Mean Duration Of Sensory Block Research Articles

Comparison of ropivacaine 0.5% (in glucose 5%) with bupivacaine 0.5% (in glucose 8%) for spinal anaesthesia for elective surgery

Hyperbaric solutions of ropivacaine have been used successfully to provide spinal anaesthesia. This study was designed to compare the clinical efficacy of hyperbaric ropivacaine with that of the commercially available hyperbaric preparation of bupivacaine. Forty ASA grade I-II patients undergoing lower-abdominal, perineal or lower-limb surgery under spinal anaesthesia were recruited and randomized to receive ropivacaine 5 mg ml(-1) (with glucose 50 mg ml(-1)), 3 ml or bupivacaine 5 mg ml(-1) (with glucose 80 mg ml(-1)), 3 ml. The level and duration of sensory block, intensity and duration of motor block, and time to mobilize and micturate were recorded. Patients were interviewed at 24 h and at 1 week to identify any residual problems. All blocks were adequate for the proposed surgery, but there were significant differences between the two groups in mean time to onset of sensory block at T10 (ropivacaine 5 min; bupivacaine 2 min; P<0.005), median maximum extent (ropivacaine T7; bupivacaine T5; P<0.005) and mean duration of sensory block at T10 (ropivacaine 56.5 min; bupivacaine 118 min; P=0.001). Patients receiving ropivacaine mobilized sooner (ropivacaine mean 253.5 min; bupivacaine 331 min; P=0.002) and passed urine sooner (ropivacaine mean 276 min; bupivacaine 340.5 min; P=0.01) than those receiving bupivacaine. More patients in the bupivacaine group required treatment for hypotension (>30% decrease in systolic pressure; P=0.001). Ropivacaine 15 mg in glucose 50 mg ml(-1) provides reliable spinal anaesthesia of shorter duration and with less hypotension than bupivacaine. The recovery profile for ropivacaine may be of interest given that more surgery is being performed in the day-case setting.

Addition of fentanyl to bupivacaine prolongs anesthesia and analgesia in axillary brachial plexus block

Background and Objectives: To evaluate the analgesic and anesthetic effects of 40 mL bupivacaine 0.25%, 40 mL bupivacaine 0.25% plus fentanyl 2.5 μg/mL, and 40 mL bupivacaine 0.125% plus fentanyl 2.5 μg/mL for axillary brachial plexus block. Methods: Sixty patients were randomly allocated to 3 groups and received axillary brachial plexus block with 40 mL bupivacaine 0.25% (group B), 40 mL bupivacaine 0.25% with fentanyl 2.5 μg/mL (group BF), or 40 mL bupivacaine 0.125% with fentanyl 2.5 μg/mL (group DBF). The onset times and the duration of sensory and motor blocks, duration of analgesia, hemodynamic parameters, and adverse events were noted. Results: The mean duration of sensory block and analgesia were longer in group BF (10.1 hours and 20.9 hours) than group B (6.9 hours and 11.6 hours) and DBF (5.9 hours and 12.0 hours) ( P < .01, P < .001, respectively). The mean duration of motor block was also longer in group BF (10.7 hours) than group B (4.9 hours) ( P < .01). Only 2 patients experienced motor block in group DBF. The frequency of successful block was 35% in group DBF ( P < .01). Hemodynamic parameters were similar in all groups. In group B, only 1 patient experienced dizziness. Nausea was observed in 1 patient in each fentanyl group. Conclusion: The addition of 100 μg/mL fentanyl to 0.25% bupivacaine almost doubles the duration of analgesia following axillary brachial plexus block when compared with 0.25% bupivacaine alone. Reg Anesth Pain Med 2001;26:434-438.

The morphological effects of etidocaine HCl on the spinal cord of the sheep

Four sheep received by spinal injection one ml of 2% etidocaine HCl in 5% glucose, and three received one ml of 5% glucose. One additional sheep served as an untreated control. The animals were sacrificed at 3, 7 or 28 days after the injection, and the spinal cords were removed, fixed in formalin, and submitted to gross and microscopic examination. The mean duration of sensory block in the hind limbs of those sheep that received the local anesthetic solution was 4.5 hours, and all four animals recovered completely from the anesthesia. Gross and microscopic examination of the spinal cords and roots revealed no histopathological changes attributable to the local anesthetic solution or vehicle.