A Double-Blind Randomized Comparison of Continuous Interscalene, Supraclavicular, and Suprascapular Blocks for Total Shoulder Arthroplasty:

Anesthesia for the Patient Undergoing Shoulder Surgery

Shoulder surgery introduces important anesthesia considerations. The interscalene nerve block is considered the gold standard regional anesthetic technique and can serve as the primary anesthetic or can be used for postoperative analgesia. Phrenic nerve blockade is a limitation of the interscalene block and various phrenic-sparing strategies and techniques have been described. Patient positioning is another important anesthetic consideration and can be associated with significant hemodynamic effects and position-related injuries.

The efficacy of ultrasound-guided upper thoracic erector spinae plane block for postoperative analgesia in proximal shoulder surgery and its effect on phrenic nerve function: A prospective exploratory study

Background and Aims

The upper thoracic (T2) erector spinae plane block (UT-ESPB) has been proposed as an alternative to interscalene brachial plexus block for postoperative analgesia in shoulder surgery. The current study was conducted to evaluate the same.

Material and Methods

Patients scheduled for shoulder surgery under general anesthesia (GA) received ultrasound-guided UT-ESPB. The outcomes measured were diaphragmatic movements, block characteristics, and quality of recovery at 24 h.

Results

A total of 43 patients were recruited. The incidence of phrenic nerve palsy was 0%. The sensory level achieved by the maximum number of patients at the end of 30 min was C7-T5 level, and none had a motor block. Forty-two percent of patients did not require rescue analgesia till 24 h postoperative. In the rest of the patients, the mean (SD) duration of analgesia was 724.2 ± 486.80 min, and the mean postoperative requirement of fentanyl was 98.80 ± 47.02 μg. The median pain score (NRS) during rest and movement is 2 to 3 and 3 to 4, respectively. The median quality of recovery score at the end of 24 h after the block was 14 (15-14).

Conclusion

The upper thoracic ESPB resulted in a sensory loss from C7-T5 dermatomes without any weakness of the diaphragm and upper limb. However, the block was moderately effective in terms of the total duration of analgesia, postoperative pain scores, analgesic requirement, and quality of recovery in patients undergoing proximal shoulder surgeries under GA. Further studies are required to establish its role due to its poor correlation with sensory spread.

Comparison of the Analgesic Efficacy between Arthroscopically Placed Continuous Suprascapular Nerve Block and Ultrasound-guided Continuous Superior Trunk Block: A Double-blinded Randomized Controlled Trial

BACKGROUND

Single-shot suprascapular nerve block and superior trunk block have been reported to provide a noninferior analgesic effect after shoulder surgery with a lesser incidence of hemidiaphragmatic paresis compared with interscalene brachial plexus block. This study hypothesized that continuous suprascapular nerve block provides noninferior analgesia with minimal effects on diaphragmatic movement compared with continuous superior trunk block in patients undergoing arthroscopic shoulder surgery.

METHODS

100 patients were randomized undergoing arthroscopic shoulder surgery between December 2020 and October 2021 into continuous suprascapular nerve block and continuous superior trunk block groups. Before the surgery, patients received either a single-shot superior trunk block or subomohyoid suprascapular nerve block. Thereafter, a superior trunk catheter was inserted by anesthesiologists in patients in the continuous superior trunk block group, and a posterior suprascapular nerve catheter was inserted with arthroscopic assistance during the surgery by surgeon in the continuous suprascapular nerve block group. The primary outcome was the postoperative pain score at postoperative 24 h, and the incidence of hemidiaphragmatic paresis was also compared.

RESULTS

Overall, 98 patients were included in the final analysis. The worst and resting pain scores at postoperative 24 h in the continuous suprascapular nerve block group were inferior compared with those in the continuous superior trunk block group in the test with a noninferiority margin of 1 (worst pain score: mean difference, 0.9; 95% CI, 0.1 to 1.7; resting pain score: mean difference, 0.5; 95% CI, 0.0 to 1.0). However, the continuous suprascapular nerve block group had a significantly lower incidence of hemidiaphragmatic paresis at postoperative 24 h than the continuous superior trunk block group.

CONCLUSIONS

Continuous suprascapular nerve block provides statistically inferior analgesia compared to the continuous superior trunk block; however, the continuous suprascapular nerve block had a minimal effect on the phrenic nerve function.

EDITOR’S PERSPECTIVE

Evolution of Perioperative Pain Management in Shoulder Arthroplasty

Historically, opioids have been used as a primary conservative treatment for pain related to glenohumeral osteoarthritis (GHOA). However, this practice is concerning as it often leads to overuse, which has contributed to the current epidemic of addiction and overdoses in the United States. Studies have shown that preoperative opioid use is associated with higher complication rates and worse outcomes following surgery, particularly for shoulder arthroplasty. To address these concerns, perioperative pain management for shoulder arthroplasty has evolved over the years to the use of multimodal analgesia.

Liposomal bupivacaine nerve block provides better pain control post-total shoulder arthroplasty than continuous indwelling catheter

BACKGROUND

Pain control is essential to successful total shoulder arthroplasty (TSA).

MATERIALS AND METHODS

This non-blinded, randomized clinical trial compared shoulder pain, narcotic use, interscalene (IS) block application time, and costs in 76 subjects who were randomly assigned to receive either a single injection IS nerve block of 10 cc (133 mg) liposomal bupivacaine mixed with 10 cc of 0.5% bupivacaine (Group 1), or 20 cc of 0.5% ropivacaine direct injection combined with an indwelling IS nerve block catheter delivering 0.2% ropivacaine at a continual 4 cc/h infusion for the initial 3 post-operative days (Group 2). Surgical time, local anesthesia duration, hospital stay length, morphine milligram equivalents (MME) consumed, worst shoulder pain at 24, 48 and 72 h, and complications were recorded. Patient reported function, pain and activity level surveys were completed before, and 6-week post-TSA (P < 0.05).

RESULTS

Group 1 had less pain 24-h (0.72 ± 0.8 vs. 3.4 ± 2.9, p < 0.0001) and 48-h (2.5 ± 2.2 vs. 4.8 ± 2.6, p = 0.005) post-TSA. At 24-h post-TSA, MME consumption was similar (Group 1 = 4.5 ± 6.4 vs. Group 2 = 3.7 ± 3.8, p = 0.54), but was lower for Group 1 at 48 h (0.0 ± 0.0 vs. 0.64 ± 0.99, p = 0.001). Group 2 had longer IS block application time (10.00 ± 4.6 min vs. 4.84 ± 2.7 min, p < 0.0001). Only group 2 had a strong relationship between MME consumption over the first 24-h post-TSA and pain 24-h post-TSA (r = 0.76, p < 0.0001), a moderate relationship with pain 48-h post-TSA (r = 0.59, P = 0.001), and a weak relationship with pain 72-h post-TSA (r = 0.44, P = 0.02). Significant relationships for these variables were not observed for Group 1 (r ≤ 0.30, p ≥ 0.23). Group 1 IS block costs were less/patient than Group 2 ($190.17 vs. $357.12 USD).

CONCLUSION

A single shot, liposomal bupivacaine interscalene nerve block provided better post-TSA pain control with less narcotic consumption, less time for administration and less healthcare system cost compared to interscalene nerve block using a continuous indwelling catheter.

LEVEL OF EVIDENCE

Level I, Prospective, Randomized.

Single injection combined suprascapular and axillary nerve block: A randomised controlled non-inferiority trial in healthy volunteers

BACKGROUND

A shoulder block without lung affection is desirable. In this study, we compared a low versus a high volume of a modified supraclavicular brachial plexus block. We hypothesised that a low volume of local anaesthetic would provide non-inferior block success rate with better preserved lung function.

METHODS

Healthy volunteers were randomised to receive ultrasound guided 5 or 20 ml ropivacaine 0.5% at the departure of the suprascapular nerve from the brachial plexus. Primary outcome was successful shoulder block-defined as cutaneous sensory affection of the axillary nerve and motor affection of the suprascapular nerve (>50% reduction in external rotation force measured with dynamometry). We used a non-inferiority margin of 20%. Secondary outcome was change in lung function measured with spirometry.

RESULTS

Thirteen of 16 (81.3%; 95% confidence interval [CI] 57.0% to 93.4%) in the 5 ml group and 15 of 16 (93.8%; 95% CI 71.7% to 98.9%) in the 20 ml group had successful shoulder block (p = .6). The ratio of the event rates of the 20 ml (standard) and 5 ml (intervention) groups was (15/16)/(13/16) = 0.937/0.813 = 1.15 (95% CI 0.88 to 1.51). All mean reductions in lung function parameters were non-significantly lower in the 5 ml group compared with the 20 ml group.

CONCLUSION

For our primary outcome, the 95% CI of the difference of event ratio included the non-inferiority margin. We are therefore unable to conclude that 5 ml LA is non-inferior to 20 ml LA with respect to block success rate.

Comparing bupivacaine alone to liposomal bupivacaine plus bupivacaine in interscalene blocks for total shoulder arthroplasty: a randomized, non-inferiority trial

Introduction

Interscalene brachial plexus blocks are a commonly performed procedure to reduce pain following total shoulder arthroplasty. Liposomal bupivacaine has been purported to prolong the duration of brachial plexus blocks for up to 72 hours; however, there has been controversy surrounding the analgesic benefits of this drug. Our hypothesis was that an interscalene block performed with bupivacaine alone would be non-inferior to a combination of liposomal bupivacaine and bupivacaine with respect to opioid consumption following total shoulder arthroplasty.

Methods

Subjects presenting for primary total shoulder arthroplasty were randomized in a 1:1 ratio to an ultrasound-guided, single-injection interscalene block with either a combination of liposomal bupivacaine and bupivacaine (LB group) or bupivacaine without additive (Bupi group). The primary outcome of this study was 72-hour postoperative cumulative opioid consumption (in oral morphine equivalents) with a non-inferiority margin of 22.5 mg. Secondary outcomes included pain scores, patient satisfaction with analgesia and patient reported duration of sensory block.

Results

Seventy-six subjects, 38 from the Bupi group and 38 from the LB group, completed the study. Analysis of the primary outcome showed a 72-hour cumulative geometric mean oral morphine equivalent consumption difference of 11.9 mg (95% CI −6.9 to 30.8) between groups (calculated on the log scale). This difference constitutes approximately 1.5 tablets of oxycodone over 3 days. No secondary outcomes showed meaningful differences between groups.

Discussion

Interscalene brachial plexus blocks performed with bupivacaine alone did not demonstrate non-inferiority compared to a mixture of liposomal bupivacaine plus bupivacaine with regards to 72-hour cumulative opioid consumption following total shoulder arthroplasty. However, the difference between groups did not appear to be clinically meaningful.

Continuous interscalene versus phrenic nerve-sparing high-thoracic erector spinae plane block for total shoulder arthroplasty: a randomized controlled trial

PURPOSE

The high-thoracic erector spinae plane block (HT-ESPB) has been reported as an effective analgesic modality for the shoulder region without phrenic nerve palsy. The goal of this study was to compare the HT-ESPB as a phrenic nerve-sparing alternative to an interscalene block for total shoulder arthroplasty.

METHODS

Thirty patients undergoing total shoulder arthroplasty at Stanford Health Care (Palo Alto, CA, USA) were enrolled in a double-blind randomized controlled trial. We randomized 28 patients to receive either an interscalene or HT-ESPB perineural catheter preoperatively; 26 patients were included in the final analysis. The study was powered for the primary outcome of incidence of hemidiaphragmatic paralysis in the postanesthesia care unit (PACU). Other outcome measures included incentive spirometry volume, brachial plexus motor and sensory exams, adverse events, pain scores, and opioid consumption.

RESULTS

The incidence of hemidiaphragmatic paralysis in the HT-ESPB catheter group was significantly lower than in the interscalene catheter group (0/12, 0% vs 14/14, 100%; P < 0.001). No statistically significant differences were found in pain scores and opioid consumption (in oral morphine equivalents) between the interscalene and HT-ESPB groups through postoperative day (POD) 2. Nevertheless, the mean (standard deviation) point estimates for opioid consumption for the HT-ESPB group were higher than for the interscalene group in the PACU (HT-ESPB: 24.8 [26.7] mg; interscalene: 10.7 [21.7] mg) and for POD 0 (HT-ESPB: 20.5 [25.0] mg; interscalene: 6.7 [12.0] mg). In addition, cumulative postoperative opioid consumption was significantly higher at POD 0 (PACU through POD 0) in the HT-ESPB group (45.3 [39.9] mg) than in the interscalene group (16.6 [21.9] mg; P = 0.04).

CONCLUSIONS

This study suggests that continuous HT-ESPB can be a phrenic nerve-sparing alternative to continuous interscalene brachial plexus blockade, although the latter provided superior opioid-sparing in the immediate postoperative period. This was a small sample size study, and further investigations powered to detect differences in analgesic and quality of recovery score endpoints are needed.

STUDY REGISTRATION

www.

CLINICALTRIALS

gov (NCT03807505); registered 17 January 2019.

Low volume proximal suprascapular nerve block after arthroscopic shoulder surgery - A randomised, controlled trial

BACKGROUND

A proximal suprascapular nerve block has been suggested as an alternative to an interscalene brachial plexus block after arthroscopic shoulder surgery. The aim of this randomised controlled trial was to compare the analgesic and opioid-sparing effect of a low volume proximal suprascapular nerve block with placebo in patients with moderate-to-severe pain after arthroscopic shoulder surgery.

METHODS

Patients with a VAS score equal to or above 50 during the first postoperative hour after planned arthroscopic shoulder surgery were included in the study. They were randomised to an ultrasound-guided proximal suprascapular nerve block with either 5 ml ropivacaine 7.5 mg/ml or 5 ml isotonic NaCl. Primary outcome was change in VAS score at rest from baseline to 30 min after the block procedure (T30). Secondary outcomes included total morphine consumption from 0-6 h after block procedure.

RESULTS

There was a significant difference in mean VAS reductions at T30 between the two groups favouring the ropivacaine group (-50.2 vs -26.8, p < .001). Total intravenous morphine consumption from 0-6 h after block procedure was significantly lower in the ropivacaine group compared to the placebo group (8.5 mg vs 18.5 mg, p < .01).

CONCLUSION

In this study, a proximal suprascapular nerve block with only 5 ml ropivacaine resulted in a substantial pain reduction and opioid-sparing effect in patients with VAS of 50 or more after arthroscopic shoulder surgery.

Anesthesia for the Patient Undergoing Shoulder Surgery

Shoulder surgery introduces important anesthesia considerations. The interscalene nerve block is considered the gold standard regional anesthetic technique and can serve as the primary anesthetic or can be used for postoperative analgesia. Phrenic nerve blockade is a limitation of the interscalene block and various phrenic-sparing strategies and techniques have been described. Patient positioning is another important anesthetic consideration and can be associated with significant hemodynamic effects and position-related injuries.

Ultrasound-Guided Phrenic Nerve Block for Lung Nodule Biopsy: Single-Center Initial Experience

RATIONALE AND OBJECTIVES

Biopsy of lung nodules in the lower lung fields can be difficult because of breathing motion. Ipsilateral phrenic nerve block (PNB) before biopsy should make the biopsy safer, easier, and more precisely targeted. We describe the use of ultrasound-guided PNB before lung nodule biopsy, including relevant anatomy and variations, complications, and technique, along with our first 40 cases.

MATERIALS AND METHODS

We retrospectively reviewed patients who underwent PNB before computed tomography (CT)- or ultrasound-guided lung nodule biopsy from April 2015 through March 2020. Patient demographics, CT fluoroscopy time, radiation dose, complications, diagnostic yield, and effectiveness of PNB were recorded. Effectiveness of PNB was based on direct observation of diaphragmatic motion. Control group data for biopsies during the same time frame were collected and matched with nodules ≤1 cm from the PNB group.

RESULTS

Among 40 patients identified, no complications occurred related to the PNB. Mean (SD) nodule size was 12.4 (6.2) mm. True-positive results were obtained in 39 patients (98%), with 1 false-negative after an ineffective PNB. PNB was effective in 70%. When CT fluoroscopy was used for the biopsy, radiation dose was significantly lower after an effective PNB than an ineffective PNB (p < .001). Effective PNB was significantly more common with injection of ≥4 mL of local anesthetic (p = .01). Comparison with 19 matched controls showed significantly fewer instances of pneumothorax (p = .02) and greater diagnostic success (p = .03) for the PNB group.

CONCLUSION

Ultrasound-guided PNB is safe and effective and can improve outcomes when used before lung nodule biopsy.

Evaluation of Diaphragmatic Function after Interscalene Block with Liposomal Bupivacaine: A Randomized Controlled Trial

Background

Interscalene blocks provide analgesia for shoulder surgery but also cause phrenic nerve paralysis. Liposomal bupivacaine is approved for use in interscalene blocks with the potential to provide longer pain control. However, the impact of liposomal bupivacaine on the phrenic nerve has not been evaluated. It was hypothesized that patients who received an interscalene block with both bupivacaine and liposomal bupivacaine would have a decreased diaphragmatic excursion when compared to bupivacaine alone at 24 h.

Methods

This was a double-blinded study of adult patients who were randomized to receive an interscalene block with either 20 ml 0.5% bupivacaine (bupivacaine group) or 10 ml 0.5% bupivacaine plus 10 ml liposomal bupivacaine (liposomal bupivacaine group). Twenty-six patients were randomized with 22 included in the analysis. Diaphragmatic excursion (via ultrasound) and spirometry were assessed before the block, in the postanesthesia care unit, and at 24 h postblock. The primary outcome was diaphragm excursion with sigh. No adverse events were observed.

Results

At 24 h, the liposomal bupivacaine group median [25th, 75th], had a greater percent change in diaphragmatic excursion during sigh breath compared to the bupivacaine group, –24% [–30, –9] versus 9% [–8, 26], difference in location, 32 (95% CI, 12 to 52), P = 0.007. Five patients in the liposomal bupivacaine group had a greater than 25% reduction in diaphragmatic excursion at 24 h versus zero in the bupivacaine group. They also had a significantly greater percent reduction in forced expiratory volume in 1 s and forced vital capacity compared with the bupivacaine group at 24 h (median decrease of 22% vs. 2%, P = 0.006, and median decrease of 19% vs. 1%, P = 0.049, respectively).

Conclusions

The addition of liposomal bupivacaine to bupivacaine in an interscalene block results in statistically significant reductions in diaphragm excursion and pulmonary function testing 24 h after block placement when compared to bupivacaine alone. This reduction, however, falls within the range of normal diaphragmatic function.

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Pain management in shoulder arthroplasty: a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Postoperative pain management after total shoulder arthroplasty (TSA) can be challenging. Given the variety of pain management options available, the purpose of this investigation was to systematically review the literature for randomized controlled trials reporting on pain control after shoulder arthroplasty. We sought to determine which modalities are most effective in managing postoperative pain and reducing postoperative opioid use.

METHODS

A systematic review was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. PubMed, Scopus, and the Cochrane Central Register of Controlled Trials were searched for Level I-II randomized controlled trials that compared interventions for postoperative pain control after TSA. Pain control measures included nerve blocks and nerve block adjuncts, local injections, patient-controlled analgesia, oral medications, and other modalities. The 2 primary outcome measures were pain level measured on a 0-10 visual analog scale and opioid use. The risk of study bias and methodologic quality were analyzed using The Cochrane Collaboration's Risk of Bias 2 (RoB 2) tool. Network meta-analyses were performed for visual analog scale pain scores at postsurgical time points and opioid use using a frequentist approach and random-effects model, with heterogeneity quantified using the I² statistic. Treatments were ranked using the P score, and statistical significance was set at P < .05.

RESULTS

The initial search yielded 2391 articles (695 duplicates, 1696 screened, 53 undergoing full-text review). Eighteen articles (1358 shoulders; 51% female patients; mean age range, 65-73.7 years; 4 studies with low risk of bias, 12 with some risk, and 2 with high risk) were included and analyzed. At 4 and 8 hours postoperatively, patients receiving local liposomal bupivacaine (LB) injection (P < .001 for 4 and 8 hours) or local ropivacaine injection (P < .001 for 4 hours and P = .019 for 8 hours) had significantly more pain compared with patients who received either a continuous interscalene block (cISB) or single-shot interscalene block (ssISB). No differences in opioid use (at P < .05) were detected between modalities. The P scores of treatments demonstrated that ssISBs were most favorable at time points < 24 hours, whereas pain at 24 and 48 hours after surgery was best managed with cISBs or a combination of an ssISB with a local LB injection.

CONCLUSION

Interscalene blocks are superior to local injections alone at managing pain after TSA. Single-shot interscalene blocks are optimal for reducing early postoperative pain (< 24 hours), whereas pain at 24-48 hours after surgery may be best managed with cISBs or a combination of an ssISB with a local LB injection.

Continuous bilateral subomohyoid suprascapular nerve blocks for postoperative analgesia for bilateral rotator cuff repair: a case report

PURPOSE

Blocking the suprascapular nerve under the inferior belly of the omohyoid muscle is a novel regional anesthesia technique that has been proposed for shoulder analgesia. We describe the use of and our experience with bilateral indwelling suprascapular catheters for pain management via continuous infusions in a patient undergoing bilateral shoulder surgery.

CLINICAL FEATURES

Bilateral subomohyoid suprascapular catheters were inserted prior to surgery for postoperative analgesia in a patient undergoing bilateral rotator cuff tear repair. The catheters were placed 0.5-1 cm beyond the needle tip, and low local anesthetic infusion rates (ropivacaine 0.2% at 5 mL·hr^-1 on each side) were used.

CONCLUSIONS

Judicious use of preoperatively placed bilateral suprascapular catheters added to a comprehensive multimodal analgesic regimen provided excellent analgesia without respiratory compromise throughout the perioperative course.

Cadaveric study investigating the phrenic-sparing volume for anterior suprascapular nerve block

BACKGROUND

This cadaveric study investigated the maximum effective volume of dye in 90% of cases (MEV90), required to stain the suprascapular nerve while sparing the phrenic nerve during the performance of an anterior suprascapular nerve block.

METHODS

In cadaveric neck specimens, using ultrasound guidance, the block needle was advanced until its tip was positioned underneath the omohyoid muscle next to the suprascapular nerve. The dye was injected in order to achieve circumferential spread around the latter. Successful phrenic-sparing suprascapular nerve block was defined as the non-staining of the phrenic nerve on dissection. Volume assignment was carried out using a Biased Coin Design, whereby the volume of dye administered to each cadaveric specimen depended on the response of the previous one. In case of failure (ie, stained phrenic nerve), the next one received a lower volume (defined as the previous volume with a decrement of 2 mL). If the previous cadaveric specimen had a successful block (ie, non-stained phrenic nerve), the next one was randomized to a higher volume (defined as the previous volume with an increment of 2 mL), with a probability of b=0.11, or the same volume, with a probability of 1 - b=0.89.

RESULTS

Thirty-one cadavers (56 cadaveric neck specimens) were included in the study. Using isotonic regression and bootstrap CI, the MEV90 for phrenic-sparing anterior suprascapular nerve block was estimated to be 4.2 mL (95% CI 3.0 to 5.0 mL). The probability of a successful response was estimated to be 0.90 (95% CI 0.84 to 0.96).

CONCLUSION

For ultrasound-guided anterior suprascapular nerve block, the MEV90 of dye required to spare the phrenic nerve is 4.2 mL. Further studies are required to correlate this finding with the MEV90 of local anesthetic in live subjects.

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.

Clinical effect of normal saline injectate into interscalene nerve block catheters given within one hour of local anesthetic bolus on analgesia and hemidiaphragmatic paralysis

BACKGROUND

Previous case reports describe the reversal of phrenic nerve blockade from the interscalene nerve block using normal saline injectate washout. This randomized clinical trial aimed to evaluate whether using normal saline injectate to wash out local anesthetic from an interscalene nerve block catheter would restore phrenic nerve and diaphragm function, while preserving analgesia.

METHODS

Institutional review board approval, clinical trial registration and consent were obtained for patients undergoing shoulder surgery with an interscalene nerve block catheter. 16 patients were randomized to receive three 10 mL aliquots of normal saline injectate (intervention group, n=8) or three sham injectates (control group, n=8) via their perineural catheters in the postanesthesia care unit (PACU). Primary outcome measures were the effects on ipsilateral hemidiaphragmatic paralysis, and secondary outcome measures included PACU opioid consumption, pain scores and change in brachial plexus sensory examination and motor function.

RESULTS

There was no significant difference in reversal of hemidiaphragmatic paralysis. However, there was a greater number of patients in the intervention group who ultimately displayed partial, as opposed to full, paralysis of the hemidiaphragm (p=0.03). There was no significant difference in pain scores, PACU opioid requirement, and brachial plexus motor and sensory examinations between the two groups.

CONCLUSIONS

All patients had persistent hemidiaphragmatic paralysis after the intervention, but fewer patients in the intervention group progressed to full paralysis, suggesting that a larger bolus dose of normal saline may be needed to completely reverse hemidiaphragmatic paralysis. Although normal saline injectate in 10mL increments given through the interscalene nerve block catheter had no clinically significant effect on reversing phrenic nerve blockade, it also did not lead to a reduction in analgesia and may be protective in preventing the progression to full hemidiaphragmatic paralysis.

TRAIL REGISTRATION NUMBER

NCT03677778.

Perioperative pain management for shoulder surgery: evolving techniques

Improving management of postoperative pain following shoulder surgery is vital for optimizing patient outcomes, length of stay, and decreasing addiction to narcotic medications. Multimodal analgesia (ie, controlling pain via multiple different analgesic methods with differing mechanisms) is an ever-evolving approach to enhancing pain control perioperatively after shoulder surgery. With a variety of options for the shoulder surgeon to turn to, this article succinctly reviews the pros and cons of each approach and proposes a potential pain management algorithm.

Randomized, controlled trial comparing respiratory and analgesic effects of interscalene, anterior suprascapular, and posterior suprascapular nerve blocks for arthroscopic shoulder surgery

Background

Interscalene brachial plexus block (ISB) provides excellent analgesia for arthroscopic shoulder surgeries but is associated with adverse effects including hemidiaphragmatic paresis. We aimed to compare the respiratory effects, forced vital capacity (FVC), and forced expiratory volume in 1 second (FEV1) between suprascapular nerve block (SSB) and ISB.

Methods

Sixty patients were recruited and randomized into ISB, anterior SSB, and posterior SSB groups. FVC, FEV1, and diaphragmatic excursion were evaluated at baseline and 30 minutes after intervention. Blocks were performed under ultrasound guidance with 15 ml of 0.5% ropivacaine. Pain scores were assessed at 1, 6, 12, and 24 hours postoperatively.

Results

The ISB group showed a reduced FVC of 31.2% ± 17.5% (mean ± SD), while the anterior and posterior SSB groups had less reduction of 3.6% ± 18.6% and 6.8% ± 6.5%, respectively (P < 0.001). The ISB group showed more reduction in diaphragmatic excursion than the anterior and posterior SSB groups (median [IQR]): −85.7% (−95.3% to −63.3%) vs. −1.8% (−13.1% to 2.3%) and −1.2% (−8.8% to 16.8%), respectively (P < 0.001). The median pain scores (IQR) in the ISB and anterior SSB groups were lower than those in the posterior SSB group at 6 hours on movement: 0 (0–2), 1.8 (0–4.5) vs. 5 (2.5–8), respectively (P = 0.002). There was no significant difference in oxycodone consumption postoperatively.

Conclusions

Anterior SSB preserves lung function and has a comparable analgesic effect as ISB. Thus, it is recommended for arthroscopic shoulder surgeries, especially in patients who have reduced lung function.

Analgesic efficacy of ultrasound-guided interscalene block vs. supraclavicular block for ambulatory arthroscopic rotator cuff repair: A randomised noninferiority study

BACKGROUND

Ultrasound-guided interscalene block (ISB) is the reference technique for pain control after ambulatory upper limb surgery, but supraclavicular block (SCB) is an alternative.

OBJECTIVES

The aim of this study was to compare the efficacy of SCB vs. ISB in patients undergoing ambulatory arthroscopic rotator cuff repair (ARCR), with the hypothesis of noninferiority of SCB analgesia compared with ISB.

DESIGN

A randomised, single-blind, noninferiority study.

SETTING

Hôpital Privé Jean Mermoz, Centre Paul Santy, Lyon, France.

PATIENTS

Ambulatory ARCR patients.

INTERVENTION

Patients were randomly allocated (1 : 1) to receive a single injection SCB or ISB, as well as general anaesthesia. All patients received a postoperative analgesic prescription for home use before leaving hospital (including fast-acting oral morphine sulphate). Patients completed a telephone questionnaire on days 1 and 2 postsurgery.

MAIN OUTCOME MEASURES

Primary endpoint was oral morphine consumption (mg) during the first 2 days postsurgery. If the difference between mean morphine consumption in the SCB vs. ISB group was less than 30 mg, noninferiority of SCB compared with ISB would be demonstrated. Secondary evaluation criteria included pain scores (numerical rating scale), duration of motor and sensory blockade, and satisfaction with treatment.

RESULTS

The per-protocol cohort included 103 patients (SCB = 52, ISB = 51) (57% men, median age 58 years). Mean morphine consumption in the 48 h postsurgery was 9.4 vs. 14.7 mg in the SCB and ISB groups, respectively (difference −5.3, P < 0.001). The upper limit of the 95% CI was less than 30 mg, demonstrating noninferiority of SCB compared with ISB. No difference was observed between the two groups in terms of pain scores or the duration of motor or sensory blockade. Overall, 98% of patients in the SCB group vs. 90% in the ISB group were satisfied with their treatment.

CONCLUSION

SCB is as effective as ISB in terms of postoperative analgesia based on oral morphine consumption in patients undergoing ambulatory ARCR.

TRIAL REGISTRATION

EudraCT number: 2016-A00747-47.

Is Supraclavicular Block as Good as Interscalene Block for Acute Pain Control Following Shoulder Surgery? A Systematic Review and Meta-analysis

BACKGROUND

Interscalene block (ISB) is the acute pain management technique of choice for shoulder surgery, but its undesirable respiratory side effects have prompted seeking alternatives. Supraclavicular block (SCB) is proposed as an ISB alternative, but evidence of comparative analgesic and respiratory-sparing effects is inconsistent. We compared the analgesic and respiratory effects of SCB and ISB for shoulder surgery.

METHODS

Trials comparing ISB to SCB for shoulder surgery were sought. We decided a priori that SCB would be an acceptable alternative if it were noninferior for (1) postoperative 24-hour cumulative oral morphine equivalent consumption (primary outcome, noninferiority margin Δ = -25 mg) and (2) postoperative pain (secondary outcome, noninferiority margin Δ = 4.0 cm·hour); and superior for (3) postblock respiratory dysfunction (primary outcome). Opioid-related side effects and block-related complications were also evaluated.

RESULTS

Fifteen studies (1065 patients) were analyzed. In single-injection blocks, SCB was noninferior to ISB for 24-hour morphine consumption (mean difference for SCB-ISB, MD [95% confidence interval {CI}] = -3.11 mg [-9.42 to 3.19], Δ = -25 mg); it was also noninferior for 24-hour pain scores (MD = 0.78 cm·hour [0.07-1.49], Δ = 4.0 cm·hour); and decreased the odds of respiratory dysfunction (odds ratio [OR] [95% CI] = 0.08 [0.01-0.68]). Similarly, in continuous blocks, SCB was noninferior to ISB for 24-hour morphine consumption (MD = 0.46 mg [-6.08 to 5.15], Δ = -25 mg), and decreased the odds of respiratory dysfunction (OR = 0.22 [0.08-0.57]). SCB also decreased odds of minor block-related complications (OR = 0.36 [0.20-0.68] and OR = 0.25 [0.15-0.41] for single-injection and continuous blocks, respectively). Consequently, the null joint-hypothesis was rejected, and SCB can be considered an acceptable alternative to ISB.

CONCLUSIONS

For acute pain control following shoulder surgery, high-quality evidence indicates that SCB can be used as an effective ISB alternative. SCB is noninferior for postoperative opioid consumption and acute pain, and it reduces the odds of postblock respiratory dysfunction.

Subomohyoid Anterior Suprascapular Block versus Interscalene Block for Arthroscopic Shoulder Surgery

Background

Interscalene brachial plexus block, the pain relief standard for shoulder surgery, is an invasive technique associated with important complications. The subomohyoid anterior suprascapular block is a potential alternative, but evidence of its comparative analgesic effect is sparse. The authors tested the hypothesis that anterior suprascapular block is noninferior to interscalene block for improving pain control after shoulder surgery. As a secondary objective, the authors evaluated the success of superior trunk (C5–C6 dermatomes) block with suprascapular block.

Methods

In this multicenter double-blind noninferiority randomized trial, 140 patients undergoing shoulder surgery were randomized to either interscalene or anterior suprascapular block with 15 ml of ropivacaine 0.5% and epinephrine. The primary outcome was area under the curve of postoperative visual analog scale pain scores during the first 24 h postoperatively. The 90% CI for the difference (interscalene-suprascapular) was compared against a –4.4-U noninferiority margin. Secondary outcomes included presence of superior trunk blockade, pain scores at individual time points, opioid consumption, time to first analgesic request, opioid-related side-effects, and quality of recovery.

Results

A total of 136 patients were included in the analysis. The mean difference (90% CI) in area under the curve of pain scores for the (interscalene-suprascapular) comparison was –0.3 U (–0.8 to 0.12), exceeding the noninferiority margin of –4.4 U and demonstrating noninferiority of suprascapular block. The risk ratio (95% CI) of combined superior trunk (C5–C6 dermatomes) blockade was 0.98 (0.92 to 1.01), excluding any meaningful difference in superior trunk block success rates between the two groups. When differences in other analgesic outcomes existed, they were not clinically important.

Conclusions

The suprascapular block was noninferior to interscalene block with respect to improvement of postoperative pain control, and also for blockade of the superior trunk. These findings suggest that the suprascapular block consistently blocks the superior trunk and qualify it as an effective interscalene block alternative.

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Continuous suprascapular nerve block compared with single-shot interscalene brachial plexus block for pain control after arthroscopic rotator cuff repair

OBJECTIVES

We compared the analgesic efficacy of a continuous suprascapular nerve block (C-SSNB) and a single-shot interscalene brachial plexus block (S-ISNB) for postoperative pain management in patients undergoing arthroscopic rotator cuff repair.

METHODS

A total of 118 patients undergoing arthroscopic rotator cuff repair were randomly allocated to the S-ISNB or C-SSNB groups. Postoperative pain was assessed using the visual analog scale (VAS) at 1, 2, 6, 12, and 24 h postoperatively. Supplemental analgesic use was recorded as total equianalgesic fentanyl consumption.

RESULTS

The C-SSNB group showed significantly higher VAS scores at 0-1 h and 1-2 h after the surgery than the S-ISNB group (4.9±2.2 versus 2.3±2.2; p<0.0001 and 4.8±2.1 versus 2.4±2.3; p<0.0001, respectively). The C-SSNB group showed significantly lower VAS scores at 6-12 h after the surgery than the S-ISNB group (4.1±1.8 versus. 5.0±2.5; p=0.031). The C-SSNB group required significantly higher doses of total equianalgesic fentanyl in the post-anesthesia care unit than the S-ISNB group (53.66±44.95 versus 5.93±18.25; p<0.0001). Total equianalgesic fentanyl in the ward and total equianalgesic fentanyl throughout the hospital period were similar between the groups (145.99±152.60 versus 206.13±178.79; p=0.052 and 199.72±165.50 versus 212.15±180.09; p=0.697, respectively).

CONCLUSION

C-SSNB was more effective than S-ISNB at 6-12 h after the surgery for postoperative analgesia after arthroscopic rotator cuff repair.

Adverse events associated with continuous interscalene block administered using the catheter-over-needle method: a retrospective analysis

Background

Continuous interscalene block is widely used for pain management in shoulder surgery. However, continuous interscalene block performed using the catheter-through-needle method is reportedly associated with adverse events such as pericatheter leakage of the local anesthetic, phrenic nerve paralysis, and hoarseness. Because we expected that the catheter-over-needle method would reduce these adverse events, we examined cases in which continuous interscalene block was performed using the catheter-over-needle method to determine what adverse events occurred and when.

Methods

We retrospectively reviewed the anesthesia and medical records of adult patients who underwent catheter insertion to receive a continuous interscalene block performed using the catheter-over-needle method at our hospital from July 2015 to July 2017.

Results

During the surveillance period, 122 adult patients underwent catheter insertion to receive a continuous interscalene block administered using the catheter-over-needle method. No case of pericatheter local anesthetic leakage was observed. Adverse events, such as dyspnea, hoarseness, insufficient anesthetic effect, dizziness, cough reflex during drinking, or ptosis, were observed in 42 patients (34.4%; 95% confidence interval 26–42.7). Most of the adverse events occurred on postoperative day 2. The median time between surgery and the onset of adverse events was 28.5 h.

Conclusions

The catheter-over-needle method may prevent the pericatheter leakage of the local anesthetic. However, adverse events occurred in more than one-third of the patients. During continuous interscalene block, patients must be carefully observed for adverse events, especially on postoperative day 2.

Trial registration

This study was registered at the UMIN Clinical Trials Registry on August 13th, 2019 (UMIN000037673).

Diaphragm-sparing nerve blocks for shoulder surgery, revisited

Although interscalene brachial plexus block (ISB) remains the gold standard for analgesia after shoulder surgery, the inherent risks of ipsilateral phrenic nerve block and hemidiaphragmatic paralysis (HDP) limit its use in patients with preexisting pulmonary compromise. In a previous Daring Discourse (2017), our research team has identified potential diaphragm-sparing alternatives to ISB for patients undergoing shoulder surgery. In recent years, the field has been fertile with research, with the publication of multiple randomized controlled trials investigating supraclavicular blocks, upper trunk blocks, anterior suprascapular nerve blocks, costoclavicular blocks, and combined infraclavicular-suprascapular blocks. To date, the cumulative evidence (pre-2017 and post-2017) suggests that costoclavicular blocks may provide similar postoperative analgesia to ISB coupled with a 0%-incidence of HDP. However, in light of the small number of patients recruited by the single study investigating costoclavicular blocks, further confirmatory trials are required. Moreover, future investigation should also be undertaken to determine if costoclavicular blocks could achieve surgical anesthesia for shoulder surgery. Anterior suprascapular nerve blocks have been demonstrated to provide surgical anesthesia and similar analgesia to ISB. However, their risk of HDP has not been formally quantified. Of the remaining diaphragm-sparing nerve blocks, supraclavicular blocks (with local anesthetic injection posterolateral to the brachial plexus), upper trunk blocks, and combined infraclavicular-anterior suprascapular blocks merit further investigation, as they have been shown to achieve similar analgesia to ISB, coupled with an HDP incidence <10%.

Novel Regional Anesthesia for Outpatient Surgery

PURPOSE OF REVIEW

Peripheral nerve blocks are effective and safe modalities for perioperative analgesia. But it remains unclear what blocks are adequate for ambulatory surgeries, as well as the proper patient management before and after discharge.

RECENT FINDINGS

Emerging nerve blocks have sparked interests due to ease to perform under ultrasound guidance and lower risks of adverse events. Some of these novel blocks are particularly suitable for ambulatory procedures, including but not limited to motor-sparing lower extremity nerve blocks and phrenic-sparing nerve blocks for shoulder surgeries. The adoption of peripheral nerve block into outpatient surgery is a multidisciplinary effort that encompasses appropriate patient choice, careful selection of nerve blocks that minimize potential adverse events after discharge, and proper patient follow-up until block effects resolve.

Randomized comparison between interscalene and costoclavicular blocks for arthroscopic shoulder surgery

BACKGROUND

This randomized trial compared ultrasound-guided interscalene block (ISB) and costoclavicular brachial plexus block (CCB) for arthroscopic shoulder surgery. We hypothesized that CCB would provide equivalent analgesia to ISB 30 min after surgery without the risk of hemidiaphragmatic paralysis.

METHODS

All 44 patients received an ultrasound-guided block of the intermediate cervical plexus. Subsequently, they were randomized to ISB or CCB. The local anesthetic agent (20 mL of levobupivacaine 0.5% and epinephrine 5 µg/mL) and pharmacological block adjunct (4 mg of intravenous dexamethasone) were identical for all study participants. After the block performance, a blinded investigator assessed ISBs and CCBs every 5 min until 30 min using a composite scale that encompassed the sensory function of the supraclavicular nerves, the sensorimotor function of the axillary nerve and the motor function of the suprascapular nerve. A complete block was defined as one displaying a minimal score of six points (out of a maximum of eight points) at 30 min. Onset time was defined as the time required to reach the six-point minimal composite score. The blinded investigator also assessed the presence of hemidiaphragmatic paralysis at 30 min with ultrasonography.Subsequently, all patients underwent general anesthesia. Postoperatively, a blinded investigator recorded pain scores at rest at 0.5, 1, 2, 3, 6, 12, and 24 hours. Patient satisfaction at 24 hours, consumption of intraoperative and postoperative narcotics, and opioid-related side effects (eg, nausea/vomiting, pruritus) were also tabulated.

RESULTS

Both groups displayed equivalent postoperative pain scores at 0.5, 1, 2, 3, 6, 12, and 24 hours. ISB resulted in a higher incidence of hemidiaphragmatic paralysis (100% vs 0%; P < 0.001) as well as a shorter onset time (14.0 (5.0) vs 21.6 (6.4) minutes; p<0.001). However, no intergroup differences were found in terms of proportion of patients with minimal composite scores of 6 points at 30 min, intraoperative/postoperative opioid consumption, side effects, and patient satisfaction at 24 hours.

CONCLUSION

Compared to ISB, CCB results in equivalent postoperative analgesia while circumventing the risk of hemidiaphragmatic paralysis. Further confirmatory trials are required. Future studies should also investigate if CCB can provide surgical anesthesia for arthroscopic shoulder surgery.

CLINICAL TRIALS REGISTRATION

NCT03411343.

“Pseudo-suprascapular notch”: is it a sonographic trap in suprascapular nerve block?

Background and objectives

The aim of the study was to describe the radiological anatomy of the pseudo-suprascapular notch—a structure localized at the floor of the supraspinatus fossa, just below the true suprascapular notch. In sonographic examination, it may imitate the suprascapular notch leading to misidentification of these structures.

Methods

Ultrasound assessment of the suprascapular notch region was performed in 100 patients who underwent chest CT due to other indications. The presence of the suprascapular notch and the pseudo-suprascapular notch was evaluated together with their maximal width and depth using both techniques. The correlation between the dimensions of these two notches was assessed.

Results

The pseudo-suprascapular notch was recognized in 82 patients. In four of them the suprascapular notch could not be visualized in ultrasound due to obscuring clavicle. In all cases the pseudo-suprascapular notch contained a small artery. In comparison to the suprascapular notch, the pseudo-suprascapular notch was significantly narrower and shallower, except for 10 cases with vestigial suprascapular notch where the pseudo-suprascapular notch was the only hollow in this region. The dimensions of both structures did not correlate with each other. Finally, the pseudo-suprascapular notch did not present any significant asymmetry (p=0.1185) or sexual dimorphism (43 women vs 38 men, p=0.2025).

Conclusions

The pseudo-suprascapular notch is a hollow for nutrient vessels that can be mistaken for the regular suprascapular notch in cases of difficult sonographic navigation.

Comparison of Anterior Suprascapular, Supraclavicular, and Interscalene Nerve Block Approaches for Major Outpatient Arthroscopic Shoulder Surgery

Background

The interscalene nerve block provides analgesia for shoulder surgery, but is associated with diaphragm paralysis. One solution may be performing brachial plexus blocks more distally. This noninferiority study evaluated analgesia for blocks at the supraclavicular and anterior suprascapular levels, comparing them individually to the interscalene approach.

Methods

One hundred-eighty-nine subjects undergoing arthroscopic shoulder surgery were recruited to this double-blind trial and randomized to interscalene, supraclavicular, or anterior suprascapular block using 15 ml, 0.5% ropivacaine. The primary outcome was numeric rating scale pain scores analyzed using noninferiority testing. The predefined noninferiority margin was one point on the 11-point pain scale. Secondary outcomes included opioid consumption and pulmonary assessments.

Results

All subjects completed the study through the primary outcome analysis. Mean pain after surgery was: interscalene = 1.9 (95% CI, 1.3 to 2.5), supraclavicular = 2.3 (1.7 to 2.9), suprascapular = 2.0 (1.4 to 2.6). The primary outcome, mean pain score difference of supraclavicular–interscalene was 0.4 (–0.4 to 1.2; P = 0.088 for noninferiority) and of suprascapular–interscalene was 0.1 (–0.7 to 0.9; P = 0.012 for noninferiority). Secondary outcomes showed similar opioid consumption with better preservation of vital capacity in the anterior suprascapular group (90% baseline [P &lt; 0.001]) and the supraclavicular group (76% [P = 0.002]) when compared to the interscalene group (67%).

Conclusions

The anterior suprascapular block, but not the supraclavicular, provides noninferior analgesia compared to the interscalene approach for major arthroscopic shoulder surgery. Pulmonary function is best preserved with the anterior suprascapular nerve block.

Pain Management Strategies in Shoulder Arthroplasty

Pain control in total shoulder arthroplasty demands a multidisciplinary approach with collaboration between patients, surgeon, and anesthetist. A multimodal approach with preemptive medication, regional blockade, local anesthetics, and a combination of acetaminophen, nonsteroidal antiinflammatory drugs, tramadol, and gabapentinoids postoperatively leads to pain control and patient satisfaction. Assessment of patients' expectations constitutes a vital aspect of the preoperative patient evaluation. Educating and psychologically preparing patients reduces postoperative pain. Patients with anxiety and depression, preoperative narcotic use, and medical comorbidities are at an increased risk for suboptimal pain control. Minimizing narcotic use decreases opioid-related adverse effects and facilitates productive rehabilitation efforts.