In

h(mpltal -bad retpl rat t~ry therapy departments.

‘‘ lJ5]ng “t and chi -squ~re te~ts on the average \Ize <)1 the h<)spltal and ownership of report]n~ and nt)nreportln~ ho~pltals w e

find n~l systematic bias.

12A statistical test 01 the r(’prc’sent~~t]ic’n[>s< ot each ~pec]tlc data

item was n t) t te~~ible WI t h I n t ht> I r-a mew(lrk (It ~)ur data c (l] lec t lo n
Table l.— Utilization of Respiratory Therapy by Hospital Ownership, 1979a (per 100 admissions per month)

Governmental Private

Federal Non-Federal Nonprofit For-profit All hospitals

Total patients treated with respiratory therapy . . . . . . . . . . . . . . 46 55b 4 1 – 44

N = 4 N = 2 N = 4 N = 1 N= 11

Total respiratory therapy treatments . . . . . . . . . . . . . . . . . . . . . . 153 180b

830 —c 723

N = 4 N = 2 N = 17 N = l N =24

IPPB patients. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3b 7 12 6

N = 3 N = 2 N = 19 N = 5 N =29

IPPB treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 27b 79 190 60

N = 4 N = 2 N =24 N = 7 N =37

Incentive spirometry patients . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 l 2 b 12 7 11

N = 3 N = 2 N = 19 N = 5 N =29

Chest physical therapy treatments. . . . . . . . . . . . . . . . . . . . . . . . 63 32b 130 130 66

N = 3 N = 2 N = 15 N = 5 N =25

N = numt)er O( responding hospitals

aBased on hospitals (n the Washington, D c , SMSA

bBeCause of the small number of observations In these cateaor(es, these data should be used With caut~on

clnsufflc lent obs.watlons

mean, followed by private nonprofits, at 79

treatments per 100, ” The number of IPPB

treatments delivered per 100 admissions at

Federal and non-Federal Government hospitals

was below the average for all hospitals in the

sample. Combining the data on the patients

treated with IPPB and the number of IPPB

treatments, we estimate that, on average, 10

IPPB treatments are given to each patient receiving IPPB. 17

Incentive spirometry was used by about 11

patients per 100 patient admissions, except at

private for-profit hospitals, where the figure

was 7 per 100 patient admissions. The number

of chest physical therapy treatments averaged

about 66 per 100 admissions, although Federal

and non-Federal Government hospitals had a

far lower utilization rate than private for-profit

and nonprofit hospitals.

Although the data in table 1 suggest differences between for-profit hospitals’ and other

hospitals’ patterns of usage of respiratory treatment modalities, the reasons for these differences are unclear .16 Many of the for-profit hospitals in the Washington, D. C,, SMSA are

small, do not have teaching affiliations, and

lack the equipment and staff necessary to de-

‘bin 1973, one study estimatecf the number of IPPB treatments to

be 236 per 100 patient admissions per month for 123 reporting hospitals (2).

t 7U5ua]ly, t his wc~uld mean I our treatments a day for 2 L z daYs,

I Hwe are ~ra tefu] tcl LCJU ise Russell of The Brookings Institution

for suggest ing this point.

liver respiratory therapy. For-profit hospitals

may have a somewhat different patient mix, and

the physicians ordering respiratory therapy

treatments in these institutions may not have

the benefit of consultation with lung specialists. ” Moreover, the indication for employing a

specific respiratory modality is rarely documented in the medical records. Respiratory therapy departments at these and other hospitals do

not document why specific treatments are given.

Table 2 shows the data we collected on the

utilization of respiratory therapy by hospitals of

different bed-size categories. It is interesting to

observe that hospitals with more than 450 beds

delivered about 25 IPPB treatments per 100 patient admissions, as compared to the average of

60 per 100 admissions for all hospitals in the

sample. Moreover, the percentage of patients

receiving IPPB treatments is inversely related to

hospital bed-size.20 Compared to the other hospitals in the sample, hospitals with 150 to 250

beds have more patients per 100 admissions receiving incentive spirometry (30 per 100 admissions), and less production of chest physical

therapy treatments.21

1 ~Moreover, some hospl ta]s contract out to private firms for respiratory services. This arrangement may also alter the pattern of

respirator y treatments performed.

ZOThe smallest hospita] had more than 330 beds and the largest

had 848 beds in 1979.

~lAgain, it shou]d be noted that without data on the severity of

illness of the mix of patients treated in hospitals of different sizes,

normative judgments concerning the appropriateness of the treatment are not possible.
Table 2.—Utilization of Respiratory Therapy by Hospital Bed-Size, 1979a (per 100 admissions per month)

Up to 150 150 to 250 250 to 450 >45 0

Total patients treated with respiratory therapy . . . . . . . . . . . . . .

Total respiratory therapy treatments . . . . . . . . . . . . . . . . . . . .

IPPB patients. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

IPPB treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Incentive spirometry patients . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chest physical therapy treatments. . . . . . . . . . . . . . . . . . . . . . . .

“beds beds beds beds All hospitals

18b 18b 52b 42 44

N = 2 N = 2 N = 3 N = 4 N = 11

720 842 710 760 723

N = 5 N = 5 N = 7 N = 6 N =23

13 12 6 6 6

N = 6 N = 6 N = 7 N = 8 N =27

105 105 111 25 60

N = 10 N = 7 N = 12 N = 8 N =37

15 30 9 10 12

N = 10 N = 5 N = 9 N = 5 N =29

43 27 54 107 66

N = 5 N = 6 N = 9 N = 5 N = 25

N = Number of responding hospitals b

because of the small number of observations In these categories, these data should be used With Caution

aBased on hospitals In the Washington DC SMSA

In order to make observations concerning any Table 3 shows trends from 1976 to 1979 in the

recent changes in the utilization of respiratory utilization by these five hospitals of four restherapy modalities, especially IPPB, we selected piratory treatment modalities: 1) IPPB, 2) ultraa sample of five teaching hospitals from the sonic nebulizer, 3) simple aerosol, and 4) incenuniverse of 43 hospitals in the Washington, tive spirometry. Of considerable interest is the

D. C., SMSA that delivered respiratory therapy dramatic reduction in the number of IPPB treatservices in 1979. These five teaching hospitals

are large, with an average bed-size of 626 beds,

and have an occupancy rate of about 82 percent.

Table 3.—Trends in the Utilization of Four Respiratory Therapy Treatment Modalities, 1976”79a

—

1976b1977b

IPPB treatment

Total IPPB treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121,772 111,990

IPPBs/ 100 admissions per month ., . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 100

IPPBs/bed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38.89 36.92

Ultrasonic nebulizer treatment

Total ultrasonic treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8,847 8,501.5

Ultrasonics/100 admissions per monthe

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 9

Ultrasonics/bede. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.65 3.66

Simple aerosol treatment

Total simple aerosol treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32,337 47,715

Simple aerosols/100 admissions per month . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 43

Simple aerosols/bed, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.33 15.73

Incentive spirometry treatment

Total incentive spirometry treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . — 8,543f

Spirometry treatments/100 admissions per monthg . . . . . . . . . . . . . . . . . . . . . — 18

Spirometry treatments/bed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 8.48

Incentive spirometry patients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . — —

incentive’spirometry patients/100 admissions per month . . . . . . . . . . . . . . . . — .

Incentive spirometry patients/bed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . — —

aBased on data from the followtng hospltals in the Washington D c SMSA

George Washington Unlversity Hospital, Holy Cross Hospital, Veterans Admlnlstratlon Hospital Fairfax Hospital and Washington Hospital Center

1976 1977 1978 1979

Average bed size 6262 6066 6066 6066

Average admissions/bed 358 3692 3692 3692

Occupancy rate 8274 8352 8352 8352

Census of hospital beds 2.539 2,498 2,498 2,498

We are assuming that the figures for 1978 and 1979 were the same as those for

1977

b

Full year statistlc

1978bc 1979c

50,698

45

16.72

36,418d

33d

12.o1d

2,350.5

3

1.01

91,088

81

30.03

13,240f

27

13.25

7,656h

0.12

2.69

2,976d

3d

1.29d

131 ,066d

117d

43.21d

16,1 38f

33

16.03

7,792 h

0.12

3.75

‘cWe are assuming the number of beds and admissions remains COn Skiflta!

1977 levels

d I g7g figures were estimated by doubllng the first 6 months statistics

‘Ultrasonic figures are comp!led from four hospitals

f~wo hospitals Supplledthis Stat lstlc

9For IWO hospitals reporting splrornetry, admissions = 48,746 and bed s

—-1,007, and for three hosp(tals reporting splrometry admusslons = 63,259

and beds = 2,076

hThree hospitals supplled this Stat lS!lC
14 ● Background Paper #2: Case Studies of Medical Technologies

ments per 100 admissions and per hospital bed

over the 1976-79 period. During that period, the

number of IPPB treatments per 100 admissions

declined about 70 percent (from 108 IPPB treatments in 1976 to an estimated 33 treatments in

1979). The number of ultrasonic treatments per

100 admissions declined about 75 percent (from

about 13 ultrasonic treatments in 1976 to 3

treatments in 1979). The number of simple aerosol treatments per 100 admissions in these hospitals increased from 1976 to 1979 over 300 percent (from 29 treatments to 117), and the number of incentive spirometry treatments per 100

admissions increased from 1977 to 1979 over

200 percent (from 18 treatments in 1977 to 33

treatments in 1979).22 23

22 The per bed comparisons are quite similar.

23Data demonstrating a similar dramatic decline in the frequency

of use of IPPB in selected hospitals were presented at the Atlanta

Conference on the Scientific Basis of Respiratory Therapy in November 1979. A survey from a 1,000-bed New York City Hospital

revealed a rapid decline since 1973. The Massachusetts General

Hospital witnessed marked decrease in use of IPPB since 1974.

Similar results have been observed at four unidentified Midwest

hospitals, Dr. Steven Ayers, professor and chairman of the Department of Medicine of St. Louis University, speaking on the

magnitude of use and cost of in-house respiratory care, said that a

national decline of approximately 70 percent had occurred in the

use of IPPB. (It should be recalled that the Sugarloaf Conference

on the Scientific Basis of Respiratory Therapy took place in 1974. )

ESTIMATES OF THE RELATIVE COSTS OF

RESPIRATORY TREATMENT MODALITIES

The significant decrease in the utilization of

IPPB and ultrasonic treatments and the increase

in utilization of simple aerosol and incentive spirometry treatments in five major teaching hospitals in the Washington, D. C., SMSA may represent important new trends in respiratory

therapy. One important reason for these trends

is that for some therapeutic indications these

different treatment modalities may well be substitutes for one another.24 In delivering a medication to a patient, a simple aerosol device has

been found to be as effective as an IPPB machine

(25). It seems quite likely that other substitutions among treatment modalities exist, but

documentation is currently limited.

Using data from our Washington, D. C.,

SMSA hospital survey, we estimated differences

in the relative cost of producing the following

respiratory treatment modalities: 1) IPPB, 2) ultrasonic nebulization, 3) simple aerosol. and 4)

incentive spirometry. 25 It was assumed for ou r

calculations that the effectiveness of these four

treatment modalities is equivalent, It was also

assumed that the amount of physician time reZqsee Burton, et a], (g)[or a discussion of some of these modalities.

ZsThe re]atlve cost estim,]tes include resource costs that differ

among treatment modalities, e.g., equipment and respiratory therapy personnel time. Thus, c,mts common to each treatment modality, such as overhead and the physician’s time used in ordering the

treatments, are not included.

quired for each modality is equal, because the

physician’s role is to select the appropriate treatment modality. For each of the four modalities,

the actual delivery of treatment to the patient is

the responsibility of different types and levels of

respiratory personnel. The delivery usually involves the time of a “therapist” and the use of

the needed equipment .26

In order to estimate relative costs, we first examined the types of personnel involved and the

amount of time required to deliver each of the

treatment modalities. As shown in table 4, for

three of the four modalities, about 70 percent of

the responding hospitals in our Washington,

D. C., SMSA survey reported that either a respiratory technician or therapist delivered the

treatment. For incentive spirometry, nearly 5 0

percent of the hospitals use either a therapist or

technician, and about 23 percent use a therapist

or a nurse. These data suggest that some hospitals use these different types of personnel somewhat interchangeably. For our relative cost estimates, it was assumed that there are no significant differences in the respiratory therapy personnel used for the four treatment modalities

under consideration, Table 5 shows the modal

amount of personnel time necessary to deliver

zbwe are assuming that the hosp] tal overhead allocated does not

differ significantly for ditferent equipment.
Case Study #12. Assessing Selected Respiratory Therapy Modalities Trends and Relative Costs in the Washington, D C A Area ● 15

four types of respiratory therapy treatments.27

It is clear that IPPB treatments require the

greatest amount of personnel time. For purposes

of our cost estimates, delivery time for each modality was assumed to be at the higher end of the

interval reported in table 5. The followup treatment time was assumed to be identical to the initial setup and treatment time.28 Since respiratory personnel appear to be used somewhat interchangeably by a significant number of hospitals in our survey, an average wage paid of

$12,000 per year was used for our calculations .29

Table 4.—Personnel Used To Deliver Various

Respiratory Therapy Treatments”

Frequency of Percentage of

response respondent s

IPPB treatment

Technician or therapist . . . . . . . . . . . 31 72.1 “/o

Therapist, . . . . . . . . . . . . . . . . . . . . . . 5 11.6

Technician . . . . . . . . . . . . . . . . . . 4 9.3

Therapist or nurse . . . . . . . . . . . . . 3 7.0

Ultrasonic nebulizer administration of a drug

Technician or therapist . . . . . . . . . . . 29 69.0

Therapist. . . . . . . . . . . . . . . . . . . . . . 6 11.9

Technician . . . . . . . . . . . . . . . . . . . . . 5 11.9

Therapist or nurse . . . . . . . . . . . . . . . . 2 4.8

Simple aerosol generator administration of a drug

Technician or therapist . . . . . . . . . . . 29 69.0

Therapist. . . . . . . . . . . . . . . . . . . . . . 5 11.9

Technician ... . . . . . . . . . . . . . . . . . 5 11,9

Therapist or nurse . . . . . . . . . . . . . . . . 2 4.8

Incentive spirometry treatment

Technician or therapist . . . . . . . . 21 48.8

Chest physical therapist . . . . . . . . . . . 1 2.3

Any nurse . . . . . . . . . . . . . . . . . . . . . . . 3 7.0

Therapist, . ... . . . . . . . . . . . . . 4 9.3

Technician . . . . . . . . . . . . . . . . . . . . 3 7.0

Therapist or nurse . . . . . . . . . . . . . 10 23.3

a~~ ~n

-

h o s pitals Irl the Washington, D C ~ SMSA

bBecause of mlsslng observations, totals may not equal 100 Percent

‘“The modal time was used instead of the mean, because the data

were not normal I y distributed.

Z~In many Instances, fo]]owup treatment will require less time.

Hence, the ct)st estimates of followup treatments may have an upm’a rd bias.

1“Thi+ wage tlgure is reported by the Bureau of Labor Statistics,

lr]dustry Wage Sur-Lvy, Washington, D. C., SMSA, September

1978 (7). The cost of fringe benefits would add about 20 percent to

these estimates. Obviously, as the mix of personnel changes or differs between hospitals, costs w1lI also change In a corresponding

manner,

Table 5.—Modal Time Required by a Respiratory

Therapist or Technician To Deliver Various

Respiratory Therapy Treatments’

Treatment modality Modal time in minutes

IPPB treatment . . . . . . . . . . . . . . . . . . . . 20-25

Ultrasonic nebulization of a medication 15-20

Aerosol medication treatment delivered

by a simple aerosol generator . . . . . . . 15

Instruction to patient for incentive

spirometer . . . . . . . . . . . . . . . . . . 10-15

aBased on hospitals In the Washington D c SMSA

We combined the cost of personnel time with

the cost of equipment to estimate the cost differentials between these four different treatment

modalities. First, we examined the personnel

and equipment costs for delivery of medication

or improving inflation of the lungs with an IPPB

machine. The various types of IPPB machines

currently sell for about $600 and have an expected life of 15 years. However, to be liberal in

our estimates, we depreciated the IPPB equipment costs in 7 years using a straight-line depreciation method. This produced a yearly cost of

about $85 per year, or about $0.14 per treatment. 30 There is also a one-time charge of about

$2.35 for disposable tubing to connect the patient to the machine. The machine is usually

powered by compressed air or oxygen, for

which we added a generous allowance of $1.00

per treatment. The personnel costs for IPPB are

about $2.90 for 25 minutes of personnel time.

The estimated cost for initial setup and treatment with IPPB, therefore, is about $6.40. 31 A

followup treatment would cost $4.05, because it

would include only the personnel, machine, and

the electricity y costs.

For the delivery of medication with an ultrasonic nebulizer, we estimate the following costs.

A nebulizer which currently costs $580 is assumed to depreciate over the same time span as

the IPPB machine. There also is a one-time

charge for each of the following disposable

‘“We used 25 treatments per week, which we calculated from the

survey data.

“Recall that this estimate is not the full cost of respiratory therapy, because overhead costs and the cost of physician’s time are

omitted Since the omitted costs are similar for the four treatment

methods, they do not affect the differences i n costs,
items: an ultrasonic cup, $2.00; tubing, $0.70;

mask, $0.60; and electricity costs, $1.00. 32 T h e

personnel costs for 20 minutes are about $200.

This produces a total cost of about $6.30 for an

initial setup and treatment. The followup treatment in most instances involves only the personnel, machine, and electricity costs, which

amount to $3.14.

Next, we estimate the personnel and equipment costs of delivering a medication by a simple aerosol generator. The equipment cost for

simple aerosol is $3.50, and the cost of 15

minutes of personnel time is $1.50, making the

total cost for the initial setup and treatment

about $5.00. For each followup treatment that

requires only personnel,33 the cost would be

only $1.50.

The costs for incentive spirometry to improve

lung inflation include the cost of the spirometer

itself, $8.60, and the cost of personnel time

needed to instruct and supervise the patient in

the spirometer’s use. This instruction and supervision takes an average of 15 minutes, at a personnel cost of approximately $1.50. This produces an initial treatment cost of $10.10. The

cost of a followup treatment is only $1.50 ,

assuming that personnel time is still required but

the same instrument is used. (Recall that these

relative cost estimates, as well as the others

presented, do not include the cost of the physician’s time or overhead since these costs are

common to all the treatment modalities. )

‘

z

The $1 cost of electricity is only a very rough estimate.

~JThls is the case i f the aerosol generator is reused.

The relative cost estimates shown in table 6

suggest that for initial treatment, incentive

spirometry has the highest relative cost, and

simple aerosol has the lowest. The relative costs

of the IPPB machine and the ultrasonic nebuIizer fall between these. Comparing the calculated relative costs for initial treatment to

hospital charges for initial treatment shows the

largest difference between costs and charges for

IPPB;

34 the next largest difference is for the

ultrasonic nebulizer.

Respiratory therapy patients usually require

multiple treatments, and the relative cost

estimates in table 6 suggest that for a followup

treatment, IPPB and the ultrasonic nebulizer

have the highest relative costs. The largest difference between the relative cost estimates and

hospital charges for a followup treatment is for

the simple aerosol; the next largest difference is

for the IPPB machine. For a followup treatment,

hospital charges are the highest for the IPPB

machine.

It is interesting to view these findings in the

light of recent trends in the utilization of different respiratory treatment modalities. As

noted in the previous part of this case study, at

five major teaching hospitals in the Washington, D. C., SMSA, the use of the IPPB machine

and the ultrasonic nebulizer is declining, while

the use of the incentive spirometer and the sim-

‘“These costs do not include the cost of physician’s time or hospital overhead costs.

Table 6.—Estimates of Relative Costs and Charges for Four Respiratory Therapy Treatment Modalities’ b

.—

Difference between costs -

costs Charges and charges

Initial Followup Initial Followup Initial Followup

Treatment modality treatment treatment treatment treatment treatment treatment

IPPB . . . . . . . . . . . . . . . . . . . . . $6.40 $ 4.04 $10.90 $8.90 $4.50 $4.86

Ultrasonic nebulizer . . . . . . . . . 6.44 3.14 10.70 6.60 4.26 3.60

Simple aerosol. . . . . . . . . . 5.00 1.50 8.70 6.90 3.70 5.40

Incentive spirometry. . . . . . . . . 10.10 1.50 13.10 6.10 3.00 4.60

scO~t~ l“~l”de onlY wages paid t.nonpflyslclanpersonneland equipment related costs and do not Include the cost of Phwclan’s time or hospital overhead Costs

The latter are assumed to be equal for the four treatments considered

bcharges are mean values reported from our survey of the hospitals m the Washwton. D C , SMSA
———

Case Study #12 Assessing Selected Respiratory Therapy Modalities Trends and Relative Costs in the Washington D. C , Area ● 17

ple aerosol generator is increasing. For purposes

of illustration, assume that half of the 70-

percent decrease over the 1976-79 period in

utilization of IPPB treatments per 100 hospital

admissions that we found in these hospitals

were replaced by utilization of simple aerosols

or incentive spirometry. For hospitals in the

Washington, D. C., SMSA, this change would

produce an estimated cost savings of about

CONCLUSIONS AND IMPLICATIONS

Over the past two decades, there has been

phenomenal growth in the United States in

respiratory therapy departments offering a

variety of treatment modalities aimed at improving lung dysfunction. These departments

offer four major types of therapy: 1) oxygen

therapy, 2) humidity and other aerosol therapy,

3) chest physiotherapy, and 4) mechanical aids

to lung inflation (including IPPB). In many instances, the increased use of these services has

occurred without much scientific evidence demonstrating that they bring about a measurable

improvement in the patient’s physical condition.

We have reviewed research findings on what

is known about the efficacy and effectiveness of

respiratory therapy modalities, emphasizing in

our review IPPB treatments delivered for several accepted therapeutic indications. Oxygen

therapy is the least controversial respiratory

therapy, because easily definable indications

and outcomes can be measured during the administration of supplemental oxygen. The values of aerosol therapy and chest physiotherapy

have not yet been scientifically demonstrated,

although specific uses have been shown to be

beneficial. The lack of scientifically demonstrated effectiveness is not proof that these therapies are not effective; it only indicates that we

currently do not know that they are effective.

IPPB treatments have enjoyed widespread acceptance for several therapeutic indications. For

all of these indications, the rationale underlying

the use of IPPB is the assumption that an IPPB

machine can deliver a larger breath to the pa-

$408,000 per year .35 To estimate other potential

savings would require more detailed data on the

substitution between different treatment modalities. Research on the substitutability of different respiratory treatment modalities should

receive a high priority.

“In making this calculation, we assumed that there was one initial setup cost per nine followup treatments.

tient with less work required of the patient. We

have found that there exists very little scientific

evidence to support the overall efficacy of IPPB.

Many studies that have compared IPPB to technologically less sophisticated devices (e. g., simple aerosols or incentive spirometers) have concluded IPPB is not more effective than the simpler alternative. To deliver an aerosol medication to a patient, for example, IPPB and a simple aerosol generator are comparable. In the

prevention of postoperative lung collapse, IPPB

treatments are at best comparable to the use of

an incentive spirometer.

Our analysis of data we collected on the hospitals in the Washington, D. C., SMSA showed

that the utilization of different respiratory

therapy treatment modalities varied substantially by type and size of hospital. Private for-profit

hospitals delivered more IPPB treatments and

fewer incentive spirometry treatments per 100

patient admissions than other hospitals; private

for-profit and nonprofit hospitals delivered over

twice the number of chest physical therapy

treatments per 100 patient admissions that Federal and non-Federal Government hospitals did.

As hospital size (number of beds) increased, the

number of respiratory therapy patients and

IPPB patients per 100 admissions declined.

However, before normative judgments on these

utilization differences can be made, the differences need to be related to the each hospital’s

case mix and the severity of illness of the patient

population treated in each hospital.

Our subsample of five teaching hospitals

showed dramatic changes in the use of certain
respiratory therapy treatments during the

1976-79 period. The utilization of IPPB and

ultrasonic treatment declined over 70 percent,

while utilization of incentive spirometry and

simple aerosol doubled. Although we did not

explore all the reasons for this change, it does

seem plausible that the 1974 Sugarloaf Conference on the Scientific Basis of Respiratory

Therapy and editorials in medical journals had

an impact on IPPB use in teaching hospitals.

What is surprising is the vast amount of flexibility that respiratory therapy departments appear to have and the speed at which changes in

treatment modalities can be accomplished.

According to our relative cost estimates,

changes away from the use of IPPB machines

and ultrasonic nebulizers toward the use of incentive spirometers and simple aerosol generators appear to be a move in the direction of selecting the least costly treatment modalities.

Our relative cost estimates also suggest that for

a followup treatment, an incentive spirometer

and a simple aerosol generator are substantially

less costly than an IPPB machine or an ultrasonic nebulizer. The move toward utilization of

less costly respiratory treatment modalities by

the hospitals in our subsample appears to have

occurred without Government regulation and

without any planning. As an illustration of a

possible cost savings, we estimated that the

substitution of simple aerosols or incentive spirometry for half the decrease in IPPB could produce yearly cost savings of about $400,000 for

the hospitals in the Washington, D. C., SMSA.

The validity of this assumption and the possibility of other cost-effective substitutions between

treatment modalities warrant further study.

Performing a rigorous cost-effectiveness analysis of respiratory therapy would involve the

use of a prospective random sample of patients

using different respiratory therapy treatment

modalities. Data on measurable health outcome

parameters and costs of the different therapies

would be required. The cost comparisons

should include all hospital costs related to the

treatment of the patient.
APPENDIX: QUESTIONNAIRE USED IN WASHINGTON, D. C.,

SMSA RESPIRATORY THERAPY DEPARTMENT SURVEY

Hospital Name

Medical Director

Technical Director

Additional Information

County

1. How many patients in toto were treated by your respiratory therapy

department last month?

2. How many total treatments/interventions were administered by your department

last month?

3.

4 .

5.

6 .

Are IPPB treatments administered in your hospital?

*If not, what other types of therapy have replaced IPPB treatments?

How many total IPPB treatments were administered last month?

How many different patients received IPPB therapy last month?

Is incentive spirometry available in your hospital?

7. How long has incentive spirometry been available at your hospital?

8. How many patients used incentive spirometry in the past month?

9. How many incentive spirometry treatments were administered last month?

10. What type(s) of incentive spirometer do you use?

a.

b.
20 ● Background Paper #.2: Case Studies of Medical Technologies

11. Who initiates the spirometry therapy?

Who follows up in the treatment?

For how many days is supervised therapy given?

How many times a

1 2 0 Is a charge made

day is supervised therapy given?

for each supervised use of the incentive spirometer or just

for the initial set-up?

13. What percent of treatments are administered by each of the

(% should total 100%)

Installations Ins. % Treatments

a. IPPB machine

b. Ultrasonic

nebulizer

c . Simple aerosol

generator

d. Other

14. How many chest physical therapy treatments do

following routes?

Treat %

you give p e r month?

1 5 . What is the amount of time required for one of your respiratory technicians

or therapists to perform each of the following interventions?

a. An IPPB treatment

b. Instruction to the patient about how to use an incentive

spirometer

c . Ultrasonic nebulization of a medication

d. Aerosol medication treatment delivered by a simple aerosol

generator

16. What is the charge to the patient for the following?

a . IPPB installation

b. IPPB treatment
Case Study #12 Assessing Selected Respirator.v Therapy Modalities: Trends and Relative costs In the Washington, D C Area ● 21

c .

d .

e.

f .

g“

h.

l.

j“

k.

Ultrasonic nebulization of a medication

Aerosol medication treatment delivered by a simple

aerosol generator

1P PB treatment with an aerosol of medication

Simple aerosol medication installation

Simple aerosol medication treatment

Blow bottle installation

Blow bottle treatment

Incentive spirometry set-up

Incentive spirometrv followup treatment

or if patient is charged a flat fee per day, amount of

that per day charge ●

1 7 . Who delivers each of the following types of therapeutic interventions?

a.

b.

c*

d.

18. In

IPPB

Incentive spirometry

Ultrasonic nebulizer administration of a drug

Simple aerosol generator

administration of a drug

what medical/surgical specialty is your medical director

trained (e.g., pulmonary medicine, anesthesiology, thoracic

surgery, etc.)?

19. How many total employees are there in your department?

a. How many are registered therapists?

b. How many are certified technicians?

c . How many are registry eligible graduates?

d. How many are students?

e. How many are on-the-job trained?

f. How many are other? (Please specify.)
.—

2 0 . How many

a. Full

b. Part

21. How many

a. IPPB

of your employees

time

time

of the f 01 lowing

machine

are

pieces of equipment do you own?

b. Ultrasonic nebulizers

c. Volume-cycled ventilators

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