RT Book, Section A1 Gautier, Philippe A2 Hadzic, Admir SR Print(0) ID 1141730324 T1 Disposition of Injectate with Common Regional Anesthesia Techniques 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=1141730324 RD 2024/03/28 AB The outcome of regional anesthesia technique is ultimately dependent on the distribution of the local anesthetic in the relevant tissue space that contains the nerve(s) of interest. Prior to the introduction of ultrasound in regional anesthesia, our understanding of the disposition of the local anesthetic had been limited due to the lack of technology that could allow such monitoring. This addendum features studies of computed tomographic (CT) images that we painstakingly acquired by the author over a period of nearly 2 decades in attempt to elucidate the disposition of local anesthetic injections with nerve block injections and their relationship to the outcome of regional anesthesia. The maldistribution of local anesthetic associated with block failures and/or complications due to the spillage of local anesthetic to the undesired places, such as, for example, the phrenic nerv and neuraxial space are also demonstrated. A uniquely educational aspect of these images is the relationship of the volume of the injectate and its physical spread in the tissue spaces.