Clinical trials

The evolution of minimally invasive gynecology has transitioned from traditional laparotomy to laparoscopy, and most recently, to vNOTES (Vaginal Natural Orifice Transluminal Endoscopic Surgery). By combining the visual advantages of endoscopy with the scarless approach of vaginal surgery, vNOTES has demonstrated superior outcomes in terms of reduced postoperative pain, shorter hospital stays, and improved cosmetic results compared to traditional total laparoscopic hysterectomy (TLH). Despite these advancements, post-laparoscopic pain syndrome (PLPS) remains a significant clinical challenge. Characterized by deep-seated abdominal pressure and referred shoulder-tip pain, PLPS is primarily attributed to the irritation of the phrenic nerve caused by residual carbon dioxide and the formation of carbonic acid on the peritoneal surface. In the Trendelenburg position required for gynecologic procedures, this gas often becomes trapped in the subdiaphragmatic space, leading to significant distress that can delay discharge even when the surgical site itself is healing well. The physiological impact of the pneumoperitoneum is largely pressure-dependent. The landmark study by Barczyński and Herman (2004) in general surgery established that maintaining a low-pressure pneumoperitoneum (\<10 mmHg) significantly reduces peritoneal stretching and the subsequent inflammatory response. Furthermore, the technique of intraperitoneal saline washout has been proposed to physically remove residual CO2 and dilute acidic metabolites, thereby mitigating phrenic nerve irritation. While these techniques have been validated in abdominal laparoscopic procedures such as cholecystectomy, their efficacy within the unique framework of vNOTES hysterectomy remains unexplored. vNOTES naturally utilizes lower pressures than traditional laparoscopy, yet the incidence of referred pain persists. There is currently a lack of high-level evidence determining whether the addition of a standardized saline washout provides an incremental benefit over low-pressure vNOTES alone. The aim of this prospective, randomized controlled trial is to evaluate the impact of intraperitoneal saline washout on postoperative pain scores and analgesic consumption in patients undergoing low-pressure vNOTES hysterectomy. The investigators hypothesize that the combination of low-pressure insufflation and active saline washout will result in a synergistic reduction in post-laparoscopic pain, facilitating an ultra-fast-track recovery protocol.

vNOTES, initially employed for cholecystectomy, appendectomy, and nephrectomy, made its debut in the field of gynecologic surgery in 2012. The advantages of vNOTES-such as minimized postoperative discomfort, quicker recovery, and superior cosmetic results-combined with gynecologists' familiarity with the vaginal approach, have contributed to the swift global adoption of vNOTES in gynecological procedures. Preliminary trials have demonstrated its safety and practicality. Although laparoscopy plays a crucial role in surgical procedures, post-operative pain remains a major concern linked to this minimally invasive technique, despite being less intense than the pain from a laparotomy. Visceral pain after laparoscopy can stem from the stretching of the peritoneum and diaphragm caused by pneumoperitoneum, as well as from inflammatory cytokines released due to blood accumulation in the abdominal cavity. This pain is typically described as a dull, widespread ache found in the abdominal or thoracic region and often extends to the shoulders. It corresponds to a rise in painkiller use aligned with Enhanced Recovery After Surgery strategies for both preoperative and postoperative stages. Moreover, the Trendelenburg position could intensify shoulder pain due to increased diaphragm irritation from pneumoperitoneum. Effective pain management promotes early movement, lowering the risk of blood clots and decreasing lung complications like atelectasis or pneumonia. Additionally, postoperative pain negatively impacts the quality of life immediately after surgery. To lessen both the occurrence and intensity of post-surgical pain, numerous experts advocate for the use of multimodal therapy in surgical patients. The aim of this study was to evaluate the efficacy of combined low-pressure CO2 pneumoperitoneum and intraperitoneal infusion of normal saline for reducing the incidence and severity of postoperative pain.