Comparison of two concentrations of isobaric intrathecal levobupivacaine for vaginal hysterectomy

This study was performed to compare the anesthetic efficacy and safety of two concentrations of local anesthetic agent levobupivacaine in patients undergoing vaginal hysterectomy. Forty-four patients of ASA I and II, were randomized to receive an intrathecal injection of one of two local anesthetic solutions. Each patient in Group A (n = 22) received 2 ml of isobaric levobupivacaine 5 mg/ml (10 mg) with 25 μg of fentanyl, while each patient in Group B (n = 22) received 4 ml of isobaric levobupivacaune 2.5 mg/ml (10 mg) with 25 μg of fentanyl. The onset and duration of sensory block at dermatome level T10, maximum upper spread of sensory block, time for two segment regression of sensory block as well as the onset, intensity and duration of motor block were recorded, as were any adverse effects, such as bradycardia, hypotension, nausea, and/or vomiting, etc. The onset of sensory block was similar in both the groups. The onset of motor block was significantly faster in group A compared with that in group B. The duration of sensory and motor blockade was of shorter duration in group B (P < 0.05). However, patients in group A required more use of a vasoactive drug (phenylephrine) compared with group B