Effects of Pneumoperitoneum on Renal Concentrating Ability

Abstract

Background: Electrolytes concentration and body fluid volume were regulated mainly under the control of renal system. Defect in renal perfusion may lead to alteration in renal function which will lead to imbalance in body fluid and electrolyte. The pneumoperitoneum induced by abdominal laparoscopic procedure may caused defects in renal perfusion and this will lead to impairment of renal concentrating ability.Objective: This work is aimed to assess the renal concentration ability among patients undergoing abdominal laparoscopic surgical operations.Patients and Methods: This study was conducted on 70 patients who were undergoing abdominal laparoscopic surgical operations at Al-Hilla Teaching Hospital and 70 healthy subjects as volunteers, the period of study were from November 2015 to August 2016. Full history and physical examination was performed on all the study subjects. The history involved any past history of ischemic heart diseases, renal disease or those who presented with impaired renal function and diabetes mellitus in pre-operative examination were excluded from the study. The following parameters were done for all patients and controls: plasma creatinine (Pcr), plasma sodium (PNa), plasma osmolarity (Posm), urine creatinine (Ucr), urine sodium (UNa) and urine osmolarity (Uosm). The values of urine and plasma of different parameters were used for calculation of the osmolar clearance (Cosm), fractional excretion of sodium (FENa), free water clearance (CH2O) and creatinine clearance (Ccr). Results: The mean values of Pcr for patients enrolled in this study were significantly higher after operation than that before operations (P ˂ 0.001). While there was a significant decrease in the means of UNa, Uosm, Cosm, Ccr and PNa after operation in comparison with the preoperative values (for all P ˂ 0.001). On the other hand, there were no significant changes in the mean of Posm and FENa after operation in comparison with the preoperative values. Also, this study revealed significant changes in CH2O; there were 62:70 (88.6 %) of patients had negative CH2O, and 8:70 (11.4 %) who had positive CH2O in pre-operative collected samples. However, after operation 52:70 (74.3 %) of patients who had positive CH2O, and only 18:70 (25.7%) had negative CH2O, (P<0.05).Conclusions: In this study, we found that the abdominal laparoscopic operations had an effect on concentrating ability of the kidneys. The osmolar clearance and free water clearance were simple and inexpensive tests for measurement of renal concentrating ability.