194 ORIEL (Mortality Risk Prediction in Emergency Laparotomy): A Comparison of Mortality Risk Prediction Tools

Abstract

Abstract Aim Emergency laparotomies carry significant risk of morbidity and mortality. Risk calculation tools are essential to identify high-risk patients and inform clinicians in decision making. As part of a multi-centre research initiative, a retrospective study of all emergency laparotomies in a major trauma centre was conducted to determine the most accurate predictor of thirty-day mortality by comparing four, internationally recognised, risk assessment tools. Method Patients who underwent emergency laparotomy were identified using hospital databases. National Emergency Laparotomy Audit (NELA) was used to record pre- and post-operative mortality scores. The Portsmouth Physiological and Operative Severity Score for the enumeration of Mortality and Morbidity (P-POSSUM); American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) and Surgical Outcome Risk Tool (SORT) were used to calculate risk of mortality for each patient. The Receiver Operating Curve (ROC) statistical method was chosen to compare the results of each in order to establish the tool most pertinent to prediction of local mortality. Results 274 patients underwent emergency laparotomies at the Trust between December 2017 to December 2019. Of these, 96.7% (n=265) survived the 30-day post -operative period and 3.3% (n= 9) died. The ROC comparator demonstrated 100% sensitivity for the calculation of NELA, P-POSSUM and ACS-NSQIP and specificity of 77%, 76% and 63% for NELA, ACS-NSQIP and P-POSSUM respectively. SORT was found to be the poorest indicator of post-operative mortality. Conclusions NELA is the most accurate predictor of 30-day mortality in patients who undergo emergency laparotomy. Comparison with the outcomes of other centres will help confirm our results.