Spinal Anesthesia; Lower Segment Cesarean Section Comparison of Atients With Hyperbaric Bupivacaine Versus Isobaric Bupivacaine as Used for Spinal Anesthesia

Abstract

ABSTRACT… Objective: The purpose of the study is to compare and assess the sensory and motor block along with the associated hemodynamic changes that occur in the patient population operated for a lower segment cesarean section (LSCS), when they are given 0.5% hyperbaric bupivacaine versus 0.5% isobaric bupivacaine as used for spinal anesthesia. Study Design: Prospective double blind randomized trial. Period: 6 months duration from April 2014 to September 2014. Setting: A tertiary care hospital in the city of Karachi, Pakistan. Method: The study population consisted of 60 patients belonging to the ASA 1 and ASA 2 category, who underwent a lower segment cesarean section, and comparative analysis of the efficacy and associated hemodynamic changes of hyperbaric with isobaric bupivacaine. The patient population was segmented into two groups both groups containing 30 patients, group A receiving hyperbaric bupivacaine 0.5% as 2.5ml ( 12.5mg dose ) and the second group designated as, group B receiving isobaric bupivacaine 0.5% as 2.5ml ( 12.5mg dose) intrathecally. The resultant sensory and motor blockade was determined using pin prick and bromage scale respectively. Results: There was a significant difference found among the two groups under study, when compared at 3min interval regarding the sensory blockade. The level of T6 block was reached in 33.33% (n=10) patients belonging to group A and 56.66% (n= 17) patients in group B. It was observed that there was no significant change among the two groups at 5min interval regarding sensory and motor blockade respectively. The immediate sensory blockade with isobaric bupivacaine in group B produced greater decrease in the systolic and mean arterial blood pressure when contrasted with hyperbaric bupivacaine in group A at 5min interval, but after time interval of 45min there was no statistically significant change observed. Conclusions: According to our study the effects of isobaric bupivacaine were more significantly predictable; hence have a higher efficacy, when contrasted against hyperbaric bupivacaine in lower section cesarean section spinal anesthesia. Quick sensory blockade with isobaric bupivacaine was associated with more decrease in blood pressures when contrasted with the hyperbaric bupivacaine, but this result is not statistically significant. Key words:Lower segment cesarean section, Spinal anesthesia, hyperbaric bupivacaine, isobaric bupivacaine.