Effect of gradual increase in intra-abdominal pressure on bradycardia during creation of pneumoperitoneum in laparoscopic abdominal surgery: A Prospective Randomised study

Laparoscopic surgery because of its minimal invasive nature, is now a preferred technique for a range of surgical procedures including cholecystectomy, appendectomy, hernioplasty, various gynaecological surgeries and advanced surgeries like colorectal, pancreatic, urological surgeries and endocrine surgery like adrenalectomy etc. It involves the creation of pneumoperitoneum through the insufflation of carbon dioxide (COâ‚‚) into the abdominal cavity to provide space for surgical manipulation. One of the well-known physiological responses to pneumoperitoneum is increased intra-abdominal pressure (IAP) and vagal stimulation causing bradycardia, a slow heart rate (<60 bpm) that can be clinically significant when it drops below 40 beats per minute or sometimes asystole causing significant hemodynamic instability and may require pharmacological intervention, such as the administration of atropine. And these bradycardia event occur mostly at the time of creation of pneumoperitoneum. The incidence of laparoscopy-induced bradycardias has been reported to range widely between 3.4 and 28% of cases. The current standard practice for pneumoperitoneum creation typically involves rapid insufflation of COâ‚‚ to achieve the desired intra-abdominal pressure (IAP) of 12-14 mmHg rapidly. However, this rapid inflation may exacerbate the incidence of bradycardia by abruptly increasing intra-abdominal pressure, thus affecting cardiovascular function. While gradual insufflation, where pressure is increased in small, incremental steps to increase IAP gradually may provide a more controlled response, potentially reducing the vagal response and the incidence of bradycardia. Despite these theoretical concepts, evidence supporting the superiority of gradual insufflation over rapid insufflation in reducing bradycardia during laparoscopic abdominal surgery is sparse and inconclusive. This study aims to fill this gap by investigating whether a gradual increase in IAP during pneumoperitoneum creation can reduce the incidence and severity of bradycardia compared to the conventional rapid insufflation technique. Specifically, this study will assess whether a gradual increase in intra-abdominal pressure (IAP) reduces the incidence of bradycardia (defined as a heart rate of less than 60 beats per minute or a reduction of more than 20% from baseline) when compared to the conventional rapid inflation technique. Given the high prevalence of bradycardia in laparoscopic abdominal surgeries, particularly with the rapid inflation method, the findings from this research may contribute to optimizing anesthetic and surgical protocols, improving patient safety, reducing perioperative cardiovascular complications and better overall patient outcomes.