Evaluation of outcome of laparoscopic colorectal resection with POSSUM, Portsmouth POSSUM and colorectal POSSUM

Background: This study evaluated the Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM), Portsmouth (P) POSSUM and colorectal (CR) POSSUM in laparoscopic colorectal resection.

Methods: Observed mortality and morbidity rates in 400 patients who underwent laparoscopic colorectal resection were compared with those predicted by POSSUM, P-POSSUM and CR-POSSUM.

Results: Observed mortality and morbidity rates were 0.5 and 19.0 per cent respectively. Mortality rates predicted by POSSUM, P-POSSUM and CR-POSSUM were 10.8, 4.0 and 5.6 per cent respectively, and the morbidity rate predicted by POSSUM was 43.0 per cent. The predicted and observed mortality and morbidity rates showed significant lack of fit. The conversion rate to open surgery was 11.5 per cent. The mortality rate for patients having conversion was 2 per cent and was not significantly different to that predicted by P-POSSUM (4 per cent; P = 0.493) or CR-POSSUM (5 per cent; P = 0.370). In this group, the observed and POSSUM-predicted morbidity rates were also similar (43 versus 48 per cent respectively; P = 0.104).

Conclusion: POSSUM, P-POSSUM and CR-POSSUM overestimated mortality and morbidity in patients who underwent laparoscopic colorectal resection. However, the mortality rate in patients who required conversion fitted the models of P-POSSUM and CR-POSSUM, and the morbidity rate was comparable to that predicted by POSSUM.