Surgical Apgar Score and prediction of morbidity in women undergoing hysterectomy for malignancy

Objective: To validate whether Surgical Apgar Score can predict post-operative morbidity in patients undergoing hysterectomies for malignancies. Methods: We conducted a retrospective cohort study of consecutive hysterectomies performed for cancer at a single academic institution between 2008 and 2010. The Surgical Apgar Score (SAS) was derived as previously reported. Peri-operative complications were as outlined by the American Board for Obstetrics and Gynecology, and then further subdivided into intra-operative and post-operative events. Univariate and multivariate logistic regressions were utilized. Results: A total of 632 patients were identified. Of our cohort, 64% underwent surgery for cancer arising in the uterus, followed by ovary at 28.6% and cervix at 4%. Median patient age was 60 years old with a mean American Society of Anesthesiologists Physical Status Classification System (ASA) score of 2.5 and a median body mass index of 29. Average Surgical Apgar Score was 7.6. As SAS decreased, the risk of peri-operative complications increased (p < 0.01). On univariate analysis SAS could predict for both intra-operative and post-operative complications. However, on multivariate analyses SAS could not independently predict for any post-operative complications (OR 1.02, CI 0.47-2.17). In a multivariable model incorporating age, ASA class, SAS < 4, disease site, bowel resection and laparotomy, only ASA class and laparotomy were able to predict for postoperative complication events. Conclusions: Low Surgical Apgar Score significantly associates with morbidity in women undergoing hysterectomy for malignancy, but is unable to predict which patients will have postoperative complications. This renders the SAS less helpful for the creation of peri-operative metrics to guide post-operative care.