159 Factors associated with low mortality after emergency laparotomy

Abstract Introduction The NELA study produced reports which describe hospital-level performance for process measures and mortality after emergency laparotomy. These reports have not described which factors are common amongst low mortality hospitals. This study used aggregated NELA datasets to identify process measures associated with low mortality hospitals. Methods The RAG database from the Eighth NELA report was downloaded. Hospitals were split into low mortality (lowest 25% of hospitals) and high mortality. For each process measure, hospitals were split into 'Green' (>80%) and 'Not Green'. Hospitals were classified into low- or high-volume centres (highest quartile for volume). Mortality rate was compared to each process measure using chi-squared tests. Results There were 21710 cases. National NELA-adjusted mortality was 9.1% (range, 2.5-18.4%). Hospitals with mortality lower than 6.7% were in the lowest quartile. Hospitals which performed more than 170 cases (range, 16-401) were 'high-volume' hospitals. There was variation in achieving a 'Green' rating in all the process measures but none were common amongst low mortality hospitals. The only common factor amongst low mortality hospitals was a significantly lower proportion of patients who had an unplanned return to theatre (0-5% vs >5%, P=0.009). Conclusions None of the process measures which NELA have identified, and ask hospitals to enter data for, have any impact on improving mortality after emergency laparotomy. The only factor common to low-mortality hospitals was a low rate of unplanned return to theatre, which suggests that the key element to do correctly is perform the primary surgery safely and to a high standard.