Comparison Between Ultrasound-Guided Supraclavicular and Interscalene Brachial Plexus Blocks in Patients Undergoing Arthroscopic Shoulder Surgery: A Prospective, Randomized, Parallel Study

Diaphragmatic and Pulmonary Functions Following an Ultrasound-Guided Supraclavicular Approach Versus a Costoclavicular Approach of a Brachial Plexus Block: A Randomized Study

INTRODUCTION

A costoclavicular brachial plexus block is an emerging infraclavicular approach that targets the cords lateral to the axillary artery, providing rapid onset of sensory-motor blockade. However, the incidence of hemi-diaphragmatic paralysis (HDP), a potential complication, remains unclear compared to the widely used supraclavicular (SC) approach. This study aimed to compare the incidence of HDP between ultrasound-guided costoclavicular and SC brachial plexus blocks.

OBJECTIVES

To compare the influence of ultrasound-guided SC and costoclavicular brachial plexus blocks on diaphragmatic excursion, thickness, and contractility along with pulmonary function.

MATERIALS AND METHODS

 This prospective, randomized, observer-blinded controlled trial included 60 patients undergoing below-shoulder surgeries. Patients were randomized to receive either ultrasound-guided SC (Group S) or costoclavicular (Group C) brachial plexus block with 0.5% levobupivacaine. The diaphragmatic function was assessed using ultrasonographic evaluation of diaphragm thickness and diaphragmatic thickness fraction (DTF) pre- and postblock. Pulmonary function tests (PFTs) (forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow rate (PEFR)) were performed preblock and two hours postblock. Block characteristics were compared.

RESULTS

The SC group exhibited a significantly larger reduction in DTF from preblock to postblock compared to the costoclavicular group (mean ΔDTF: 34.38% vs. 14.01%, p<0.01). Both groups showed significant declines in FVC, FEV1, and PEFR postblock, but the magnitude of deterioration was significantly greater in the SC group, displaying no significant difference in block characteristics.

CONCLUSION

The costoclavicular brachial plexus block demonstrated superior preservation of diaphragmatic contractility and lesser deterioration of PFTs compared to the SC approach while being equally effective. These findings highlight the potential benefits of the costoclavicular technique in minimizing diaphragmatic dysfunction and respiratory impairment, particularly in patients at risk for respiratory complications.

Eighth Cervical Nerve Root Block During Interscalene Brachial Plexus Block Decreases Pain Caused by Posterior Portal Placement but Increases Horner Syndrome in Patients Undergoing Arthroscopic Shoulder Surgery: A Randomized Controlled Trial

PURPOSE

To compare the intensity of pain on posterior portal placement between a C5-C7 root block (conventional interscalene brachial plexus block [ISBPB]) and a C5-C8 root block in patients undergoing arthroscopic shoulder surgery.

METHODS

In this prospective, single-blinded, parallel-group randomized controlled trial, patients were randomized to receive either a C5-C7 root block (C5-C7 group, n = 37) or a C5-C8 root block (C5-C8 group, n = 36) with 25 mL of 0.75% ropivacaine. The primary outcome was the pain intensity on posterior portal placement, which was graded as 0 (no pain), 1 (mild pain), or 2 (severe pain). The secondary outcomes were the bilateral pupil diameters measured 30 minutes after ISBPB placement; the incidence of Horner syndrome, defined as a difference in pupil diameter (ipsilateral - contralateral) of less than -0.5 mm; the onset of postoperative pain; and the postoperative numerical rating pain score, where 0 and 10 represent no pain and the worst pain imaginable, respectively.

RESULTS

Fewer patients reported mild or severe pain on posterior portal placement in the C5-C8 group than in the C5-C7 group (9 of 36 [25.0%] vs 24 of 37 [64.9%], P = .003). Less pain on posterior portal placement was reported in the C5-C8 group than in the C5-C7 group (median [interquartile range], 0 [0-0.75] vs 1 [0-1]; median difference [95% confidence interval], 1 [0-1]; P = .001). The incidence of Horner syndrome was higher in the C5-C8 group than in the C5-C7 group (33 of 36 [91.7%] vs 22 of 37 [59.5%], P = .001). No significant differences in postoperative numerical rating pain scores and onset of postoperative pain were found between the 2 groups.

CONCLUSIONS

A C5-C8 root block during an ISBPB reduces the pain intensity on posterior portal placement. However, it increases the incidence of Horner syndrome with no improvement in postoperative pain compared with the conventional ISBPB (C5-C7 root block).

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

The upper extremity regional anaesthesia trifecta: three upper extremity nerve blocks for awake upper-limb surgery in a patient with a history of contralateral pneumonectomy

While regional anaesthesia plays a pivotal role in the perioperative management of patients undergoing upper extremity surgery, its utility can be limited by the risk of hemi-diaphragmatic paresis. Furthermore, each approach to blocking the brachial plexus has associated limitations that may result in incomplete upper extremity anaesthesia. We describe the combination of three upper extremity nerve blocks to achieve surgical anaesthesia of the whole arm for a patient who had previously undergone a contralateral pneumonectomy. On this occasion, she required upper arm lipectomy and arteriovenous fistula formation. Adequate blockade was achieved with no significant perioperative complications. This case demonstrates the potential of this approach for patients with respiratory compromise undergoing upper limb procedures.

Investigation of cryotherapy for pain relief after arthroscopic shoulder surgery

BACKGROUND

Recently, cryotherapy has become a common practice for postoperative pain management. The current accepted practice in Japan is the use of cryotherapy at 5 °C after arthroscopic shoulder surgery. However, this therapy has been reported to be highly intense because the sustained low temperature causes discomfort for patients. The optimum temperature and duration of cooling required for comfortable and effective cryotherapy after arthroscopic shoulder surgery were investigated.

METHODS

Because pain levels might differ depending on the condition, we selected 52 patients with rotator cuff injuries, which were the most common disorders indicated for arthroscopic shoulder surgery. Patients were treated with cryotherapy at 5 °C or 10 °C for 16 h or 24 h. The pain level was determined using the visual analogue scale, and deep shoulder joint temperatures were recorded at different time points for analysis.

RESULTS

Pain after arthroscopic shoulder surgery was found to be related to the presence of a brachial plexus block using the interscalene approach during surgical anesthesia. To obtain effective analgesia with cryotherapy, the cooling temperature and duration of cryotherapy had to be changed based on the presence or absence of the brachial plexus block. Patients who received brachial plexus blocks had the lowest recorded pain scores after receiving cryotherapy at 5 °C for 24 h after surgery. Patients who did not receive the block had the lowest recorded pain scores when receiving cryotherapy at either 5 °C for 16 h or 10 °C for 24 h.

CONCLUSIONS

Using universal cryotherapy intensity and duration settings regardless of the use of other interventions is likely to unintentionally increase postoperative pain levels. This study revealed that cryotherapy at 5 °C for 24 h was optimal for patients who received an anesthesia block and at 5 °C for 16 h or at 10 °C for 24 h for those who did not receive the anesthesia block. These results can be used as a reference for setting the temperature and duration of cryotherapy after arthroscopic shoulder surgery.

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.

Hemidiaphragmatic paralysis following costoclavicular versus supraclavicular brachial plexus block: a randomized controlled trial

Costoclavicular brachial plexus block is emerging as a promising infraclavicular approach performed just below the clavicle. However, there are relatively little data regarding the hemidiaphragmatic paralysis (HDP) compared to the commonly performed supraclavicular block. We hypothesized that the incidence of HDP in costoclavicular block is lower than supraclavicular block like classical infraclavicular approach. Eighty patients were randomly assigned to ultrasound-guided supraclavicular (group S) or costoclavicular (group C) block with 25 mL of local anesthetics (1:1 mixture of 1% lidocaine and 0.75% ropivacaine). The primary outcome was the incidence of HDP, defined as less than 20% of fractional change in the diaphragm thickness on ultrasound M-mode. Also, pulmonary function test and chest radiograph were assessed before and after the surgery. The incidence of HDP was 4/35 (11.4%) in the group C and 19/40 (47.5%) in the group S (risk difference, − 36%; 95% CI − 54 to − 17%; P = 0.002). The mean (SD) change of DTF values were 30.3% (44.0) and 56.9% (39.3) in the group C and S, respectively (difference in means, − 26.6%; 95% CI − 45.8 to − 7.4%; P = 0.007). The pulmonary function was more preserved in group C than in group S. The determined diagnostic cut off value of the diaphragm elevation on chest radiograph was 29 mm. Despite the very contiguous location of the two approaches around the clavicle, costoclavicular block can significantly reduce the risk of HDP compared with supraclavicular block.

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.

Local Anesthetic-Induced Central Nervous System Toxicity during Interscalene Brachial Plexus Block: A Case Series Study of Three Patients

Local anesthetics are commonly administered by nuchal infiltration to provide a temporary interscalene brachial plexus block (ISB) in a surgical setting. Although less commonly reported, local anesthetics can induce central nervous system toxicity. In this case study, we present three patients with acute central nervous system toxicity induced by local anesthetics applied during ISB with emphasis on neurological symptoms, key neuroradiological findings and functional outcome. Medical history, clinical and imaging findings, and outcome of three patients with local anesthetic-induced toxic left hemisphere syndrome during left ISB were analyzed. All patients were admitted to our neurological intensive care unit between November 2016 and September 2019. All three patients presented in poor clinical condition with impaired consciousness and left hemisphere syndrome. Electroencephalography revealed slow wave activity in the affected hemisphere of all patients. Seizure activity with progression to status epilepticus was observed in one patient. In two out of three patients, cortical FLAIR hyperintensities and restricted diffusion in the territory of the left internal carotid artery were observed in magnetic resonance imaging. Assessment of neurological severity scores revealed spontaneous partial reversibility of neurological symptoms. Local anesthetic-induced CNS toxicity during ISB can lead to severe neurological impairment and anatomically variable cerebral lesions.

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.

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.

Effect of local anesthetic volume (20 mL vs 30 mL ropivacaine) on electromyography of the diaphragm and pulmonary function after ultrasound-guided supraclavicular brachial plexus block: a randomized controlled trial

BACKGROUND AND OBJECTIVES

Diaphragmatic paralysis following supraclavicular brachial plexus block (SCBPB) is ascribed to phrenic nerve palsy. This study investigated the effect of 2 volumes of 0.375% ropivacaine on efficacy of block as a surgical anesthetic and as an analgesic and examined diaphragm compound muscle action potentials (CMAPs) and pulmonary function before and after SCBPB.

METHODS

Eighty patients scheduled for removal of hardware for internal fixation after healing of an upper limb fracture distal to the shoulder were randomized to receive ultrasound-guided SCBPC for surgical anesthesia with 20 mL (Group A) or 30 mL (Group B) 0.375% ropivacaine. The latency and amplitude of diaphragm CMAPs and forced vital capacity (FVC), FVC% predicted, and forced expiratory volume in 1 s (FEV1) were measured before and 30 min after SCBPB.

RESULTS

Block success as primary anesthetic in addition to analgesia was 81% in Group A and 91% in Group B. There were no obvious differences in the effectiveness of analgesia between the two groups. The mean time to onset of motor block was significantly longer in Group A (8.1±2.7 min) than in Group B (5.4 ± 2.8 min; p<0.05). The mean amplitude of the diaphragm CMAP was significantly lower in Group B than in Group A (p=0.03). The changes in FVC (Group A, - 8.1% vs Group B, -16.5%), FVC% (Group A, -8.0% vs Group B, -17.1%), and FEV1 (Group A, -9.5% vs Group B, -15.2%) from pre-SCBPB to post-SCBPB were significantly less in Group A than in Group B (all p=0.03).

CONCLUSIONS

The incidence rates of phrenic nerve palsy and diaphragm paralysis were reduced, and lung function was less impaired in patients who received 20 mL vs 30 mL of 0.375% ropivacaine without any differences in block success. Selecting a lower volume of anesthetic for nerve block may be especially beneficial in obese patients or patients with cardiopulmonary disease.

TRIAL REGISTRATION NUMBER

ChiCTR-IND-17012166.

[Hemidiaphragmatic paralysis after ultrasound-guided supraclavicular block: a prospective cohort study]

BACKGROUND AND OBJECTIVES

The frequent onset of hemidiaphragmatic paralysis during interscalene block restricts its use in patients with respiratory insufficiency. Supraclavicular block could be a safe and effective alternative. Our primary objective was to assess the incidence of hemidiaphragmatic paralysis following ultrasound-guided supraclavicular block and compare it to that of interscalene block.

METHODS

Adults warranting elective shoulder surgery under regional anesthesia (Toulouse University Hospital) were prospectively enrolled from May 2016 to May 2017 in this observational study. Twenty millilitres of 0.375% Ropivacaine were injected preferentially targeted to the "corner pocket". Diaphragmatic excursion was measured by ultrasonography before and 30 minutes after regional anesthesia. A reduction ≥ 25% in diaphragmatic excursion during a sniff test defined the hemidiaphragmatic paralysis. Dyspnoea and hypoxaemia were recorded in the recovery room. Predictive factors of hemidiaphragmatic paralysis (gender, age, weight, smoking, functional capacity) were explored. Postoperative pain was also analysed.

RESULTS

Forty-two and 43 patients from respectively the supraclavicular block and interscalene block groups were analysed. The incidence of hemidiaphragmatic paralysis was 59.5% in the supraclavicular block group compared to 95.3% in the interscalene block group (p < 0.0001). Paradoxical movement of the diaphragm was more common in the interscalene block group (RR = 2, 95% CI 1.4-3; p = 0.0001). A similar variation in oxygen saturation was recorded between patients with and without hemidiaphragmatic paralysis (p = 0.08). No predictive factor of hemidiaphragmatic paralysis could be identified. Morphine consumption and the highest numerical rating scale (NRS) at 24 hours did not differ between groups.

CONCLUSIONS

Given the frequent incidence of hemidiaphragmatic paralysis following supraclavicular block, this technique cannot be recommended for patients with an altered respiratory function.

Does Rebound Pain after Peripheral Nerve Block for Orthopedic Surgery Impact Postoperative Analgesia and Opioid Consumption? A Narrative Review

Regional anesthesia has been considered a great tool for maximizing post-operative pain control while minimizing opioid consumption. Post-operative rebound pain, characterized by hyperalgesia after the peripheral nerve block, can however diminish or negate the overall benefit of this modality due to a counter-productive increase in opioid consumption once the block wears off. We reviewed published literature describing pathophysiology and occurrence of rebound pain after peripheral nerve blocks in patients undergoing orthopedic procedures. A search of relevant keywords was performed using PubMed, EMBASE, and Web of Science. Twenty-eight articles (n = 28) were included in our review. Perioperative considerations for peripheral nerve blocks and other alternatives used for postoperative pain management in patients undergoing orthopedic surgeries were discussed. Multimodal strategies including preemptive analgesia before the block wears off, intra-articular or intravenous anti-inflammatory medications, and use of adjuvants in nerve block solutions may reduce the burden of rebound pain. Additionally, patient education regarding the possibility of rebound pain is paramount to ensure appropriate use of prescribed pre-emptive analgesics and establish appropriate expectations of minimized opioid requirements. Understanding the impact of rebound pain and strategies to prevent it is integral to effective utilization of regional anesthesia to reduce negative consequences associated with long-term opioid consumption.

Effects of C8 nerve root block during interscalene brachial plexus block on anesthesia of the posterior shoulder in patients undergoing arthroscopic shoulder surgery: study protocol for a prospective randomized parallel-group controlled trial

Background

A classical approach to produce interscalene brachial plexus block (ISBPB) consistently spares the posterior aspect of the shoulder and ulnar sides of the elbow, forearm, and hand, which are innervated by the lower trunk of the brachial plexus (C8–T1). As an alternative to the classical approach, a caudal approach to ISBPB successfully produces anesthesia of the ulnar sides of the elbow, forearm, and hand. However, its beneficial effects on anesthesia in the posterior aspect of the shoulder have not been investigated. In addition, the C8 nerve root is not routinely selectively blocked during ISBPB. Therefore, we will compare the C5 to C7 and C5 to C8 nerve root blocks during a caudal approach to ISBPB to assess the clinical benefit of C8 nerve blocks for the surgical anesthesia of the posterior aspect of the shoulder.

Methods/design

In this prospective parallel-group single-blind randomized controlled trial, 74 patients scheduled to undergo arthroscopic shoulder surgery under ISBPB are randomly allocated to receive the C5 to C7 or C5 to C8 nerve root block at a 1:1 ratio. The primary outcome is pain intensity, which is rated as 0 (no pain), 1 (mild pain), or 2 (severe pain), during the introduction of a posterior portal into the glenohumeral joint. The secondary outcomes are (1) the extent of the ipsilateral sensory, motor, hemidiaphragmatic, and stellate ganglion blockade, (2) changes in the results of a pulmonary function test, (3) incidence of complications related to ISBPB, (4) postoperative numerical pain rating scale scores, (5) patients’ satisfaction with the ISBPB, (6) dose and frequency of analgesic use, and (7) incidence of conversion to general anesthesia.

Discussion

This study is the first to evaluate the beneficial effects of the C8 nerve root block during ISBPB, which has rarely been performed due to the technical challenge in visualizing and blocking the C8 nerve root. It is expected that a C8 nerve root block performed during ISBPB will provide sufficient surgical anesthesia of the posterior aspect of the shoulder, which cannot be achieved by a classical approach to ISBPB.

Trial registration

ClicnicalTrials.gov, NCT03487874. Registered on 4 April 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3624-9) contains supplementary material, which is available to authorized users.

Upper trunk block for shoulder analgesia with potential phrenic nerve sparing: a preliminary anatomical report

BACKGROUND AND OBJECTIVES

Ipsilateral phrenic nerve palsy (PNP) is an undesirable side of conventional approaches to interscalene brachial plexus blocks. The purpose of this study was to demonstrate whether or not the phrenic nerve can be spared by dye when injected at the division of the upper trunk of the brachial plexus.

METHODS

Under ultrasound guidance, 5 mL of radiolabeled dye was injected between the anterior and posterior division of the upper trunk in two fresh, cryopreserved cadavers. CT scan analysis, cadaveric dissection, and cryosectioning were performed to examine the spread of the injectate.

RESULTS

We found staining of the injectate over the entire upper trunk with its anterior and posterior divisions, the suprascapular nerve under the omohyoid muscle and the lateral pectoralis nerve, and the C5 and C6 roots. The middle trunk was partially stained. There was no evidence of dye staining of the lower trunk, anterior aspect of the anterior scalene muscle, or the phrenic nerve.

CONCLUSIONS

Our study offers an anatomical basis for the possibility of providing shoulder analgesia and avoiding a PNP.

Acute postoperative pain after arthroscopic rotator cuff surgery: A review of methods of pain assessment

INTRODUCTION

Pain can be severe during the first days after arthroscopic surgery, and acute pain is an important outcome in clinical trials of surgical technique or anaesthetic strategy. A standardized, validated method of assessing acute postoperative pain would improve the quality of clinical studies, and facilitate systematic reviews and meta-analyses. A step on the way towards this standard is to investigate the methods most commonly used in recent literature.

METHODS

PubMed and CINAHL databases were searched, including studies of arthroscopic rotator cuff surgery with a primary pain-related outcome during the first postoperative week, published in English from 2012 to 2017.

RESULTS

A total of 47 studies were included, all measuring pain intensity using a pain rating scale. Most frequently used was the visual analogue scale using the anchors "no pain" and "worst pain imaginable", with recordings at 1, 2, 4, 6, 8, 12, and 24 hours postoperatively. A total of 34 studies recorded analgesic consumption, usually as average cumulated consumption in mg. Time to first analgesic request or first pain were recorded in 11 studies, and 4 different starting points were used.

DISCUSSION

This review describes the currently most common methods of assessing acute postoperative pain in clinical trials of arthroscopic shoulder surgery involving rotator cuff repair, and the large variety of methods applied. Based on this study and international guidelines, several recommendations on how to measure and report postoperative pain outcomes in future trials are proposed.

Pre- or postoperative interscalene block and/or general anesthesia for arthroscopic shoulder surgery: a retrospective observational study

PURPOSE

Arthroscopic shoulder surgery can be performed with an interscalene brachial plexus block (ISBPB) alone, ISBPB combined with general anesthesia (GA), or GA alone. Postoperative pain is typically managed with opioids; however, both GA and opioids have adverse effects which can delay discharge. This retrospective study compares the efficacy of four methods of anesthesia management for arthroscopic shoulder surgery.

METHODS

Charts of all patients who underwent shoulder surgery by a single surgeon from 2012-2015 were categorized by analgesic regimen: GA only (n = 177), single-shot ISBPB only (n = 124), or pre- vs postoperative ISBPB combined with GA (ISBPB + GA [n = 72] vs GA + ISBPB [n = 52], respectively). The primary outcome measure was the time to discharge from the postanesthesia care unit (PACU).

RESULTS

Mean (SD) time in the PACU ranged from 70.5 (39.9) min for ISBPB only to 111.2 (56.9) min for GA only. Use of ISBPB in any combination and regardless of timing resulted in significantly reduced PACU time, with a mean drop of 27.2 min (95% confidence interval [CI], 17.3 to 37.2; P < 0.001). The largest mean pairwise difference was between GA only and ISBPB only, with a mean difference of 40.7 min (95% CI, 25.5 to 55.8; P < 0.001). Use of ISBPB also reduced pain upon arrival at the PACU and, in some cases, upon discharge from the PACU (i.e., ISBPB only but not ISBPB + GA compared with GA). An ISBPB (alone or prior to GA) also reduced analgesic requirements.

CONCLUSION

Previously reported benefits of an ISBPB for arthroscopic shoulder surgery are confirmed. Postoperative ISBPBs may also be beneficial for reducing pain and opioid requirements and could be targeted for patients in severe pain upon emergence. A sufficiently powered randomized-controlled trial could determine the relative efficacy, safety, and associated financial implications associated with each method.

Phrenic Nerve Palsy and Regional Anesthesia for Shoulder Surgery

Regional anesthesia has an established role in providing perioperative analgesia for shoulder surgery. However, phrenic nerve palsy is a significant complication that potentially limits the use of regional anesthesia, particularly in high-risk patients. The authors describe the anatomical, physiologic, and clinical principles relevant to phrenic nerve palsy in this context. They also present a comprehensive review of the strategies for reducing phrenic nerve palsy and its clinical impact while ensuring adequate analgesia for shoulder surgery. The most important of these include limiting local anesthetic dose and injection volume and performing the injection further away from the C5–C6 nerve roots. Targeting peripheral nerves supplying the shoulder, such as the suprascapular and axillary nerves, may be an effective alternative to brachial plexus blockade in selected patients. The optimal regional anesthetic approach in shoulder surgery should be tailored to individual patients based on comorbidities, type of surgery, and the principles described in this article.

A comparison of ultrasound-guided interscalene and supraclavicular blocks for post-operative analgesia after shoulder surgery

BACKGROUND

In contrast to interscalene block, there was little information regarding the analgesic efficacy of supraclavicular block for shoulder surgery. This study aimed to compare the analgesic efficacy and side effects of interscalene and supraclavicular blocks for shoulder surgery.

METHODS

Patients scheduled for shoulder surgery were assigned to receive either ultrasound-guided interscalene (n = 25) or supraclavicular block (n = 24) with 20 ml of 0.375% ropivacaine. We assessed the duration of post-operative analgesia as a primary outcome and pain scores, supplemental analgesia, diaphragmatic excursion, motor block, fingertip numbness, side effects, and patient satisfaction as secondary outcomes.

RESULTS

The duration of post-operative analgesia was not statistically different between groups: 868 (800-1440) min for supraclavicular block vs. 800 (731-922) min for interscalene block (median difference -85 min, 95% CI, -283 to 3 min, P = 0.095). The incidence of diaphragmatic paresis was significantly lower in the supraclavicular block group compared with that in the interscalene block group, both at 30 min after the block (66.7% vs. 92%, P = 0.021) and in the post-anaesthesia care unit (62.5% vs. 92%, P = 0.024). Motor block was higher in the supraclavicular block group in the post-anaesthesia care unit, however, not at 24 h. Other secondary outcomes were similar for both groups.

CONCLUSIONS

This study showed no statistically significant difference in the duration of post-operative analgesia between the supraclavicular and interscalene blocks. However, the supraclavicular block was associated with a lower incidence of diaphragmatic paresis compared with that of the interscalene block after shoulder surgery.