Intraoperative ketamine reduces immediate postoperative opioid consumption after spinal fusion surgery in chronic pain patients with opioid dependency: a randomized, blinded trial.

Perioperative handling of surgical patients with opioid dependency represents an important clinical problem. Animal studies suggest that ketamine attenuates central sensitization and hyperalgesia and thereby reduces postoperative opioid tolerance. We hypothesized that intraoperative ketamine would reduce immediate postoperative opioid consumption compared with placebo in chronic pain patients with opioid dependency undergoing lumbar spinal fusion surgery. Primary outcome was morphine consumption 0 to 24 hours postoperatively. Secondary outcomes were acute pain at rest and during mobilization 2 to 24 hours postoperatively (visual analogue scale), adverse events, and persistent pain 6 months postoperatively. One hundred fifty patients were randomly assigned to intraoperative S-ketamine bolus 0.5 mg/kg and infusion 0.25 mg·kg·h or placebo. Postoperatively, patients received their usual opioids, paracetamol and IV patient-controlled analgesia with morphine. In the final analyses, 147 patients were included. Patient-controlled analgesia IV morphine consumption 0 to 24 hours postoperatively was significantly reduced in the ketamine group compared with the placebo group: 79 (47) vs 121 (53) mg IV, mean difference 42 mg (95% confidence interval -59 to -25), P < 0.001. Sedation was significantly reduced in the ketamine group 6 and 24 hours postoperatively. There were no significant differences regarding acute pain, nausea, vomiting, hallucinations, or nightmares. Back pain at 6 months postoperatively compared with preoperative pain was significantly more improved in the ketamine group compared with the placebo group, P = 0.005. In conclusion, intraoperative ketamine significantly reduced morphine consumption 0 to 24 hours after lumbar fusion surgery in opioid-dependent patients. The trend regarding less persistent pain 6 months postoperatively needs further investigation.

Preoperative dexamethasone reduces acute but not sustained pain after lumbar disk surgery: a randomized, blinded, placebo-controlled trial.

Glucocorticoids have attracted increasing attention as adjuvants in the treatment of acute postoperative pain. Furthermore, anecdotal reports may support glucocorticoids for preventing sustained postoperative pain. We explored preoperative dexamethasone combined with paracetamol and ibuprofen on acute and sustained pain after lumbar disk surgery. In this blinded study, 160 patients undergoing lumbar disk surgery were randomly assigned to 16 mg IV dexamethasone or placebo. All patients received perioperative paracetamol and ibuprofen, and postoperative IV patient-controlled analgesia with morphine. Primary outcome was pain during mobilization (visual analog scale) 2 to 24 hours postoperatively. Secondary outcomes were acute pain at rest, morphine consumption, nausea, vomiting, ondansetron consumption, sedation, and quality of sleep. Patients were followed up by written questionnaire 3 months postoperatively. Acute pain during mobilization (weighted average area under the curve, 2-24 hours) was significantly reduced in the dexamethasone group: 33 (22) mm vs placebo 43 (18) mm, (95% confidence interval [CI] 3-16) P = 0.005. Vomiting 0 to 24 hours postoperatively was reduced in the dexamethasone group (17 episodes) vs placebo (51 episodes) P = 0.036. No other differences were observed. However, 6.5% (95% CI 2-15) in the dexamethasone group vs placebo 0% had an antibiotically treated wound infection (P = 0.13). Sixteen percent (95% CI 7-26) vs 8% (95% CI 0-17) reported new weakness/paralysis of the legs in the dexamethasone and placebo groups, respectively, 3 months postoperatively (P = 0.20). In conclusion, preoperative dexamethasone significantly reduced pain during mobilization and vomiting, after lumbar disk surgery. No significant effects were observed 3 months postoperatively.

One-week postoperative patency of lower extremity in situ bypass graft comparing epidural and general anesthesia: retrospective study of 822 patients.

BACKGROUND: The purpose of this study was to determine whether anesthesia affects graft patency after lower extremity arterial in situ bypass surgery. METHODS: This investigation was a retrospective study using a national database on vascular surgical patients at a single medical institution. We assessed a total of 822 patients exposed to infrainguinal in situ bypass vascular surgery over the period of January 2000 to September 2010. RESULTS: All patients included in the study (age [mean ± SD] 70.8 ± 9.7 years) underwent infrainguinal in situ bypass (n = 885) for lower extremity revascularization under epidural (n = 386) or general (n = 499) anesthesia. Thirty-day mortality (3.4% for epidural anesthesia versus 4.4% general anesthesia; P = 0.414) and comorbidity were comparable in the 2 groups. Graft occlusion within 7 days after surgery was reported in 93 patients, with a similar incidence in the epidural (10.1%) and general (10.8%) anesthesia groups (P = 0.730). When examining a subgroup of patients (n = 242) exposed to surgery on smaller vessels (femorodistal in situ bypass procedures, n = 253), the incidence of graft occlusion was also similar in the 2 groups at 14.0% and 9.4%, respectively (P = 0.262). CONCLUSION: This retrospective study has shown that when graft patency is evaluated 7 days after surgery, anesthetic choice (epidural or general anesthesia) does not influence outcome.