Utility of the NELA score and other variables in predicting the need for ICU admission post emergency laparotomy

Abstract

The preoperative risk score and key recommendations designed by the National Emergency Laparotomy Audit (NELA) have resulted in improved outcomes for patients undergoing emergency laparotomy. However, the recommended routine intensive care/high dependency unit (ICU) admission for high-risk patients is not always logistically possible and predictive models are needed to identify patients who will benefit. We conducted a study of patients undergoing emergency laparotomy at our tertiary hospital in Western Australia between 2018 and 2023 to identify factors that were associated with the need for ICU admission after emergency laparotomy, as defined by the requirement for a vasopressor infusion, continuous renal replacement therapy or ventilation. Of 1100 patients identified, 875 were included in the primary analysis. In multivariate analysis, the only independent predictive factors of the need for ICU therapies were the American Society of Anesthesiologists grade (P=0.017) and peak intraoperative serum lactate concentration >2 mmol/L (P=0.038). An increased NELA score was associated with mortality; however, it was not associated with the requirement for any ICU therapy (P=0.993). Although only 35.8% of high-risk patients were admitted to ICU, there was no apparent increase in adverse outcomes including mortality or unexpected ICU admission, and 27.4% of patients that were admitted to ICU received no specific therapies. This study provides a basis for the development of new predictive models for ICU admission post emergency laparotomy, and suggests the possibility that routine elective admission might not necessarily add value beyond that achieved by other NELA standards.