RT Book, Section A1 Blanco, Rafael A1 Barrington, Michael J. A2 Hadzic, Admir SR Print(0) ID 1141734765 T1 Pectoralis and Serratus Plane Blocks T2 Hadzic's Textbook of Regional Anesthesia and Acute Pain Management, 2e YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9780071717595 LK accessanesthesiology.mhmedical.com/content.aspx?aid=1141734765 RD 2024/04/25 AB Pectoralis nerve (Pecs) and serratus plane blocks are newer ultrasound (US)-guided regional anesthesia techniques of the thorax.1 The increasing use of ultrasonography to identify tissue layers and, particularly, fascial layers has led to the development of several newer interfascial injection techniques for analgesia of the chest and abdominal wall. For instance, the Pecs I block was devised to anesthetize the medial and lateral pectoral nerves, which innervate the pectoralis muscles.1 This is accomplished by an injection of local anesthetic in the fascial plane between the pectoralis major and minor muscles. The Pecs II block (which also includes the Pecs I block) is an extension that involves a second injection lateral to the Pecs I injection point in the plane between the pectoralis minor and serratus anterior muscles with the intention of providing blockade of the upper intercostal nerves.2 A further modification is the serratus plane block, in which local anesthetic is injected between the serratus anterior and latissimus dorsi muscles.3 These interfascial injections were developed as alternatives to thoracic epidural, paravertebral, intercostal, and intrapleural blocks, primarily for analgesia after surgery on the hemithorax. Initially, Pecs blocks were intended for analgesia after breast surgery; however, case reports have also described the use of Pecs and serratus plane blocks for analgesia following thoracotomy4 and rib fracture.5