Internal comparative audit in a thoracic surgery unit using the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM)
A. Brunelli et al., Internal comparative audit in a thoracic surgery unit using the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM), EUR J CAR-T, 19(6), 2001, pp. 924-928
Objective: The aim of the study was to use the physiological and operative
severity score for the enumeration of mortality and morbidity (POSSUM) to a
ssess the performance of our thoracic surgery unit during two successive pe
riods of activity. Methods: From 1992 through 1997, 801 candidates for thor
acic procedures at our institution were considered fur the study. After val
idation of the logistic regression model, including the POSSUM score, obser
ved and POSSUM-predicted morbidities were compared within two groups Of pat
ients divided by year of operation (group 1: 1992-1994, n = 362; group 2: 1
995-1997, n = 439) by means of the z-test for the comparison of a proportio
n with an expected value. Results: The POSSUM-predicted morbidity was signi
ficantly lower than the observed one in the first period of activity of our
unit (19.6 vs. 24.3%, respectively; z-test for the comparison of a proport
ion with an expected value, 2.25: P = 0.01), whereas no difference was foun
d in the second period (20.5 vs. 19.1%, respectively: z-test for the compar
ison of a proportion with an expected value, -0.71; P = 0.76). Conclusions:
The result suggests a worse-than-expected performance of our unit in the f
irst period of activity, showing that POSSUM can be reliably applied as an
instrument of internal comparative audit in a thoracic surgery unit. (C) 20
01 Elsevier Science B.V. All rights reserved.