Comparison of tissue distribution, phrenic nerve involvement, and epidural spread in standard- vs low-volume ultrasound-guided interscalene plexus block using contrast magnetic resonance imaging: a randomized, controlled trial

Just the facts: brachial plexus blocks for upper extremity injuries in the emergency department

Ultrasound-guided nerve blocks (UGNBs) are becoming a more common method for pain control in the emergency department. Specifically, brachial plexus blocks have shown promise for acute upper extremity injuries as well as an alternative to procedural sedation for glenohumeral reductions. Unfortunately, there is minimal discussion in the EM literature regarding phrenic nerve paralysis (a well-known complication from brachial plexus blocks). The anatomy of the brachial plexus, its relationship to the phrenic nerve, and why ultrasound-guided brachial plexus blocks can cause phrenic nerve paralysis and resultant respiratory impairment will be discussed. The focus on patient safety is paramount, and those with preexisting respiratory conditions, extremes of age or weight, spinal deformities, previous neck injuries, and anatomical variations are at greater risk. We put forth different block strategies for risk mitigation, including patient selection, volume and type of anesthetic, block location, postprocedural monitoring, and specific discharge instructions. Understanding the benefits and risks of UGNBs is critical for emergency physicians to provide effective pain control while ensuring optimal patient safety.

Continuous Interscalene Brachial Plexus Blocks: An Anatomical Challenge between Scylla and Charybdis?

Brachial plexus blocks at the interscalene level are frequently chosen by physicians and recommended by textbooks for providing regional anesthesia and analgesia to patients scheduled for shoulder surgery. Published data concerning interscalene single-injection or continuous brachial plexus blocks report good analgesic effects. The principle of interscalene catheters is to extend analgesia beyond the duration of the local anesthetic's effect through continuous infusion, as opposed to a single injection. However, in addition to the recognized beneficial effects of interscalene blocks, whether administered as a single injection or through a catheter, there have been reports of consequences ranging from minor side effects to severe, life-threatening complications. Both can be simply explained by direct mispuncture, as well as undesired local anesthetic spread or misplaced catheters. In particular, catheters pose a high risk when advanced or placed uncontrollably, a fact confirmed by reports of fatal outcomes. Secondary catheter dislocations explain side effects or loss of effectiveness that may occur hours or days after the initial correct function has been observed. From an anatomical and physiological perspective, this appears logical: the catheter tip must be placed near the plexus in an anatomically tight and confined space. Thus, the catheter's position may be altered with the movement of the neck or shoulder, e.g., during physiotherapy. The safe use of interscalene catheters is therefore a balance between high analgesia quality and the control of side effects and complications, much like the passage between Scylla and Charybdis. We are convinced that the anatomical basis crucial for the brachial plexus block procedure at the interscalene level is not sufficiently depicted in the common regional anesthesia literature or textbooks. We would like to provide a comprehensive anatomical survey of the lateral neck, with special attention paid to the safe placement of interscalene catheters.

A Randomized Comparison Between Interscalene and Combined Interscalene-Suprascapular Blocks for Arthroscopic Shoulder Surgery: A Prospective Clinical Study

Background

To compare the analgesic effect of ISB with a combination of ISB-SSNB and patients who were given opioids with PCA without block in adult patients undergoing shoulder surgery, as measured by opioid consumption and pain intensity in the first 24 hours postoperatively.

Methods

Ninety patients who underwent shoulder surgery were randomly divided into three groups. Group I in which ISB was performed and patient-controlled analgesia (PCA) was inserted, Group II with; ISB and SSNB combined, and PCA was inserted, and Group III where; only PCA was used. Visual analog scale (VAS) pain scores at the second, fourth, sixth, 12th, and 24th hours, morphine consumption, additional analgesic requirement, and patient satisfaction were evaluated.

Results

Compared with Group III, the VAS pain score was significantly lower in Group I and Group II at 2, 4, 6, 12, and 24 hours postoperatively. In Group I, the VAS score at rest at the 6th hour was found to be higher than in Group II. The 24-hour total morphine consumption was higher in the control group than in Group I and Group II. The satisfaction score of the control group was lower than Group I and Group II.

Conclusion

The combined application of ISB and SSNB block is beneficial in shoulder surgery to provide both intraoperative and postoperative analgesia and opioid consumption.

Level of Evidence

Level I; Randomized Controlled Trial; Treatment Study.

Comparison of shoulder anterior capsular block and interscalene brachial plexus block for shoulder arthroscopy: a preliminary analysis

BACKGROUND

This study aims to reveal the perioperative analgesic efficacy of a new technique, anterior capsular shoulder block, in treating pain after shoulder arthroscopy compared to the interscalene brachial plexus block.

METHODS

The study design is randomized, prospective, interventional, standardized and double-blind in the setting of orthopedic operating room and orthopedic postoperative ward. Forty patients between 18-90 years of age and with American Society of Anesthesiologists Physical Status classification I to III who received arthroscopic cuff repair surgery were randomized into two (1:1 distribution; N.=20) groups. The interventions were interscalene brachial plexus block for Group A and shoulder anterior capsular block for Group B. Primary measurements were pain scores within 48 hours. Secondarily total analgesia requirement, intraoperative heart rate and blood pressure, arthroscopic image quality were evaluated.

RESULTS

Pain scores within postoperative 48 hours were similar between SHAC and ISB groups with no significant difference (P>0.05). Total analgesia requirement, intraoperative and postoperative rescue analgesia, was also similar with no significance (P>0.05).

CONCLUSIONS

This study demonstrated that the anterior capsular shoulder block is an effective alternative with similar results to the interscalene brachial plexus block for managing pain after shoulder arthroscopy.

Clavipectoral fascia plane block spread: an anatomical study

BACKGROUND

The clavipectoral fascia plane block (CPB) is a novel anesthetic management strategy proposed by Valdes-Vilches for clavicle fractures. This study aimed to investigate the distribution of the injected solution around the clavicle and the surrounding tissues.

METHODS

Twelve clavicle samples were acquired from six cadavers. CPB was conducted using a 20 mL solution comprising methylene blue and iodinated contrast agent to improve visibility of the injected substance's dispersion. Methylene blue spread was assessed through anatomical dissection across distinct planes (subcutaneous, superficial muscular, deep muscular, and periosteal layers of the clavicle) in five cadavers. For the purpose of comparing methylene blue distribution, CT scans were performed on three cadavers.

RESULTS

Methylene blue was detected in the medial, intermediate, and lateral supraclavicular nerves, as well as superficial muscles including the deltoid, trapezius, sternocleidomastoid, and pectoralis major. However, no staining was observed in the deep muscle plane, including the subclavius, pectoralis minor, and clavipectoral fascia (CPF). Anterosuperior periosteum exhibited staining in 54% of surface, while only 4% of the posteroinferior surface. CT images displayed contrast staining in anterosuperior periclavicular region, consistent with observations from sagittal sections and anatomical dissections.

CONCLUSION

The CPB effectively distributes the administered solution in the anterosuperior region of the clavicular periosteum, superficial muscular plane, and supraclavicular nerves. However, it does not affect the posteroinferior region of the clavicular periosteum or the deep muscular plane, including the CPF.

An alternative approach for blocking the superior trunk of the brachial plexus evaluated by a single arm clinical trial

BACKGROUND

Interscalene brachial plexus block is associated with phrenic nerve paralysis. The objective of this study was to evaluate an alternative approach to interscalene brachial plexus blocks in terms of efficacy, grade of motor and sensory blockade, and phrenic nerve blockade.

METHODS

The study was prospective and interventional. The ten living patients studied were 18 to 65 years old, ASA physical status I or II, and submitted to correction of rotator cuff injury. A superior trunk blockade was performed at the superior trunk below the omohyoid muscle, without blocking the phrenic nerve. The needle was advanced below the prevertebral layer until contacting the superior trunk. In order to guarantee the correct positioning of the needle tip, an intracluster pattern of the spread was visualized. The block was performed with 5.ßmL of 0.5% bupivacaine in ten patients. In the six cadavers, 5.ßmL of methylene blue was injected. Diaphragmatic excursion was assessed by ultrasonography of the ipsilateral hemidiaphragm. In three patients, pulmonary ventilation was evaluated with impedance tomography. Pain scores and analgesic consumption were assessed in the recovery room for 6.ßhours after the blockade.

RESULTS

In the six cadavers, methylene blue didn...t reach the phrenic nerve. Ten patients underwent arthroscopic surgery, and no clinically phrenic nerve paralysis was observed. No patient reported pain during the first 6.ßhours.

CONCLUSIONS

This study suggests that this new superior trunk approach to block the superior trunk may be an alternative technique to promote analgesia for shoulder surgery in patients with impaired respiratory function.

The median effective analgesic concentration of ropivacaine in ultrasound-guided interscalene brachial plexus block after arthroscopic rotator cuff repair

Background: The median effective analgesic concentration (MEAC) of ropivacaine in interscalene brachial plexus block (ISBPB) for postoperative analgesia after arthroscopic rotator cuff repair (ARCR) has not been determined. Therefore, this study aimed to evaluate the MEAC after ARCR using 10 ml ropivacaine.

Method: This study was conducted on 40 patients with American Society of Anesthesiologists grade I or II who had selective ARCR. The 10 ml ropivacaine was administered for determined, with an initial concentration of 0.3% using up-and-down sequential allocation. After successful or unsuccessful postoperative analgesia, the concentration of ropivacaine was decreased or increased by 0.05% in the next patient. We defined successful postoperative analgesia as a visual analog scale score of <4 at rest within the initial 8 h after ISBPB. The analytic techniques of linear, linear-logarithmic, exponential regressions and centered isotonic regression were used for calculating MEAC. The secondary outcomes was sufentanil consumption, time to 1st rescue analgesic, onset time of sensory block and motor block.

Results: The concentration of ropivacaine administered ranged from 0.1% to 0.35%. The MEAC from the four different methods (linear, linear-logarithmic, exponential regressions and centered isotonic regression) were 0.207% (95% CI, 0.168–0.355%), 0.182% (95% CI, 0.165–0.353%), 0.196% (95% CI, 0.154–0.356%), and 0.163%, respectively. Of the four models, exponential regression had the least residual standard error (0.0990).

Conclusion: The MEAC derived from the four statistical models for 10 ml ropivacaine in ultrasound-guided ISBPB for postoperative analgesia was distributed within a narrow range of 0.163%–0.207%. The exponential regression model calculated by the goodness-of-fit test at a concentration of 0.196% best fits the study data.

Clinical Trial Registration:http://www.chictr.org.cn/showproj.aspx?proj=127449, identifier ChiCTR2100047978

A randomised controlled trial in patients undergoing arthroscopic shoulder surgery comparing interscalene block with either 10 ml or 20 ml levobupivacaine 0.25

The interscalene brachial plexus block is recommended for analgesia after shoulder surgery but it may cause hemidiaphragmatic dysfunction. We tested whether ipsilateral hemidiaphragmatic contraction was better after a smaller dose of local anaesthetic without impairing analgesic effect. We randomly allocated 48 adults to 10 ml or 20 ml levobupivacaine 0.25% before arthroscopic shoulder surgery. The primary outcome was hemidiaphragmatic paralysis, defined as inspiratory thickness < 1.2 times expiratory thickness, measured by ultrasound 4 h after block. Hemidiaphragmatic paralysis was recorded for 6/24 vs. 23/24 supine participants after 10 ml vs. 20 ml levobupivacaine 0.25%, respectively, and for 4/24 vs. 23/24 sitting participants, respectively, p < 0.001 for both. Pain scores after 10 ml injectate were not worse than after 20 ml injectate. Median (IQR [range]) morphine doses in the first 24 postoperative hours after 10 ml and 20 ml levobupivacaine 0.25% were 2 (0-6 [0-23]) mg vs. 1 (0-2 [0-11]) mg, respectively, p = 0.12. No participant had a complication after 10 ml interscalene levobupivacaine, whereas seven had complications after 20 ml levobupivacaine, p = 0.009. Hemidiaphragmatic function was better after 10 ml vs. 20 ml interscalene levobupivacaine 0.25% without impairing analgesia for 24 postoperative hours.

Combined thoracic paravertebral block and interscalene brachial plexus block for modified radical mastectomy: A case report

BACKGROUND

Modified radical mastectomy (MRM) is the most common surgical treatment for breast cancer. General anesthesia poses a challenge in fragile MRM patients, including cardiovascular instability, insufficient postoperative pain control, nausea and vomiting. Thoracic paravertebral block (TPVB) is adequate for simple mastectomy, but its combination with interscalene brachial plexus block (IBPB) has not yet been proved to be an effective anesthesia method for MRM.

CASE SUMMARY

We describe our experience of anesthesia and pain management in 10 patients with multiple comorbidities. An ultrasound-guided TPVB was placed at T2-T3 and T5-T6, and combined with IBPB, with administration of 10, 15 and 5 mL of 0.5% ropivacaine, respectively. A satisfactory anesthetic effect was proved by the absence of ipsilateral tactile sensation within 30 min. Propofol 3 mg/kg/h and oxygen supplementation via a nasal cannula were administered during surgery. None of the patients required additional narcotics, vasopressors, or conversion to general anesthesia. The maximum pain score was 2 on an 11-point numerical rating scale. Two patients required one dose of celecoxib 8 h postoperatively and none reported nausea or emesis.

CONCLUSION

This case series demonstrated that combined two-site TPVB and small-volume IBPB with sedation can be used as an alternative anesthetic modality for MRM, providing good postoperative analgesia.

Understanding fascial anatomy and interfascial communication: implications in regional anesthesia

With the extensive application of ultrasound in regional anesthesia, there has been rapid development of interfascial plane block techniques recently. Compared with neuraxial anesthesia or nerve plexus blocks, the interfascial plane blocks have many advantages, such as technical simplicity, fewer complications and comparable or better analgesia. The concept of fascial interconnectivity is fundamental in understanding the effects and complications of interfascial plane blocks. Many fascial planes are continuous and communicate with each other without a clear anatomical boundary. The prevertebral fascia of the neck, endothoracic fascia of the chest, transversalis fascia of the abdomen, and the fascia iliaca of the pelvic cavity form a natural fascial continuation. This anatomical feature suggests that the space beneath the cervical prevertebral fascia, the thoracic paravertebral space, the space between transversalis fascia and psoas muscles (psoas major and quadratus lumborum), and the fascia iliaca compartment are a confluent potential cavity. Additionally, the permeability of the fascia at different anatomical locations to local anesthetics is different, which can also influence the block effect and the incidence of complications. This article summarizes the anatomical characteristics and communication relationships of the major fascia which are related to regional anesthesia, and their relationships with block effects and complications.

Comparison Between Subparaneural Upper Trunk and Conventional Interscalene Blocks for Arthroscopic Shoulder Surgery: A Randomized Noninferiority Trial

BACKGROUND

Although interscalene nerve block is the standard for shoulder analgesia, the risk of hemidiaphragmatic paralysis restricts its use in patients with compromised pulmonary function. We hypothesized that a novel subparaneural upper trunk block would provide noninferior postoperative analgesia but superior diaphragmatic sparing effect compared to interscalene block.

METHODS

This randomized controlled trial comprised 96 patients who underwent arthroscopic shoulder surgery under either subparaneural upper trunk block (5 mL of 0.5% ropivacaine) or interscalene block (15 mL of 0.5% ropivacaine), followed by supraclavicular nerve block (5 mL of 0.5% ropivacaine). General anesthesia was standardized. The coprimary outcomes were (1) recovery room resting pain score at 30 minutes, measured on an 11-point numerical rating scale, with a prespecified noninferiority margin of 1 point and (2) the incidence of hemidiaphragmatic paralysis, diagnosed using ultrasound. Among secondary outcomes, resting pain scores were assessed with numerical rating scale at 4, 8, and 24 hours postoperatively.

RESULTS

Recovery room resting pain scores at 30 minutes were 0 (0-1) in the subparaneural upper trunk group versus 0 (0-0) in the interscalene group, with a median difference of 0 (95% CI, 0-0); the upper 95% CI limit was lower than the prespecified noninferiority margin (noninferiority P < .001). Hemidiaphragmatic paralysis was observed in 16.7% of patients in the subparaneural upper trunk group versus 100% of those in the interscalene group (RR, 0.17; 95% CI, 0.09-0.31; P < .001), with complete paralysis occurring in 6.3% and 93.7% of patients, respectively. In this study, any reported differences in pain scores at 4, 8, and 24 hours postoperatively were not clinically important.

CONCLUSIONS

The subparaneural upper trunk block compared to interscalene block provided noninferior analgesia at 30 minutes in the recovery room after arthroscopic shoulder surgery but resulted in less hemidiaphragmatic paralysis.

Depth of cervical plexus block and phrenic nerve blockade: a randomized trial

Background and objectives

Cervical plexus blocks are commonly used to facilitate carotid endarterectomy (CEA) in the awake patient. These blocks can be divided into superficial, intermediate, and deep blocks by their relation to the fasciae of the neck. We hypothesized that the depth of block would have a significant impact on phrenic nerve blockade and consequently hemi-diaphragmatic motion.

Methods

We enrolled 45 patients in an observer blinded randomized controlled trial, scheduled for elective, awake CEA. Patients received either deep, intermediate, or superficial cervical plexus blocks, using 20 mL of 0.5% ropivacaine mixed with an MRI contrast agent. Before and after placement of the block, transabdominal ultrasound measurements of diaphragmatic movement were performed. Patients underwent MRI of the neck to evaluate spread of the injectate, as well as lung function measurements. The primary outcome was ipsilateral difference of hemi-diaphragmatic motion during forced inspiration between study groups.

Results

Postoperatively, forced inspiration movement of the ipsilateral diaphragm (4.34±1.06, 3.86±1.24, 2.04±1.20 (mean in cm±SD for superficial, intermediate and deep, respectively)) was statistically different between block groups (p<0.001). Differences were also seen during normal inspiration. Lung function, oxygen saturation, complication rates, and patient satisfaction did not differ. MRI studies indicated pronounced permeation across the superficial fascia, but nevertheless easily distinguishable spread of injectate within the targeted compartments.

Conclusions

We studied the characteristics and side effects of cervical plexus blocks by depth of injection. Diaphragmatic dysfunction was most pronounced in the deep cervical plexus block group.

Trial registration number

EudraCT 2017-001300-30.

Analgesic comparison between perineural and intravenous dexamethasone for shoulder arthroscopy: a meta-analysis of randomized controlled trials

Introduction

The analgesic comparison between perineural and intravenous dexamethasone on interscalene block for pain management after shoulder arthroscopy remains controversial. We conduct this meta-analysis to explore the influence of perineural versus intravenous dexamethasone on interscalene block for pain control after shoulder arthroscopy.

Methods

We have searched PubMed, Embase, Web of science, EBSCO and Cochrane library databases through April 2021 and included randomized controlled trials (RCTs) assessing the effect of perineural and intravenous dexamethasone on interscalene block in patients with shoulder arthroscopy.

Results

Five RCTs were included in the meta-analysis. Overall, compared with intravenous dexamethasone for shoulder arthroscopy, perineural dexamethasone led to similar block duration (SMD = 0.12; 95% CI − 0.12 to 0.35; P = 0.33), pain scores at 12 h (SMD = − 0.67; 95% CI − 1.48 to 0.15; P = 0.11), pain scores at 24 h (SMD = − 0.33; 95% CI − 0.79 to 0.14; P = 0.17), opioid consumption (SMD = 0.01; 95% CI − 0.18 to 0.19; P = 0.95) and incidence of nausea/vomiting (OR = 0.74; 95% CI 0.38–1.44; P = 0.38).

Conclusions

Perineural and intravenous dexamethasone demonstrated comparable pain relief after shoulder arthroscopy.

Intravenous versus perineural dexmedetomidine in prolongation of analgesia with regional anesthesia: a meta-analysis and systematic review

Background and Objective. It is unclear whether perineural administration offers advantages when compared to intravenous dexmedetomidine in local anesthesia. To compare the efficacy of perineural versus intravenous dexmedetomidine as local anesthetic adjuvant, we conducted the meta analysis and systematic review. Materials and Methods. Two researchers searched MEDLINE, OVID, PubMed, Embase, Cochrane Central, Web of Science and Wanfang data for randomized controlled trials comparing the effect of intravenous versus perineural dexmedetomidine as local anesthetic adjuvant without any language restrictions. Results. We identified 14 randomized controlled trials (801 patients). The results revealed that the duration of analgesia (SMD: -1.76, 95 % CI, [-2.7, -0.83] P = 0.000, I2 = 96 %), the duration of sensory block (SMD:- 3.99, 95 % CI, [-5.88, -2.0], P = 0.000, I2 = 97.6 %), the duration of motor block (SMD: -1.6, 95 % CI, [-2.78, -0.41] P = 0.008, I 2 = 95.5 %) were significantly longer in the perineural group, when compared to systematic dexmedetomidine. The onset time of sensory block (SMD: 1.55, 95 % CI, [0.16, 2.94] P = 0.028, I2 = 96.7 %) and the onset time of motor block (SMD: 0.84, 95 % CI, [0.17, 1.5] P = 0.013, I2 = 88.3 %) were shorter in perineural group compared to intrave nous dexmedetomidine. Meanwhile, analgesic consumption in 24 hours (SMD: 0.37, 95 % CI, [0.05, 0.69] P = 0.023, I 2 = 55.6 %) and the incidence of patients of Ramsay Sedation Scale > 3 (RR: 3.8, 95 % CI, [1.45, 9.97] P = 0.000, I 2 = 26.9 %), hypotension (RR: 1.74, 95 % CI, [1.15, 2.65] P= 0.009, I2 = 32.7 %) and bradycardia (RR: 3.71, 95 % CI, [1.27, 10.86] P = 0.017, I2 = 0 %) were lower in perineural dexmedetomidine compared to the intravenous group. Conclusions. Our meta-analysis generates the evidence that perineural dexmedetomidine is a superior adminstration for prolonging the duration of analgesia. Perineural dexmedetomidine also shows the advantages in duration of sensory block and the onset time of sensory and motor block, when compared to the intravenous administration. Simultaneously, dexmedetomidine as a local anesthetic adjuvant for perineural injection may be much safer than intravenous application because of the lower incidence of patients of Ramsay Sedation Scale > 3 and lower incidence of hypotension and bradycardia.

Can saline injection protect phrenic nerve? - A randomised controlled study

Background and Aims

Various methods were attempted to reduce the incidence of phrenic nerve palsy during interscalene brachial plexus nerve block. Mechanism of phrenic palsy was presumed to be due to the spread of local anaesthetic anterior to the anterior scalene muscle. We hypothesised that by injecting saline in this anatomical location prior to performing an interscalene block might reduce the incidence of phrenic palsy.

Methods

This was a double-blinded randomised controlled study performed in a single-centre, university-teaching hospital. A total of 36 patients were randomised to either group C (conventional group) or group S (saline group). Ultrasound-guided interscalene block was administered with 20 ml of 0.25% levo-bupivacaine in both groups. Ten ml of normal saline was injected anterior to anterior scalene muscle in group S prior to performing interscalene block. A blinded radiologist performed diaphragmatic ultrasound pre- and post-operatively to document phrenic palsy. Bedside spirometry was used to perform baseline and post-operative pulmonary function test. The primary outcome was to look at the incidence of phrenic palsy as measured by diaphragmatic palsy on ultrasound performed by radiologist. Statistical Package for the Social Sciences (SPSS) version 25 was used for statistical analysis.

Results

Significantly less patients in the saline group developed diaphragmatic paresis when compared to conventional group (44% vs. 94%, Chi-squared = 10.01, P = 0.002). There was no difference in post-operative pain, subjective sensation of dyspnoea or patient satisfaction between the groups.

Conclusion

Injecting saline anterior to anterior scalene muscle reduces the incidence of diaphragmatic palsy when performing interscalene block.

Effects of Local Anesthetic Volume (Standard Versus Low) on Incidence of Hemidiaphragmatic Paralysis and Analgesic Quality for Ultrasound-Guided Superior Trunk Block After Arthroscopic Shoulder Surgery

BACKGROUND

Relative to interscalene block, superior trunk block (STB) provides comparable analgesia and a reduced risk of hemidiaphragmatic paralysis. However, the incidence of hemidiaphragmatic paralysis remains high when a standard volume (15 mL) of local anesthetic is used. This study aimed to evaluate the effects of local anesthetic volume of STB on the incidence of phrenic nerve palsy, as well as its analgesic efficacy following arthroscopic shoulder surgery.

METHODS

Patients scheduled for elective arthroscopic shoulder surgery were randomized to receive ultrasound-guided STB using either 5- or 15-mL 0.5% ropivacaine before general anesthesia. The primary outcome was the incidence of hemidiaphragmatic paralysis at 30 minutes after block. The secondary outcomes were pulmonary function, grade of sensory and motor blockade, pain score, opioid consumption, adverse effects, and satisfaction.

RESULTS

Relative to standard-volume STB, low-volume STB was associated with a lower incidence of hemidiaphragmatic paralysis after block (14.3 [4.8%-30.3%] vs 65.7 [46.8%-80.9%]; difference 51.4% [95% confidence intervals {CIs}, 29.0%-67.1%]; P < .0001) and at the postanesthesia care unit (9.4% vs 50.0%; difference 40.6 [95% CI, 18.9%-57.7%]; P = .0004). Pulmonary function was also better preserved in the low-volume group than in the standard-volume group. The extent of the sensory and motor blocks was significantly different between the groups. Pain-related outcomes, satisfaction, and any adverse events were not significantly different between the groups.

CONCLUSIONS

Low-volume STB provided a lower incidence of hemidiaphragmatic paralysis with no significant difference in analgesic efficacy relative to standard-volume STB for arthroscopic shoulder surgery.

Diaphragmatic paralysis, respiratory function, and postoperative pain after interscalene brachial plexus block with a reduced dose of 10 ml levobupivacaine 0.25% versus a 20 ml dose in patients undergoing arthroscopic shoulder surgery: study protocol for the randomized controlled double-blind REDOLEV study

Background

Arthroscopic shoulder surgery causes severe postoperative pain. An interscalene brachial plexus block provides adequate analgesia, but unintended spread of the local anesthetic administered may result in a phrenic nerve block, usually associated with a nonnegligible incidence of acute hemidiaphragmatic paralysis.

The main purpose of this trial will be to analyze the incidence of hemidiaphragmatic paralysis ensuing after interscalene brachial plexus block in patients undergoing arthroscopic shoulder surgery administered a standard volume (20 ml) vs. a low volume (10 ml) of levobupivacaine 0.25%.

Methods

This will be a prospective double-blind randomized controlled single-center two-arm comparative trial. Forty-eight patients will be included. The primary goal will be to ultrasonographically determine the incidence of hemidiaphragmatic paralysis by calculating the diaphragmatic thickness ratio in each group. The secondary goals will be to compare the two arms in terms of (1) decrease in forced vital capacity and (2) in forced expiratory volume at 1 s by spirometry; (3) decrease in diaphragmatic excursion by ultrasound; (4) 24-h total intravenous morphine consumption; (5) time to first opioid request of a patient-controlled analgesia pump; and (6) postoperative complications.

Discussion

This trial will demonstrate that a low-volume interscalene brachial plexus block decreases hemidiaphragmatic paralysis following arthroscopic shoulder surgery according to spirometry and ultrasound measurements and does not provide inferior postoperative analgesia to the standard volume, as measured by opioid requirements.

Trial registration

EudraCT and Spanish Trial Register (REec) registration number: 2019-003855-12 (registered on 7 January 2020). ClinicalTrials.gov identification number: NCT04385966 (retrospectively registered on 8 May 2020). Ethics Committee approval: EC19/093 (18 December 2019).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05216-6.

C5 ventral ramus block for clavicle surgery: How low concerning the volume can we go?

Background and Aims:

Clinical case reports mention 3-5 ml of local anesthetic (LA) at the cervical root 5 (C5) for surgical anesthesia essential for clavicle surgeries with reasonable success. A volume of 5 ml LA has been shown to cause hemidiaphragmatic paresis.

Material and Methods:

We implement the 3–5 ml LA for awake clavicle surgeries along with a supraclavicular nerve (SCN) block with another 2 ml. To understand the spread of injectate, we conducted anatomic macroscopic dissection on Theil based cadavers. Post ultrasound injection of 3 ml of blue latex in one cadaver and green latex in the other, we dissected one cadaver and the other cadaver underwent a cross-section.

Results:

Dissection confirmed a vertical spread of dye more caudad than cephalad. There was no neuraxial spread visualized in the cross-section. The phrenic nerve (PN) was not stained in both cadavers, but a possibility exists depending on its course.

Conclusion:

Based on this limited study we recommend a volume of LA of 3 ml at the level of C5 and another 2 ml at the level SCN of LA for clavicle surgeries.

Low-volume C5–6 interscalene and supraclavicular nerve blocks for arthroscopic shoulder surgery: A case series

Interscalene block (ISB) is considered a gold standard regional anesthesia technique for shoulder surgery. Conventionally, 20 ml of local anesthetic is used for ISB. Nevertheless, this high-volume traditional ISB is associated with a high incidence of hemidiaphragmatic paresis due to phrenic nerve block. Recent evidence suggests that low-volume ultrasound-guided (USG)-ISB can provide effective analgesia whilst avoiding complications. Thirty patients of American Society of Anaesthesiologist ASA status I/II undergoing arthroscopic rotator cuff repair surgery under general anesthesia were administered low-volume USG-ISB and supraclavicular nerve block (SCNB). The block provided effective analgesia in 90% (27/30) of the patients as their visual analog score was below 4 at all times in the 24-h postoperative period. Only three patients required a single dose of rescue analgesic (diclofenac 50 mg iv) in the 24-h postoperative period. In postoperative recovery, two patients (6.67%) had desaturation due to hemidiaphragmatic paresis and three patients (10%) had a transient neurological deficit. In conclusion, low-volume USG-ISB with SCNB provides effective analgesia for arthroscopic rotator cuff repair surgery. The advantages of this technique include a low incidence of respiratory and neurological complications.

Dose-response relationship between local anesthetic volume and hemidiaphragmatic paresis following ultrasound-guided supraclavicular brachial plexus blockade

BACKGROUND

There is no consensus regarding what volume of local anesthetic should be used to achieve successful supraclavicular block while minimizing hemidiaphragmatic paresis (HDP). This study investigated the dose-response relationship between local anesthetic volume and HDP after ultrasound-guided supraclavicular brachial plexus block.

METHODS

A dose escalation design was used to define the dose response curve for local anesthetic volume and incidence of HDP in subjects undergoing upper extremity surgery with supraclavicular block as the primary anesthetic. Dosing levels of 5, 10, 15, 20, 25, 30, 35 and 40 mL of local anesthetic were administered in cohorts of three subjects per dose. Diaphragm function was assessed with M-mode ultrasound before and after block. Secondary objectives included assessment of negative inspiratory force (NIF), oxygen saturation, subjective dyspnea and extent of sensory and motor blockade.

RESULTS

Twenty-one subjects completed the study. HDP was present at all doses, with an incidence of 33% at 5 mL to 100% at 30-35 mL. There was a significant decrease in NIF (7.5 cmH₂O, IQR (22,0); p=0.01) and oxygen saturation on room air (1%, IQR (2,0); p=0.01) 30 min postblock in subjects experiencing HDP but not in those without HDP. There was no increase in dyspnea in subjects with or without HDP. No subject required respiratory intervention. Motor and sensory block improved with increasing dose, and subjects with HDP exhibited denser blocks than those without (p<0.01).

CONCLUSIONS

There is no clinically relevant volume of local anesthetic at which HDP can be avoided when performing a supraclavicular block. In our subject population free of respiratory disease, HDP was well tolerated.

TRIAL REGISTRATION NUMBER

NCT03138577.

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.

Costoclavicular brachial plexus block reduces hemidiaphragmatic paralysis more than supraclavicular brachial plexus block: retrospective, propensity score matched cohort study

Background

Hemidiaphragmatic paralysis, a frequent complication of the brachial plexus block performed above the clavicle, is rarely associated with an infraclavicular approach. The costoclavicular brachial plexus block is emerging as a promising infraclavicular approach. However, it may increase the risk of hemidiaphragmatic paralysis because the proximity to the phrenic nerve is greater than in the classical infraclavicular approach.

Methods

This retrospective analysis compared the incidence of hemidiaphragmatic paralysis in patients undergoing costoclavicular and supraclavicular brachial plexus blocks. Of 315 patients who underwent brachial plexus block performed by a single anesthesiologist, 118 underwent costoclavicular, and 197 underwent supraclavicular brachial plexus block. Propensity score matching selected 118 pairs of patients. The primary outcome was the incidence of hemidiaphragmatic paralysis, defined as a postoperative elevation of the hemidiaphragm > 20 mm. Factors affecting the incidence of hemidiaphragmatic paralysis were also evaluated.

Results

Hemidiaphragmatic paralysis was observed in three patients (2.5%) who underwent costoclavicular and 47 (39.8%) who underwent supraclavicular brachial plexus blocks (P < 0.001; odds ratio, 0.04; 95% confidence interval, 0.01-0.13). Both the brachial plexus block approach and the injected volume of local anesthetic were significantly associated with hemidiaphragmatic paralysis.

Conclusions

The incidence of hemidiaphragmatic paralysis is significantly lower with costoclavicular than with supraclavicular brachial plexus block.

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%.

Diaphragm-sparing effect of the infraclavicular subomohyoid block vs low volume interscalene block. A randomized blinded study

BACKGROUND

Both low volume interscalene and infraclavicular-subomohyoid blocks were suggested to provide shoulder analgesia with low risk of phrenic nerve block. The aim of this study was to compare the frequency of the phrenic nerve block between these two techniques.

METHOD

Seventy-two patients scheduled for shoulder arthroscopy were included in this randomized controlled blind study. Before induction of general anesthesia, patients received low volume interscalene block using 5 mL of ropivacaine 0.5% (LVS group) or infraclavicular-subomohyoid block using 25 mL of ropivacaine 0.5% (ISO group). The diaphragmatic excursion was measured (using ultrasound) before the block and after surgery. If the ratio of postoperative to pre-block excursions was <25%, a phrenic nerve block was concluded. Secondary outcomes were: the duration of analgesia, the 24-hour morphine requirement, and patient satisfaction.

RESULTS

The phrenic nerve was blocked in 88.9% of patients in LVS group vs 5.6% in ISO group (P < 0.001). There was no significant difference between the two groups with regard to the duration of analgesia, the morphine consumption, and the patient satisfaction.

CONCLUSION

Compared with the low volume interscalene block, the infraclavicular subomohyoid block resulted in a significantly less frequent phrenic nerve block and with no difference in postoperative analgesia. Therefore, it may be relevant to consider for patients who cannot tolerate a phrenic nerve block.

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.

Weakness of contralateral upper limb after interscalene block - A case report

We have reported a case of right upper limb injury of shoulder and elbow who was managed with ultrasound-guided interscalene block during surgery and indwelling catheter for postoperative analgesia. He developed weakness in the contralateral upper limb in the postoperative period due to inadvertent spread of local anaesthetic in the cervical epidural space. No serious complication occurred due to timely intervention. The possible pathways of such unwanted epidural spread and methods to reduce such complications have been discussed.

Regional anesthesia to ameliorate postoperative analgesia outcomes in pediatric surgical patients: an updated systematic review of randomized controlled trials

Regional anesthesia is becoming increasingly popular among anesthesiologists in the management of postoperative analgesia following pediatric surgery. The main objective of this review was to systematically evaluate the last 5 years of randomized controlled trials on the role of regional anesthesia techniques in alleviating postoperative pain associated with various pediatric surgical procedures. Forty studies on 2,408 pediatric patients were evaluated. The majority of the articles published from 2013 to 2017 reported that the use of regional anesthesia minimized postoperative pain and reduced opioid consumption. Only a few surgical procedures (cholecystectomy, inguinal hernia repair, and non-laparoscopic major abdominal surgery) reported no significant difference in the postoperative pain relief compared with the standard anesthetic management. The growing number of randomized controlled trials in the pediatric literature is very promising; however, additional confirmation is needed to reinforce the use of specific regional anesthesia techniques to provide optimal postoperative pain relief for a few surgical procedures (reconstructive ear surgery, chest wall deformity, hypospadias, umbilical hernia, cleft palate repair) in pediatric patients. More randomized controlled trials are needed to establish regional anesthesia as an essential component of postoperative analgesia management in children.

Supraclavicular Brachial Plexus Neurolysis for a Malignant Peripheral Nerve Sheath Tumor: A Case Report

The perineural administration of alcohol or phenol results in protein denaturation and, consequently, neurolysis. This can produce long-lasting analgesia, with a duration of 3-6 months. Although neurolytic blocks for the brachial plexus have been described in multiple review articles and textbooks, they are rarely performed. As such, little is known about the efficacy and adverse effect profile of this commonly described treatment. In this article, we report the outcomes of a patient who underwent a left brachial plexus neurolytic block for the management of upper limb pain arising from a malignant peripheral nerve sheath tumor.

Effects of Stellate Ganglion Block on Analgesia Produced by Cervical Paravertebral Block as Established by Quantitative Sensory Testing: A Randomized Controlled Trial

Objective

To use quantitative sensory testing (QST) to assess whether a stellate ganglion block (SGB) modulates the analgesia induced by cervical paravertebral block (CPVB).

Design

A prospective double-blind randomized controlled trial.

Setting

Department of Anesthesia, Antwerp University Hospital, October 2011 to December 2015.

Subjects

Twenty-eight adults scheduled for arthroscopy of a nonfractured shoulder were enrolled.

Methods

Participants were randomly assigned to receive either single CPVB (5 mL of levobupivacaine 0.5%) or combined CPVB + SGB (5 mL and 3 mL of levobubivacaine 0.5%, respectively). The detection thresholds for cold/warm sensations and cold/heat pain were established using thermal QST on the C4-C7 dermatomes before local anesthetic infiltration and at 0.5, 6, 10, and 24 hours thereafter. Our primary outcome was the time course of QST thresholds for the different neurosensitive/nociceptive modalities. As secondary and tertiary outcomes, we evaluated the degree of motor block and the time to first administration of rescue analgesics.

Results

We randomized 20 patients. There were no significant differences in the detection thresholds for the neurosensitive/nociceptive modalities, motor block, or timing for rescue analgesics between the groups (P = 0.15-0.94). All patients with CPVB + SGB exhibited Horner's signs, whereas patients in the CPVB group did not exhibit these signs; however, this does not exclude sympathetic block.

Conclusions

We were unable to demonstrate any analgesic benefit of CPVB + SGB in arthroscopic shoulder surgery. It is therefore not unreasonable to suppose that pain from soft tissue injuries without bony lesions is transmitted mainly by somatic nerves with no or only minimal involvement of the sympathetic nervous system.

Management of residual pleural space after lung resection: fully controllable paralysis of the diaphragm through continuous phrenic nerve block

Background

Residual pleural space after lung resection associated with air leak is a challenging issue, potentially causing serious complications. We report a new, postoperative technique to reduce the pleural space, inducing a controlled and reversible paralysis of the diaphragm.

Methods

Ten patients were enrolled (7 lobectomies, 2 bilobectomy, 1 wedge resection). Inclusion criteria were: digitally detected air flow >200 mL/min at post-op day 3, presence of empty pleural space at chest x-ray, absence of restrictive lung disease, absence of known arrhythmias. A 22G nerve-block catheter was place under ultrasound guidance in proximity to the phrenic nerve, between the sternocleidomastoid muscle and the anterior scalene muscle at the level of 6^th cervical vertebra. Continuous infusion of ropivacaine 0.2% 3 mL/h was started. Fluoroscopy was used to confirm significant reduction in hemidiaphragm movements. Monitoring of vital signs and intense respiratory physiotherapy were enhanced. The infusion was stopped at air leak cessation and the catheter was removed along with the chest drain.

Results

No peri- and post-procedural complications occurred. In all patients, we observed an immediate reduction of the empty pleural space and resolution of the air leak within few days (3±1.16 days). After suspension of local anaesthetic, complete restoration of the hemidiaphragm function has been documented.

Conclusions

This is an effective and minimally invasive method to reduce the residual pleural space after lung resections. Narrowing of the pleural space facilitates the contact between the lung and the chest wall promoting the resolution of the air leak. Diaphragm paralysis is controlled and temporary with no residual disabilities.

A Systematic Review of Postoperative Pain Outcome Measurements Utilised in Regional Anesthesia Randomized Controlled Trials

INTRODUCTION

Regional anesthesia is a rapidly growing subspecialty. There are few published meta-analyses exploring pain outcome measures utilised in regional anesthesia randomized controlled trials (RCTs), which may be due to heterogeneity in outcomes assessed. This systematic review explores postoperative pain outcomes utilised in regional anesthesia RCTs.

METHODS

A literature search was performed using three databases (Medline, Embase, and CINAHL). Regional anesthesia RCTs with postoperative pain as a primary outcome were included if written in English and published in one of the top 20 impact factor journals between 2005 and 2017. Study quality was assessed using the Cochrane Collaboration's tool for assessing risk of bias.

RESULTS

From the 31 included articles, 15 different outcome measures in total were used to assess postoperative pain. The most commonly (16/31) used outcome measures were verbal numerical grading of pain out of 10, total opioid consumption, and visual analogue scale 10 cm (VAS). The need for analgesia was used as an outcome measure where studies did not use a pain rating score. Ten studies reported pain scores on activity and 27/31 studies utilised ≥2 pain outcomes. Time of measurement of pain score also varied with a total of 51 different time points used in total.

CONCLUSION

Analysis of the articles demonstrated heterogeneity and inconsistency in choice of pain outcome and time of measurement within regional anesthesia studies. Identification of these pain outcomes utilised can help to create a definitive list of core outcomes, which may guide future researchers when designing such studies.

Hemidiaphragmatic paralysis: A case report

Hemidiaphragmatic paralysis is initially recognised as postoperative respiratory distress. The subsequent sequential management of the patient following arthroscopic shoulder surgery under interscalene block is described. Ultrasound-guided technique is considered to be the safest for interscalene block. Reducing the volume of anaesthetic used reduces its spread to the phrenic nerve and thus reduces the incidence of hemidiaphragmatic paralysis. Furthermore, a reduction in anaesthetic volume has equivalent analgesic efficacy.

A randomized trial of automated intermittent ropivacaine administration vs. continuous infusion in an interscalene catheter

BACKGROUND

Ultrasound-guided interscalene nerve block with ropivacaine as local anesthetic agent given as boluses or continuous infusion is the preferred pain management after major shoulder surgery. The use of automated intermittent boluses has been shown to be superior to continuous infusion in sciatic and epidural nerve block.

HYPOTHESIS

Automated intermittent boluses reduce pain after major shoulder surgery.

METHODS

Seventy patients aged 18-75 years, scheduled for major shoulder surgery under general anesthesia with interscalene nerve block were included in this randomized controlled trial. Patients were allocated to either automated intermittent boluses with 16 mg ropivacaine every 2 h combined with patient-controlled administration or to a conventional regimen of continuous infusion of 8 mg/h (4 ml/h) of ropivacaine combined with patient controlled administration (2 ml, lockout time 30 min). Pain (Visual Analog Scale, VAS) was assessed every 8 h postoperatively.

RESULTS

Fifty-seven patients completed the study, 29 in the continuous infusion group and 28 in the automated intermittent bolus group. Shoulder arthroplasty was performed in 49 (86%) of the cases. There were no significant differences in VAS score from 8 to 48 h post-operatively. No significant difference in opioid usage was observed. The automated intermittent bolus group reported significantly less force on coughing and more hoarseness. A significantly lower volume of ropivacaine was used in the automated intermittent bolus group.

CONCLUSION

Automated intermittent boluses did not reduce pain or rescue opioid consumption compared with continuous infusion of ropivacaine. The automated intermittent bolus group had significantly less force on coughing and more hoarseness.

Ultrasound-Guided Interscalene Brachial Plexus Nerve Block With an Ultralow Volume of Local Anesthetic for Post-Thoracotomy Shoulder Girdle Pain

OBJECTIVES

To evaluate the efficacy of ultrasound-guided interscalene nerve block using an ultralow volume of local anesthetic (5 mL of ropivacaine, 0.75%) for the management of post-thoracotomy shoulder girdle pain.

DESIGN

Open-cohort, prospective, single-center study.

SETTING

University hospital.

INTERVENTIONS

Patients with post-thoracotomy shoulder girdle pain (visual analog scale [VAS] ≥5) received an ultrasound-guided interscalene nerve block.

MEASUREMENTS AND MAIN RESULTS

Thirty minutes after block implementation, the VAS was used to quantify pain across the shoulder girdle. The index (I) was calculated to indicate improvement of pain as follows: [Formula: see text] Nerve bocks resulting in I ≥75% were considered excellent. Total tramadol consumption 36 hours after nerve blocks, patients' satisfaction, and complications related to the procedure also were assessed. Patients were segregated in the following 2 groups: group A, which comprised patients with pain in the shoulder area (glenohumeral and acromioclavicular joints) (n = 30), and group B, which comprised patients with pain in the scapula (n = 17). I was significantly greater in group A (88.3% ± 14%) than in group B (43.2% ± 22%). In groups A and B, 90% and 11% of patients, respectively, demonstrated excellent pain control. Total tramadol consumption in group A, 25 (0-100) mg, was significantly less that of group B, 250 (150-500) mg. Patients' satisfaction also was significantly higher in group A compared with group B. No complications were recorded.

CONCLUSIONS

Ultrasound-guided interscalene nerve block can substantially alleviate post-thoracotomy pain in the shoulder but not in the scapular area.

Continuous versus single shot brachial plexus block and their relationship to discharge barriers and length of stay

BACKGROUND

Brachial plexus block has been associated with improved pain control and decreased length of stay in patients undergoing upper extremity arthroplasty. Continuous delivery is associated with a shorter length of stay; however, comparisons to single-shot delivery in this setting are scarce. As the paradigm shifts to outpatient arthroplasty in the era of bundled payments, there exists a strong impetus to identify the most effective mode of analgesia associated with the least risk to patients.

METHODS

This is a retrospective review of 697 patients undergoing upper extremity arthroplasty comparing the rate of complications and incidence of potential barriers to discharge and length of stay of patients receiving continuous vs. single-shot perineural brachial plexus block.

RESULTS

No difference was observed in the complication rate between indwelling (n = 63 [12%]) and single-shot groups (n = 30 [17%]; P = .137). The majority of complications were pulmonary, 72% attributable to oxygen desaturation. The indwelling catheter group had 1.61 times higher odds (95% confidence interval, 1.07-2.42; P = .023) of exhibiting any potential barrier to discharge and exhibited a longer length of stay (P = .002).

CONCLUSION

There was no demonstrated disparity in the rate of complications associated with single-shot vs. continuous brachial plexus block. However, the continuous indwelling catheter was associated with an increased incidence of potential barriers to discharge and an increased length of stay compared with patients receiving single-shot regional anesthesia.

The Utility of Peripheral Nerve Blocks in Interventional Radiology

OBJECTIVE

The aim of this article is to provide an overview of peripheral nerve blocks, the use of peripheral nerve block within and outside interventional radiology, and the complications of peripheral nerve block.

CONCLUSION

Interventional radiologists are often responsible for sedation and pain management in the majority of interventional radiology procedures. Peripheral nerve block is increasingly being used in interventional radiology.

Upper extremity nerve block: how can benefit, duration, and safety be improved? An update

Upper extremity blocks are useful as both sole anaesthesia and/or a supplement to general anaesthesia and they further provide effective postoperative analgesia, reducing the need for opioid analgesics. There is without doubt a renewed interest among anaesthesiologists in the interscalene, supraclavicular, infraclavicular, and axillary plexus blocks with the increasing use of ultrasound guidance. The ultrasound-guided technique visualising the needle tip and solution injected reduces the risk of side effects, accidental intravascular injection, and possibly also trauma to surrounding tissues. The ultrasound technique has also reduced the volume needed in order to gain effective block. Still, single-shot plexus block, although it produces effective anaesthesia, has a limited duration of postoperative analgesia and a number of adjuncts have been tested in order to prolong analgesia duration. The addition of steroids, midazolam, clonidine, dexmedetomidine, and buprenorphine has been studied, all being off-label when administered by perineural injection, and the potential neurotoxicity needs further study. The use of perineural catheters is an effective option to improve and prolong the postoperative analgesic effect.

Upper extremity plexus blocks have an obvious place as a sole anaesthetic technique or as a powerful complement to general anaesthesia, reducing the need for analgesics and hypnotics intraoperatively, and provide effective early postoperative pain relief. Continuous perineural infusion is an effective option to prolong the effects and improve postoperative quality.