Influence of gender on postoperative pain in percutaneous nephrolithotomy: A prospective observational study

Abstract

Background and Aims: Percutaneous nephrolithotomy (PCNL) is the procedure of choice for managing large renal calculi. Although minimally invasive, it is associated with pain due to dilatation of renal capsule, parenchymal tract, and nephrostomy tube placement. Gender differences in pain perception and analgesic requirement have not been studied in PCNL surgeries. This study was done to evaluate the influence of gender on pain. Material and Methods: It was a prospective observational study including 60 ASA physical status I and II patients. The number of males and females were 29 and 31, respectively. Analgesic requirement and postoperative pain score were assessed by visual and dynamic visual analog scales (VAS, DVAS) score fourth hourly for first 24 h. Rescue analgesia was IV paracetamol 1 g when pain score exceeded four. VAS scores were assessed using Mann-Whitney test. Rescue analgesia was calculated as frequency and proportions. A P value of <0.05 was considered statistically significant. Results: The mean pain score values (VAS P = 0.361; DVAS P = 0.332) and postoperative fentanyl (P = 0.703) did not show a statistically significant difference in males and females. The requirement of rescue paracetamol was higher in females with 30 out of 31 females demanding a rescue analgesic in comparison to 15 out of 29 male patients (P = 0.001). Conclusion: No significant difference was observed in postoperative pain among males and females in patients undergoing PCNL surgery. The analgesic requirement, however, was found to be more in females than in males.