An observational study comparing the clinical effects of standard pressure and low pressure pneumoperitoneum in patients undergoing laparoscopic cholecystectomy

The laparoscopic surgical technique is increasingly used for performing a variety of intraabdominal surgeries routinely as it is minimally invasive, surgeries like cholecystectomy, appendectomy, colectomy and hysterectomy among others . It involves gas insufflation into the peritoneal cavity producing pneumoperitoneum which increases intra-abdominal pressure (IAP) to 12-14 mm of Hg (standard pneumoperitoneum). Laparoscopy can also be done with lower IAP of 8-10 mmHg (low pressure pneumoperitoneum).

As pneumoperitoneum produces significant changes ,we attempt to compare the hemodynamic changes in patient undergoing laparoscopic cholecystectomy using different intra-abdominal pressures created by carbon dioxide insufflation. The increase in intra-abdominal pressures by carbon dioxide  insufflation into the peritoneal cavity at a standard pressure and prolonged exposure to such pressures can produce changes in the cardiovascular and pulmonary efficiency. Although these changes may be tolerated by healthy individuals with adequate cardiopulmonary reserve, individuals with existing cardiopulmonary ailments, especially in elderly and hemodynamically compromised patients, may not tolerate these changes.

Increased IAP due to pneumoperitoneum has a biphasic effect on venous return. Due to redistribution of pooled blood from the splanchnic circulation, there is an initial increase in the circulating blood volume, causing increase in the venous return and flow. Further increase in the IAP leads to inferior vena caval compression and decreases venous return with pronounced reduction in cardiac output . However, An emerging trend has been the use of lower IAP which has shown better patient hemodynamics  and lesser postoperative pain ; use of low-pressure pneumoperitoneum in the range of 8-10 mm Hg in an attempt to lower intra-abdominal pressure that could reduce the impact of pneumoperitoneum on the hemodynamic circulation of intra-abdominal organs as well as cardiopulmonary function as lower pressures are claimed to be safe and effective in decreasing cardiopulmonary complications and pain . While providing adequate working space. Still, the confirmation continues to be weak , and the argument remains unresolved.

Hence we hypothesize low pressure pneumoperitoneum as a safer alternative to the use of standard pressure of pneumoperitoneum during laparoscopic surgeries. The aim of the research is to evaluate the clinical effects elicited by pneumoperitoneum of different pressures (low IAP versus standard IAP) during laparoscopic cholecystectomy.