Comparison of fractionated versus bolus dose of bupivacaine heavy (0.5%) in spinal anesthesia for elective caesarean section—A prospective, randomized, single blind, and clinical trial

Context: Spinal anesthesia using bolus dose of bupivacaine has rapid onset of action but it may precipitate hypotension, whereas fractionated dose will provide hemodynamic stability as well as prolong the duration of analgesia. Aims: We aimed to compare the hemodynamic stability as our primary objective and block characteristics and duration of effective analgesia as our secondary objectives. Methods: The study was carried out in eighty patients with ASA I or II undergoing elective lower segment caesarean section (LSCS) under spinal anesthesia after institutional ethical clearance. Patients were divided into two groups. Group B patients received spinal anesthesia with single bolus dose of bupivacaine heavy (0.5%) and Group F patients received fractionated dose with two-third of the total dose of bupivacaine heavy (0.5%) given initially followed by one-third dose after 90 seconds. Statistical Analysis Used: Time of onset and regression of sensory and motor blockage, intraoperative hemodynamics, and duration of analgesia were recorded and analyzed using student's t test. Results: Six patients in group F developed hypotension as compared to 16 patients in group B which were statistically significant (p < 0.05). There was statistically highly significant difference in duration of effective analgesia. It was longer for group F (338.25 ± 19.824 minutes), in comparison with group B (266.875 ± 19.861 minutes). Duration of sensory and motor block were also longer in group F as compared to group B (p < 0.0001). Conclusions: Fractionated dose of spinal anesthesia provides greater stability in terms of hemodynamic parameters and prolonged duration of analgesia as compared to bolus dose.