Regional Anesthesia and Pain Control Efficacy of Pectoral Nerve Block Versus Thoracic Paravertebral Block for Postoperative Analgesia After Radical Mastectomy: A Randomized Controlled Trial S. Kulhari, N. Bharti, I. Bala, S. Arora, and G. Singh (Abstracted from Br J Anaesth, 2016;117(3):382–386) Department of Anaesthesia and Intensive Care Postgraduate Institute of Medical Education and Research, Chandigarh, India. T horacic paravertebral block (TPVB) is the preferred mode of postoperative analgesia following breast surgeries, but various complications, such as risk of pneumothorax, spinal cord trauma, sympathetic block, and hypotension, have been reported with TPVB. Pectoral nerve (PecS) block is a new approach that aims to block the pectoral, the intercostobrachial, the intercostals III and VI, and the long thoracic nerves, thus providing complete sur- gical anesthesia and postoperative analgesia in breast surgery. This technique is effective for surgical procedures such as place- ment of breast expanders and subpectoral prosthesis, shoulder sur- gery with deltopectoral groove involvement, and insertion of a pacemaker or intercostal drain. The PecS II has minor complica- tions (intravascular injection in the acromiothoracic artery and ce- phalic vein, and pneumothorax) and is considered a safe option for postoperative analgesia. A study was conducted to compare the efficacy and safety of ultrasound-guided PecS II block with TPVB for postoperative analgesia after modified radical mastectomy. Approximately 40 American Society of Anesthesiologists grade I–II female patients in the age group of 18 to 65 years, undergoing modified radical mas- tectomy under general anesthesia between April and December 2014, were included in this study and were allocated into 2 groups. One group received TPVB, and the other received PecS II block. The test results showed that the duration of postoperative analgesia was prolonged in patients receiving the PecS II block compared with TPVB (mean, 197.5 [SD, 31.35] minutes vs 294.5 [SD, 52.76] minutes; P < 0.0001). The total 24-hour morphine con- sumption was reduced in patients receiving PecS (mean, 3.90 [SD, 0.79] vs 5.30 [SD, 0.98] mg in the PecS II and TPVB groups, respectively; P < 0.0001). The test results concluded that PecS II block is effective in providing postoperative analgesia with re- duced postoperative opioid consumption compared with TVPB in patients who underwent radical mastectomy without causing adverse effects. Further studies are recommended for evaluating the efficacy of the PecS II block for preventing chronic postsurgi- cal pain after radical mastectomy. COMMENT Pectoral fascial plane blocks are relatively newly described blocks used for analgesia and surgical anesthesia in a variety of surgical procedures involving the structures of the chest and shoulder. First described by Blanco et al 1 in 2011, the Pecs (or Pecs I) block is a fascial plane block with local anesthetic injected between the pectoralis major and minor muscles to block medial pectoral and lateral PecS. It was initially presented as an alterna- tive to epidural or paravertebral blockade for analgesia after sur- geries of the breast. Blanco et al 2 later described a modified pectoral (or Pecs II) block, which aims to provide complete anal- gesia or anesthesia for breast surgery by blocking nerves supply- ing the pectoral muscles, serratus muscle, axilla, and breast tissue. Multiple studies exist establishing an analgesic benefit of paravertebral blockade for breast surgery, but currently few exist comparing paravertebral block to pectoral plane blocks for analge- sia after breast surgery. In this randomized controlled trial by Kulhari et al, the post- operative analgesic effects of TPVB versus Pecs II block were compared after modified radical mastectomy surgery in a total of 40 patients. The primary outcomes were duration of analgesia, measured as time to first rescue analgesic after block placement, and total morphine consumption in the first 24 hours after block administration. The study authors found a statistically significant advantage for Pecs II block over TPVB in both primary out- comes, although only block duration may prove to be clinically significant. Analgesia from Pecs II blockade lasted a mean of 97 minutes (49%) longer than paravertebral blockade; how- ever, absolute total morphine consumption between groups dif- fered by only 1.4 mg over 24 hours. Secondary outcomes studied were postoperative pain and adverse effects from block. Postoperative pain was measured by visual analog scale and fa- vored Pecs II, but only in the first 2 hours and with absolute re- duction ranging from means of 0 to 2 on 10-point visual analog scale, which may be questionably relevant clinically. The findings of this study support the use of Pecs II block as an alternative to TPVBs for breast surgery. At minimum, the blocks seem to offer comparable pain control after modified radi- cal mastectomy, and this study shows a clear duration advantage for Pecs II over TPVB. As the study authors point out, the poten- tial risk profile of Pecs II block over TPVB is more favorable, par- ticularly eliminating risk of potential epidural/intrathecal spread and sympathetic blockade and lowering the risk of pneumothorax due to block site and use of ultrasound. The findings of this study support the use of the Pecs II block for analgesia in breast surgery as an alternative to TPVB. Comment by Sarah Kittner, MD Disclosure: The authors declare no conflict of interest. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/SA.0000000000000289 REFERENCES 1. Blanco R. The ‘Pecs block’: a novel technique for providing analgesia after breast surgery. Anaesthesia. 2011;66(9):847–848. 2. Blanco R, Fajardo M, Parras Maldonado T. Ultrasound description of Pecs II (modified Pecs I): a novel approach to breast surgery. Rev Esp Anestesiol Reanim. 2012;59(9):470–475. 22 www.surveyanesthesiology.com Survey of Anesthesiology • Volume 61, Number 1, February 2017 Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.