Abstract
BACKGROUND: Laparoscopic abdominal surgery has been widely used to reduce the length of hospital stay and complications from open abdominal surgery. During the operation, the creation of pneumoperitoneum is used for better visualization of the operating field. However, the effect of pneumoperitoneum on kidney function is unknown. We aimed to identify risk factors and predictors associated with AKI development following laparoscopic abdominal surgery. METHODS: A single-center prospective cohort study of laparoscopic abdominal surgery patients between June 2012 and December 2013. Acute kidney injury (AKI) was identified by Kidney Disease Improving Global Outcome (KDIGO) criteria. Urinary neutrophil gelatinase associated lipocalin (uNGAL) was measured on the first 3 days after surgery as a surrogate marker of AKI. RESULTS: Of the 64 patients, 23 (35%) developed postoperative AKI. The mean age, initial blood pressure, and initial glomerular filtration rate were not different between AKI and non-AKI groups. Inflation time and exposure index were significantly higher in the AKI group compared to non-AKI group (192.0 vs 151.1 min, p = 0.045, and 2325.9 vs 1866.1 mmHg-minutes, p = 0.035). Operation time, mean intra-abdominal pressure, duration of intraoperative hypotension, amount of blood loss and intravenous fluid were not different between groups. In multivariable analysis adjusted for age, diabetes, baseline estimated glomerular filtration rate, and type of operation (urological surgery), exposure index was significantly associated with postoperative AKI, with odds ratio (95% CI) 1.47 (1.05-2.04), p = 0.024. By combining the intraoperative parameters with clinical model the area under the receiver operating characteristic curve was 0.71 (95% CI 0.58-0.84). CONCLUSIONS: AKI was a common condition in laparoscopic abdominal surgery. Exposure index has been proposed as a novel predictor of laparoscopic abdominal surgery associated AKI.