Objectives: Our aim was to compare unilateral spinal anesthesia produced by 6 mg hyperbaric bupivacaine or 4 mg hyperbaric bupivacaine plus 10 µg fentanyl for day-case arthroscopic knee surgery.
Material and methods: In this study we evaluated hemodynamic effects, block levels, and recovery characteristics. After approval of Institutional Ethics Committee, ASA I-II, 42 patients were enrolled into the study. Patients were randomly allocated in two groups. Group I (n=22) 6 mg hyperbaric bupivacaine+10µg fentanyl, group II (n=22) 4 mg hyperbaric bupivacaine+10µg fentanyl. The patients were applied standard monitoring, and hemodynamic parameters were recorded. Then spinal anesthesia was performed with the patient lateral decubitis position, using a 25 G Quincke spinal needle at the L3-4 intervertebral space. Parameters below were recorded for each patient: hemodynamic, time to reach to level of T12 dermatome, maximum sensory level, motor block levels and recovery characteristics level of motor block, level of sensory block, time to reach T12 dermatome.
Results: Demographic and hemodynamic variables were not different between groups (p>0.05). Although level of sensory block, and time to reach T12 dermatome were not different (p>0.05), level of motor block, ambulation time and time to discharge were significantly longer in Group I than Group II (p<0.05). Side effects were not different between groups, except more itching in Group II.
Conclusion: Spinal anesthesia with using 4 mg hyperbaric bupivacaine+10µg fentanyl outpatients undergoing knee surgery may have superiority comparing with 6 mg hyperbaric bupivacaine+10µg fentanyl for recovery characteristics.