A comparative study of hyperbaric bupivacaine (0.5%) with hyperbaric levobupivacaine for spinal anesthesia in cesarean section: A randomized, controlled trial

Background: Spinal anesthesia is often used for both elective and emergency cesarean section. One earlier study has shown that intrathecal levobupivacaine given in L 3-4 space did not provide satisfactory intraoperative analgesia in all parturients. We assume that the same dose may work if given in L 2-3 intrathecal space, especially in our population with shorter stature. Materials and Methods: After Institutional Ethical Committee approval, 100 parturients (American Society of Anesthesiologists I-II, aged 18-40 years) and after obtaining written informed consent to received spinal anesthesia for cesarean section were randomized into four groups: Group I (0.5% hyperbaric bupivacaine 7.5 mg in L 2-3 intrathecal space), Group II (0.5% hyperbaric levobupivacaine 7.5 mg in L 2-3 intrathecal space), Group III (0.5% hyperbaric bupivacaine 10 mg in L 3-4 intrathecal space), and Group IV (0.5% hyperbaric levobupivacaine 10 mg in L 3-4 intrathecal space), respectively. Hypotension (systolic blood pressure 20% from baseline) was treated with injection mephentermine 3 mg intravenous (iv) increment (s). For the ethical reason, inadequate analgesia was treated with 0.5 mg/kg iv ketamine. Statistical analysis was performed using the SPSS version 20 software windows. A P Results: Time to onset of sensory block was faster in 0.5% hyperbaric levobupivacaine 10 mg given in L 3-4 intrathecal space (Group IV P = 0.013). No significant difference was found in time to reach maximum block level (T 4 -T 6 ). Median peak sensory block level was significantly lower in Group II as compared with other group T 6 versus T 4 ; F = 106.159; P 2-3 intrathecal space ( P = 0.028). The degree of motor block or motor block regression was similar in all the groups. Intraoperative rescue analgesia was required in 20% of patients in Group II (levobupivacaine 7.5 mg in L 2-3 ); it was 4% in each of the remaining groups ( P = 0.082). Injection mephentermine used was 24%, 32%, 48%, and 28%, respectively, in Group I to IV though it did not reach statically significance. Conclusion: Levobupivacaine 7.5 mg can be used in lower segment cesarean section when given in L 2-3 space. Onset is faster, and hemodynamic stability is more with levobupivacaine. At the higher dose, the duration of action bupivacaine seems to be longer.