Intraoperative infusion of S(+)-ketamine enhances post-thoracotomy pain control compared with perioperative parecoxib when used in conjunction with thoracic paravertebral ropivacaine infusion.

OBJECTIVE: The authors explored the use of continuous postoperative subpleural paravertebral ropivacaine alone combined with intraoperative S(+)-ketamine or perioperative parecoxib as a new approach to pain control after major thoracotomy. DESIGN: A randomized study. SETTINGS: A single university hospital. PARTICIPANTS: Eighty patients underwent elective thoracotomy under general anesthesia. METHODS: Study patients were assigned to 1 of 3 groups: group K (n = 27) received intraoperative S(+)-ketamine (0.5 mg/kg as a preincisional bolus followed by a continuous infusion 400 µg/kg/h), group P (n = 27) received perioperative parexocib (40 mg before extubation and 12 hours postoperatively), and group C (n = 26) served as the control group. At the end of surgery, all patients received a subpleural paravertebal infusion of ropivacaine. MEASUREMENTS AND MAIN RESULTS: Pain was assessed by visual analog scores and supplemental morphine consumption with PCA up to 48 hours postoperatively. The duration of stay and postoperative functional parameters also were collected. Compared with ropivacaine alone, S(+)-ketamine significantly reduced pain scores at rest and during movement at 4, 12, 24, and 48 hours postoperatively. Moreover, at 24 and 48 hours, pain was less after S(+)-ketamine compared with parexocib. S(+)-ketamine also reduced morphine needs in comparison to placebo at 4, 12, 24, and 48 hours and in comparison to parexocib at 48 hours after thoracotomy. There were no differences in parameters for lung or bowel function, mobilization time, or ICU and hospital stay. CONCLUSIONS: In patients with thoracotomy, postoperative paravertebral ropivacaine combined with intraoperative S(+)-ketamine provided better early postoperative pain relief than ropivacaine and perioperative parexocib or ropivacaine alone.

Improvement of pain treatment after major abdominal surgery by intravenous S+-ketamine.

UNLABELLED: The use of intraoperative racemic ketamine for pain prevention after abdominal surgery is controversial. We compared one preincisional i.v. injection of S(+)-ketamine with its preincisional and repeated intraoperative use in 45 patients undergoing surgery with epidural and general anesthesia. S(+)-ketamine is a new drug formulation that contains the more potent S(+)-stereoisomer of ketamine. Patients were randomized to receive placebo, 0.5 mg/kg preincisional S(+)ketamine, or 0.5 mg/kg preincisional and 0.2 mg/kg intraoperative S(+)-ketamine repeated at 20-min intervals. In the postoperative period, epidural ropivacaine (2 mg/mL; 0.12 mL.kg(-1).h(-1)) was infused for pain therapy. Patients who received repeated S(+)-ketamine reported smaller pain scores than those who received placebo after awakening and 3 and 6 h later (P < or = 0.05). Fewer patients with repeated S(+)-ketamine required additional analgesics than those with placebo (P < or = 0.05). Cumulative consumption of additional diclofenac and dextropropoxyphene at 24 h was less after single (P < 0.05) and repeated (P < 0.05) S(+)-ketamine versus placebo. After awakening, patients who received repeated S(+)-ketamine reported being in a better mood than those in the other groups (P < 0.05). No psychotomimetic side effects were noted. In conclusion, preincisional and repeated intraoperative small-dose S(+)-ketamine added to general and epidural anesthesia causes better postoperative pain relief than general and epidural anesthesia alone. IMPLICATIONS: After major visceral surgery, preincisional and repeated intraoperative small-dose S(+)-ketamine added to general and epidural anesthesia causes better postoperative pain relief than general and epidural anesthesia alone.