Abstract
BACKGROUND: Emergency laparotomy is performed for a wide range of life-threatening conditions and is associated with significant morbidity and mortality. Risk prediction models facilitate accurate communication of operative risk with patients and relatives, in addition to benchmarking unit outcomes. Greater understanding of the impact of sarcopenia or myosteatosis will encourage the adoption of routine radiological reporting of body composition and the incorporation of skeletal muscle gauge (SMG) into risk prediction models. This study investigated the prognostic significance of SMG, an aggregate assessment of sarcopenia or myosteatosis, in patients who had undergone an emergency non-trauma-related laparotomy. METHODS: This was a retrospective cohort study of patients aged ≥ 18 years who underwent an emergency laparotomy at the Queen Elizabeth Hospital between January 2014 and December 2020. Body composition and patient outcomes were analysed. RESULTS: In all, 1090 patients with a mean(standard deviation) age of 62.3(17.5) years underwent emergency laparotomy (bowel obstruction, 52.7%; perforation, 26.3%; ischaemia, 9.5%). Overall 30- and 90-day mortality was 10.0% and 11.6%, respectively. On multivariate analysis, low SMG was associated with worse 30- and 90-day mortality, with odds ratios of 2.12 (95% confidence interval (c.i.) 1.18 to 3.83; P = 0.012) and 2.64 (95% c.i. 1.55 to 4.48; P < 0.001), respectively. Low SMG was also associated with an increased length of hospital stay (odds ratio 1.45; 95% c.i. 1.22 to 1.72; P < 0.001). CONCLUSION: A low SMG was associated with increased postoperative mortality and length of hospital stay after emergency laparotomy. Patients undergoing computed tomography imaging for acute abdominal pain should undergo routine reporting of body composition.