Prediction of Outcome After Emergency High-Risk Intra-abdominal Surgery Using the Surgical Apgar Score

BACKGROUND: With current literature quoting mortality rates up to 45%, emergency high-risk abdominal surgery has, compared with elective surgery, a significantly greater risk of death and major complications. The Surgical Apgar Score (SAS) is predictive of outcome in elective surgery, but has never been validated exclusively in an emergency setting. METHODS: A consecutive prospective single-center cohort study of 355 adults undergoing emergency high-risk abdominal surgery between June 2013 and May 2014 is presented. The primary outcome measure was 30-day mortality. Secondary outcome measures were postoperative major complications, defined according to the Clavien-Dindo scale as well as the American College of Surgeons' National Surgical Quality Improvement Program guidelines, and intensive care unit admission. The SAS was calculated postoperatively. Cochran-Armitage test for trend was used to evaluate the incidence of both outcomes. Area under the curve was used to demonstrate the scores' discriminatory power. RESULTS: One hundred eighty-one (51.0%) patients developed minor or no complications. The overall incidence of major complications was 32.7% and the overall death rate was 16.3%. Risk of major complications, death, and intensive care unit admission increased significantly with decreasing SAS (P < .001). The score's c-statistics were 0.63. CONCLUSIONS: We have demonstrated the SAS to be significantly predictive but weakly discriminative for major complications and death among adults undergoing emergency high-risk abdominal surgery. Despite its predictive value, the SAS cannot in its current version be recommended as a standalone prognostic tool in an emergency setting.