Letters to the Editor
To the Editor
Kimachi et al1 demonstrated the efficacy of erector spinae plane (ESP) block for mastectomy and axillary dissection. We would like to highlight that the breast and axilla are innervated not only by intercostal nerves, but also by the brachial plexus. ESP block anesthetizes intercostal nerves both in paravertebral space and in ESP, but it is not clear that an ESP block is able to consistently provide anesthesia for branches of the brachial plexus. Forero et al2 showed that an ESP block executed at T2–3 level does provide anesthesia to rami of the brachial plexus. However, the spread of local anesthetic during a ESP block is not predictable (from 2.5 to 6.6 mL to cover 1 dermatome).3 For this reason, it is not possible to state that brachial plexus rami will be anesthetized every time an ESP block is executed.
We suggest that a selective block of brachial plexus rami involved in breast and axilla innervation (medial and lateral pectoral nerves, long thoracic nerve, and thoracodorsal nerve) could guarantee complete anesthesia of the area. Medial and lateral pectoral block is easily achieved by injecting 7–10 mL of local anesthetic between pectoralis major muscle and pectoralis minor muscle using the thoracoacromial artery as landmark. The long thoracic nerve is identifiable inside the middle scalene muscle (Figure A) and blocked with 2–3 mL of local anesthetic. The thoracodorsal nerve has close relationship with lateral thoracic vein4 and usually can be identified nearby (Figure B) and then blocked with 2–3 mL of local anesthetic. Further studies are needed to understand the relationship between an ESP block and rami of the brachial plexus and determine whether our recommendation is an unnecessary precaution.
Alessandro De Cassai, MD
Irina Ban, MD
Department of Medicine (DIMED)
Section of Anaesthesiology and Intensive Care
University of Padua
1. Kimachi PP, Martins EG, Peng P, Forero MThe erector spinae plane block provides complete surgical anesthesia in breast surgery: a case report. A A Pract. 2018;11:186188.
2. Forero M, Rajarathinam M, Adhikary SD, Chin KJErector spinae plane block for the management of chronic shoulder pain: a case report. Can J Anesth. 2018;65:288293.
3. De Cassai A, Tonetti TLocal anesthetic spread during erector spinae plane block. J Clin Anesth. 2018;48:6061.
4. Zin T, Maw M, Oo S, Pai D, Paijan R, Kyi MHow I do it: simple and effortless approach to identify thoracodorsal nerve on axillary clearance procedure. Ecancermedicalscience. 2012;6:255.