Regional anesthesia for elbow, wrist and hand surgery
Distal upper extremity surgery is particularly suited to regional anesthesia. Brachial plexus bock can readily produce surgical anesthesia in < 30 mins, 1 and the peripheral nature of the surgery makes it amenable to being conducted awake or under light sedation. Compared to general anaesthesia, two independent randomized controlled trials have shown early outcome improvements when this surgey is conducted under bracial plexus block awake or with concomitant light sedation. These early outcome benefits include reduced nausea/vomiting, improved patient satisfaction and accelerated recovery room and hospital discharge. Brachial plexus block also provides potent postoperative analgesia.
Three approaches to brachial plexus block have gained popularity for distal upper extremity surgery: supraclavicular, infraclavicular and axillary block. 2 When a narrow footprint curved probe is available (e.g. Sonosite C11), which facilitates probe and needle access to the deltopectoral groove, we prefer ultrasound guided infraclavicular block for several reasons.
Compared to ultrasound guided supraclavicular block, 3 of 4 independently conducted adult, observer blinded, randomised trials 2-5 have demonstrated that ultrasound-guided infraclavicular block is associated with a higher success rate for both experienced 3, 5 and trainee operators. 4, 5 It is also associated with a lower risk of procedure induced paresthesia (p≤0.10), 3, 4 a lower risk of phrenic nerve block (dyspnea) 4 and reduced block of the ascending sympathetic chain (Horner’s syndrome). 2, 4 Supraclavicular block typically involves a lateral-to-medial needle orientation towards the inferior trunks of the plexus, which lie adjacent to the apex of the lung. If needle tip visualisation proves difficult, there is a real risk of pneumothorax with the supraclavicular approach.
In contrast, single injection ultrasound guided infraclavicular block is procedurally a much simpler alternative. In experienced hands, it can be performed in 2-3 mins, 6 and relies on just advancing the needle through the fascia cephaloposterior to the axillary artery and then depositing 30-35 mL of local anesthetic. Brachial plexus imaging is not an absolute requirement for success, therefore the technique is rarely limited by suboptimal patient ultrasonography e.g. obesity. Provided the needle remains lateral, pleural puncture is almost impossible and thus precise needle tip visualization is not essential in avoiding pneumothorax. It is also particularly suited to the supine position with the anesthesiologist in their usual position at the head of the bed/operating table. Relative contraindications are rare for elective surgery; the most common in our experience being a pacemaker in the path of the needle passage. An important consideration relevant to the choice of brachial plexus block approach is that compared to blocks above the clavicle, blocks below the clavicle result in lower peak local anesthetic plasma levels. 7 Finally, the infraclavicular needle puncture site is particularly suited to catheter fixation.
We only use the axillary approach if alternative approaches are contraindicated. This is because of the requirement for arm abduction/external rotation; 2 evidence suggesting a high success rate requires separate multiple injections adjacent each of the four nerves, 2 and the difficulty securing a catheter at this location.
SS distal median/ulnar and radial blocks can be used as the primary regional anesthesia for wrist and hand surgery, 8, 9 however, because of the usual requirement for tourniquet analgesia, they are more commonly used to supplement a more proximal brachial plexus block e.g. infraclavicular block. Supplementation in this situation means either to complete a “patchy” brachial plexus block, or to accelerate the onset of upper extremity anesthesia. 1
1. Fredrickson MJ, Ting FS, Chinchanwala S, et al. Concomitant infraclavicular plus distal median, radial, and ulnar nerve blockade accelerates upper extremity anaesthesia and improves block consistency compared with infraclavicular block alone. Br J Anaesth 2011;107:236-42.
2. Tran de QH, Russo G, Munoz L, et al. A prospective, randomized comparison between ultrasound-guided supraclavicular, infraclavicular, and axillary brachial plexus blocks. Reg Anesth Pain Med 2009;34:366-71.
3. Fredrickson MJ, Patel A, Young S, et al. Speed of onset of 'corner pocket supraclavicular' and infraclavicular ultrasound guided brachial plexus block: a randomised observer-blinded comparison. Anaesthesia 2009;64:738-44.
4. Koscielniak-Nielsen ZJ, Frederiksen BS, Rasmussen H, et al. A comparison of ultrasound-guided supraclavicular and infraclavicular blocks for upper extremity surgery. Acta Anaesthesiol Scand 2009;53:620-6.
5. Mariano ER, Sandhu NS, Loland VJ, et al. A randomized comparison of infraclavicular and supraclavicular continuous peripheral nerve blocks for postoperative analgesia. Reg Anesth Pain Med 2011;36:26-31.
6. Fredrickson MJ, Wolstencroft P, Kejriwal R, et al. Single versus triple injection ultrasound-guided infraclavicular block: confirmation of the effectiveness of the single injection technique. Anesth Analg 2010;111:1325-7.
7. Rettig HC, Lerou JG, Gielen MJ, et al. The pharmacokinetics of ropivacaine after four different techniques of brachial plexus blockade. Anaesthesia 2007;62:1008-14.
8. Delaunay L, Chelly JE. Blocks at the wrist provide effective anesthesia for carpal tunnel release. Can J Anaesth 2001;48:656-60.
9. Macaire P, Choquet O, Jochum D, et al. Nerve blocks at the wrist for carpal tunnel release revisited: the use of sensory-nerve and motor-nerve stimulation techniques. Reg Anesth Pain Med 2005;30:536-40.