Evaluation of Surgical Performance Using V‐possum Risk‐adjusted Mortality Rates

Abstract

Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (V-POSSUM) is a risk-adjusted scoring system for predicting 30-day mortality in patients undergoing vascular surgery. It can assess surgical performance by comparing predicted deaths with observed deaths. The aim of this analysis was to assess trends in surgical performance over time using risk-adjusted 30-day mortality as the primary outcome. Major vascular surgery procedures (n = 454) were prospectively scored for V-POSSUM between 1995 and 2006. Procedures were divided into 11 consecutive time bands. Observed and predicted deaths were compared using the logistic regression equation derived for V-POSSUM. The observed death rates decreased over time, as did the predicted number of deaths calculated from the V-POSSUM scores. The overall predicted mortality rate was 17.2% and the rate varied with the 12-month period, with a high of 23.9% and a low of 9.2%. The downward trend in the predicted rate shows that the patient risk factors have changed over time and that the risk of dying has declined by almost 50% (from 21.6 to 11.1%). There was a trend towards improved surgical performance over time, with a drop in the observed to predicted ratios of deaths. Observed and predicted deaths changed over the study periods. There was a trend towards improved performance compared with the risk-adjusted predicted mortality. V-POSSUM is a useful tool in the longitudinal assessment of performance in major vascular surgery.

Physiological and Operative Severity Score for the enumeration of Mortality and Morbidity (POSSUM) System for Outcome Prediction in Elderly Patients Undergoing Major Vascular Surgery

“…For all other models the inclusion of intraoperative data represented an enormous limitation as prognostic scores and some authors considered that it makes scores neither simple or rapid to use. (16,23) Complex tools are not necessarily associated to better discrimination for risk prediction (6) and are difficult to apply on daily practice. (14) On the other hand, POSSUM models are widely available as they can be calculated by free online calculators.…”

The impact of serum albumin and serum protein levels on POSSUM score of patients with proximal femur fractures

“…The POSSUM score had initially been developed by Copelan et al to serve as a scoring system for surgical audit [1]. Following his publication, various modifications were made to adapt it to the needs of different fields in surgery, among them vascular [2], gastrointestinal [3], urologic [4] and orthopaedic [5]. The POSSUM score was further modified to adapt it for patients with proximal femur fractures who comprise a difficult at-risk group [6][7][8], For example, Ramanathan et al [6] found that POSSUM over-predicts mortality in proximal femur fracture patients and recommended that it should be used with caution, whether as an audit tool or for preoperative triage.…”

“…These 12-variable factors, 4-grade physiologic and 6 operative-factor score were developed for the general spectrum of vascular, gastrointestinal, hepatobiliary, urological and miscellaneous surgeries. Various modifications of the original form were made to provide better prediction for different groups of patients, i.e., P-POSSUM (Portsmouth) [2], V-POSSUM (vascular) [3], and CR-POSSUM (colorectal) [4]. Mohamed et al [5] developed an orthopaedic version using a modified operation classification.…”

Endovascular Repair of Juxtarenal Aneurysms

“…It has been used to assess surgical performance by comparing predicted deaths with observed deaths. 11,12 There is, however, no consensus on the best risk prediction model for mortality following elective abdominal aortic aneurysm repair. A recent analysis of 5 risk prediction models has been undertaken by using the UK National Vascular Database.…”