Effect of perineural dexmedetomidine on the quality of supraclavicular brachial plexus block with 0.5% ropivacaine and its interaction with general anaesthesia

Efficacy of dexmedetomidine combined with ropivacaine on postoperative analgesia and delirium in elderly patients with total knee arthroplasty

This study aimed to investigate the impact of dexmedetomidine combined with ropivacaine on continuous femoral nerve block (CFNB) in postoperative analgesia and delirium in elderly patients with total knee arthroplasty (TKA). A total of 120 patients who undergone TKA were randomly assigned into group D + R (dexmedetomidine combined with ropivacaine) and group R (only ropivacaine), with 60 cases in each group. The pain scores at rest and exercise at 6 h, 12 h, 24 h, and 48 h postoperatively. The occurrence of delirium on Day 1, Day 2, and Day 3 postoperatively were measured, and the sleep quality was evaluated before surgery, the night of surgery, and 24 h postoperatively to observe the occurrence of postoperative complications. The Visual analogu scale (VAS) of group D + R at 12 h, 24 h, and 48 h postoperatively were lower than those of group R in both rest and exercise states. The incidence of postoperative delirium in group D + R was lower than that in group R on Day 1 and Day 2. Pittsburgh sleep quality index (PSQI) scores in group D + R were lower than those in group R. There was no significant difference in postoperative adverse reactions between the two groups. Dexmedetomidine combined with ropivacaine improves postoperative analgesia and sleep quality, and alleviates the occurrence of postoperative delirium in elderly patients with TKA.

The effect of adjuvants added to local anaesthetics for single-injection upper extremity peripheral regional anaesthesia: A systematic review with network meta-analysis of randomised trials

BACKGROUND

Peripheral regional anaesthesia is frequently used for upper extremity surgery. To prolong the duration of analgesia, adjuvants can be added to single-injection local anaesthetics. Despite attempts to compare several adjuvants in pairwise meta-analyses, a comprehensive comparison is still missing.

OBJECTIVE

The objective of this network meta-analysis was to determine the effectiveness of adjuvants in upper extremity peripheral nerve blocks.

DESIGN

A systematic review of randomised controlled trials with network meta-analyses.

DATA SOURCES

A literature search in Embase, CENTRAL, MEDLINE and Web of Science was performed up to March 2023.

ELIGIBILITY CRITERIA

Randomised trials comparing different adjuvants injected perineurally in peripheral upper extremity nerve blocks were eligible. Frequentist network meta-analysis was conducted using a random effects model with physiological saline as the comparator. The primary endpoint was the ratio of means (ROM) of the duration of analgesia.

RESULTS

The review included 242 randomised controlled trials with a total of 17 391 patients. Twenty-eight adjuvants were compared in the largest networks. Most network estimations consisted of a high proportion of direct evidence. Fourteen adjuvants increased the duration of analgesia significantly by the following factors, ROM [95% confidence interval (CI)]: dexamethasone 1.95 (1.79 to 2.13), buprenorphine 1.83 (1.51 to 2.24), butorphanol 1.84 (1.41 to 2.39), potassium chloride 1.89 (1.15 to 3.11), dexmedetomidine 1.70 (1.59 to 1.81), sufentanil 1.70 (1.27 to 2.29), ketorolac 1.68 (1.24 to 2.27), midazolam 1.55 (1.24 to 1.94), tramadol 1.52 (1.32 to 1.75), nalbuphine 1.50 (1.30 to 1.72), morphine 1.43 (1.09 to 1.88), magnesium sulfate 1.42 (1.20 to 1.67), clonidine 1.36 (1.24 to 1.50) and fentanyl 1.23 (1.08 to 1.40). Inconsistency in network meta-analysis was substantial. Overall side effect rates were low with all adjuvants.

CONCLUSION

The best interventions to prolong the duration of analgesia were dexamethasone, followed by dexmedetomidine, opioids, electrolytes, ketorolac and midazolam. There are general concerns about the quality of underlying studies and the risk of publication bias.

TRIAL REGISTRATION

PROSPERO 2018 CRD42018115722.

Alpha2 -receptor agonists as adjuvants for brachial plexus nerve blocks-A systematic review with meta-analyses

BACKGROUND

We review the efficacy and safety of dexmedetomidine and clonidine as perineural or systemic adjuvants for brachial plexus blocks (BPB).

METHODS

We included randomised controlled trials on upper limb surgery with BPBs in adults, comparing dexmedetomidine with clonidine or either drug with placebo. The primary outcome was duration of analgesia. Secondary outcomes included adverse and serious adverse events. The review was conducted using Cochrane standards, trial sequential analyses (TSA) and Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

We included 101 trials with 6248 patients. Overall, duration of analgesia was prolonged with both clonidine (176 min [TSA adj. 95% CI: 118, 205, p < .00001; 33 trials]) and dexmedetomidine (292 min [TSA adj. 95% CI: 245 329, p < .00001; 53 trials]), but was longer for dexmedetomidine than clonidine (205 min [TSA adj. 95% CI: 157, 254, p < .00001; 19 trials]). Compared with placebo, dexmedetomidine was associated with bradycardia (RR 4.2 [95% CI 2.2, 8.3]), and both clonidine (RR 4.5 [95% CI 1.1, 18.3]) and dexmedetomidine (RR 3.9 [95% CI 2.0, 7.5]) were associated with hypotension. Serious adverse events were mostly related to block technique. GRADE-rated quality of evidence was low or very low.

CONCLUSION

Alpha2-receptor agonists used as adjuvants for BPBs lead to a prolonged duration of analgesia, with dexmedetomidine as the most efficient. Alpha2-receptor agonists were associated with increased risk of cardiovascular adverse events. The quality of evidence was low to very low.

Levobupivacaine versus levobupivacaine plus dexmedetomidine in transversus abdominis plane block in patients undergoing abdominal aortic surgery

Background:

Severe postoperative pain is a major dilemma for patients undergoing abdominal aortic surgery. Transversus abdominis plane (TAP) block has been described a successful pain management technique after major abdominal surgery. Dexmedetomidine was proved to enhance the analgesic action of local anesthetics.

Aim:

This study was aimed to assess the impact of adding dexmedetomidine to levobupivacaine during TAP block in patients undergoing abdominal aortic operations.

Patients and Methods:

We included 114 patients in this prospective trial, and they were enrolled into two groups; the L group received levobupivacaine only, and the LD group received levobupivacaine plus dexmedetomidine. The block was performed before anesthetic induction. Postoperative pain score was our main outcome.

Statistical Analysis:

The collected data were tabulated and analyzed through the SPSS software program IBM's Statistical Package for the Social Sciences (SPSS) statistics for Windows (version 25, 2017) (IBM Corporation, Armonk, NY, USA). The categorical data were expressed as numbers and percentages and then compared using the Chi-square test. The continuous data were expressed as mean and standard deviation if normally distributed, or median and range if abnormally distributed. The former data were compared through the one-way ANOVA, while the latter were compared through the Kruskal–Wallis test. Any P < 0.05 was considered statistically significant.

Results:

Group LD showed significantly earlier sensory blocks compared to the other group. Postoperative pain scores were comparable between the two groups for the initial 4 h following the surgery. Adjuvant dexmedetomidine was associated with better pain scores for the subsequent 12 h compared to Group L. The duration till the first analgesic request showed a significant increase in the LD group (13.3 vs. 11.09 h in Group L). In addition, the same group showed a significant decline in their opioid consumption after the operation (48.95 μg vs. 72.63 μg in the other group). Postoperative nausea and vomiting were significantly increased in Group L.

Conclusion:

Adjuvant dexmedetomidine has a significant beneficial impact on postoperative analgesic profile. Its use as an adjuvant to peripheral and neuraxial nerve blocks should be recommended in pain management practice.

Optimal dose of perineural dexmedetomidine to prolong analgesia after brachial plexus blockade: a systematic review and Meta-analysis of 57 randomized clinical trials

Background and Objectives

Peripheral injection of dexmedetomidine (DEX) has been widely used in regional anesthesia to prolong the duration of analgesia. However, the optimal perineural dose of DEX is still uncertain. It is important to elucidate this characteristic because DEX may cause dose-dependent complications. The aim of this meta-analysis was to determine the optimal dose of perineural DEX for prolonged analgesia after brachial plexus block (BPB) in adult patients undergoing upper limb surgery.

Method

A search strategy was created to identify suitable randomized clinical trials (RCTs) in Embase, PubMed and The Cochrane Library from inception date to Jan, 2021. All adult patients undergoing upper limb surgery under BPB were eligible. The RCTs comparing DEX as an adjuvant to local anesthetic (LA) with LA alone for BPB were included. The primary outcome was duration of analgesia for perineural DEX. Secondary outcomes included visual analog scale (VAS) in 12 and 24 h, consumption of analgesics in 24 h, and adverse events.

Results

Fifty-seven RCTs, including 3332 patients, were identified. The subgroup analyses and regression analyses revealed that perineural DEX dose of 30-50 μg is an appropriate dosage. With short−/intermediate-acting LAs, the mean difference (95% confidence interval [CI]) of analgesia duration with less than and more than 60 μg doses was 220.31 (153.13–287.48) minutes and 68.01 (36.37–99.66) minutes, respectively. With long-acting LAs, the mean differences (95% CI) with less than and more than 60 μg doses were 332.45 (288.43–376.48) minutes and 284.85 (220.31–349.39) minutes.

Conclusion

30-50 μg DEX as adjuvant can provides a longer analgesic time compared to LA alone and it did not increase the risk of bradycardia and hypotension.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01452-0.

Comparison of Dexmedetomidine and Dexamethasone as Adjuvants to Ultra-Sound Guided Interscalene Block in Arthroscopic Shoulder Surgery: A Double-Blinded Randomized Placebo-Controlled Study

BACKGROUND

Interscalene block is one of the popular methods for decreasing pain and analgesic consumption after shoulder arthroscopic surgeries.

OBJECTIVES

The objective is to compare the analgesic duration of effects of dexmedetomidine and dexamethasone as adjuvants to 0.5% ropivacaine in ultrasound-guided interscalene blocks for arthroscopic shoulder surgery in an ambulatory setting.

METHODS

In this randomized controlled trial, 117 adult patients candidate for ambulatory arthroscopic shoulder surgery under general anesthesia were divided into three groups to perform an ultra-sound guided interscalene block before the surgery. The ropivacaine (control) group received ropivacaine 0.5% 20 mL, group Dexamethasone received ropivacaine 0.5% 20 mL plus 4mg dexamethasone, and group dexmedetomidine received ropivacaine 0.5% 20 mL plus 75 mcg of dexmedetomidine. Time to return of sensory function, of motor function, of first pain sensation, amount of opioid medication consumed at 24 hours and 48 hours post-operatively were measured.

RESULTS

The 24-hour median (25th- 75th percentile) opioid consumption in morphine equivalents was similar between groups 22.5 mg (10 - 30), 15 mg (0 - 30), and 15 mg (0 - 20.6) in the ropivacaine, dexmedetomidine, and dexamethasone groups, respectively (P = 0.130). The median (25th- 75th percentile) 48 hours post-operatively, the median opioid consumption in morphine equivalents was 40 mg (25 - 67.5) in the ropivacaine group, 30 mg (22 - 50.6) in the dexamethasone group, and 52.5 mg (30 - 75) in the dexmedetomidine group (P = 0.278). The median 24-hour pain scores were 6 (5 - 8) in the ropivacaine control group, 7 (5.5 - 8) in the dexamethasone group, and 7 (4 - 9) in the dexmedetomidine group (P = 0.573).

CONCLUSIONS

There was no statistical difference in opioid consumption at 24 and 48 hours post-operatively when comparing dexmedetomidine, dexamethasone, and no adjuvant. However, intraoperative opioid use was significantly lower with dexmedetomidine compared to dexamethasone and plain 0.5% ropivacaine. The safe side effect profile of dexmedetomidine makes it a reasonable alternative as an adjuvant for peripheral nerve blockade when dexamethasone use may be contraindicated.

Comparison of morphine, dexmedetomidine and dexamethasone as an adjuvant to ropivacaine in ultrasound-guided supraclavicular brachial plexus block for postoperative analgesia-a randomized controlled trial

Background and Aims:

An ideal adjuvant to local anesthetic in a nerve block should prolong the duration of analgesia, and hasten the onset of sensory and motor blockade without significant adverse effects. The aim of this study was to compare morphine, dexmedetomidine, and dexamethasone as an additive to ropivacaine in ultrasound-guided supraclavicular brachial plexus block (SBPB) for postoperative analgesia.

Material and Methods:

In this randomized, double-blinded study, 150 patients undergoing upper extremity surgery were randomly divided into three groups: group A (morphine 5 mg), group B (dexmedetomidine 50 μg), and group C (dexamethasone 8 mg). The additives were added to 30 ml of 0.5% ropivacaine solution and administered in SBPB. The duration of postoperative analgesia, onset of sensory and motor blockade, sedation, and adverse effects were observed. The pain was assessed by visual analog scale (VAS) and sedation by Ramsay sedation score. The duration of postoperative analgesia was taken as time consumed from block completion to administration of rescue analgesia (VAS >3).

Results:

The demographic profile was similar in both groups. The duration of analgesia was significantly longer in dexamethasone (867.2 ± 217.6 min) than morphine (739. 2 ± 162.5 min) and dexmedetomidine (654.2 ± 179.9 min) (P < 0.001). The onset of sensory and motor blockade was quicker with dexmedetomidine than dexamethasone and morphine. Three cases of block failure were reported with morphine. No major adverse effects were reported.

Conclusion:

Dexamethasone is an ideal adjuvant to ropivacaine in brachial plexus block to prolong postoperative analgesia and devoid of adverse effects. Dexmedetomidine has a quicker onset of sensory and motor blockade.

Fentanyl and clonidine as adjuncts to a mixture of local anesthetics in potentiating postoperative analgesia in supraclavicular block: A randomized controlled study

Background:

Brachial plexus block is popular for upper limb surgeries as it is effective for postoperative analgesia.

Aims:

The aim of the study was to compare fentanyl and clonidine as adjuncts to a mixture of local anesthetics in potentiating postoperative analgesia in the supraclavicular block.

Materials and Methods:

Sixty patients of the American Society of Anesthesiologist I and II undergoing upper limb surgeries lasting more than 30 min were included and randomly divided into two groups of 30 each. In clonidine (C) group, patients received 10 ml of 0.5% bupivacaine + 20 ml of 2% lignocaine with adrenaline (1:200,000) and 1 μg/kg clonidine diluted till 35 cc with normal saline. In fentanyl (F) group, patients received 10 ml of 0.5% bupivacaine + 20 ml of 2% lignocaine with adrenaline (1:200,000) and 1 μg/kg fentanyl diluted till 35 cc with normal saline. Patients were observed for onset and duration of sensory and motor blockade, duration of analgesia, postoperative pain, and adverse effects.

Results:

The mean onset of sensory block was faster in Group F (8.43 ± 2.897 min) as compared to 13.17 ± 2.451 min in Group C. The difference between the two groups was statistically strongly significant (P < 0.0001). There was a significant reduction in the onset of motor block in Group F (14.67 ± 1.84 min) compared to (18.17 ± 2.45 min) Group C with P < 0.0001 (statistically strongly significant). There was a significant increase in the duration of analgesia in Group C (16.63 ± 2.04 h) compared to Group F (8.79 ± 1.50 h) with P < 0.0001. There was bradycardia (pulse did not fall below 60) in two patients of Group C (treated with atropine intravenous [i.v.]). Two patients of Group F complained of nausea and vomiting once in the early hours of surgery for which ondansetron i.v. was given. There were no significant side effects in either of the groups.

Conclusion:

Both clonidine and fentanyl establish a good safety profile. Fentanyl ensures a faster onset of sensory and motor blockade, while clonidine ensures a longer duration of sensory and motor blockade as well as prolonged analgesia.

Perineural and intravenous dexamethasone and dexmedetomidine: network meta-analysis of adjunctive effects on supraclavicular brachial plexus block

Both perineural and intravenous dexamethasone and dexmedetomidine are used as local anaesthetic adjuncts to enhance peripheral nerve block characteristics. However, the effects of dexamethasone and dexmedetomidine based on their administration routes have not been directly compared, and the relative extent to which each adjunct prolongs sensory blockade remains unclear. This network meta-analysis sought to compare and rank the effects of perineural and intravenous dexamethasone and dexmedetomidine as supraclavicular block adjuncts. We sought randomised trials investigating the effects of adding perineural and intravenous dexamethasone or dexmedetomidine to long-acting local anaesthetics on supraclavicular block characteristics, including time to block onset and durations of sensory, motor and analgesic blockade. Data were compared and ranked according to relative effectiveness for each outcome. Our primary outcome was sensory block duration, with a 2-h difference considered clinically important. We performed a frequentist analysis, using the GRADE framework to appraise evidence. One-hundred trials (5728 patients) were included. Expressed as mean (95%CI), the control group (local anaesthetic alone) had a duration of sensory block of 401 (366-435) min, motor block duration of 369 (330-408) min and analgesic duration of 435 (386-483) min. Compared with control, sensory block was prolonged most by intravenous dexamethasone [mean difference (95%CI) 477 (160-795) min], followed by perineural dexamethasone [411 (343-480) min] and perineural dexmedetomidine [284 (235-333) min]. Motor block was prolonged most by perineural dexamethasone [mean difference (95%CI) 294 (236-352) min], followed by intravenous dexamethasone [289 (129-448)min] and perineural dexmedetomidine [258 (212-304)min]. Analgesic duration was prolonged most by perineural dexamethasone [mean difference (95%CI) 518 (448-589) min], followed by intravenous dexamethasone [478 (277-679) min] and perineural dexmedetomidine [318 (266-371) min]. Intravenous dexmedetomidine did not prolong sensory, motor or analgesic block durations. No major network inconsistencies were found. The quality of evidence for intravenous dexamethasone, perineural dexamethasone and perineural dexmedetomidine for prolongation of supraclavicular sensory block duration was 'low', 'very low' and 'low', respectively. Regardless of route, dexamethasone as an adjunct prolonged the durations of sensory and analgesic blockade to a greater extent than dexmedetomidine. Differences in block characteristics between perineural and intravenous dexamethasone were not clinically important. Intravenous dexmedetomidine did not affect block characteristics.

Efficacy of multimodal analgesia with perineural buprenorphine or dexmedetomidine for surgeries performed under ultrasound-guided infraclavicular brachial plexus block

Background and Aims:

Perineural adjuvants when used as a part of multimodal analgesia (MMA) will maximize the quality and duration of analgesia of the nerve blocks. In the present study, we compared the duration of postoperative analgesia and other block characteristics of two groups of MMA comprising either perineural buprenorphine or dexmedetomidine in the upper limb surgeries performed under ultrasound-guided (US-guided) infraclavicular brachial plexus blocks.

Material and Methods:

A total of 100 adult patients undergoing elective upper limb orthopedic surgery under US-guided infraclavicular brachial plexus block were randomly divided into two groups. Group I received 150 μg buprenorphine and Group II received 50 μg dexmedetomidine, perineurally added to 30 ml of 0.375% bupivacaine. Both groups also received tramadol 50 mg IV, dexamethasone 4 mg IV, and diclofenac 75 mg infusion as part of MMA. Both groups were compared for the duration of postoperative analgesia, block characteristics, and incidence of adverse effects.

Results:

The duration of postoperative analgesia was significantly prolonged in Group II (937.6 ± 179.1 min vs 1280.4 ± 288.8 min). The onset of sensory and motor blocks was shorter in Group II (P < 0.05). The duration of sensory and motor blocks was significantly prolonged in Group II (P < 0.05). The number of rescue analgesics required in the first 24 hours was less in Group II (1.98 ± 0.62 vs 0.8 ± 0.64). Although heart rate and blood pressure levels were lower in Group II, all patients were hemodynamically stable.

Conclusion:

For surgeries under brachial plexus block, perineural dexmedetomidine when used as a part of MMA provided a prolonged duration of postoperative analgesia and improved block characteristics than perineural buprenorphine.

The effect of dexmedetomidine in coracoid approach brachial plexus block under dual stimulation

BACKGROUND

Coracoid approach brachial plexus block (CABPB) is safe and effective for clinical anesthesia and analgesia. Dual stimulation can enhance the block effect of CABPB when using nerve stimulator. Dexmedetomidine is a highly selective α-adrenoceptor agonist and it can prolong the duration of anesthesia when it is added into local anesthetics. The aim of this study was to assess the effects of dexmedetomidine on the duration of anesthesia and the effective postoperative analgesia time when it was mixed with ropivacaine for CABPB under dual stimulation.

METHODS

A total of 60 patients were randomly assigned into 2 groups (groups D and C), 30 patients in each group. CABPB were guided by nerve stimulator under dual stimulation. Each patient received 40 mL of 0.375% ropivacaine (group C), or 40 mL of 0.375% ropivacaine mixed with 1 μg/kg dexmedetomidine (group D). The duration of anesthesia, the effective postoperative analgesia time, sensory and motor block onset time, visual analog scale (VAS), and the cumulative dose of rescue tramadol were recorded.

RESULTS

Twenty-eight patients in each group were analyzed. The duration of anesthesia was longer in group D as compared with group C (759 vs 634 minutes, P < .05) and the effective postoperative analgesia time was longer in group D as compared with group C (986 vs 789 minutes, P < .05) too. The onset time of sensory and motor blocks were not significantly different between the 2 groups (P > .05). The VAS was similar in the 2 groups at 6 and 12 hours after block (P > .05), but it was lower in group D at 24 hours after block as compared to group C (P < .05). The cumulative dose of rescue tramadol during the first 48 hours postoperative period was significantly lower in group D as compared to group C (P < .05). No significant changes were observed in vital signs in either group.

CONCLUSION

The addition of 1 μg/kg dexmedetomidine to ropivacaine extends the duration of anesthesia and the effective postoperative analgesia time for CABPB under dual stimulation. The VAS at 24 hours after block and the demand for rescue tramadol during the first 48 hours postoperative period are lower as well without side effects in the study group.(Registered in ClinicalTrials.gov id. NCT02961361).

Risks and benefits of pre-operative dexmedetomidine in oral and maxillofacial surgeries: a systematic review

INTRODUCTION

Oral and maxillofacial surgeries might induce anxiety and pain to the patients. Sedative agents are one of the best ways for eliminating such consequences. Dexmedetomidine (DEX) is a recent sedative agent which presents higher sedative quality with greater specificity than other drugs. The aim of present paper is to evaluate the risks and benefits of administrating DEX during oral and maxillofacial surgeries by reviewing high quality released articles. Areas covered: Searches on PubMed, Scopus and Web of Science databases were completed with focus on randomized controlled trials (RCT). Related articles, from 2000 to 2015, were selected based on inclusion criteria and quality assessments factors. Full texts of the selected articles were screened and their significant information were gathered for judgments. Expert opinion: 17 RCTs on a total of 765 patients were screened. Some of the difficulties during reviewing the articles were: different pharmacokinetic and pharmacodynamics of drugs when combined with DEX, different time spots and method of monitoring, including studies on both minor and major surgeries for better data collection. Recent researches are going to focus on application of DEX for in-office procedures because of its desirable properties. Nevertheless, the analgesic and amnesic features of DEX are still questionable.

Dexmedetomidine as an adjuvant to local anesthetics in brachial plexus blocks: A meta-analysis of randomized controlled trials

BACKGROUND

Brachial plexus block (BPB) for upper extremity surgery provides superior analgesia, but this advantage is limited by the pharmacological duration of local anesthetics. Dexmedetomidine (DEX) as a local anesthetics adjuvant for BPB has been utilized to prolong the duration of the nerve block in some randomized controlled trials (RCTs) but is far from unanimous in the efficacy and safety of the perineural route. Hence, an updated meta-analysis was conducted to assess the efficacy and safety of DEX as local anesthetic adjuvants on BPB.

METHODS

A search in electronic databases was conducted to collect the RCTs that investigated the impact of adding DEX to local anesthetics for BPB. Sensory block duration, motor block duration, onset time of sensory and motor block, time to first analgesic request, the common adverse effects were analyzed.

RESULTS

Eighteen trails (1014 patients) were included with 515 patients receiving perineural DEX. The addition of DEX prolonged the duration of sensory block (WMD 257 minutes, 95%CI 191.79-322.24, P < 0.001), motor block (WMD 242 minutes, 95%CI 174.94-309.34, P < 0.001), and analgesia (WMD 26 6 minutes, 95%CI 190.75-342.81, P < 0.001). Perineural DEX also increased the risk of bradycardia (OR=8.25, 95%CI 3.95-17.24, P < 0.001), hypotension (OR = 5.62, 95%CI 1.52-20.79, P < 0.01), and somnolence (OR = 19.67, 95%CI 3.94-98.09, P < 0.001). There was a lack of evidence that perineural DEX increased the risk of other adverse events.

CONCLUSIONS

DEX is a potential anesthetic adjuvant that can facilitate better anesthesia and analgesia when administered in BPB. However, it also increased the risk of bradycardia, hypotension, and somnolence. Further research should focus on the efficacy and safety of the preneural administration of DEX.

To Evaluate the Efficacy of Fentanyl and Dexmedetomidine as Adjuvant to Ropivacaine in Brachial Plexus Block: A Double-blind, Prospective, Randomized Study

Context:

Anesthesia and analgesia for surgeries to the upper extremity are commonly provided using brachial plexus anesthesia. There are limited or almost no studies comparing the use of ropivacaine with fentanyl to ropivacaine with dexmedetomidine.

Aims:

To compare the efficacy of fentanyl and dexmedetomidine as adjuvants to ropivacaine for brachial plexus block among patients undergoing upper limb orthopedic surgeries.

Settings and Design:

This was a prospective, randomized, double-blinded study.

Subjects and Methods:

The patients were randomly divided into three groups of 35 each using computerized randomization table. Group I patients received 3 mg/kg of 0.75% ropivacaine with 1 μg/kg of fentanyl diluted with normal saline (NS) to make a total volume of 35 ml. Group II patients received 3 mg/kg of 0.75% ropivacaine with 1 μg/kg of dexmedetomidine diluted with NS to make a total volume of 35 ml. Group III patients received 3 mg/kg of 0.75% ropivacaine with NS making a total volume of 35 ml.

Statistical Analysis Used:

Statistical analysis was performed using Statistical Package for Social Sciences, version 15.0. Analysis of variance followed by independent samples t-test was performed for parametric data, and Kruskal–Wallis test followed by Mann–Whitney U-test was performed for nonparametric data.

Results:

Mean motor and sensory block onset time was minimum in Group I and maximum in Group III while mean duration of sensory and motor block was maximum in Group I and minimum in Group III. Time taken for first rescue analgesic dose was also maximum in Group I and minimum in Group III.

Conclusions:

It can be concluded that 3 mg/kg of 0.75% ropivacaine along with 1 μg/kg of fentanyl diluted with NS to make a total volume of 35 ml was the most efficacious regimen for brachial plexus block among patients undergoing upper limb orthopedic surgeries.

IV and Perineural Dexmedetomidine Similarly Prolong the Duration of Analgesia after Interscalene Brachial Plexus Block

Background

Perineural and IV dexmedetomidine have each been suggested to prolong the duration of analgesia when administered in conjunction with peripheral nerve blocks. In the first randomized, triple-masked, placebo-controlled trial to date, the authors aimed to define and compare the efficacy of perineural and IV dexmedetomidine in prolonging the analgesic duration of single-injection interscalene brachial plexus block (ISB) for outpatient shoulder surgery.

Methods

Ninety-nine patients were randomized to receive ISB using 15 ml ropivacaine, 0.5%, with 0.5 μg/kg dexmedetomidine administered perineurally (DexP group), intravenously (DexIV group), or none (control group). The authors sequentially tested the joint hypothesis that dexmedetomidine prolongs the duration of analgesia and reduces the 24-h cumulative postoperative morphine consumption. Motor blockade, pain severity, hemodynamic variations, opioid-related side effects, postoperative neurologic symptoms, and patient satisfaction were also evaluated.

Results

Ninety-nine patients were analyzed. The duration of analgesia was 10.9 h (10.0 to 11.8 h) and 9.8 h (9.0 to 10.6 h) for the DexP and DexIV groups, respectively, compared with 6.7 h (5.6 to 7.8) for the control group (P &lt; 0.001). Dexmedetomidine also reduced the 24-h cumulative morphine consumption to 63.9 mg (58.8 to 69.0 mg) and 66.2 mg (60.6 to 71.8 mg) for the DexP and DexIV groups, respectively, compared with 81.9 mg (75.0 to 88.9 mg) for the control group (P &lt; 0.001). DexIV was noninferior to DexP for these outcomes. Both dexmedetomidine routes reduced the pain and opioid consumption up to 8 h postoperatively and did not prolong the duration of motor blockade.

Conclusion

Both perineural and IV dexmedetomidine can effectively prolong the ISB analgesic duration and reduce the opioid consumption without prolonging motor blockade.