Introduction: Perforation peritonitis is one of the most common surgical emergencies in the world and is associated with a high incidence of AKI. We hypothesized that renal artery ultrasound parameters will be able to detect AKI as per AKIN Criteria. This study is aimed to evaluate the efficacy of RRI and semiquantitative PDU done preoperatively and 24 hours post operatively 1) in prediction of AKI at day 3, 2) persistent AKI at hospital discharge, need for renal replacement therapy, length of ICU stay, length of hospital stay, days on ventilator and days on vasopressors.
Methods: 148 ASA I/II patients, age 18-65 years planned for surgery due to perforation peritonitis were enrolled in the study. Patients with AKI or CKD on admission and poor abdominal echogenicity were excluded from the trial. RRI and PDU was done preoperatively and 24 hours post operatively. AUROC of renal doppler ultrasound was assessed for prediction of AKI.
Results: AUC of preoperative RRI/PDU, 24 hours postoperative RRI and postoperative RRI/PDU is (0.904; 95% CI: 0.845 to 0.946), (0.916; 95% CI: 0.859 to 0.955) and (0.915; 95% CI: 0.858 to 0.954), respectively. Among all the parameters, 24 hours postoperatively RRI was the best predictor of AKI at cut off point of >0.6 with AUC of 0.916 for predicting acute kidney injury.
Conclusions: RRI/PDU ratio and PDU score done 24 hours post operatively carries highest diagnostic accuracy for diagnosing AKI. Doppler parameters can predict secondary outcomes like mortality, length of ICU stay, days of ventilator support.
