**AHRQ Patient Safety Indicators:**

**Initial Software Release -- Version 2.1**

**March 13, 2003**

**Summary of Changes From Published Reference "Measures of Patient
Safety Based on Hospital Administrative Data -- The Patient Safety
Indicators**[^1]**" to the Software Release**

The following changes were implemented in version 2.1 of the Patient
Safety Indicator (PSI) software code and reflect changes based on
updates to ICD-9-CM codes as well as refinements of the indicator
definitions in response to research utilizing the beta version. The
ICD-9-CM code updates incorporate changes from Fiscal Year (FY) 2003
(effective 10-1-2002). There were no changes from FY 2002 (effective
10-1-2001) that impacted the PSI definitions. Version 2.1 is the first
public release of the PSI software.

Changes listed below summarize differences between the publication of
the technical report and the actual codes in the PSI software, version
2.1.

+-------+------------+-------------+-----------------------------------+
| **    | **         | ***C        | ***Change***                      |
| *Indi | *Indicator | omponent*** |                                   |
| cator | Name       |             |                                   |
| Modu  | (#)***     |             |                                   |
| le*** |            |             |                                   |
+=======+============+=============+===================================+
| PSI   | Multiple   | Denominator | Removed MDC 15 exclusions for the |
|       | Indicators | (exclusion, | following indicators because DRGs |
|       |            | population) | for most neonates are not         |
|       |            |             | included in the population at     |
|       |            |             | risk, making the exclusion        |
|       |            |             | redundant: Postoperative          |
|       |            |             | hemorrhage and hematoma,          |
|       |            |             | Postoperative metabolic and       |
|       |            |             | physiologic derangement,          |
|       |            |             | Accidental puncture and           |
|       |            |             | laceration, Postoperative         |
|       |            |             | respiratory failure,              |
|       |            |             | Postoperative PE and DVT,         |
|       |            |             | Postoperative sepsis,             |
|       |            |             | Postoperative wound dehiscence.   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Immuno-     | Added code 52.82 "Pancreatic      |
|       | Indicators | compromised | homotransplant" to the definition |
|       |            | State       | of Immunocompromised state used   |
|       |            |             | as an exclusion in several        |
|       |            |             | indicators. Removed all DRGs from |
|       |            |             | definition.                       |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Medical     | New DRGs from FY 2002 and 2003    |
|       | Indicators | discharges  | and the DRGs related to burns     |
|       |            |             | (inadvertently excluded in the    |
|       |            |             | earlier work) of 505, 508-511,    |
|       |            |             | and 521-524 were added to the     |
|       |            |             | definition of medical discharges  |
|       |            |             | for the applicable PSI            |
|       |            |             | denominators.                     |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Surgical    | New DRGs from FY 2002 and 2003    |
|       | Indicators | discharges  | and the DRGs related to burns     |
|       |            |             | (inadvertently excluded in the    |
|       |            |             | earlier work) of 504, 506, 507,   |
|       |            |             | 512 -- 520, and 525-527 were      |
|       |            |             | added to the definition of        |
|       |            |             | surgical discharges for the       |
|       |            |             | applicable PSI denominators.      |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Trauma      | 1.  The new codes (FY 2003)       |
|       | Indicators | exclusion   |     813.45, "Torus fracture of    |
|       |            |             |     radius," and 823.4x, "Torus   |
|       |            |             |     fracture," were added to the  |
|       |            |             |     exclusion definition of       |
|       |            |             |     trauma for the applicable     |
|       |            |             |     PSIs.                         |
|       |            |             |                                   |
|       |            |             | 2.  Modified to include DRGs for  |
|       |            |             |     trauma in pediatric patients  |
|       |            |             |     (DRGs 30, 33) and DRGs for    |
|       |            |             |     burns (DRGs 456-460,          |
|       |            |             |     504-511). In addition, DRGs   |
|       |            |             |     which do not directly         |
|       |            |             |     indicate trauma were removed  |
|       |            |             |     (DRGs 447-455).               |
|       |            |             |                                   |
|       |            |             | 3.  All e-codes were removed from |
|       |            |             |     the format definition of      |
|       |            |             |     trauma.                       |
+-------+------------+-------------+-----------------------------------+
| PSI   | Accidental | Naming      | The indicator "Technical          |
|       | Puncture   | convention  | Difficulty with Procedure" was    |
|       | or         |             | renamed "Accidental Puncture or   |
|       | Laceration |             | Laceration" to clarify the        |
|       | (PSIs 15   |             | indicator description.            |
|       | and 25)    |             |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Birth      | Denominator | A modification was made to the    |
|       | Trauma     | (exclusion, | exclusion of premature infants    |
|       | (PSI 17)   | premature)  | with cerebral hemorrhage based on |
|       |            |             | new codes for gestational age (FY |
|       |            |             | 2003). The new codes 765.21 "\<24 |
|       |            |             | completed weeks of gestation"     |
|       |            |             | through 765.27 "33-34 completed   |
|       |            |             | weeks of gestation" were added to |
|       |            |             | the exclusion for this indicator. |
|       |            |             | These are in addition to the      |
|       |            |             | existing exclusion for birth      |
|       |            |             | weight under 2500 grams (codes    |
|       |            |             | 765.01-765.08, 765.11-765.18).    |
+-------+------------+-------------+-----------------------------------+
| PSI   | Death in   | Denominator | Added code V10.53 "Renal pelvis"  |
|       | Low        | (exclusion, | to the exclusion definition of    |
|       | Mortality  | cancer)     | cancer.                           |
|       | DRGs (PSI  |             |                                   |
|       | 2)         |             |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Death in   | Denominator | DRGs for neonatal discharges      |
|       | Low        | (exclusion, | (386-391) were removed from the   |
|       | Mortality  | population) | denominator, since these are by   |
|       | DRGs (PSI  |             | definition zero mortality. As a   |
|       | 2)         |             | result, the neonatal subindicator |
|       |            |             | was removed.                      |
+-------+------------+-------------+-----------------------------------+
| PSI   | Decubitus  | Denominator | MDC 14 (obstetrics) was excluded  |
|       | ulcer (PSI | (exclusion, | from the population at risk.      |
|       | 3)         | population) |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | 1.  For all subindicators a       |
|       | Rescue     | (exclusion  |     principal diagnosis exclusion |
|       | (PSI 4)    | population) |     was added for the inclusion   |
|       |            |             |     population to ensure only     |
|       |            |             |     patients with only qualifying |
|       |            |             |     secondary codes are included  |
|       |            |             |     (e.g. FTR -- pneumonia,       |
|       |            |             |     exclude principal dx of       |
|       |            |             |     pneumonia).                   |
|       |            |             |                                   |
|       |            |             | 2.  To incorporate                |
|       |            |             |     recommendations from the      |
|       |            |             |     clinical review panel,        |
|       |            |             |     patients age 75 and older     |
|       |            |             |     were excluded from the        |
|       |            |             |     population at risk.           |
|       |            |             |                                   |
|       |            |             | 3.  Modified to exclude MDC 15,   |
|       |            |             |     neonates, from the            |
|       |            |             |     denominator definition, since |
|       |            |             |     complications in this         |
|       |            |             |     population may be clinically  |
|       |            |             |     distinct from other           |
|       |            |             |     populations and are coded in  |
|       |            |             |     a different manner.           |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | Codes for complication in         |
|       | Rescue     | (inclusion, | obstetric patients were added to  |
|       | (PSI 4)    | acute renal | the denominator inclusion renal   |
|       |            | failure)    | failure definition including      |
|       |            |             | "Acute renal failure following    |
|       |            |             | labor and delivery" (669.3x) and  |
|       |            |             | "Complications following abortion |
|       |            |             | and ectopic and molar             |
|       |            |             | pregnancies, renal failure"       |
|       |            |             | (639.3).                          |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | 1.  A principal diagnosis         |
|       | Rescue     | (exclusion, |     exclusion for acute renal     |
|       | (PSI 4)    | acute renal |     failure after abortion was    |
|       |            | failure)    |     added (codes 634.3x, 635.3x,  |
|       |            |             |     636.3x, 637.3x, and 638.3x).  |
|       |            |             |                                   |
|       |            |             | 2.  The codes defining trauma     |
|       |            |             |     were added to this exclusion. |
|       |            |             |                                   |
|       |            |             | 3.  The codes for GI hemorrhage   |
|       |            |             |     were added to this exclusion. |
|       |            |             |                                   |
|       |            |             | 4.  Definition of shock used as   |
|       |            |             |     an exclusion with Acute Renal |
|       |            |             |     Failure was modified to       |
|       |            |             |     include additional types of   |
|       |            |             |     shock (ICD-9-CM codes: 995.0, |
|       |            |             |     995.4, 998.0, 669.1x, 999.4,  |
|       |            |             |     785.5, 634.5x, 635.5x,        |
|       |            |             |     636.5x, 637.5x, 638.5,        |
|       |            |             |     639.5).                       |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | The denominator exclusion was     |
|       | Rescue     | (exclusion, | expanded by adding the codes      |
|       | (PSI 4)    | DVT/PE)     | 415.11 "Iatrogenic pulmonary      |
|       |            |             | embolism and infarction," 415.19  |
|       |            |             | "Other pulmonary embolism and     |
|       |            |             | infarction," 673.2x, "Obstetrical |
|       |            |             | pulmonary embolism" and codes     |
|       |            |             | indicating thromboemobolism       |
|       |            |             | following abortion (634.6x,       |
|       |            |             | 635.6x, 636.6x, 637.6x, 638.6 and |
|       |            |             | 639.6).                           |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | The new codes (FY 2003), 995.91   |
|       | Rescue     | (inclusion, | "Systemic inflammatory response   |
|       | (PSI 4)    | sepsis)     | syndrome due to infectious        |
|       |            |             | process without organ             |
|       |            |             | dysfunction" and 995.92 "Systemic |
|       |            |             | inflammatory response syndrome    |
|       |            |             | due to infection process with     |
|       |            |             | organ dysfunction" were added to  |
|       |            |             | the denominator-inclusion         |
|       |            |             | definition of sepsis.             |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | Definition of infection used in   |
|       | Rescue     | (exclusion, | the sepsis exclusion criteria was |
|       | (PSI 4)    | sepsis)     | modified to include DRGs for      |
|       |            |             | infection in pediatric patients   |
|       |            |             | (DRGs 70, 81, 91, 279, 322, 417)  |
|       |            |             | and additional DRGs for bacterial |
|       |            |             | infections (DRGs 415 and 423).    |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | 1.  The code for complication in  |
|       | Rescue     | (inclusion, |     obstetric patients was added  |
|       | (PSI 4)    | shock)      |     to the denominator inclusion  |
|       |            |             |     shock definition              |
|       |            |             |     "Complications following      |
|       |            |             |     abortion and ectopic and      |
|       |            |             |     molar pregnancies, shock      |
|       |            |             |     "(639.5).                     |
|       |            |             |                                   |
|       |            |             | 2.  Also added the codes for      |
|       |            |             |     "Shock, unspecified, without  |
|       |            |             |     mention of trauma" (785.50)   |
|       |            |             |     and "Shock, cardiogenic"      |
|       |            |             |     (785.51 ).                    |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | 1.  A principal diagnosis         |
|       | Rescue     | (exclusion, |     exclusion for shock after     |
|       | (PSI 4)    | shock)      |     abortion was added (634.5x,   |
|       |            |             |     635.5x, 636.5x, 637.5x,       |
|       |            |             |     638.5, 639.5).                |
|       |            |             |                                   |
|       |            |             | 2.  Expanded to include the GI    |
|       |            |             |     hemorrhage codes in the       |
|       |            |             |     exclusion for Shock.          |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | 1.  The new codes (FY 2003)       |
|       | Rescue     | (inclusion, |     537.84 "Dieulafoy lesion      |
|       | (PSI 4)    | gastr       |     (hemorrhagic) of stomach and  |
|       |            | ointestinal |     duodenum" and 569.86          |
|       |            | hemorrhage) |     "Dieulafoy lesion             |
|       |            |             |     (hemorrhagic) of intestine"   |
|       |            |             |     were added to the             |
|       |            |             |     denominator-inclusion         |
|       |            |             |     definition of                 |
|       |            |             |     gastrointestinal hemorrhage.  |
|       |            |             |                                   |
|       |            |             | 2.  In addition to the new codes  |
|       |            |             |     above, the code 456.20        |
|       |            |             |     "Bleeding esophageal varices  |
|       |            |             |     in diseases classified        |
|       |            |             |     elsewhere, with bleeding" was |
|       |            |             |     added to this                 |
|       |            |             |     denominator-inclusion         |
|       |            |             |     definition.                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Failure to | Denominator | This exclusion criteria was       |
|       | Rescue     | (exclusion, | modified to exclude a specific    |
|       | (PSI 4)    | gastr       | diagnosis of alcoholism (see list |
|       |            | ointestinal | of codes below) and the exclusion |
|       |            | hemorrhage) | for drug dependency was removed.  |
|       |            |             |                                   |
|       |            |             | Alcoholism codes:                 |
|       |            |             |                                   |
|       |            |             | 291.0 - Alcohol withdrawal        |
|       |            |             | delirium; 291.1 - Alcohol         |
|       |            |             | amnestic syndrome; 291.2 - Other  |
|       |            |             | alcoholic dementia; 291.3 -       |
|       |            |             | Alcohol withdrawal hallucinosis;  |
|       |            |             | 291.4 - Idiosyncratic alcohol     |
|       |            |             | intoxication; 291.5 - Alcoholic   |
|       |            |             | jealousy; 291.81 - Other          |
|       |            |             | specified alcoholic psychoses,    |
|       |            |             | alcohol withdrawal; 291.89 -      |
|       |            |             | Other specified alcoholic         |
|       |            |             | psychoses, other; 291.9 -         |
|       |            |             | Unspecified alcoholic psychosis;  |
|       |            |             | 303.0x - Acute alcohol            |
|       |            |             | intoxication; 303.9x - Other and  |
|       |            |             | unspecified alcohol dependence;   |
|       |            |             | 305.0x - Nondependent abuse of    |
|       |            |             | drugs, alcohol abuse; 425.5 -     |
|       |            |             | Alcoholic cardiomyopathy; 571.0 - |
|       |            |             | Alcoholic fatty liver; 571.1 -    |
|       |            |             | Acute alcoholic hepatitis;        |
|       |            |             | 571.2 - Alcoholic cirrhosis of    |
|       |            |             | liver; 571.3 - Alcoholic liver    |
|       |            |             | damage, unspecified; 535.3x -     |
|       |            |             | Alcoholic gastritis; 980.0 -      |
|       |            |             | Toxic effect of alcohol, ethyl    |
|       |            |             | alcohol; 980.9 - Toxic effect of  |
|       |            |             | alcohol, unspecified alcohol      |
+-------+------------+-------------+-----------------------------------+
| PSI   | Iatrogenic | Denominator | MDC 14 (obstetrics) was excluded  |
|       | Pn         | (exclusion, | from the population at risk.      |
|       | eumothorax | population) |                                   |
|       | (PSI 6)    |             |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Iatrogenic | Denominator | The new code (FY 2002) 81.34      |
|       | Pn         | (exclusion, | "Refusion of dorsal and           |
|       | eumothorax | thoracic    | dorsolumbar spine, anterior       |
|       | (PSI 6)    | surgery)    | technique" was added to the       |
|       |            |             | denominator-exclusion definition  |
|       |            |             | of thoracic surgery.              |
+-------+------------+-------------+-----------------------------------+
| PSI   | Pos        | Denominator | MDC 14 (obstetrics) was excluded  |
|       | toperative | (exclusion, | from the population at risk.      |
|       | hip        | population) |                                   |
|       | fracture   |             |                                   |
|       | (PSI 8)    |             |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Pos        | Denominator | Based on new coding guidelines    |
|       | toperative | (exclusion, | (FY 2003), the code 997.02        |
|       | hip        | stroke)     | "Postoperative cerebrovascular    |
|       | fracture   |             | accident" was added to the        |
|       | (PSI 8)    |             | denominator-exclusion definition  |
|       |            |             | of stroke.                        |
+-------+------------+-------------+-----------------------------------+
| PSI   | Pos        | Denominator | The new codes (FY 2003) 537.84    |
|       | toperative | (exclusion, | "Dieulafoy lesion (hemorrhagic)   |
|       | P          | gastr       | of stomach and duodenum" and      |
|       | hysiologic | ointestinal | 569.86, "Dieulafoy lesion         |
|       | and        | hemorrhage) | (hemorrhagic) of intestine" were  |
|       | Metabolic  |             | added to the                      |
|       | D          |             | denominator-exclusion definition  |
|       | erangement |             | of gastrointestinal hemorrhage.   |
|       | (PSI 10)   |             |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Pos        | Denominator | Definition of shock was modified  |
|       | toperative | (exclusion, | to include additional types of    |
|       | P          | shock)      | shock (ICD-9-CM codes: 995.0,     |
|       | hysiologic |             | 995.4, 998.0, 669.1x, 999.4,      |
|       | and        |             | 785.5, 634.5x, 635.5x, 636.5x,    |
|       | Metabolic  |             | 637.5x, 638.5, 639.5).            |
|       | D          |             |                                   |
|       | erangement |             |                                   |
|       | (PSI 10)   |             |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Pos        | Denominator | Definition of infection was       |
|       | toperative | (exclusion, | modified to include DRGs for      |
|       | Sepsis     | infection)  | infection in pediatric patients   |
|       | (PSI 13)   |             | (DRGs 70, 81, 91, 279, 322, 417)  |
|       |            |             | and additional DRGs for bacterial |
|       |            |             | infections (DRGs 415 and 423).    |
+-------+------------+-------------+-----------------------------------+
| PSI   | Pos        | Numerator   | The new codes (FY 2003) 995.91    |
|       | toperative | (sepsis)    | "Systemic inflammatory response   |
|       | Sepsis     |             | syndrome due to infectious        |
|       | (PSI 13)   |             | process without organ             |
|       |            |             | dysfunction" and 995.92 "Systemic |
|       |            |             | inflammatory response syndrome    |
|       |            |             | due to infection process with     |
|       |            |             | organ dysfunction" were added to  |
|       |            |             | the numerator definition of       |
|       |            |             | sepsis.                           |
+-------+------------+-------------+-----------------------------------+
| PSI   | Selected   | Naming      | The indicator "Infection Due to   |
|       | Infections | convention  | Medical Care" was renamed         |
|       | Due to     |             | "Selected Infections Due to       |
|       | Medical    |             | Medical Care" to clarify the      |
|       | Care (PSIs |             | indicator description.            |
|       | 7 and 23)  |             |                                   |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Comorbidity | The new codes (FY 2003),          |
|       | Indicators | Index,      | 428.20-3, "Systolic heart         |
|       | (Risk      | Congestive  | failure," 428.30-3, "Diastolic    |
|       | a          | Heart       | heart failure," and 428.40-3,     |
|       | djustment) | Failure     | "Combined systolic and diastolic  |
|       |            |             | heart failure" were added to the  |
|       |            |             | comorbidity index definition of   |
|       |            |             | congestive heart failure.         |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Comorbidity | 1.  The new codes (FY 2003),      |
|       | Indicators | Index,      |     445.01 and 445.02             |
|       |            | Peripheral  |     "atheroembolism involving the |
|       | (Risk      | Vascular    |     extremities," 445.81,         |
|       | a          | Disease     |     "atheroembolism of the renal  |
|       | djustment) |             |     artery," and 445.89           |
|       |            |             |     "atheroembolism of other      |
|       |            |             |     sites" were added to the      |
|       |            |             |     comorbidity definition of     |
|       |            |             |     peripheral vascular disease.  |
|       |            |             |                                   |
|       |            |             | 2.  DRGs 108, 100, 111, 478 and   |
|       |            |             |     479 were excluded from this   |
|       |            |             |     comorbidity definition, in    |
|       |            |             |     order to remove all of the    |
|       |            |             |     cases that were admitted with |
|       |            |             |     a cardiac principal diagnosis |
|       |            |             |     and underwent arterial        |
|       |            |             |     surgery..                     |
|       |            |             |                                   |
|       |            |             | 3.  Codes describing arterial     |
|       |            |             |     dissection (441.00-3) were    |
|       |            |             |     removed from this comorbidity |
|       |            |             |     definition, since these codes |
|       |            |             |     often do not reflect a        |
|       |            |             |     chronic disease.              |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Risk-       | Modified to incorporate new DRGs  |
|       | Indicators | Adjustment, | from FY 2003:                     |
|       | (Risk      | DRGs        |                                   |
|       | a          |             | 1.  DRGs 512-518, 524-527 were    |
|       | djustment) |             |     individually added to the DRG |
|       |            |             |     risk adjustment model.        |
|       |            |             |                                   |
|       |            |             | 2.  DRGs 519 and 520 were         |
|       |            |             |     aggregated and added to the   |
|       |            |             |     DRG risk adjustment model.    |
|       |            |             |                                   |
|       |            |             | 3.  DRGs 521, 522, and 523 were   |
|       |            |             |     aggregated and added to the   |
|       |            |             |     DRG risk adjustment model.    |
+-------+------------+-------------+-----------------------------------+
| PSI   | Multiple   | Risk-       | Identified five DRGs that were no |
|       | Indicators | Adjustment, | longer valid as of 10/1/01 (112,  |
|       | (Risk      | DRGs        | 434-437) however they were        |
|       | a          |             | retained for backward             |
|       | djustment) |             | compatibility.                    |
+-------+------------+-------------+-----------------------------------+
| PSI   | Software   | Parameter   | All parameter files were renamed  |
|       | reference  | files       | to reflect the module to which    |
|       | files      |             | they belong.                      |
+-------+------------+-------------+-----------------------------------+

[^1]: McDonald K, Romano P, Geppert J, et al. Measures of Patient Safety
    Based on Hospital Administrative DataCThe Patient Safety Indicators.
    Technical Review 5 (Prepared by the University of California San
    Francisco*B*Stanford Evidence-based Practice Center under Contract
    No. 290-97-0013). AHRQ Publication No. 02-0038 . Rockville, MD:
    Agency for Healthcare Research and Quality. August 2002. ISBN
    1-58763-121-0