The median effective dose of preemptive gabapentin on postoperative morphine consumption after posterior lumbar spinal fusion.

BACKGROUND: A single dose of preemptive gabapentin reduces postoperative pain and postoperative analgesic consumption. However, the optimal dose of preemptive gabapentin remains to be evaluated. METHODS: In this prospective study, we defined the median effective analgesic dose using an up-and-down sequential allocation technique of preemptive gabapentin in 67 patients undergoing elective posterior lumbar spinal fusion. The efficacy of the study drug was assessed by morphine consumption during the first 24 h postoperatively. RESULTS: The median effective analgesic dose (median value and 95% confidence interval) of gabapentin was 21.7 mg/kg (19.9-23.5 mg/kg). CONCLUSION: Given the large dose of gabapentin needed, further powered studies are warranted to assess side effects.

Lack of a pre-emptive effect of low-dose ketamine on postoperative pain following oral surgery.

PURPOSE: The aim of this study was to assess the effect of pre- vs postincisional low-dose iv ketamine on postoperative pain in outpatients scheduled for oral surgery under general anesthesia. METHODS: Eighty-four patients were randomly assigned to receive intravenously saline before and after surgery in Group 1, ketamine 300 microg x kg(-1) iv before and saline after surgery in Group 2, saline before and ketamine 300 microg x kg(-1) iv after surgery in Group 3. Postoperative analgesia consisted of iv proparacetamol and ketoprofen. Rescue analgesia consisted of nalbuphine 200 microg x kg(-1) iv. Analgesia at home consisted of oral ketoprofen, and acetaminophen with codeine as rescue analgesia. A telephone interview was conducted on the first and second postoperative days. RESULTS: There were no significant differences between groups with respect to pain scores, the number of patients requiring nalbuphine in the postanesthesia care unit (PACU), (36.7%, 38.7%, and 39.5% for Groups 1, 2, and 3 respectively), or nalbuphine consumption in the PACU (66.5 microg x kg(-1) +/- 16.8, 75.9 microg x kg(-1) +/- 17.5, 66.7 microg x kg(-1) +/- 21.6 for Groups 1, 2, and 3 respectively). The number of rescue analgesic tablets taken at home, and time to first request for rescue analgesia, sedation scores, or side-effects were similar amongst groups. No patient required nalbuphine in the ambulatory care unit. CONCLUSIONS: There was no benefit to pre-emptive administration of ketamine 300 microg x kg(-1) iv whether administered pre- or postoperatively.

Clinical efficacy of the brachial plexus block via the posterior approach.

BACKGROUND AND OBJECTIVES: The posterior approach to the brachial plexus remains underused. We assessed the clinical effectiveness of this technique for shoulder surgery. METHODS: One hundred eighty-seven consecutive patients scheduled to undergo shoulder surgery were assessed after a single-injection nerve-stimulation technique using ropivacaine 0.75%. Sensory and motor block was evaluated in the distribution area of each terminal branch of the brachial plexus every 10 minutes for 30 minutes. Postoperative analgesia was evaluated at regular time intervals at rest and with passive movement, up to 24 hours postoperatively. RESULTS: The brachial plexus was reached at a depth of 6.5 +/- 0.9 cm. One attempt was sufficient in 85% of patients. Neck pain during insertion of the needle was encountered in 6 (3%; 95% confidence interval [CI], 0.7%-5.6%) patients. Thirty minutes after ropivacaine injection, the axillary, radial, median, musculocutaneous, and ulnar nerves were anesthetized in 100%, 100%, 97%, 96%, and 68% of cases, respectively. The success rate of the block was 98%. Postoperative analgesia was satisfactory in 97% of patients up to 12 hours after the initial injection. Dysphonia and Horner's syndrome were observed in 14 (7%; 95% CI, 3.7%-11.2%) and 12 (6%; 95% CI, 2.9%-9.9%) patients, respectively. One patient (0.5%; 95% CI, 0%-1.5%) had documented hemidiaphragmatic paresis. No complication was noted during the 3-month follow-up period. CONCLUSIONS: This study reports the clinical effectiveness of the single-injection nerve-stimulation technique for the brachial plexus block via the posterior approach in patients undergoing shoulder surgery. It appears to be effective, relatively safe, and well tolerated.