Analgesic efficacy of intravenous naloxone for the treatment of postoperative pruritus: a meta-analysis.

OBJECTIVES: Pruritus may be a significant problem for patients in the postoperative period. There are many options for the treatment of pruritus including intravenous (IV) naloxone. However, it is not clear whether the use of IV naloxone may also affect analgesia or other opioid-related side effects. The authors have performed a systematic review to further examine this issue. METHODS: Systematic literature searches of the National Library of Medicine's PubMed and EMBASE databases were conducted using terms related to postoperative use of IV naloxone. Only randomized controlled trials comparing IV naloxone used either as a continuous infusion or part of an IV patient-controlled analgesia (PCA) regimen after surgical procedures were considered. The data on pertinent study characteristics and relevant outcomes were extracted from accepted articles. There was no restriction on language for inclusion. Meta-analysis was performed using the Review Manager 4.2.10 (The Cochrane Collaboration, 2004). A random effects model was used. RESULTS: The literature searches yielded eight articles that met all inclusion criteria. There were a total of 424 subjects in the naloxone group and 376 in the saline group. The authors found that the use of naloxone was associated with a decreased risk for pruritus (odds ratio [OR] = 0.40, 95% confidence interval [CI] = 0.21-0.79, p = 0.006] and nausea [OR = 0.62, 95% CI = 0.43-0.89, p = 0.009]. However, the use of IV naloxone (vs no naloxone) did not significantly influence the risk of postoperative emesis [OR = 0.97, 95% CI = 0.70-1.33, p = 0.83], opioid consumption [OR = 0.29, 95% CI = -3.54-4.13, p = 0.88], or sedation [OR = 0.82, 95% CI = 0.38-1.74, p = 0.60]. Finally, the use of IV naloxone did not appear to be associated with any significant change in visual analog score pain scores at 24 hours postoperatively (weighted mean difference = -0.14, 95% CI = -0.50-0.23, p = 0.46). CONCLUSIONS: Our pooled analysis examining the analgesic efficacy of IV naloxone (either as a continuous infusion or IV PCA) revealed that naloxone was associated with a decrease in pruritus and nausea without any increase in pain scores. When compared with controls, the use of IV naloxone was not associated with any significant changes in opioid consumption or with the risk of sedation or emesis.

Analgesic efficacy of ultrasound-guided regional anesthesia: a meta-analysis.

STUDY OBJECTIVE: To determine if the use of ultrasound guidance (vs non-ultrasound techniques) improves the success rate of nerve blocks. DESIGN: Meta-analysis of randomized controlled trials (RCTs) in the published literature. SETTING: University medical center. MEASUREMENTS: 16 RCTs of patients undergoing elective surgical procedures were studied. Patients underwent ultrasound-guided or non-ultrasound techniques (nerve stimulation, surface landmark) for peripheral nerve blocks. Success rates were measured. MAIN RESULTS: Ultrasound guidance (vs all non-ultrasound techniques) was associated with a significant increase in the success rate of nerve blocks [relative risk (RR) = 1.11 (95% confidence interval [CI]: 1.06 to 1.17, P < 0.0001]). When compared with nerve stimulator techniques only, ultrasound guidance was still associated with an increase in the success rate (RR = 1.11 [95% CI: 1.05 to 1.17, P = 0.0001]). For specific blocks, ultrasound guidance (vs all non-ultrasound) was associated with a significant increase in successful brachial plexus (all) nerve blocks (RR = 1.11 [95% CI: 1.05 to 1.20, P = 0.0001]), sciatic popliteal nerve block (RR = 1.22 [95% CI: 1.08 to 1.39, P = 0.002]) and brachial plexus axillary nerve block (RR = 1.13 [95% CI: 1.00 to 1.26, P = 0.05]) but not brachial plexus infraclavicular nerve block (RR = 1.25 [95% CI: 0.88 to 1.76, P = 0.22]). CONCLUSIONS: Ultrasound-guided peripheral nerve block is associated with an increased overall success rate when compared with nerve stimulation or other methods. Ultrasound-guided techniques also increase the success rate of some specific blocks.

Dexmedetomidine and proprofol in complex microlaryngeal surgery in infants.

We describe the case of an infant undergoing endoscopic repair of a laryngeal cleft where the combination of dexmedetomidine and propofol infusions was used as the anesthetic technique. With this regimen, endotracheal intubation was unnecessary during the perioperative period, the procedure lasted approximately 3h, and the child recovered uneventfully. Historically, the techniques used for microlaryngeal surgery involve the use of intermittent endotracheal intubation and insufflation of halogenated anesthetics to the oropharynx. Given the potential benefits of a technique that obviates the need for endotracheal intubation during microlaryngeal surgery and prevents insufflation of halogenated anesthetics in an open environment, the combination of propofol and dexmedetomidine should be considered as a viable and desirable anesthetic option for infants undergoing complex microlaryngeal surgery.