Dexmedetomidine

Dexmedetomidine is a sedative medication used by intensive care units and anesthetists.

The sedative effects of the intranasal administration of dexmedetomidine in children undergoing surgeries compared to other sedation methods: A systematic review and meta-analysis.[Pubmed:28372674]

J Clin Anesth. 2017 May;38:33-39.

STUDY OBJECTIVE: Administration of intranasal Dexmedetomidine for sedation is comfortable and effective in children who are afraid of needles, and it offers efficient sedation similar to that of intravenous administration. We performed a systematic review and meta-analysis to evaluate the clinical effects of the pre-procedural administration of intranasal Dexmedetomidine. DESIGN: We identified randomized controlled trials (RCTs) that compared intranasal Dexmedetomidine administration to other administration methods of various sedatives or placebo from MEDLINE, EMBASE, Cochrane, KoreaMed and hand searches of trial registries. SETTING: Pediatrics who underwent interventional procedures and surgeries. PATIENTS: Children under the age of 18. INTERVENTIONS: Studies were included if they were compatible with the criteria that Dexmedetomidine was administered intranasally. MEASUREMENTS: We pooled data on the sedation status as the primary outcome and considered the behavioral score, blood pressure, heart rate and side effects to be secondary outcomes. Risk ratio (RR) and the standardized mean difference (SMD) with 95% confidence intervals (CIs) were calculated for dichotomous and continuous outcomes, respectively. MAIN RESULTS: This meta-analysis included 11 RCTs. The SMD for the sedative effects of intranasal Dexmedetomidine was -2.45 (random, 95% CI; -3.33, -1.58) for continuous outcomes and RR of unsatisfactory patient outcome was 0.42 (M-H, random 95% CI; 0.26, 0.68 I(2)=45%) for dichotomous outcomes compared to that of intranasal saline. The SMD for the sedative effects of intranasal Dexmedetomidine was -0.41 (random, 95% CI; -1.09, 0.27 I(2)=69%) for continuous outcomes and RR was 0.43 (M-H, random 95% CI; 0.32, 0.58 I(2)=0%) for dichotomous outcomes compared to that of per os benzodiazepines. CONCLUSIONS: This review suggests that intranasal Dexmedetomidine is associated with better sedative effects than oral benzodiazepines without producing respiratory depression, but it had a significantly delayed onset of effects.

Effect of Adding Dexmedetomidine to Ropivacaine on Ultrasound-Guided Dual Transversus Abdominis Plane Block after Gastrectomy.[Pubmed:28374183]

J Gastrointest Surg. 2017 Jun;21(6):936-946.

OBJECTIVES: Transversus abdominis plane (TAP) block is an analgesic technique. Adding Dexmedetomidine can enhance regional anesthesia. This study's aim was to evaluate whether Dexmedetomidine prolonged analgesic time of TAP block after gastrectomy. METHODS: Patients scheduled for gastrectomy were randomly assigned to receive a TAP block with saline (group S), ropivacaine (group R), or ropivacaine and Dexmedetomidine (group RD). Visual analogue scale (VAS) scores, postoperative nausea and vomiting (PONV) scores, sedation scores, tramadol consumption, ropivacaine concentration, and Quality of Recovery Questionnaire 40 (QoR-40) were recorded. RESULTS: Patients in group R and group RD had lower VAS scores 2, 4, 12, and 24 h after surgery compared with group S (P < 0.05). PONV scores were lower in group R and group RD compared with group S after 2, 12, 24, and 36 h (P < 0.05). Patients in group R and group RD required less tramadol and had better QoR-40 scores than those in group S (P < 0.05). The aforementioned variables and ropivacaine concentrations did not differ between group R and group RD (P > 0.05). Sedation scores were similar between three groups (P > 0.05). CONCLUSIONS: TAP block can provide analgesia and improve the quality of recovery. Adding Dexmedetomidine does not significantly improve the quality or duration of TAP block.

The Cardioprotective Effect of Dexmedetomidine in Rats Is Dose-Dependent and Mediated by BKCa Channels.[Pubmed:28375904]

J Cardiovasc Pharmacol. 2017 Apr;69(4):228-235.

The alpha-2 receptor agonist Dexmedetomidine (Dex) protects the heart against ischemia-reperfusion injury. We investigated the signaling cascade underlying Dex-induced acute cardioprotection, with special emphasis on large-conductance Ca2+-sensitive potassium (BKCa) channels. Rats were anesthetized with pentobarbital. Hearts were isolated, mounted on a Langendorff system and perfused with Krebs-Henseleit buffer. Hearts underwent 33 minutes of ischemia followed by 60 minutes of reperfusion. Before the beginning of ischemia, Dex was administered at different doses (0.1-30 nM) for characterization of a dose-effect relationship. In another set of experiments, Dex (3 nM) was administered together with the BKCa channel inhibitor paxilline and the connexin-43 inhibitor peptide Gap27. Also, the BKCa channel opener NS1619 was administered. In control animals, infarct size was 49% +/- 5%. Dex at 3-30 nM reduced infarct size to approximately 22%, whereas lower (0.1-1 nM) doses reduced infarct size to approximately 38%. Paxilline (1 muM) and GAP27 (6 muM) blocked the Dex-induced cardioprotection. NS1619 (10 muM) reduced infarct size to about the same magnitude as did the higher doses of Dex. Functional heart parameters and coronary flow were not different between the study groups. In male rats, the Dex-induced protection against ischemia-reperfusion injury involves connexin-43 and activation of BKCa channels.