Subcoracoid tunnel block as an alternative infraclavicular brachial plexus approach -a case series.

BACKGRUOND: Magnetic resonance neurography shows the brachial plexus cords in the subcoracoid tunnel beneath the pectoralis minor. With an ultrasound scan along the brachial line, the brachial plexus cords in the subcoracoid tunnel can be targeted using an in-plane needle approach. We describe this new approach to the infraclavicular block called the "subcoracoid tunnel block." CASE: Twenty patients were administered with the ultrasound-guided subcoracoid tunnel block for the below-elbow surgery. The contact of the needle tip with cords was visible in all 20 patients. With neurostimulation, the posterior cord was identified in 11 (55%) and medial cord in 9 (45%) patients on the first needle pass. The subcoracoid tunnel block was successful in 16 patients (80%). CONCLUSIONS: Our case series shows that the subcoracoid tunnel block is an excellent alternative technique for the infraclavicular block. Its advantages include better needle-cord visibility and easy identification of the brachial plexus cords.

Effects of catheter orifice configuration (triple-hole versus end-hole) in continuous infraclavicular brachial plexus block on analgesia after upper limb surgery.

BACKGROUND: The configuration of a nerve block catheter may affect the local anesthetic spread in epidural analgesia and continuous peripheral nerve blocks. This prospective and randomized study aims to compare the multi-orifice nerve block catheter with an end-hole catheter in ultrasound-guided continuous infraclavicular brachial plexus block (BPB) in terms of providing postoperative analgesia for the orthopedic upper limb surgery below the shoulder. The primary outcome measure was mean pain scores. Secondary outcome measures were the consumption of rescue analgesic and the amount of local anesthetics delivered by a Patient-Controlled Analgesia (PCA) device. METHODS: A total of 58 adult patients who underwent orthopedic upper limb surgery below the shoulder were randomly assigned into two groups: group end-hole catheter (EHC) (n=31) and group multi-orifice catheter (MOC) (n=27). All patients received a single-shot infraclavicular BPB using 100 mg lidocaine 2% and 75 mg bupivacaine 0.5% administrated through a Tuohy needle. Then, a multi-orifice (triple-hole) nerve catheter was placed in the group MOC and an end-hole (one-hole) catheter in the group EHC at the same location. Bupivacaine 0.125% was infused through the catheters via PCA (infusion rate: 2 mlh-1, automated regular bolus: 5 mlh-1, patient-controlled bolus: 3 ml, lock-out time: 1 hour, 4 hours limit: 40 ml). Pain intensity was evaluated using a visual analogue scale (VAS). RESULTS: Mean VAS scores were higher in group EHC than group MOC in the first postoperative day (p=0.001). Mean rescue analgesic consumption, the number of bolus demand on PCA, PCA bolus demand dose, and total PCA dose were higher in group EHC than group MOC during the first postoperative day (p<0.05). CONCLUSION: It is concluded that the use of MHC is more effective than EHC for continuous infraclavicular brachial plexus blocks in providing postoperative pain relief during the first 24 hours.

Tissue Oxygen Saturation Change on Upper Extremities After Ultrasound-Guided Infraclavicular Brachial Plexus Blockade; Prospective Observational Study.

Background and Objective: The aim of this study was to investigate whether tissue oxygen saturation (StO2) is a reliable and objective method for assessing the adequacy of infraclavicular block and to describe the time course of StO2 changes. Materials and Methods: In this prospective observational study, StO2 was measured in 40 patients planned for elective hand surgery under infraclavicular block. Noninvasive StO2 monitoring was used prior to ultrasound-guided infraclavicular brachial plexus block and during the first 30 min of the blockade. Sensory and motor blocks were evaluated every 5 min followed by pinprick testing and Bromage scale. Results: Preanesthetic median StO2 values of the blocked side and nonblocked side were similar (p = 0.532), whereas the postanesthetic values of the blocked side were higher. At the fifth minute and the following minute, measurements compared to the nonblocked side (p < 0.001). The median StO2 values increased significantly, which increased by 4.5% at 5 min, by another 5.5% at 30 min, and by an average of 1% from 5 to 30 min compared to the baseline values in the blocked side. The responses of the patients to the questions probed in the pinprick test and Bromage scale were fully compatible with the data obtained by the near-infrared spectroscopy (NIRS) method. Conclusions: StO2 monitoring may provide a useful instrument for rapid evaluation of the success of regional anesthesia in the upper extremity.

A Cadaver Study Investigating Structures Encountered by the Needle During a Retroclavicular Approach to Infraclavicular Brachial Plexus Block.

BACKGROUND AND OBJECTIVES: Retroclavicular block is designed to overcome the negative aspects of the commonly utilized ultrasound-guided parasagittal approach to the infraclavicular block. However, this approach necessitates the needle traversing an area posterior to the clavicle inaccessible to ultrasound wave conduction. This study sought to document the structures vulnerable to needle injury during a retroclavicular block. METHODS: A Tuohy needle was inserted using a retroclavicular approach to the infraclavicular block in 3 lightly embalmed cadavers followed by a catheter insertion 4 cm beyond the needle tip. The process was repeated on the contralateral side. With the needle and catheter in position, the cadavers were dissected and photographed. RESULTS: In 4 of the 6 dissections, the needle was directly touching the suprascapular nerve deep to the clavicle. In the remaining 2 dissections, the suprascapular nerve was within 2 cm of the needle. In 1 dissection, the suprascapular vein was indented, behind the clavicle. The trapezius was the only muscle layer traversed by the needle in all dissections. In 3 of the 6 dissections, the catheter penetrated the posterior cord. In the remaining 3, the catheter threaded along the neurovascular bundle. CONCLUSIONS: The suprascapular nerve is consistently in the path of the block needle posterior to the clavicle. This raises the possibility of risk of injury to the suprascapular nerve when using this approach to the brachial plexus. Vascular injury is also possible deep to the clavicle, and because of the noncompressible location, caution is advised in patients with disordered coagulation.

Infraclavicular versus axillary nerve catheters: A retrospective comparison of early catheter failure rate.

STUDY OBJECTIVES: Continuous brachial plexus catheters are often used to decrease pain following elbow surgery. This investigation aimed to assess the rate of early failure of infraclavicular (IC) and axillary (AX) nerve catheters following elbow surgery. DESIGN: Retrospective study. SETTING: Postoperative recovery unit and inpatient hospital floor. PATIENTS: 328 patients who received IC or AX nerve catheters and underwent elbow surgery were identified by retrospective query of our institution's database. MEASUREMENTS: Data collected included unplanned catheter dislodgement, catheter replacement rate, postoperative pain scores, and opioid administration on postoperative day 1. Catheter failure was defined as unplanned dislodging within 24 h of placement or requirement for catheter replacement and evaluated using a covariate adjusted model. MAIN RESULTS: 119 IC catheters and 209 AX catheters were evaluated. There were 8 (6.7%) failed IC catheters versus 13 (6.2%) failed AX catheters. After adjusting for age, BMI, and gender there was no difference in catheter failure rate between IC and AX nerve catheters (p = 0.449). CONCLUSIONS: These results suggest that IC and AX nerve catheters do not differ in the rate of early catheter failure, despite differences in anatomic location and catheter placement techniques. Both techniques provided effective postoperative analgesia with median pain scores < 3/10 for patients following elbow surgery. Reasons other than rate of early catheter failure should dictate which approach is performed.

Regional Anaesthesia in Clavicle Surgery.

In routine practice, regional anaesthesia is less commonly used for clavicular fracture compared to general anaesthesia. We report two cases of clavicle fracture for which operative treatment was done under combined superficial cervical plexus and interscalene brachial plexus block. In both the cases combination of ropivacaine and dexmeditomidine was used for block. Both the patients exhibited comfort and there was no additional analgesic demand in both the cases. Thus combination of interscalene and superficial cervical plexus block can prove to be useful in patients with clavicle fracture where administration of general anaesthesia and its adverse effects could be avoided.

Double-injection technique assisted by a nerve stimulator for ultrasound-guided supraclavicular brachial plexus block results in better distal sensory-motor block: A randomised controlled trial.

BACKGROUND: To evaluate the efficacy of a nerve stimulator when used with ultrasound-guided double injection in supraclavicular brachial plexus block. OBJECTIVES: We hypothesised that targeting the inferior trunk of the plexus guided by a nerve stimulator would obtain a higher success rate of ulnar nerve blockade than the traditional double-injection technique. DESIGN: A blinded randomised controlled study. SETTING: Conducted at the University Hospital from October 2015 to January 2016. PATIENTS: Ninety patients undergoing upper extremity surgery were randomised into two equal groups. INTERVENTIONS: Patients were randomly allocated to a modified double-injection group (MDI group) or a traditional double-injection group (DI group). All patients received 23 ml of a 1 : 1 mixture of 2% lidocaine and 1% ropivacaine during ultrasound-guided supraclavicular brachial plexus block. In the MDI group (n = 45), half the volume was deposited within the brachial plexus sheath guided by ultrasound, next to the inferior trunk and verified by nerve stimulation; the remaining volume was deposited in the main neural cluster. In the double-injection group (n = 45), the first half volume was deposited on ultrasound guidance alone. Sensory-motor blockade of the musculocutaneous, median, radial, ulnar nerves and surgical anaesthesia, performance time, number of needle passes and complications were recorded. MAIN OUTCOME MEASURES: The success rate of complete sensory block of the ulnar nerve within 15 min after local anaesthetic injection. RESULTS: Compared with the DI group the MDI group had higher success rates of complete sensory block of the ulnar nerve (93 vs 67%, P = 0.002) and complete anaesthesia (80 vs 56%, P = 0.014) at 15 min, whereas the average performance time was significantly longer (5.08 ±â€Š1.41 vs 4.10 ±â€Š0.64 min, P < 0.001) and the number of needle passes was significantly higher (4.40 ±â€Š1.14 vs 2.87 ±â€Š0.79, P < 0.001). CONCLUSION: The MDI technique has a higher success rate for complete sensory block of the ulnar nerve within 15 min of local anaesthetic injection. The time needed to perform the block is about 1 min longer than the traditional technique. TRIAL REGISTRATION: http://www.chictr.org.cn with the registration number of ChiCTR-IOR-15007588.

No correlation between minimal electrical charge at the tip of the stimulating catheter and the efficacy of the peripheral nerve block catheter for brachial plexus block: a prospective blinded cohort study.

BACKGROUND: Stimulating catheters offer the possibility of delivering an electrical charge via the tip of the catheter. This may be advantageous as it allows verifying if the catheter tip is in close proximity to the target nerve, thereby increasing catheter performance. This prospective blinded cohort study was designed to investigate whether there is a correlation between the minimal electrical charge at the tip of the stimulating catheter, and the efficacy of the peripheral nerve block (PNB) catheter as determined by 24 h postoperative morphine consumption. METHODS: Forty adult patients with ASA physical health classification I-III scheduled for upper extremity surgery under combined continuous interscalene block and general anesthesia were studied. Six patients were excluded from analysis.After inserting a stimulating catheter as if it were a non-stimulating catheter for 2-5 cm through the needle, the minimal electrical charge necessary to obtain an appropriate motor response was determined. A loading dose of 20 mL ropivacaine 0.75% ropivacaine was then administered, and postoperative analgesia was provided by a continuous infusion of ropivacaine 0.2% 8 mL.h-1 via the brachial plexus catheter, and an intravenous morphine patient-controlled analgesia (PCA) device.Main outcome measures include the minimal electrical charge (MEC) at the tip of the stimulating catheter necessary to elicit an appropriate motor response, and the efficacy of the PNB catheter as determined by 24 h postoperative PCA morphine consumption. RESULTS: Mean (SD) [range] MEC at the tip of the stimulating catheter was 589 (1414) [30 - 5000] nC. Mean (SD) [range] 24 h morphine consumption was 8.9 (9.9) [0-29] mg. The correlation between the MEC and 24 h postoperative morphine consumption was Spearman's Rho rs = -0.26, 95% CI -0.56 to 0.09. CONCLUSION: We conclude that there is no proportional relation between MEC at the tip of the blindly inserted stimulating catheter and 24 h postoperative morphine consumption. TRIAL REGISTRATION: Trialregister.nl identifier: NTR2328.