TY - CHAP M1 - Book, Section TI - Spinal Sonography and Applications of Ultrasound for Central Neuraxial Blocks A1 - Karmakar, Manoj K. A1 - Jinn Chin, Ki A2 - Hadzic, Admir Y1 - 2017 N1 - T2 - Hadzic's Textbook of Regional Anesthesia and Acute Pain Management, 2e AB - Central neuraxial blocks (CNBs), which include spinal, epidural, combined spinal epidural (CSE), and caudal epidural injections, are commonly practiced regional anesthesia techniques and frequently used in the perioperative period for anesthesia and analgesia and for managing chronic pain.1 Traditionally, CNBs are performed using a combination of surface anatomical landmarks, the operator’s perception of tactile sensation (loss of resistance) during needle advancement, and/or visualizing the free flow of cerebrospinal fluid. Although the spinous processes are relatively reliable surface anatomical landmarks in many patients, they are not always easily recognizable in patients with obesity,2 edema, underlying spinal deformity, or previous back surgery. Tuffier’s line, which connects the highest points of the iliac crests, is another surface anatomical landmark that is widely used to estimate the location of the L3–L4 interspace; however, the correlation is inconsistent.3 Even in the absence of spine abnormalities, estimation of a specific intervertebral level may not be accurate in many patients4,5 and may result in needle placement one or two spinal levels higher than intended.4,6,7 The difficulty in identifying the correct spinal level is exaggerated in patients with obesity and in the upper spinal levels.4,6,8 This inaccuracy has been implicated in cases of injury to the conus medullaris after spinal anesthesia.6,8 Moreover, surface landmarks alone do not allow the operator to reliably predict the ease or difficulty of needle placement prior to skin puncture. Unanticipated technical difficulty, multiple attempts at needle placement, and failure of CNB are therefore not uncommon.9,10 Recently, however, ultrasound (US) imaging of the spine has emerged as a useful method of overcoming many of these shortcomings of the surface landmark–guided approach to CNBs. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessanesthesiology.mhmedical.com/content.aspx?aid=1141735352 ER -