Incidence, risk factors, and outcomes of acute kidney injury in patients undergoing emergency laparotomy - A prospective observational exploratory study.

BACKGROUND AND AIMS: Acute kidney injury (AKI) can occur in post-laparotomy patients, with a variable incidence. This study aimed to determine the incidence of AKI in patients undergoing emergency laparotomy under general anaesthesia, the effect of preoperative variables on the development of AKI, and the association of post-operative AKI with patient outcomes.

METHODS: This prospective exploratory study in patients undergoing emergency laparotomy was followed up for 7 days to determine the incidence of post-operative AKI. We determined the patients developing different severity of AKI based on kidney disease improving global outcome staging. Fisher's exact test or Chi-squared test was used to study the association of demographic variables, and various periopertaive variables on the development of postoperative AKI. The association of AKI with the duration of hospital stay was estimated using the Wilcoxon-Mann-Whitney U Test, and Fisher's exact test was used to study the association between AKI and mortality.

RESULTS: No patient had AKI in the pre-operative period. On day 3, 18 patients; on day 5, 28 patients; and on day 7, 24 patients developed AKI. Overall, a maximum of 33 patients (out of 100) developed AKI at any time. Our study found that the American Society of Anesthesiologists (ASA) IV and sepsis were independent risk factors for post-operative AKI. Our results also show a moderate-to-high independent association between AKI and duration of hospital stay and mortality (within 30 days).

CONCLUSION: Incidence of post-operative AKI following emergency laparotomy was 33%. Higher preoperative ASA physical status and sepsis were significantly associated with postoperative AKI development.