A randomised placebo-controlled trial examining the effect on hand supination after the addition of a suprascapular nerve block to infraclavicular brachial plexus blockade

This is the peer reviewed version of the following article: Flohr-Madsen, S., Ytrebø, L.M., Valen, K., Wilsgaard, T. & Klaastad, Ø. (2016). A randomised placebo-controlled trial examining the effect on hand supination after the addition of a suprascapular nerve block to infraclavicular brachial plexus blockade. Anaesthesia, 71, 938–947, which has been published in final form at https://doi.org/10.1111/anae.13504. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Some surgeons believe that infraclavicular brachial plexus blocks tends to result in supination of the hand/forearm, which may make surgical access to the dorsum of the hand more difficult. We hypothesised that this supination may be reduced by the addition of a suprascapular nerve block. In a double‐blind, randomised, placebo‐controlled study, our primary outcome measure was the amount of supination (as assessed by wrist angulation) 30 min after infraclavicular brachial plexus block, with (suprascapular group) or without (control group) a supplementary suprascapular block. All blocks were ultrasound‐guided. The secondary outcome measure was an assessment by the surgeon of the intra‐operative position of the hand. Considering only patients with successful nerve blocks, mean (SD) wrist angulation was lower (33 (27) vs. 61 (44) degrees; p = 0.018) and assessment of the hand position was better (11/11 vs. 6/11 rated as ‘good’; p = 0.04) in the suprascapular group. The addition of a suprascapular nerve block to an infraclavicular brachial plexus block can provide a better hand/forearm position for dorsal hand surgery

Studies of peripheral nerve blocks for hand and shoulder surgery

Performing regional anesthesia with a minimum effective volume (MEV) of local anesthetic may reduce the risk of systemic local anesthesia toxicity. The lateral sagittal infraclavicular block (LSIB) is a well-established anesthesia method for surgery distal to the shoulder. For LSIB using ropivacaine 7.5 mg/ml the MEV was previously not known and we estimated MEV95 to be 31 ml (95% CI, 18 – 45 ml). LSIB tends to result in supination of the hand/forearm, which may inhibit surgical access to the dorsum of the hand. Supination of the hand and forearm usually occurs by lateral rotation of the radius. When the upper limb is extended, supination may be obtained also by lateral rotation of the humerus. The main lateral rotator of the humerus is the infraspinatus muscle, innervated by the suprascapular nerve. In study II we hypothesised that this supination may be reduced by the addition of a suprascapular nerve block (SSNB) to the LSIB. The study showed that this combination provided a better hand/forearm position for dorsal hand surgery than LSIB alone. Interscalene brachial plexus block (ISB) has been the gold standard for pain management in patients undergoing shoulder surgery. It has a very high success rate, but with a high incidence of phrenic nerve block. Diaphragm-sparing alternatives have therefore been investigated. In study II we applied SSNB primarily because we wanted to prevent lateral rotation of the humerus, but chest radiographs documented that the combination of LSIB and SSNB did not cause paresis of the diaphragm. In study III we hypothesised that the combination of superficial cervical plexus block, SSNB and LSIB would provide a good alternative to the ISB with a lower risk of phrenic paresis. The triple block was shown to be feasible for arthroscopic shoulder surgery

Minimum effective volume of ropivacaine 7.5mg/ml for an ultrasound-guided infraclavicular brachial plexus block

Background - Ultrasound guidance has been shown to reduce the minimum effective volume (MEV) of local anaesthetics for several peripheral nerve blocks. Although the lateral sagittal infraclavicular block (LSIB) is a well‐established anaesthesia method, MEV for this technique has not been established. Our aim with this study was to determine the MEV using ropivacaine 7.5 mg/ml for the LSIB method. Methods - Twenty‐five adult American Society of Anesthesiologists physical status I‐II patients scheduled for hand surgery received an ultrasound‐guided LSIB with ropivacaine 7.5 mg/ml. A successful block was defined as anaesthesia or analgesia for all five sensory nerves distal to the elbow, 30 min after local anaesthetic injection. The MEV for a successful block in 50% of the patients was determined by using the staircase up‐and‐down method introduced by Dixon and Massey. Logistic regression and probit transformation were applied to estimate the MEV for a successful block in 95% of the patients. Results - The patients received ropivacaine 7.5 mg/ml volumes in the range of 12.5–30 ml. The MEVs in 50% and 95% of the patients were 19 ml [95% confidence interval (CI), 14–27] and 31 ml (95% CI, 18–45), respectively. Conclusions - For surgery distal to the elbow, the MEV in 95% of patients for an ultrasound‐guided LSIB with ropivacaine 7.5 mg/ml was estimated to be 31 ml (95% CI, 18–45 ml). Further studies should determine the factors that influence the volume of local anaesthetic required for a successful infraclavicular block

A novel combination of peripheral nerve blocks for arthroscopic shoulder surgery

Background - Interscalene brachial plexus block is currently the gold standard for intra‐ and post‐operative pain management for patients undergoing arthroscopic shoulder surgery. However, it is associated with block related complications, of which effect on the phrenic nerve have been of most interest. Side effects caused by general anesthesia, when this is required, are also a concern. We hypothesized that the combination of superficial cervical plexus block, suprascapular nerve block, and infraclavicular brachial plexus block would provide a good alternative to interscalene block and general anesthesia. Methods - Twenty adult patients scheduled for arthroscopic shoulder surgery received a combination of superficial cervical plexus block (5 ml ropivacaine 0.5%), suprascapular nerve block (4 ml ropivacaine 0.5%), and lateral sagittal infraclavicular block (31 ml ropivacaine 0.75%). The primary aim was to find the proportion of patients who could be operated under light propofol sedation, without the need for opioids or artificial airway. Secondary aims were patients' satisfaction and surgeons' judgment of the operating conditions. Results - Nineteen of twenty patients (95% CI: 85–100) underwent arthroscopic shoulder surgery with light propofol sedation, but without opioids or artificial airway. The excluded patient was not comfortable in the beach chair position and therefore received general anesthesia. All patients were satisfied with the treatment on follow‐up interviews. The surgeons rated the operating conditions as good for all patients. Conclusion - The novel combination of a superficial cervical plexus block, a suprascapular nerve block, and an infraclavicular nerve block provides an alternative anesthetic modality for arthroscopic shoulder surgery