Comparative analysis of hypobaric versus hyperbaric bupivacaine for spinal anesthesia in day-case anorectal surgery: A prospective observational study

Abstract

Background: This study aimed to compare the efficacy, safety, and discharge times of patients undergoing day-case anorectal surgery using 5 mg hyperbaric bupivacaine versus 5 mg hypobaric bupivacaine. The evaluation was based on Fast-Track Scoring criteria, which assess the suitability of patients for day-case surgery. Methods: A prospective observational study was conducted at Ankara City Hospital, including 80 patients aged 18 to 65 years within American Society of Anesthesiologists I-II risk groups scheduled for day-case anorectal surgery. All patients received spinal anesthesia with either 5 mg of 0.5% hyperbaric bupivacaine or 5 mg of 0.5% hypobaric bupivacaine. Hemodynamic parameters, sensory and motor block durations, time to first analgesic need, urination time, and discharge time were meticulously recorded and analyzed. Statistical analyses were performed using the independent samples t test and Mann-Whitney U test, with significance set at α = 0.05. Results: The hypobaric group exhibited significantly shorter sensory and motor block durations, enabling faster surgical readiness and earlier discharge. Both groups maintained comparable hemodynamic stability and postoperative complication rates. Shorter discharge times in the hypobaric group may offer potential benefits for patient turnover and cost-effectiveness. Conclusion: For patients undergoing day-case anorectal surgery, 5 mg hypobaric bupivacaine provides faster recovery and shorter discharge time than hyperbaric bupivacaine, without compromising safety. These findings suggest that hypobaric bupivacaine may be a more suitable choice in day-case settings, contributing to improved resource utilization and patient satisfaction.