Post-laparoscopy pain reduction project (POLYPREP III): Intraperitoneal normal saline instillation versus intraperitoneal Ringer's lactate

Although laparoscopic surgery generally results in less postoperative pain compared to open laparotomy, many patients still experience post-laparoscopy pain in the shoulder, upper abdomen, and lower abdomen, as well as discomfort at port-site incisions and drain sites. This study aimed to compare the effects of intraperitoneal normal saline instillation versus intraperitoneal Ringer's lactate instillation on postoperative pain following benign gynecological laparoscopic procedures. This single-center, prospective, single-blind (participant), randomized controlled trial employed a parallel design and was conducted at the University Malaya Medical Centre, Kuala Lumpur, Malaysia. This study included 80 women who underwent benign laparoscopic gynecological surgeries and were assigned to two intervention groups: Group A received intraperitoneal normal saline instillation, while Group B received intraperitoneal Ringer's lactate instillation. The intensity of post-laparoscopic pain in the shoulder, upper abdominal, and lower abdominal area at 24-, 48-, and 72-h was measured using a standard numerical rating scale. There was no difference in the severity of shoulder and lower abdominal pain at 24, 48, and 72 h post-surgery, both at rest and during movement. However, there was a significant difference in the severity of postoperative upper abdominal pain at 24 and 48 h (95 % confidence interval: 0.66–1.94,P = 0.015; 0.021–0.68,P = 0.034; respectively). Intraperitoneal Ringer's lactate infusion does not provide superior pain relief for the shoulder, upper abdomen, and lower abdomen compared to intraperitoneal normal saline instillation. However, there is a significant improvement in the severity of post-laparoscopic upper abdominal pain following intraperitoneal normal saline instillation at 15 mL/kg.