Efficacy of intrathecal dexmedetomidine in prevention of shivering in patients undergoing transurethral prostatectomy: A randomized controlled trial

The Effect of Dexmedetomidine Prescription on Shivering during Operation in the Spinal Anesthesia Procedures of Selective Orthopedic Surgery of the Lower Limb in Addicted Patients

Background

Shivering during a surgery is common. Recently, Alpha-D-agonist dexmedetomidine has been used to control and prevent shivering during and after surgery. However, the anti-shivering effects of this drug in people are unknown with substance abuse. The purpose of this study was to investigate the anti-shivering effect of this drug in addicted individuals.

Methods

After obtaining the required criteria, the criteria were randomized in 2 groups, dexmedetomidine and normal saline (each group n = 30), and were matched in age and sex. The dexmedetomidine 0.5 mg/kg/h was given to one group and normal saline infusion was given to the other group as a placebo immediately after induction of anesthesia and before surgery for lower limb lesions. During the operation, patients were monitored for shivering as well as vital signs and arterial oxygen saturation. In addition, after surgery, patients were evaluated for clinical side effects.

Results

The results showed that systolic blood pressure was significantly lower in the dexmedetomidine group at 30 minutes to 150 minutes after injection during the operation (P < 0.01). There was no significant difference between the 2 groups at the other times. In intra-group comparisons in both groups, diastolic pressure drop was significantly decreased to 90 minutes after surgery. In general, at other times in each group, diastolic pressure changes were not significant compared to preoperative. In between group comparisons, the mean heart rate was significantly lower in the dexmedetomidine group at 30 minutes and 60 minutes compared to the control group. In addition, at other times, its lower values were not significantly different with the control group. The 2 groups did not show significant differences in the number of breaths per minute or as the intra-group (P > 0.05), although, the average respiratory rate per minute in the dexmedetomidine group was lower. Decreased temperature of the tympanic curvature was significantly lower in the DEX group at 10 and 60 minutes after surgery than the control group (P < 0.001). Arterial oxygen saturation was more than 97% in both groups before and after operation, and no difference was observed between the 2 groups.

Conclusions

Prescribing dexmedetomidine during spinal anesthesia in patients with substance abuse can significantly decrease the incidence of shivering during surgery while not having adverse effects on hemodynamics of patients and can be used as a safe and effective drug for this purpose.

Isobaric ropivacaine with or without dexmedetomidine for surgery of neck femur fracture under subarachnoid block

Background and Aims:

Dexmedetomidine has a promising role as an intrathecal adjuvant. However it's role as an adjuvant to ropivacaine has not been evaluated extensively. This study is designed to find out the effect of addition of dexmedetomidine 5 μg to isobaric ropivacaine 18.75 mg on block characteristics and hemodynamic parameters in patients undergoing surgeries for fracture neck of femur under subarachnoid block (SAB).

Material and Methods:

Sixty-one American Society of Anesthesiologists (ASA) Class I or II patients between 18–60 years undergoing surgeries for fracture neck of femur under SAB were recruited and randomized into two groups. Thirty patients in Group RN received 2.5 ml isobaric ropivacaine 0.75% (18.75 mg) with 0.5 ml normal saline (NS) to make a total volume of 3 ml, while 31 patients in Group RD received 2.5 ml isobaric ropivacaine 0.75% with dexmedetomidine 5 μg diluted with NS to make a total volume of 3 ml. The block characteristics, hemodynamic parameters, and side effects were recorded in both the groups.

Results:

Patients in Group RD had significantly longer duration of sensory block (202.90 ± 50.2 min) compared to Group RN (157.33 ± 31.6 min), P < 0.001. Time to first rescue analgesia request was significantly longer in the Group RD compared to Group RN (265.16 ± 71.4 min vs 203.67 ± 35.6 min, respectively) (P < 0.001). However, the sensory block onset, maximum block height, time to two dermatomal regression, and motor block intensity remained unaltered. Incidence of side effects like hypotension, bradycardia, nausea, vomiting, and shivering were statistically similar in both the groups.

Conclusion:

Addition of 5 μg dexmedetomidine enhances the analgesic effect of intrathecal 18.75 mg isobaric ropivacaine for the conduct of fracture neck of femur surgeries with minimal adverse events.

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

BACKGROUND

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.

METHODS

This systematic review and meta-analysis was registered in PROSPERO [www.crd.york.ac.uk/PROSPERO] 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.

RESULTS

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.

CONCLUSIONS

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.