Reduced Hemidiaphragmatic Paresis With a "Corner Pocket" Technique for Supraclavicular Brachial Plexus Block: Single-Center, Observer-Blinded, Randomized Controlled Trial

Median effective volume of 0.2% ropivacaine for ultrasound-guided supraclavicular brachial plexus block in children aged 1-6 years: a prospective dose-finding study

Objective

To determine the median effective volume (EV₅₀) of 0.2% ropivacaine for ultrasound-guided supraclavicular brachial plexus block (SC-BPB) in children aged 1-6 years.

Methods

Children aged from 1 to 6 years with an American Society of Anaesthesiologists (ASA) physical status I-II who were scheduled for unilateral upper extremity surgery at the Children's Hospital of Chongqing Medical University were recruited. All patients underwent surgery under general anaesthesia combined with brachial plexus block. SC-BPB was guided by ultrasound after anaesthesia induction, and 0.2% ropivacaine was given after localization. In the study, we used Dixon's up-and-down approach with an initial dose of 0.50 ml/kg. Considering the effect of the previous block, a successful or failed block could produce a 0.05 ml/kg decrement or increment in volume, correspondingly. The experiment was stopped when there were 7 inflection points. Using isotonic regression and bootstrapping algorithms, the EV₅₀, the 95% effective volume (EV₉₅) and the 95% confidence interval (CI) were calculated. The patients' general information, postoperative pain scores, and adverse events were also recorded.

Results

Twenty-seven patients were involved in this study. The EV₅₀ of 0.2% ropivacaine was 0.150 ml/kg (95% CI, 0.131-0.169 ml/kg) and the EV₉₅ (secondary metric) was 0.195 ml/kg (95% CI, 0.188-0.197 ml/kg). No adverse events occurred during the research study.

Conclusions

For ultrasound-guided SC-BPB in children aged 1-6 years undergoing unilateral upper extremity surgery, the EV₅₀ of 0.2% ropivacaine was 0.150 ml/kg (95% CI, 0.131-0.169 ml/kg).

Impact of an extrafascial versus intrafascial injection for supraclavicular brachial plexus block on respiratory function: a randomized, controlled, double-blind trial

Introduction

Hemidiaphragmatic paresis after ultrasound-guided supraclavicular brachial plexus block is reported to occur in up to 67% of patients. We tested the hypothesis that an injection outside the brachial plexus sheath reduces the incidence of hemidiaphragmatic paresis compared with an intrafascial injection while providing similar analgesia.

Methods

Fifty American Society of Anesthesiologists I–III patients scheduled for elective upper limb surgery received a supraclavicular brachial plexus block using 30 mL of 1:1 mixture of mepivacaine 1% and ropivacaine 0.5%. The block procedures were randomized to position the needle tip either within the brachial plexus after piercing the sheath (intrafascial injection) or outside the brachial plexus sheath (extrafascial injection). The primary outcome was the incidence of hemidiaphragmatic paresis 30 min after the injection, measured by M-mode ultrasonography. Additional outcomes included time to surgery readiness, and resting and dynamic pain scores at 24 hours postoperatively (Numeric Rating Scale, 0–10).

Results

The incidence of hemidiaphragmatic paresis 30 min after the injection was 9% (95% CI 1% to 29%) and 0% (95% CI 0% to 15%) in the intrafascial and extrafascial groups respectively (p=0.14). Extrafascial injection was associated with a longer time to surgery readiness (intrafascial: 18 min (95% CI: 16 to 21 min); extrafascial: 37 min (95% CI: 31 to 42 min); p<0.001). At 24 hours, resting and dynamic pain scores were similar between groups.

Discussion

Ultrasound-guided supraclavicular brachial plexus block with an extrafascial injection does not reduce the incidence of hemidiaphragmatic paresis although it provides similar analgesia, when compared with an intrafascial injection. The longer time to surgery readiness is less compatible with contemporary operating theater efficiency requirements.

Trial registration number

NCT03957772.

Effects of Unilateral Intermediate Cervical Plexus Block on the Diaphragmatic Function in Patients Undergoing Unilateral Thyroidectomy: A Randomized Controlled Study

Background and Purpose

Although unilateral intermediate cervical plexus block (ICPB) can be used for perioperative analgesia in neck surgery, its effect on diaphragm function remains controversial. This prospective study aimed to examine whether unilateral ICPB with different concentrations of ropivacaine resulted in the diaphragmatic dysfunction in unilateral thyroidectomy.

Methods

A total of 54 patients scheduled to undergo unilateral thyroidectomy under general anesthesia were randomly allocated to receive either 10 mL of 0.3% (Group L) or 0.5% (Group H) ropivacaine for ICPB. General anesthesia was then administered for surgery. The diaphragm thickness and diaphragmatic excursion were measured at three different times: before the ICPB, at 40 min and 4 h after the block. The primary outcome was the incidence of diaphragmatic dysfunction of the block side at 40 min and 4 h after ICPB. Secondary outcomes included the maximum pain score within 24 h after the surgery, rescue analgesics within 24 h after the surgery, and time to first ambulation.

Results

The incidence of diaphragmatic dysfunction on the block side of Group H was higher than that of Group L at 40 min after block (58% vs 29%, P = 0.01). However, the incidence of diaphragmatic dysfunction was comparable between Group H and Group L (65% vs 46%) at 4 h after block placement. Within 24 h after the operation, the maximum VAS pain score of Group H was significantly lower than Group L (P = 0.04), and fewer patients in Group H required rescue analgesics (P < 0.01).

Conclusion

The ICPB with different concentrations of ropivacaine can induce the ipsilateral diaphragmatic dysfunction. The high concentration of ropivacaine results in higher incidence of diaphragmatic dysfunction at 40 min, but comparable incidence at 4 h after block compared with lower concentration of ropivacaine.

Chinese Clinical Trial Registry

ChiCTR2000029348.

Intertruncal versus classical approach to the ultrasound-guided supraclavicular brachial plexus block for upper extremity surgery: study protocol for a randomized non-inferiority trial

Background

Ultrasound-guided intertruncal approach (IA) to the supraclavicular block (SB) is recently proposed as a new approach for local anesthetic (LA) injection in terms of the classical approach (CA) at the level of the first rib. The CA-SB has been proven to result in satisfying sensorimotor block, but associate with a high risk of intraneural injection. The aim of this randomized non-inferiority study is to explore whether IA-SB can obtain similar block dynamics, as the CA-SB, but avoiding an intraneural injection during the whole nerve block procedure.

Methods

The total 122 patients undergoing elective upper extremity surgery will be randomly allocated to receive either an IA-SB or a CA-SB using a double-injection (DI) technique. In the IA-SB group, a portion of LA (15 mL) is injected accurately to the intertruncal plane between the middle and lower trunks under real-time ultrasound guidance; then, the remaining volume (10 mL) is carefully distributed to the other intertruncal plane between the upper and middle trunks. In the CA-SB group, the DI technique will be carried out as described in Tran’s study. The primary outcome is the percentage of patients with a complete sensory blockade at 20 min with a predefined non-inferiority margin of − 5%. The secondary outcomes include the sensory-motor blockade of all 4 terminal nerves, onset times of the individual nerves within 30 min, block-related variables, and adverse events.

Discussion

The results will provide sensory-motor blockade-related parameters and safety of the ultrasound-guided intertruncal approach to the supraclavicular block, thereby promoting clinical practice.

Trial registration

Chinese Clinical Trial Registry ChiCTR2000040199. Registered on 25 November 2020

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06029-x.

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.

Ultrasound-guided supraclavicular vs. retroclavicular block of the brachial plexus: comparison of ipsilateral diaphragmatic function: A randomised clinical trial

BACKGROUND

The ultrasound-guided retroclavicular block (RCB) is a recently described alternative approach to brachial plexus blockade at the level of the cords. Although more distal blockade of the brachial plexus is thought to be associated with a lower incidence of phrenic nerve block, the impact of RCB on ipsilateral diaphragmatic function has not been formally investigated.

OBJECTIVE

To compare the effects of supraclavicular and retroclavicular brachial plexus block on diaphragmatic function.

SETTING

A single tertiary hospital, study period from December 2017 to May 2019.

DESIGN

Double-blinded, randomised study.

PATIENTS

A total of 40 patients undergoing upper extremity surgery below the axilla. Exclusion criteria included significant pulmonary disease, BMI more than 40 and contra-indication to peripheral nerve block.

INTERVENTIONS

Patients were randomised to supraclavicular or retroclavicular brachial plexus block with ropivacaine 0.5%.

OUTCOME MEASURES

Phrenic block was assessed by measuring changes in diaphragmatic excursion using M-mode ultrasound, and maximum inspiratory volume on incentive spirometry from baseline, at 15 and 30 min postblock, and postoperatively. Comparative assessment of block characteristics included timing and distribution of sensory and motor block onset in the upper extremity, and scanning and block performance times.

RESULTS

The incidence of phrenic block in the supraclavicular group was higher by ultrasound imaging (70 vs. 15%) and also by pulmonary function testing (55 vs. 5%), with both diaphragmatic excursion and maximum inspiratory volume decreasing to a greater extent after supraclavicular block (SCB) compared with RCB at 15, 30 min and postoperative time points (repeated measures analysis of variance, P < 0.001). There was no difference in timing and extent of distal arm block, but suprascapular and axillary nerves were more consistently blocked after SCB than after RCB.

CONCLUSION

The current study confirms the hypothesis that a RCB is significantly less likely to affect ipsilateral diaphragmatic function than a SCB.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT02631122.

Cervical erector spinae plane block as a perioperative analgesia method for shoulder arthroscopy: a case series

Shoulder arthroscopy, a common intervention for severe rotator cuff injuries, is associated with severe postoperative pain. Upon performing cervical erector spinae plane (ESP) blocks at the C7 TP (tip or posterior tip) or the posterior tip of the C6 TP posterior tubercle in six patients undergoing shoulder arthroscopy, sensory block was detectable in congruent cervico-thoracic dermatomes. Effective intraoperative and postoperative analgesia were consistently obtained for all six patients. This preliminary study illustrated that the cervical ESP block can be considered a potential simple regional anesthesia method for providing analgesia during shoulder arthroscopy with low risks of diaphragmatic paresis, upper extremity motor paresis, nerve injury and persistent hypotension.

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.

Incidence of hemi-diaphragmatic paresis after ultrasound-guided intermediate cervical plexus block: a prospective observational study

PURPOSE

An intermediate cervical plexus block (CPB) targets the posterior cervical space between the sternocleidomastoid muscle and the prevertebral fascia. The phrenic nerve descends obliquely on the surface of the anterior scalene muscle beneath the prevertebral fascia after originating from the C3-C5 ventral rami. Therefore, the phrenic nerve can be affected by a local anesthetic during an intermediate CPB, depending on the permeability characteristics of the prevertebral fascia. This study investigated whether an intermediate CPB affects the phrenic nerve, inducing hemidiaphragmatic paresis.

METHODS

In this prospective observational study, 20 patients undergoing single-incision transaxillary robot-assisted right thyroidectomy were enrolled. The intermediate CPB (0.25% ropivacaine 0.2 ml/kg) was performed at the C4-5 intervertebral level carefully, without penetrating the prevertebral fascia, before the patient emerged from general anesthesia. Diaphragmatic motions of the block side were measured by M-mode ultrasonography at three time points: before anesthesia (baseline) and at 30 and 60 min after the intermediate CPB. Hemidiaphragmatic paresis was divided into three grades, depending on the percentage of diaphragm movement compared to the baseline: none (> 75%), partial paresis (25-75%), and complete paresis (< 25%).

RESULTS

No patient showed any partial or complete ipsilateral hemidiaphragmatic paresis within 60 min after the intermediate CPB.

CONCLUSION

Intermediate CPB using 0.2 ml/kg of 0.25% ropivacaine at the C4-5 intervertebral level did not cause ipsilateral hemidiaphragmatic paresis. This may imply that the effect of the intermediate CPB on the phrenic nerve is not significant.

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.

A randomised controlled trial of shoulder block vs. interscalene brachial plexus block for ventilatory function after shoulder arthroscopy

The shoulder block may impair ventilatory function and diaphragmatic movement less than the interscalene brachial plexus block. We randomly allocated 30 adults who underwent shoulder arthroscopy under general anaesthesia to ultrasound-guided shoulder block or interscalene block with 20 ml bupivacaine 0.5%. The primary outcome, rate of ultrasound-measured hemidiaphragmatic excursion < 25% of baseline 30 min after blockade, was reduced from 12/15 with brachial plexus block to 2/15 with shoulder block, a difference (95%CI) of 67% (40-93%), p < 0.001. The mean (SD) numeric rating scale pain scores at rest after shoulder block were higher than after interscalene block at two postoperative hours, 1.4 (1.2) vs. 0.3 (0.7), p = 0.02, but lower at 24 postoperative hours, 1.3 (1.3) vs. 3.4 (2.3), p = 0.008. Mean (SD) pain scores on movement in the shoulder and interscalene blocks were similar, with respective values of 1.9 (1.9) vs. 0.7 (1.2), p = 0.13 at two postoperative hours and 3.7 (2.3) vs. 5.3 (2.5), p = 0.41, at 24 postoperative hours.