Improvement in postoperative pain control by combined use of intravenous dexamethasone with intravenous dexmedetomidine after interscalene brachial plexus block for arthroscopic shoulder surgery: A randomised controlled trial

Primary outcomes and anticipated effect sizes in randomised clinical trials assessing adjuncts to peripheral nerve blocks: A scoping review

BACKGROUND

Prolonging effects of adjuncts to local anaesthetics in peripheral nerve blocks have been demonstrated in randomised clinical trials. The chosen primary outcome and anticipated effect size have major impact on the clinical relevance of results in these trials. This scoping review aims to provide an overview of frequently used outcomes and anticipated effect sizes in randomised trials on peripheral nerve block adjuncts.

METHODS

For our scoping review, we searched MEDLINE, Embase and CENTRAL for trials assessing effects of adjuncts for peripheral nerve blocks published in 10 major anaesthesia journals. We included randomised clinical trials assessing adjuncts for single-shot ultrasound-guided peripheral nerve blocks, regardless of the type of interventional adjunct and control group, local anaesthetic used and anatomical localization. Our primary outcome was the choice of primary outcomes and corresponding anticipated effect size used for sample size estimation. Secondary outcomes were assessor of primary outcomes, the reporting of sample size calculations and statistically significant and non-significant results related to the anticipated effect sizes.

RESULTS

Of 11,854 screened trials, we included 59. The most frequent primary outcome was duration of analgesia (35/59 trials, 59%) with absolute and relative median (interquartile range) anticipated effect sizes for adjunct versus placebo/no adjunct: 240 min (180-318) and 30% (25-40) and for adjunct versus active comparator: 210 min (180-308) and 17% (15-28). Adequate sample size calculations were reported in 78% of trials. Statistically significant results were reported for primary outcomes in 45/59 trials (76%), of which 22% did not reach the anticipated effect size.

CONCLUSION

The reported outcomes and associated anticipated effect sizes can be used in future trials on adjuncts for peripheral nerve blocks to increase methodological homogeneity.

Combination of different local anesthetic adjunct for supraclavicular brachial plexus block after arthroscopic shoulder surgery: a prospective randomized controlled trial

BACKGROUND

Acute pain is a major concern after arthroscopic shoulder surgery, supraclavicular brachial plexus blockade has shown favorable postoperative analgesic effects. However, its duration of analgesia does not meet clinical needs. We aimed to explore whether the combination of different local anesthetic adjunct can prolong the analgesic duration of supraclavicular brachial plexus block for arthroscopic shoulder surgery.

METHODS

In this prospective randomized controlled trial, we allocated 80 patients into four groups: Group DMD (dexamethasone 10 mg + ropivacaine 100 mg + dexmedetomidine 50 µg + magnesium sulfate 250 mg), Group DM (ropivacaine 100 mg + dexmedetomidine 50 µg + magnesium sulfate 250 mg), Group M (ropivacaine 100 mg + magnesium sulfate 250 mg) and Group D (ropivacaine 100 mg + dexmedetomidine 50 µg). The primary outcome was the time to first request for analgesia. Secondary outcome measures included cumulative opioid consumption at 6, 12, 18, 24, and 48 h postoperatively, VAS scores at 6, 12, 18, 24, and 48 h postoperatively and so on.

RESULTS

The time to first request for analgesia in Group DMD was significantly longer than Group DM (P = 0.011) and Group M (P = 0.003). The cumulative opioid consumption at 18 h postoperatively in Group DMD was significantly lower than in Group DM (P = 0.002) and Group M (P = 0.007). The cumulative opioid consumption at 24 h postoperatively in Group DMD was significantly lower than in Group DM (P = 0.016). The VAS score at 6 h postoperatively in Group DMD was significantly lower than in Group DM and Group M. The VAS score at 12 h postoperatively in Group DMD was significantly lower than in Group M. For American Shoulder and Elbow Surgeons Score, Group DMD had a better score than Group DM and Group D.

CONCLUSIONS

The analgesic efficacy of supraclavicular brachial plexus blockade combined with dexamethasone, magnesium sulfate, and dexmedetomidine is significantly superior to the combination of magnesium sulfate and dexmedetomidine, and significantly superior to the use of magnesium sulfate alone.

TRIAL REGISTRATION

This trial was registered in Chinese Clinical Trial Registry. (ChiCTR2200061181, Date of registration: June 15, 2022, http://www.chictr.org.cn ).

Dexmedetomidine and Dexamethasone as Adjuvants to the Local Anesthetic Mixture in Rhomboid Intercostal and Sub-Serratus Block for Video-Assisted Thoracoscopic Surgery: A Randomized, Double-Blind, Controlled Trial

Background

The utilization of adjuvants such as dexamethasone and dexmedetomidine in combination with local anesthetics has proven effective in extending analgesia duration. We aimed to investigate the potential efficacy of combining dexmedetomidine and dexamethasone in rhomboid intercostal and sub-serratus (RISS) block for prolonging postoperative analgesia in patients undergoing video-assisted thoracoscopic surgery (VATS).

Methods

We did this randomized, double-blind, controlled trial in two tertiary-care hospitals. A total of eighty-eight patients undergoing VATS under general anesthesia were enrolled in this study. They were randomly assigned into four groups: ropivacaine (R) group, ropivacaine + dexmedetomidine (RM) group, ropivacaine + dexamethasone (RS) group, or ropivacaine + dexmedetomidine + dexamethasone (RSM) group. The primary outcome measure was the duration of analgesia. Secondary outcomes included Numeric Rating Scale (NRS) scores, cumulative oxycodone consumption, and adverse effects.

Results

The RSM group exhibited a significantly prolonged duration of analgesia at 1073.5 min (932.0-1283.3) compared to the R group with a duration of 154.5 min (80.5-199.3) and the RS group with a duration of 282.0 min (195.3-350.0, P < 0 0.001). The cumulative oxycodone consumption during the 0-12 hours and 0-24-hours period was significantly reduced in the RSM group compared to the R group (P < 0.05). There was also a lower incidence of nausea at 48 hours postoperatively in the RSM group compared to the RM group. However, there were no significant differences between the four groups regarding NRS pain scores.

Conclusion

The combination of ropivacaine, dexmedetomidine, and dexamethasone in RISS block significantly prolongs the duration of postoperative analgesia following VATS.

Impact of Intraoperative Dexamethasone on Perioperative Blood Glucose Levels: Systematic Review and Meta-Analysis of Randomized Trials

BACKGROUND

Dexamethasone is associated with increased blood glucose levels that could impact patient outcomes or management. This study aimed to synthesize the available evidence regarding the impact of an intraoperative single dose of dexamethasone on blood glucose levels.

METHODS

We searched CENTRAL, MEDLINE, and clinicaltrials.gov for randomized controlled trials (RCTs) comparing a single intraoperative dose of dexamethasone to control in adult patients who underwent noncardiac surgery. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the review was registered in PROSPERO (CRD42023420562). Data were pooled using a random-effects model. We reported pooled dichotomous data using odds ratios (OR) and continuous data using the mean difference (MD), reporting 95% confidence intervals (95% CIs), and corresponding P-values for both. Confidence in the evidence was appraised using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. As primary outcomes we assessed maximum blood glucose levels measurement and variation from baseline within 24 hours of surgery; blood glucose levels measurement and variation from baseline at 2, 4, 8, 12, and 24 hours after dexamethasone administration. As secondary outcomes, we evaluated insulin requirements and hyperglycemic events.

RESULTS

We included 23 RCTs, enrolling 11,154 participants overall. Dexamethasone was associated with a significant increment in blood glucose levels compared to control at all timepoints. The results showed an increase compared to control of 0.37 mmol L-1 (6.7 mg dL-1) at 2 hours (95% CI, 0.16-0.58 mmol L-1 or 2.9-10.5 mg dL-1), 0.97 mmol L-1 (17.5 mg dL-1) at 4 hours (95% CI, 0.67-1.25 mmol L-1 or 12.1-22.5 mg dL-1), 0.96 mmol L-1 (17.3 mg dL-1) at 8 hours (95% CI, 0.55-1.36 mmol L-1 or 9.9-24.5 mg dL-1), 0.90 mmol L-1 (16.2 mg dL-1) at 12 hours (95% CI, 0.62-1.19 mmol L-1 or 11.2-21.4 mg dL-1) and 0.59 mmol L-1 (10.6 mg dL-1) at 24 hours (95% CI, 0.22-0.96 mmol L-1 or 4.0-17.3 mg dL-1). No difference was found between subgroups regarding diabetic status (patients with diabetes versus patients without diabetes) in all the outcomes except 2 (maximum blood glucose levels variation within 24 hours and variation at 4 hours) and dexamethasone dose (4-5 mg vs 8-10 mg) in all the outcomes except 2 (blood glucose levels at 24 hours and hyperglycemic events).

CONCLUSIONS

Mean blood glucose levels rise between 0.37 and 1.63 mmol L-1 (6.7 and 29.4 mg dL-1) within 24 hours after a single dose of dexamethasone administered at induction of anesthesia compared to control, but in most patients this difference will not be clinically relevant.

Combined Dexamethasone and Dexmedetomidine as Adjuncts to Popliteal and Saphenous Nerve Blocks in Patients Undergoing Surgery of the Foot or Ankle: A Randomized, Blinded, Placebo-controlled Clinical Trial

BACKGROUND

Both dexamethasone and dexmedetomidine increase the duration of analgesia of peripheral nerve blocks. The authors hypothesized that combined intravenous dexamethasone and intravenous dexmedetomidine would result in a greater duration of analgesia when compared with intravenous dexamethasone alone and placebo.

METHODS

The authors randomly allocated participants undergoing surgery of the foot or ankle under general anesthesia and with a combined popliteal (sciatic) and saphenous nerve block to a combination of 12 mg dexamethasone and 1 µg/kg dexmedetomidine, 12 mg dexamethasone, or placebo (saline). The primary outcome was the duration of analgesia measured as the time from block performance until the first sensation of pain in the surgical area as reported by the participant. The authors predefined a 33% difference in the duration of analgesia as clinically relevant.

RESULTS

A total of 120 participants from two centers were randomized and 119 analyzed for the primary outcome. The median [interquartile range] duration of analgesia was 1,572 min [1,259 to 1,715] with combined dexamethasone and dexmedetomidine, 1,400 min [1,133 to 1,750] with dexamethasone alone, and 870 min [748 to 1,138] with placebo. Compared with placebo, the duration was greater with combined dexamethasone and dexmedetomidine (difference, 564 min; 98.33% CI, 301 to 794; P < 0.001) and with dexamethasone (difference, 489 min; 98.33% CI, 265 to 706; P < 0.001). The prolongations exceeded the authors' predefined clinically relevant difference. The duration was similar when combined dexamethasone and dexmedetomidine was compared with dexamethasone alone (difference, 61 min; 98.33% CI, -222 to 331; P = 0.614).

CONCLUSIONS

Dexamethasone with or without dexmedetomidine increased the duration of analgesia in patients undergoing surgery of the foot or ankle with a popliteal (sciatic) and saphenous nerve block. Combined dexamethasone and dexmedetomidine did not increase the duration of analgesia when compared with dexamethasone.

EDITOR’S PERSPECTIVE

Continuous Superior Trunk Block versus Single-Shot Superior Trunk Block with Intravenous Dexmedetomidine for Postoperative Analgesia in Arthroscopic Shoulder Surgery: A Prospective Randomized Controlled Trial

Background/Objectives: Intravenous dexmedetomidine (DEX) can increase the analgesia duration of peripheral nerve block; however, its effect in combination with superior trunk block (STB) remains unclear. We examined whether combining single-shot STB (SSTB) with intravenous DEX would provide noninferior postoperative analgesia comparable to that provided by continuous STB (CSTB). Methods: Ninety-two patients scheduled for elective arthroscopic rotator cuff repair were enrolled in this prospective randomized trial. Patients were randomly assigned to the CSTB or SSTB + DEX group. Postoperatively, each CSTB group patient received 15 mL of 0.5% ropivacaine and a continuous 0.2% ropivacaine infusion. Each SSTB group patient received a 15 mL postoperative bolus injection of 0.5% ropivacaine. DEX was administered at 2 mcg/kg for 30 min post anesthesia, then maintained at 0.5 mcg/kg/h till surgery ended. Pain scores were investigated every 12 h for 48 h post operation, with evaluation of rebound pain incidence and opioid consumption. Results: The SSTB + DEX group had significantly higher median pain scores at 12 h post operation (resting pain, 8.0 vs. 3.0; movement pain, 8.0 vs. 5.0) and a higher incidence of rebound pain (56% vs. 20%) than the CSTB group. However, no significant between-group differences were observed in pain scores postoperatively at 24, 36, or 48 h. The CSTB group required less opioids and fewer rescue analgesics within 12-24 h post operation than the SSTB + DEX group. Conclusions: Compared with CSTB, SSTB + DEX required additional adjuvant or multimodal analgesics to reduce the risk and intensity of postoperative rebound pain in patients who underwent arthroscopic rotator cuff repair.

Effects of combined dexamethasone and dexmedetomidine as adjuncts to peripheral nerve blocks: a systematic review with meta-analysis and trial sequential analysis

BACKGROUND/IMPORTANCE

The effects of combining dexamethasone and dexmedetomidine on block duration are unclear.

OBJECTIVE

To investigate the effects of combining dexamethasone and dexmedetomidine on block duration.

EVIDENCE REVIEW

Systematic review of randomized controlled trials (RCTs) from Medline, Embase, CENTRAL, CINAHL, the Web of Science, and BIOSIS until June 8, 2023. RCTs with adults undergoing surgery with a peripheral nerve block randomized to combined dexamethasone and dexmedetomidine versus placebo or other adjuncts were eligible. Primary outcome was duration of analgesia. We performed meta-analysis, trial sequential analysis, risk of bias-2, and Grading Recommendations Assessment, Development, and Evaluation assessment.

FINDINGS

We included 9 RCTs with 14 eligible comparisons. The combination of dexamethasone and dexmedetomidine was compared with placebo in three RCTs (173 participants), dexamethasone in seven (569 participants), and dexmedetomidine in four (281 participants). The duration of analgesia was likely increased with the combination versus placebo (mean difference 460 min, 95% CI 249 to 671) and versus dexmedetomidine (mean difference 388 min, 95% CI 211 to 565). The duration was likely similar with the combination versus dexamethasone (mean difference 50 min, 95% CI -140 to 239). The certainty of the evidence was moderate because most trials were at high risk of bias.

CONCLUSIONS

Combined dexamethasone and dexmedetomidine likely increased the duration of analgesia when compared with placebo and dexmedetomidine. The combination likely provided a similar duration of analgesia as dexamethasone. Based on this systematic review, it seems reasonable to use dexamethasone as the sole adjunct if the goal is to increase the duration of analgesia.

Efficacy of Infraclavicular Brachial Plexus Block Alone Versus Combination With Suprascapular Nerve Block in Patients Undergoing Shoulder Surgeries: A Single-Blind, Randomized Trial

Background and aim The regional anesthesia technique is commonly used for upper extremity surgery as an alternative to general anesthesia. The study aimed to compare the efficacy of infraclavicular brachial plexus block (BPB) and a combination of infraclavicular brachial plexus block with suprascapular nerve block for postoperative analgesia in patients undergoing shoulder surgeries. Method A total of 62 patients of both sexes with the American Society of Anaesthesiologists (ASA) physical status I/II/III, aged between 18 and 65 years, and undergoing shoulder surgery, were included in this prospective, single-blinded, randomized controlled trial. Patients were equally allocated into two groups: 31 in group A and 31 in group B. After pre-anesthetic evaluation, the purpose and protocol of the study were explained to patients, and informed consent was obtained. Thirty-one patients in group A were given infraclavicular brachial plexus block using 30 ml 0.375% bupivacaine while 31 patients in group B were given a combination of infraclavicular brachial plexus block using 30 ml 0.375% bupivacaine and suprascapular nerve block using 5 ml 0.375% bupivacaine. Blocks were given using ultrasound guidance and a peripheral nerve stimulator; the suprascapular block was given in the sitting position while the infraclavicular block was provided in the supine position. General anesthesia was administered in the operation theatre in the supine position after the administration of blocks. The pain was assessed using the visual analog scale (VAS) and the satisfaction score was assessed by the numeric rating scale (NRS). The Mann-Whitney U test was applied for comparison of pain between the two groups. The chi-square test was utilized for comparing the categorical variables. Result The postoperative pain was significantly lower (p<0.001) in group B as compared to group A at all the periods of observation, i.e., 0h (2.77±0.72 vs. 5.42±0.77), 6h (3.89±0.70 vs. 5.94±0.73), 12h (5.66±0.93 vs. 6.58±0.88), and 24h (6.16±0.80 vs. 6.74±0.90). These findings illustrate that group B patients who received a combination of infraclavicular brachial plexus block and suprascapular nerve block for shoulder surgeries had better pain relief than group A patients who received only the infraclavicular approach. The mean NRS score of patient satisfaction in group B (7.26±0.58) was significantly higher (p<0.001) in comparison to group A (6.16±0.64). Diaphragmatic palsy was observed in only one case in group A and none in group B. No other complication was observed in any of the patients during the study period. Conclusion The combination of infraclavicular brachial plexus block and suprascapular nerve block displays a positive postoperative analgesic profile with less usage of rescue analgesic doses and better patient satisfaction after shoulder surgery.

Comparison of dexmedetomidine and dexamethasone as adjuvants to the ultrasound-guided interscalene nerve block in arthroscopic shoulder surgery: a systematic review and Bayesian network meta-analysis of randomized controlled trials

Introduction

Interscalene block (ISB) is widely regarded as the gold standard treatment for acute pain following arthroscopic shoulder surgery. However, a single injection of a local anesthetic for ISB may not offer sufficient analgesia. Various adjuvants have been demonstrated to prolong the analgesic duration of the block. Hence, this study aimed to assess the relative efficacy of dexamethasone and dexmedetomidine as adjuncts to prolong the analgesic duration for a single- shot ISB.

Methods

The efficacy of adjuvants was compared using a network meta-analysis. The methodological quality of the included studies was evaluated using the Cochrane bias risk assessment tool. A comprehensive search of the PubMed, Cochrane, Web of Science, and Embase databases was conducted with a search deadline of March 1, 2023. Various adjuvant prevention randomized controlled trials have been conducted in patients undergoing interscalene brachial plexus block for shoulder arthroscopic surgery.

Results

Twenty-five studies enrolling a total of 2,194 patients reported duration of analgesia. Combined dexmedetomidine and dexamethasone (MD = 22.13, 95% CI 16.67, 27.58), dexamethasone administered perineurally (MD = 9.94, 95% CI 7.71, 12.17), high-dose intravenous dexamethasone (MD = 7.47, 95% CI 4.41, 10.53), dexmedetomidine administered perineurally (MD = 6.82, 95% CI 3.43, 10.20), and low-dose intravenous dexamethasone (MD = 6.72, 95% CI 3.74, 9.70) provided significantly longer analgesic effects compared with the control group.

Discussion

The combination of intravenous dexamethasone and dexmedetomidine provided the greatest effect in terms of prolonged analgesia, reduced opioid doses, and lower pain scores. Furthermore, peripheral dexamethasone in prolonging the analgesic duration and lowering opioid usage was better than the other adjuvants when used a single medication. All therapies significantly prolonged the analgesic duration and reduced the opioid dose of a single-shot ISB in shoulder arthroscopy compared with the placebo.

A randomised controlled trial of intravenous dexmedetomidine added to dexamethasone for arthroscopic rotator cuff repair and duration of interscalene block

Prolongation of peripheral nerve blockade by intravenous dexamethasone may be extended by intravenous dexmedetomidine. We randomly allocated 122 participants who had intravenous dexamethasone 0.15 mg.kg^-1 before interscalene brachial plexus block for day-case arthroscopic rotator cuff repair to intravenous saline (62 participants) or intravenous dexmedetomidine 1 μg.kg^-1 (60 participants). The primary outcome was time from block to first oral morphine intake during the first 48 postoperative hours. Fifty-nine participants reported taking oral morphine, 25/62 after placebo and 34/60 after dexmedetomidine, p = 0.10. The time to morphine intake was shorter after dexmedetomidine, hazard ratio (95%CI) 1.68 (1.00-2.82), p = 0.049. Median (IQR [range]) morphine doses were 0 (0-12.5 [0-50]) mg after control vs. 10 (0-30 [0-50]) after dexmedetomidine, a difference (95%CI) of 7 (0-10) mg, p = 0.056. There was no effect of dexmedetomidine on pain at rest or on movement. Intra-operative hypotension was recorded for 27/62 and 50/60 participants after placebo vs. dexmedetomidine, respectively, p < 0.001. Other outcomes were similar, including durations of sensory and motor block. In conclusion, dexmedetomidine shortened the time to oral morphine consumption after interscalene block combined with dexamethasone and caused intra-operative hypotension.

Measures to prolong duration of sensory block after regional anaesthesia

PURPOSE OF REVIEW

The duration of single-injection regional anaesthesia is limited due to the inherent pharmacological properties of local anaesthetics. The ideal duration of a regional anaesthesia block lasting for the first 24 h postoperatively can be stated, while a residual analgesic effect thereafter is desirable.The aim of this review is to present current options to prolong the duration of action of single-injection peripheral regional anaesthesia in the ambulatory setting. Secondly, this review outlines and discusses the latest evidence regarding the clinical use of adjuvants and sustained-release local anaesthetics.

RECENT FINDINGS

Extended-release formulations of local anaesthetics such as liposomal bupivacaine have been developed to prolong regional anaesthesia up to 96 h. Recent studies, however, show that the actual effects remain far behind expectations and that the efficacy is only marginally better than bupivacaine hydrochloride.Adjuvants to local anaesthetics have been studied extensively with heterogenous results. Dexamethasone and alpha-2 agonists range among the most effective measures to prolong single-injection nerve blocks.Continuous nerve blocks and catheter techniques may prolong regional anaesthesia very effectively, but are less cost-effective regarding block procedure, postoperative care and handling logistical issues especially in ambulatory surgery.

SUMMARY

In conclusion, adjuvants are the recommended measure to prolong regional anaesthesia where needed. With good evidence supporting it, dexamethasone is the most effective adjuvant, followed by dexmedetomidine. Both have few side effects and a favourable safety profile. However, a preferable duration of analgesia lasting for the first 24 h postoperatively is still not reliably achievable.

Postoperative neurologic symptoms in the operative arm after shoulder surgery with interscalene blockade: a systematic review

OBJECTIVE

Postoperative neurologic symptoms (PONS) in the operative arm are important complications of shoulder surgery and interscalene blockade (ISB). This systematic review aimed to compare the risk of PONS between ISB and other techniques, and the relative safety of different agents used in ISB.

METHODS

Our systematic review followed Cochrane review methodology and was registered in PROSPERO. A search of MEDLINE (Ovid), EMBASE (Ovid), and CENTRAL (Wiley) from inception to June 2020 was completed. We included randomized or quasi-randomized trials of patients (> five years old) undergoing shoulder surgery with any ISB technique as an intervention, compared with any other nonregional or regional technique, or ISB of alternate composition or technique. The primary outcome was PONS (study author defined) assessed a minimum of one week after surgery.

RESULTS

Fifty-five studies totalling 6,236 participants (median, 69; range, 30-910) were included. Another 422 otherwise eligible trials were excluded because PONS was not reported. Heterogeneity in when PONS was assessed (from one week to one year) and the diagnostic criteria used precluded quantitative meta-analysis. The most common PONS definition, consisting of one or more of paresthesia, sensory deficit, or motor deficit, was only used in 16/55 (29%) trials. Risk of bias was low in 5/55 (9%) trials and high in 36/55 (65%) trials, further limiting any inferences.

CONCLUSION

These findings highlight the need for a standardized PONS outcome definition and follow-up time, along with routine, rigorous measurement of PONS in trials of ISB.

STUDY REGISTRATION

PROSPERO (CRD42020148496); registered 10 February 2020.

Comparison of the effects of perineural or intravenous dexamethasone on thoracic paravertebral block in Ivor‐Lewis esophagectomy: A double‐blind randomized trial

Efforts to prolong thoracic paravertebral block (TPVB) analgesia include local anesthetic adjuvants, such as dexamethasone (Dex). Previous studies showed that both perineural (PN) and intravenous (i.v.) routes could prolong analgesia. As PN Dex is an off‐label use, anesthesiologists should be fully informed of the clinical differences, if any, on block duration. This study was designed to evaluate the two administration routes of Dex for duration of analgesia in TPVB. Ninety‐five patients scheduled for Ivor‐Lewis esophagectomy were randomized to receive TPVB (0.5% ropivacaine 15 ml), PN or i.v. Dex 8 mg. The primary end point was the duration of analgesia. The secondary end points included pain scores, analgesic consumption, adverse effects rate, and incidence of chronic pain at 3 months postoperatively. The PN‐Dex group showed better analgesic effects than the i.v.‐Dex group (p < 0.05). Similarly, the visual analogue scale scores in patients at 2, 4, 8, and 12 h postoperatively were lower in the PN‐Dex group than the i.v.‐Dex group (p < 0.05). The analgesic consumption in both the PN‐Dex and i.v.‐Dex groups was significantly lower than that in the control group (p < 0.05). Regarding the incidence of chronic pain, regardless of route, Dex decreased the incidence of chronic postsurgical pain and neuropathic pain at 3 months after surgery (p < 0.05), but there were no clinical differences between the i.v.‐Dex and PN‐Dex groups. Perineural dexamethasone improved the magnitude and duration of analgesia compared to that of the i.v.‐Dex group in TPVB in Ivor‐Lewis esophagectomy. However, there were no clinically significant differences between the two groups in the incidence of chronic pain.

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.

The Effect of Intravenous Dexamethasone and Dexmedetomidine on Analgesia Duration of Supraclavicular Brachial Plexus Block: A Randomized, Four-Arm, Triple-Blinded, Placebo-Controlled Trial

Intravenous dexamethasone and dexmedetomidine, in conjunction with peripheral nerve blockade, have each been reported to prolong the duration of analgesia. This study tested whether combined use further prolongs analgesia duration after supraclavicular brachial plexus block (BPB) in patients undergoing orthopedic upper extremity surgery. One hundred twenty patients were randomized 1:1:1:1 to Control (saline bolus and midazolam infusion [0.05 mg/kg loading, 20 µg/kg/h thereafter]); DMED (saline bolus and dexmedetomidine infusion [1 μg/kg loading, 0.4 μg/kg/h thereafter]); DEXA (dexamethasone [10 mg] bolus and midazolam infusion); and DMED-DEXA (dexmedetomidine infusion and dexamethasone bolus) groups. The primary outcome was the duration of postoperative analgesia, defined as the time from the end of the BPB to the first dose of analgesia via a patient-controlled device. Median (interquartile range) times to first dose of analgesia in the Control, DMED, DEXA, and DMED-DEXA groups were 8.1 (6.2–11.6), 9.0 (8.1–11.3), 10.7 (8.1–20.5), and 13.2 (11.5–19.1) hours, respectively (p < 0.001). Pairwise comparisons showed significant prolongation of analgesia in the DEXA included groups compared with the non-DEXA included groups (DEXA vs. control, p = 0.045; DEXA vs. DMED, p = 0.045; DMED-DEXA vs. control, p < 0.001; DMED-DEXA vs. DMED, p < 0.001). A mixed effect model showed that dexamethasone was the only significant factor for the prolongation of analgesia (p < 0.001). Intravenous dexamethasone prolonged the analgesia duration of supraclavicular BPB after orthopedic upper extremity surgery. The concurrent use of mild to moderate sedation dose of intravenous dexmedetomidine in addition to intravenous dexamethasone showed no additional benefit to the prolongation of analgesia.

Effect of Different Modes of Administration of Dexmedetomidine Combined with Nerve Block on Postoperative Analgesia in Total Knee Arthroplasty

INTRODUCTION

Dexmedetomidine (DEX) as a nerve block adjuvant can significantly prolong analgesia. However, whether perineural or systemic administration of DEX is more beneficial in patients undergoing total knee arthroplasty (TKA) has not been thoroughly investigated. To this end, we evaluated the effects of perineural and systemic DEX administration on postoperative analgesia in patients undergoing TKA surgery.

METHODS

We randomly assigned patients undergoing TKA under general anesthesia combined with femoral nerve block and sciatic nerve block to one of three groups: (1) ropivacaine plus perineural dexmedetomidine (DP): 0.25% ropivacaine 40 mL plus 0.5 μg/kg dexmedetomidine; (2) ropivacaine plus systemic dexmedetomidine (DS): 0.25% ropivacaine 40 mL plus systemic 0.5 μg/kg dexmedetomidine; (3) control group (C): 0.25% ropivacaine 40 mL.

RESULTS

The average length of time until patients first experienced postoperative pain was significantly longer in the DP group (26.0 h [22.0-30.0 h]) than in the DS group (22.4 h [18-26.8 h]) and the control group (22.9 h [19.5-26.3 h], P = 0.001). For this result there was no significant difference between the DS and the control group. Compared with the DS and control groups, patients in the DP group had lower resting visual analogue scale (VAS) scores at 24, 48, and 72 h after surgery (P < 0.05). VAS activity scores at 12, 24, and 48 h after surgery in the DP group were lower than those in the DS and control groups, with a statistically significant difference (P < 0.05). Compared with the DS and control groups, the amount of postoperative opioids in the DP group was also significantly reduced, and the number of people needing postoperative rescue analgesia was significantly lower, with a statistical difference (P < 0.05). Meanwhile, the sleep satisfaction of patients in the DP group on the first night after surgery and the satisfaction with pain control at 72 h after surgery were both higher than those in the DS group and control group (P < 0.05).

CONCLUSIONS

Perineural administration of DEX can significantly prolong the interval until patients report pain for the first time after TKA, relieve postoperative pain, reduce postoperative opioid dosage, and improve postoperative sleep quality and satisfaction with pain control.

TRIAL REGISTRATION

The trial was registered at the Chinese Clinical Trial Registry, identifier ChiCTR1900025808.

Comparison of continuous and single interscalene block for quality of recovery score following arthroscopic rotator cuff repair

BACKGROUND

Continuous interscalene brachial plexus block (CISB) is well known to reduce postoperative pain and to improve patient satisfaction. However, the effect of CISB on the quality of postoperative recovery is unknown. We Compared the quality of recovery from arthroscopic rotator cuff repair in patients who received CISB or single interscalene brachial plexus block (SISB).

METHODS

This prospective non-randomized controlled trial with propensity score matching enrolled 134 patients undergoing arthroscopic surgery for rotator cuff repair. Each patient received an interscalene block before surgery. One group had a catheter insertion 30 min after the end of surgery and started patient-controlled regional analgesia (PCRA, n = 49). The other group received intravenous patient-controlled analgesia (IV-PCA, n = 85). The primary outcome was the quality of recovery (QoR-40) score. Also, postoperative analgesia, sleep quality, and postoperative complications were evaluated.

RESULTS

The two groups had similar QoR-40 score on postoperative day-1 (POD1), but the PCRA group had a significantly greater QoR-40 score on POD2 (156.0, IQR: 143.0, 169.0 vs. 171.0, IQR: 159.0, 178.0; p < 0.001). The IV-PCA group received more analgesics during the 2 days after surgery, especially during night-time, and had a higher prevalence of sleep disturbances. The time to first additional analgesics request was significantly longer in PCRA group (14 hours, 95% CI: 13-16 vs. 44 hours, 95% CI: 28-not applicable). The incidence of postoperative nausea and vomiting significantly lower in the PCRA group (16.3% vs 46.9%, p = 0.002).

CONCLUSION

CISB showed a higher quality of recovery score than SISB with IV-PCA in arthroscopic rotator cuff repair, probably related to the effective analgesia, improved sleep quality, and reduced opioid-related complications.

Pain Control After Shoulder Arthroscopy: A Systematic Review of Randomized Controlled Trials With a Network Meta-analysis

BACKGROUND

Shoulder arthroscopy is one of the most commonly performed orthopaedic procedures used to treat a variety of conditions, with >500,000 procedures performed each year.

PURPOSE

To systematically review the randomized controlled trials (RCTs) on pain control after shoulder arthroscopy in the acute postoperative setting and to ascertain the best available evidence in managing pain after shoulder arthroscopy to optimize patient outcomes.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic review of the literature was performed based on the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines. Studies were included if they were RCTs evaluating interventions to reduce postoperative pain after shoulder arthroscopy: nerve blocks, nerve block adjuncts, subacromial injections, patient-controlled analgesia, oral medications, or other modalities. Meta-analyses and network meta-analyses were performed where appropriate.

RESULTS

Our study included 83 RCTs. Across 40 studies, peripheral nerve blocks were found to significantly reduce postoperative pain and opioid use, but there was no significant difference among the variable nerve blocks in the network meta-analysis. However, continuous interscalene block did have the highest P-score at most time points. Nerve block adjuncts were consistently shown across 18 studies to prolong the nerve block time and reduce pain. Preoperative administration was shown to significantly reduce postoperative pain scores (P < .05). No benefit was found in any of the studies evaluating subacromial infusions.

CONCLUSION

Continuous interscalene block resulted in the lowest pain levels at most time points, although this was not significantly different when compared with the other nerve blocks. Additionally, nerve block adjuncts may prolong the postoperative block time and improve pain control. There is promising evidence for some oral medications and newer modalities to control pain and reduce opioid use. However, we found no evidence to support the use of subacromial infusions or patient-controlled analgesia.

Analgesic duration of interscalene block after outpatient arthroscopic shoulder surgery with intravenous dexamethasone, intravenous dexmedetomidine, or their combination: a randomized-controlled trial

PURPOSE

Both intravenous dexamethasone and dexmedetomidine prolong the analgesic duration of interscalene blocks (ISB) after arthroscopic shoulder surgery. This study compared their relative effectiveness and the benefit of their use in combination.

METHODS

This single-centre, double-blinded, parallel three-group superiority trial randomized 198 adult patients undergoing ambulatory arthroscopic shoulder surgery. Patients received preoperative ISB with 30 mL 0.5% bupivacaine and 50 µg dexmedetomidine or 4 mg dexamethasone or both of these agents as intravenous adjuncts. The primary outcome was analgesic block duration. Secondary outcomes included the quality of recovery 15 score (range: 0-150) on day 1 and postoperative neurologic symptoms in the surgical arm.

RESULTS

Block durations (n = 195) with dexamethasone (median [range], 24.5 [2.0-339.5] hr) and both adjuncts (24.0 [1.5-157.0] hr) were prolonged compared with dexmedetomidine (16.0 [1.5-154.0] hr). When analyzed by linear regression after an unplanned log transformation because of right-skewed data, the corresponding prolongations of block duration were 59% (95% confidence interval [CI], 28 to 97) and 46% (95% CI, 18 to 80), respectively (both P < 0.001). The combined adjuncts were not superior to dexamethasone alone (-8%; 95% CI, -26 to 14; P = 0.42). Median [IQR] quality of recovery 15 scores (n = 197) were significantly different only between dexamethasone (126 [79-149]) and dexmedetomidine (118.5 [41-150], P = 0.004), but by an amount less than the 8-point minimum clinically important difference.

CONCLUSION

Dexamethasone is superior to dexmedetomidine as an intravenous adjunct for prolongation of bupivacaine-based ISB analgesic duration. There was no additional benefit to using both adjuncts in combination.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT03270033); registered 1 September 2017.

Efficacy of perineural versus intravenous dexmedetomidine as a peripheral nerve block adjunct: a systematic review

BACKGROUND

Dexmedetomidine is an effective local anesthetic adjunct for peripheral nerve blocks. The intravenous route for administering dexmedetomidine has been suggested to be equally effective to the perineural route; but comparative evidence is conflicting.

OBJECTIVES

This evidence-based review evaluated trials comparing the effects of intravenous to perineural dexmedetomidine on peripheral nerve block characteristics in adult surgical patients. Our primary aim was to evaluate the durations of sensory and motor blockade. Duration of analgesia, onset times of sensory and motor blockade, analgesic consumption, rest pain, and dexmedetomidine-related adverse events were evaluated as secondary outcomes.

EVIDENCE REVIEW

We sought randomized trials comparing the effects of intravenous to perineural dexmedetomidine on peripheral nerve block characteristics. The Cochrane Risk of Bias tool and the Grades of Recommendation, Assessment, Development, and Evaluation criteria was used to evaluate the quality of evidence for when an outcome was reported by at least three studies.

RESULTS

Ten studies compared intravenous and perineural dexmedetomidine in the setting of upper extremity blocks (seven), lower extremity blocks (two), and truncal block (one). The doses of dexmedetomidine supplementing long-acting local anesthetics varied between a predetermined dose (50 μg) and a weight-based dose (0.5 μg/kg-1.0 μg/kg). Clinical diversity precluded quantitative pooling; and evidence is presented as a systematic review. Compared with the intravenous route, moderate quality evidence found that perineural dexmedetomidine prolonged the duration of sensory blockade in four of six trials and motor blockade in five of seven trials. Perineural dexmedetomidine also hastened the onset of sensory and motor blockade in three of six trials. No differences were reported for the remaining outcomes; and intravenous dexmedetomidine was not superior for any outcome in any of the trials.

CONCLUSIONS

Moderate quality evidence appears to suggest that intravenous dexmedetomidine is an inferior peripheral nerve block adjunct compared with perineural dexmedetomidine. Perineural dexmedetomidine is associated with longer durations and faster onset of sensory and motor blockade.

A combination of infraclavicular and suprascapular nerve blocks for total shoulder arthroplasty: A case series

BACKGROUND

Shoulder arthroplasty is associated with significant post-operative pain. Interscalene plexus block is the gold standard for pain management in patients undergoing this surgery, however, alternatives are currently being developed. We hypothesized that a combination of anterior suprascapular nerve block and lateral sagittal infraclavicular block would provide effective post-operative analgesia. Primary aims for this study were to document numeric rating scale (NRS) pain score and use of oral morphine equivalents (OMEq) during the first 24 hours after surgery. Secondary aim was to determine the incidence of hemidiaphragmatic paralysis.

METHODS

Twenty patients (ASA physical status I-III) scheduled for shoulder arthroplasty were studied. Four mL ropivacaine 0.5% was administered for the suprascapular nerve block and 15 mL ropivacaine 0.75% for the infraclavicular block. Surgery was performed under general anaesthesia. Paracetamol and prolonged-release oxycodone were prescribed as post-operative analgesics. Morphine and oxycodone were prescribed as rescue pain medication. Diaphragm status was assessed by ultrasound.

RESULTS

Median NRS (0-10) at 1, 3, 6, 8 and 24 hours post-operatively were 1, 0, 0, 0 and 3, respectively. NRS at rest during the first 24 post-operative hours was 4 (2.5-4.5 [0-5]), median (IQR [range]). Maximum NRS was 6.5 (5-8 [0-10]) median (IQR [range]). Total OMEq during the first 24 post-operative hours was 52.5 mg (30-60 [26.4-121.5]) median (IQR [range]). Hemidiaphragmatic paralysis was diagnosed in one patient (5%).

CONCLUSIONS

The combination of suprascapular and infraclavicular nerve block shows an encouraging post-operative analgesic profile and a low risk for hemidiaphragmatic paralysis after total shoulder arthroplasty.

Evaluation of ropivacaine combined with dexmedetomidine versus ropivacaine alone for epidural anesthesia: A meta-analysis

BACKGROUND

Ropivacaine is considered the most commonly used for epidural anesthesia. We compared the efficiency and safety of ropivacaine alone (R group) and ropivacaine combined with dexmedetomidine (RD group).

METHOD

PubMed, the Cochrane Library, Google Scholar, Ovid Medline, the Web of Science, Scopus, Embase, and ScienceDirect were searched. We considered sensory and motor block, duration of anesthesia, time to rescue, hemodynamics, and adverse effects as the primary endpoints.

RESULTS

Eleven randomized controlled trials were included with 337 patients in the R group and 336 patients in the RD group. The RD group had a shorter time to onset of sensory (mean difference [MD]: 3.97 [1.90-6.04] minutes; P = .0002) and motor (MD: 2.43 [0.70-4.16] minutes; P = .006) block and a longer duration of anesthesia (MD: -164.17 [-294.43 to -33.91]; P = .01) than the R group. Comparison of the time to rescue between the groups showed no significant difference (MD: -119.01[-254.47-16.46] minutes; P = 0.09). The R group showed more stable hemodynamics than the RD group in heart rate and arterial pressure at 10 minutes. The R group had a lower incidence of bradycardia and a higher incidence of shivering than the RD group.

CONCLUSION

RD may be a more suitable choice for epidural anesthesia with better anesthetic outcomes than R alone. However, the safety of the combination must be carefully assessed.

Total knee arthroplasty under quadruple nerve block with ropivacaine 0.32%: effect of addition of intravenous dexmedetomidine to intravenous dexamethasone on analgesic duration

BACKGROUND AND OBJECTIVES

Peripheral nerve blocks reduce postoperative pain and enhance recovery after total knee arthroplasty (TKA). This study aims to assess the benefits of addition of intravenous dexmedetomidine (DexM) to intravenous dexamethasone on the analgesic duration of quadruple nerve blocks.

METHODS

This double-blind, randomized, controlled trial prospectively enrolled 90 patients scheduled for TKA under quadruple nerve blocks (sciatic, femoral, obturator, and lateral femoral cutaneous nerves blocks) with 70 mL, 0.32% ropivacaine. All patients received systemic dexamethasone 10 mg. Patients were randomized to receive DexM (2 µg/kg, intravenous) or placebo (1:1 ratio). The primary endpoint was the duration of analgesia defined as the time to first request for rescue analgesia (oxycodone).

RESULTS

Kaplan-Meier curves for the first analgesic request were similar between groups (log-rank test; p=0.27). Median (IQR) duration of analgesia was similar between placebo (1575 min (1211-1952)) and DexM (1470 min (1263-1700)) groups (p=0.56). Cumulative consumption of oxycodone at the 48th hour was 20 mg (10-30) and 30 mg (20-40) in placebo and DexM groups, respectively (p=0.14). The day after surgery, 93% and 89% of patients were able to walk in placebo and DexM groups, respectively (p=0.46). Intravenous DexM was associated with bradycardia, hypotension and longer recovery room stay (p<0.05 for all comparisons).

CONCLUSIONS

In a multimodal analgesic regimen, addition of systemic DexM (2 µg/kg) to systemic dexamethasone does not prolong the analgesic duration of quadruple nerve block with ropivacaine 0.32% after TKA.

TRIAL REGISTRATION NUMBER

NCT03834129.

Effect of Intraoperative Sedation with Dexmedetomidine Versus Propofol on Acute Postoperative Pain Following Major Foot Surgery under Popliteal Sciatic Nerve Block: A Randomized Controlled Trial

Intravenous (IV) dexmedetomidine is reported to prolong analgesia following peripheral nerve blocks. Popliteal sciatic nerve block provides effective postoperative analgesia, but some patients still experience severe pain during the early postoperative period. We aimed to evaluate the postoperative analgesic effects of IV dexmedetomidine versus propofol in patients undergoing foot surgeries under popliteal sciatic nerve block. Forty patients were enrolled and randomly assigned to receive either IV propofol (n = 20) or IV dexmedetomidine (n = 20) for intraoperative sedation. All the patients received continuous popliteal sciatic nerve block. The corresponding drug infusion rate was adjusted to achieve a modified observer’s assessment of alertness/sedation score of 3 or 4. The primary outcome was postoperative cumulative opioid consumption during the first 24 h after surgery. Thirty-nine patients were analyzed. The median (interquartile ranges) postoperative cumulative opioid consumption during the first 24 h after surgery was significantly lower in the dexmedetomidine group (15 (7.5–16.9) mg) than in the propofol group (17.5 (15–25) mg) (p = 0.019). The time to first rescue analgesic request was significantly greater in the dexmedetomidine group than in the propofol group (11.8 ± 2.2 h vs. 10.0 ± 2.7 h, p = 0.030) without the prolonged motor blockade (p = 0.321). Intraoperative sedation with dexmedetomidine reduced postoperative opioid consumption and prolonged analgesic duration after a popliteal sciatic nerve block.

Advances in regional anaesthesia and acute pain management: a narrative review

Regional anaesthesia has undergone several exciting advances in the past few decades. Ultrasound-guided techniques of peripheral nerve blockade have become the gold standard thanks to the associated improvements in efficacy, ease of performance and safety. This has increased the accessibility and utilisation of regional anaesthesia in the anaesthesia community at large and is timely given the mounting evidence for its potential benefits on various patient-centred outcomes, including major morbidity, cancer recurrence and persistent postoperative pain. Ultrasound guidance has also paved the way for refinement of the technical performance of existing blocks concerning simplicity and safety, as well as the development of new regional anaesthesia techniques. In particular, the emergence of fascial plane blocks has further broadened the application of regional anaesthesia in the management of painful conditions of the thorax and abdomen. The preliminary results of investigations into these fascial plane blocks are promising but require further research to establish their true value and role in clinical care. One of the challenges that remains is how best to prolong regional anaesthesia to maximise its benefits while avoiding undue harm. There is ongoing research into optimising continuous catheter techniques and their management, intravenous and perineural pharmacological adjuncts, and sustained-release local anaesthetic molecules. Finally, there is a growing appreciation for the critical role that regional anaesthesia can play in an overall multimodal anaesthetic strategy. This is especially pertinent given the current focus on eliminating unnecessary peri-operative opioid administration.

Superior Trunk Block Provides Noninferior Analgesia Compared with Interscalene Brachial Plexus Block in Arthroscopic Shoulder Surgery

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

Interscalene brachial plexus block of the C5–C6 roots provides highly effective postoperative analgesia after shoulder surgery but usually results in hemidiaphragmatic paresis. Injection around the superior trunk of the brachial plexus is an alternative technique that may reduce this risk. The authors hypothesized that the superior trunk block would provide noninferior postoperative analgesia compared with the interscalene block and reduce hemidiaphragmatic paresis.

Methods

Eighty patients undergoing arthroscopic shoulder surgery were randomized to receive a preoperative injection of 15 ml of 0.5% ropivacaine and 5 μg · ml−1 epinephrine around either (1) the C5–C6 nerve roots (interscalene block group) or (2) the superior trunk (superior trunk block group). The primary outcome was pain intensity 24 h after surgery measured on an 11-point numerical rating score; the prespecified noninferiority limit was 1. Diaphragmatic function was assessed using both ultrasonographic measurement of excursion and incentive spirometry by a blinded investigator before and 30 min after block completion.

Results

Seventy-eight patients completed the study. The pain score 24 h postoperatively (means ± SDs) was 1.4 ± 1.0 versus 1.2 ± 1.0 in the superior trunk block (n = 38) and interscalene block (n = 40) groups, respectively. The mean difference in pain scores was 0.1 (95% CI, −0.3 to 0.6), and the upper limit of the 95% CI was lower than the prespecified noninferiority limit. Analgesic requirements and all other pain measurements were similar between groups. Hemidiaphragmatic paresis was observed in 97.5% of the interscalene block group versus 76.3% of the superior trunk block group (P = 0.006); paresis was complete in 72.5% versus 5.3% of the patients, respectively. The decrease in spirometry values from baseline was significantly greater in the interscalene block group.

Conclusions

The superior trunk block provided noninferior analgesia compared with interscalene brachial plexus block for up to 24 h after arthroscopic shoulder surgery and resulted in significantly less hemidiaphragmatic paresis.

Bilateral single-injection erector spinae plane block versus intrathecal morphine for postoperative analgesia in living donor laparoscopic hepatectomy: a randomized non-inferiority trial

BACKGROUND

Intrathecal morphine (ITM) provides effective postoperative analgesia in living donor hepatectomy but has significant adverse effects. Studies support the efficacy of erector spinae plane (ESP) blocks in laparoscopic abdominal surgery; we therefore hypothesized that they would provide non-inferior postoperative analgesia compared with ITM and reduce postoperative nausea/vomiting and pruritus. We conducted a randomized, controlled, non-inferiority trial to compare the analgesic efficacy of ITM and bilateral single-injection ESP blocks in laparoscopic donor hepatectomy.

METHODS

Fifty-four donors were randomized to receive bilateral ESP blocks with 20 mL 0.5% ropivacaine (n=27) or 400 µg ITM (n=27). Primary outcome was resting pain score 24 hours postoperatively measured on an 11-point numeric rating scale. The prespecified non-inferiority limit was 1. Incidences of postoperative nausea/vomiting and pruritus were assessed.

RESULTS

The mean treatment difference (ESP-ITM) in the primary outcome was 1.2 (95% CI 0.7 to 1.8). The 95% CI upper limit exceeded the non-inferiority limit. Opioid consumption and all other pain measurements were similar between groups up to 72 hours postoperatively. The ESP group had significantly lower incidences of postoperative vomiting (p=0.002) and pruritus (p<0.001).

CONCLUSIONS

Bilateral single-injection ESP blocks resulted in higher resting pain scores 24 hours postoperatively compared with ITM and thus did not meet the study definition of non-inferiority. However, the pain intensity with ESP blocks was mild (mean pain scores <3/10) and associated with reduced incidence of postoperative vomiting and pruritus. It warrants further investigation as an analgesic option after laparoscopic living donor hepatectomy.

TRIAL REGISTRATION NUMBER

KCT0003191.