Pneumoperitoneum in the presence of acute and chronic kidney injury: An experimental model in rats

Purpose There is evidence that pneumoperitoneum induces transient changes in renal function in healthy individuals. Its effect on malfunctioning kidneys is not well known. We investigated effects caused by pneumoperitoneum in animals with impaired renal function. Materials and Methods Male Wistar rats underwent subtotal (5/6) nephrectomy in 2 sequential steps to induce renal failure. Two and 10 weeks postoperatively rats were classified with acute and chronic kidney injury, respectively. At those time points all rats were exposed to 0, 5 and 8 mm Hg pneumoperitoneum for 60 minutes. Changes in creatinine, blood urea nitrogen and creatinine clearance were measured. Histopathological changes and apoptosis were also evaluated in the subgroups. Results A total of 18 rats with acute and 18 with chronic kidney injury completed the study. Creatinine and blood urea nitrogen did not change after applying pneumoperitoneum in the different pressure subgroups but creatinine clearance significantly decreased in the 5 and 8 mm Hg subgroups in rats with acute and chronic kidney injury. Histopathological findings in the acute kidney injury subgroups that underwent 5 and 8 mm Hg pressure revealed ischemic changes while compensatory hypertrophy was noticed in the chronic injury pressurized subgroups. The apoptotic count was significantly higher in the chronic injury subgroups compared to their acute injury pressurized counterparts. Conclusions Pneumoperitoneum seems feasible in rats with impaired baseline renal function. Particularly chronic cases should not be considered a contraindication to pneumoperitoneum while in acute cases pneumoperitoneum might be detrimental.