Evaluating frailty may complement APACHE II in estimating mortality in elderly patients admitted to the ICU after digestive surgery

Abstract

ObjectiveTo analyze whether frailty can improve the prediction of mortality in patients admitted to the ICU after digestive surgery. DesignProspective, observational, 6-month follow-up study of a cohort of patients admitted to the ICU between June 1, 2018, and June 1, 2019. SettingSurgical ICU of a third level hospital. PatientsSeries of successive patients older than 70 years who were admitted to the ICU immediately after a surgical intervention on the digestive system. 92 patients were included and 2 were excluded due to loss of follow-up at 6 months. InterventionsUpon admission to the ICU, severity and prognosis were assessed by APACHE II, and fragility by the Clinical Frailty Scale and the modified Frailty Index. Main variables of interestICU, in-hospital and 6-month mortality. ResultsThe model that best predicts mortality in the ICU is the APACHE II, with an area under the ROC curve (AUC) of 0.89 and a good calibration. The model that combines APACHE II and Clinical Frailty Scale is the one that best predicts in-hospital mortality (AUC: 0.82), significantly improving the prediction of isolated APACHE II (AUC: 0.78; Integrated Discrimination Index: 0.04). Frailty is a predictor of mortality at 6 months, being the model that combines Clinical Frailty Scale and Frailty Index the one that has shown the greatest discrimination (AUC: 0.84). ConclusionsFrailty can complement APACHE II by improving its prediction of hospital mortality. Furthermore, it offers a good prediction of mortality 6 months after surgery. For mortality in ICU, frailty loses its predictive power, whereas isolated APACHE II shows excellent predictive capacity.