Background: Physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) scoring is a validated scoring system in the audit of surgical outcomes; however, evaluation of this system has mostly been applied to open surgical techniques. The present study examines the validity of POSSUM in predicting morbidity and mortality in patients undergoing laparoscopic cholecystectomy (LC) with the recognized risk factor for postoperative mortality of advanced age.
Methods: All patients aged 80 years or over undergoing LC in one surgical unit between January 1993 and December 1999 were identified from the surgical operations database of the hospital. Case-note review was used to collate data in terms of clinical and operative factors as described in POSSUM. Observed/POSSUM estimated (O/E) ratio of morbidity and 30-day mortality were calculated.
Results: Laparoscopic cholecystectomy was performed in 76 patients aged 80 years or over during the study period. Of these patients, case notes for 70 patients (92%) were available for review. Median (range) age was 83 years (80-93 years) and median (range) American Society of Anesthesiologists score was 2 (2-4). Twenty-six (34%) of 70 patients underwent cholecystectomy during an acute admission. The mean physiology severity score was 23 and operative severity score, 8. A significant postoperative morbidity was observed in 15 (22%) of 70 patients. There was no 30-day mortality. Using exponential analysis, POSSUM predicted morbidity in 15 patients and mortality in seven patients. Thus, O/E ratios for morbidity and mortality were 1 and 0, respectively.
Conclusion: POSSUM scoring performs well in predicting morbidity, but overpredicts mortality, after LC in patients aged over 80 years. An assessment of its application to other laparoscopic procedures merits evaluation.