Dexmedetomidine as a neuraxial adjuvant for prevention of perioperative shivering: Meta-analysis of randomized controlled trials

<div><p>Background</p><p>Dexmedetomidine, a highly selective α2-adrenoceptor agonist, has been investigated for anti-shivering effects in some trials. This current meta-analysis was conducted to evaluate the effectiveness of dexmedetomidine as a neuraxial adjuvant in preventing perioperative shivering.</p><p>Methods</p><p>This systematic review and meta-analysis was registered in PROSPERO [<a href="http://www.crd.york.ac.uk/PROSPERO" target="_blank">www.crd.york.ac.uk/PROSPERO</a>] with the unique identification number CRD42017055991. The electronic databases PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) were searched to select high-quality randomized controlled trials (RCTs) that evaluated the anti-shivering efficacy for neuraxial application dexmedetomidine as local anesthetic adjuvant. Effects were summarized using pooled risk ratios (RRs), weighed mean differences (MDs), or standardized mean differences (SMDs) and corresponding 95% confidence intervals (Cls) with random effect model. Heterogeneity assessment, sensitivity analysis, and publication bias were performed. The primary outcome was perioperative shivering.</p><p>Results</p><p>A total of 1760 patients from 24 studies were included in this meta-analysis. Compared with the placebo, dexmedetomidine reduced the incidence of perioperative shivering (RR: 0.34; 95% Cl: 0.21 to 0.55; P < 0.00001), with a maximum effective dose of 5μg via subarachnoid space injection (RR: 0.55; 95% CI: 0.32 to 0.92; P = 0.02), especially in cesarean section (RR: 0.20; 95% CI: 0.09 to 0.45; P = 0.0001). Dexmedetomidine also could improve the characteristics of the block, with an increase only in the incidence of bradycardia (RR: 2.11; 95% CI: 1.23 to 3.60; P = 0.006). No significant difference could be found compared dexmedetomidine with other adjuvants, except morphine.</p><p>Conclusions</p><p>This meta-analysis shows that dexmedetomidine as a neuraxial adjuvant had statistically significant efficacy on prevention of perioperative shivering. Moreover, dexmedetomidine could improve the characteristics of the block. However, the potential induction of bradycardia should be taken seriously.</p></div

Results of subgroup analysis of the incidence of perioperative shivering compared dexmedetomidine 5μg with dexmedetomidine 10μg.

<p>Results of subgroup analysis of the incidence of perioperative shivering compared dexmedetomidine 5μg with dexmedetomidine 10μg.</p

Flow diagram of the inclusion and exclusion processes.

<p>Flow diagram of the inclusion and exclusion processes.</p

Results of subgroup analysis of the incidence of perioperative shivering by doses of spinal dexmedetomidine.

<p>Results of subgroup analysis of the incidence of perioperative shivering by doses of spinal dexmedetomidine.</p

Results of subgroup analysis of the incidence of perioperative shivering in cesarean section.

<p>Results of subgroup analysis of the incidence of perioperative shivering in cesarean section.</p

Risk of bias assessment of the included studies.

<p>Risk of bias assessment of the included studies.</p

Results of subgroup analysis of the incidence of perioperative shivering by routes of dexmedetomidine administration.

<p>Results of subgroup analysis of the incidence of perioperative shivering by routes of dexmedetomidine administration.</p

Closed-Loop Control Better than Open-Loop Control of Profofol TCI Guided by BIS: A Randomized, Controlled, Multicenter Clinical Trial to Evaluate the CONCERT-CL Closed-Loop System

<div><p>Background</p><p>The CONCERT-CL closed-loop infusion system designed by VERYARK Technology Co., Ltd. (Guangxi, China) is an innovation using TCI combined with closed-loop controlled intravenous anesthesia under the guide of BIS. In this study we performed a randomized, controlled, multicenter study to compare closed-loop control and open-loop control of propofol by using the CONCERT-CL closed-loop infusion system.</p><p>Methods</p><p>180 surgical patients from three medical centers undergone TCI intravenous anesthesia with propofol and remifentanil were randomly assigned to propofol closed-loop group and propofol opened-loop groups. Primary outcome was global score (GS, GS = (MDAPE+Wobble)/% of time of bispectral index (BIS) 40-60). Secondary outcomes were doses of the anesthetics and emergence time from anesthesia, such as, time to tracheal extubation.</p><p>Results</p><p>There were 89 and 86 patients in the closed-loop and opened-loop groups, respectively. GS in the closed-loop groups (22.21±8.50) were lower than that in the opened-loop group (27.19±15.26) (p=0.009). The higher proportion of time of BIS between 40 and 60 was also observed in the closed-loop group (84.11±9.50%), while that was 79.92±13.17% in the opened-loop group, (p=0.016). No significant differences in propofol dose and time of tracheal extubation were observed. The frequency of propofol regulation in the closed-loop group (31.55±9.46 times/hr) was obverse higher than that in the opened-loop group (6.84±6.21 times/hr) (p=0.000).</p><p>Conclusion</p><p>The CONCERT-CL closed-loop infusion system can automatically regulate the TCI of propofol, maintain the BIS value in an adequate range and reduce the workload of anesthesiologists better than open-loop system.</p><p>Trial Registration</p><p>ChiCTR <a href="http://www.chictr.org.cn/showproj.aspx?proj=9931/ChiCTR-OOR-14005551" target="_blank">ChiCTR-OOR-14005551</a></p></div

Heat map of microRNA microarray expression data from hippocampus samples of 3 groups.

<p>The expression of miRNAs is hierarchically clustered on the y axis, and hippocampus samples of 3 groups are hierarchically clustered on the x axis. Number with C represent control group, number with 2h represent 2-hour group, number with 6h means 6-hour group. The legend on the right indicates the miRNA represented in the corresponding row. The color scale on the right show the relative miRNA expression, green means downregulation, while red means upregulation, n = 4 per group.</p

Sequences of the primers used in the SYBR-green-based quantitative RT-PCR validation.

<p>Sequences of the primers used in the SYBR-green-based quantitative RT-PCR validation.</p