Comparison of Onset of Sensory Block after Intrathecal use of Hyperbaric and Isobaric Bupivacaine in Non-Obstetric Patients

Abstract

Background: Spinal anesthesia is commonly used in the lower limb and lower abdominal surgeries and bupivacaine is the drug used intrathecally. Bupivacaine is available in two forms isobaric having density same as CSF and hyperbaric having greater density than CSF. Objective: This study was performed to see the difference of onset of sensory block after intrathecal use of hyperbaric versus isobaric bupivacaine in non-obstetric patients. Study Design: Randomized control trial. Settings: Study was conducted in Pakistan Institute of Medical Sciences, Islamabad Pakistan. Duration: Six months from January 2020 to June 2020. Methods: Total 60 patients undergoing lower abdominal surgeries 25 to 50 years of either gender were included. The patients were randomized either intrathecal isobaric bupivacaine for group I or hyperbaric bupivacaine for group H to compere the time for onset of sensory block. Data collection was done by the study proforma and analysis was done by using the SPSS version 26. Results: Age range of the subjects was 25 to 50 years with overall average age of 37.61 ± 5.03 years. Out of total 60 patients 15 males and 45 were females and the ratio was 1:3. An average onset time for group H was significantly shorter 2.02 ± 0.85 in group H (hyperbaric bupivacaine) versus 5.53 ± 1.14 minutes with group I (isobaric bupivacaine) (p- 0.001). Conclusion: Study concluded that the use of intrathecal hyperbaric bupivacaine has rapid onset of sensory block at the T₁₀ level compared to the Isobaric bupivacaine of sensory block.