Acute kidney injury: a risk scoring system for general surgical patients

Abstract

This article describes the development of a scoring system for general surgical patients to highlight those at greater risk of developing acute kidney injury (AKI). Following a search of the literature on current practice, a list of common variables was composed. Hospital Episode Statistics (HES) data from two random hospital trusts was used. With the help of a risk analysis system (CRAB Medical module, CRAB Clinical Informatics Ltd) it was possible to examine the relationship between potential risk factors and the incidence of AKI. Using Analyse-it for Excel a binary logistic model was created, which led to the development of a logistic regression equation and consequently a scoring system. The sensitivity and specificity of the model was tested using the receiver operating characteristic (ROC) curve. There was good correlation across the whole risk spectrum with an area under ROC curve of 0.806 (95% confidence intervals 0.787–0.825). The scoring system was developed into an admission checklist for general surgical patients to highlight a patient's risk of developing AKI. In a ward setting a checklist that immediately assesses the patient and produces a rapid indication as to whether the patient is at high risk or low risk would seem to be the ideal tool.