Analgesia and side effects of the addition of 10 or 20 mu g fentanyl to articaine in spinal anesthesia for knee arthroscopy : a randomized and observer-blinded study

Objectives Articaine, a popular and rapidly acting local anesthetic in dentistry, has been also found to be beneficial in ambulatory spinal anesthesia. Analgesia in the intraoperative and immediate postoperative period may be further improved by adding fentanyl to the local anesthetic solution for spinal anesthesia. The aim was to evaluate dose-dependency of analgesia and side effects associated with intrathecal fentanyl additive to articaine for spinal anesthesia in knee arthroscopy patients. Methods In this randomized, observer- and patient-blinded study, 90 adult patients scheduled for elective ambulatory knee arthroscopy under spinal anesthesia were randomized into three groups: plain articaine 60 mg with saline (group AF0), articaine 60 mg with fentanyl 10 A mu g (group AF10) or 20 A mu g (group AF20) in a total volume of 1.9 ml. The blinded observer tested the sensory and the motor block, and performed telephone interviews on the first and seventh postoperative days. Results The median (IQR) duration of sensory block at the dermatomal level of T10 was significantly longer in groups AF10, 69 min (56) and AF20, 69 min (45) than in group AF0, 41 min (35) (p = 0.013). Motor block duration was similar in all groups (median 120 min). Group AF20 patients experienced pruritus significantly more often than patients in the other groups (p = 0.039). No acute or late anesthetic side effects occurred, and satisfaction with the anesthetic technique was the same in all groups (97% satisfied). Conclusions Fentanyl 10 or 20 A mu g as additive to articaine for spinal anesthesia prolonged the duration of sensory block significantly and similarly. Fentanyl 20 A mu g was more often associated with pruritus than fentanyl 10 A mu g.Peer reviewe

S-ketamine in patient-controlled analgesia reduces opioid consumption in a dose-dependent manner after major lumbar fusion surgery: A randomized, double-blind, placebo-controlled clinical trial

Background Spinal fusion surgery causes severe pain. Strong opioids, commonly used as postoperative analgesics, may have unwanted side effects. S-ketamine may be an effective analgesic adjuvant in opioid patient-controlled analgesia (PCA). However, the optimal adjunct S-ketamine dose to reduce postoperative opioid consumption is still unknown.Methods We randomized 107 patients at two tertiary hospitals in a double-blinded, placebo-controlled clinical trial of adults undergoing major lumbar spinal fusion surgery. Patients were randomly allocated to four groups in order to compare the effects of three different doses of adjunct S-ketamine (0.25, 0.5, and 0.75 mg ml-1) or placebo on postoperative analgesia in oxycodone PCA. Study drugs were administered for 24 hours postoperative after which oxycodone-PCA was continued for further 48 hours. Our primary outcome was cumulative oxycodone consumption at 24 hours after surgery.Results Of the 100 patients analyzed, patients receiving 0.75 mg ml(-1) S-ketamine in oxycodone PCA needed 25% less oxycodone at 24 h postoperatively (61.2 mg) compared with patients receiving 0.5 mg ml(-1) (74.7 mg) or 0.25 mg ml(-1) (74.1 mg) S-ketamine in oxycodone or oxycodone alone (81.9 mg) (mean difference: -20.6 mg; 95% confidence interval [CI]: -41 to -0.20; P = 0.048). A beneficial effect in mean change of pain intensity at rest was seen in the group receiving 0.75 mg ml(-1) S-ketamine in oxycodone PCA compared with patients receiving lower ketamine doses or oxycodone alone (standardized effect size: 0.17, 95% CI: 0.013-0.32, P = 0.033). The occurrence of adverse events was similar among the groups.Conclusions Oxycodone PCA containing S-ketamine as an adjunct at a ratio of 1: 0.75 decreased cumulative oxycodone consumption at 24 h after major lumbar spinal fusion surgery without additional adverse effects

S-ketamine in patient-controlled analgesia reduces opioid consumption in a dose-dependent manner after major lumbar fusion surgery : A randomized, double-blind, placebo-controlled clinical trial

Background Spinal fusion surgery causes severe pain. Strong opioids, commonly used as postoperative analgesics, may have unwanted side effects. S-ketamine may be an effective analgesic adjuvant in opioid patient-controlled analgesia (PCA). However, the optimal adjunct S-ketamine dose to reduce postoperative opioid consumption is still unknown. Methods We randomized 107 patients at two tertiary hospitals in a double-blinded, placebo-controlled clinical trial of adults undergoing major lumbar spinal fusion surgery. Patients were randomly allocated to four groups in order to compare the effects of three different doses of adjunct S-ketamine (0.25, 0.5, and 0.75 mg ml-1) or placebo on postoperative analgesia in oxycodone PCA. Study drugs were administered for 24 hours postoperative after which oxycodone-PCA was continued for further 48 hours. Our primary outcome was cumulative oxycodone consumption at 24 hours after surgery. Results Of the 100 patients analyzed, patients receiving 0.75 mg ml(-1) S-ketamine in oxycodone PCA needed 25% less oxycodone at 24 h postoperatively (61.2 mg) compared with patients receiving 0.5 mg ml(-1) (74.7 mg) or 0.25 mg ml(-1) (74.1 mg) S-ketamine in oxycodone or oxycodone alone (81.9 mg) (mean difference: -20.6 mg; 95% confidence interval [CI]: -41 to -0.20; P = 0.048). A beneficial effect in mean change of pain intensity at rest was seen in the group receiving 0.75 mg ml(-1) S-ketamine in oxycodone PCA compared with patients receiving lower ketamine doses or oxycodone alone (standardized effect size: 0.17, 95% CI: 0.013-0.32, P = 0.033). The occurrence of adverse events was similar among the groups. Conclusions Oxycodone PCA containing S-ketamine as an adjunct at a ratio of 1: 0.75 decreased cumulative oxycodone consumption at 24 h after major lumbar spinal fusion surgery without additional adverse effects.Peer reviewe