There was no spread of dye anteriorly to the paravertebral space to involve origins of the ventral and dorsal branches of the thoracic spinal nerves. Dorsal ramus involvement was posterior to the costotransverse foramen.

The Second American Society of Regional Anesthesia and Pain Medicine Practice Advisory on Neurologic Complications Associated With Regional Anesthesia and Pain Medicine updates information that was originally presented at the Society's first open forum on this subject (2005) and published in 2008. Portions of the second advisory were presented in an open forum (2012) and are herein updated, with attention to those topics subject to evolving knowledge since the first and second advisory conferences. The second advisory briefly summarizes recommendations that have not changed substantially. New to this iteration of the advisory is information related to the risk of nerve injury inherent to common orthopedic surgical procedures. Recommendations are expanded regarding the preventive role of various monitoring technologies such as ultrasound guidance and injection pressure monitoring. New clinical recommendations focus on emerging concerns including spinal stenosis and vertebral canal pathologies, blood pressure management during neuraxial anesthesia, administering blocks in anesthetized or deeply sedated patients, patients with preexisting neurologic disease, and inflammatory neuropathies. An updated diagnostic and treatment algorithm is presented.

This anatomical study shows that an ultrasound-guided TAP injection cephalad to the iliac crest is likely to involve the T10-L1 nerve roots, and implies that the technique may be limited to use in lower abdominal surgery.

Previous descriptions of the thoracolumbar spinal nerves innervating the anterior abdominal wall have been inconsistent. With modern surgical and anesthetic techniques that involve or may damage these nerves, an improved understanding of the precise course and variability of this anatomy has become increasingly important. The course of the nerves of the anterior abdominal is described based on a thorough cadaveric study and review of the literature. Twenty human cadaveric hemi-abdominal walls were dissected to map the course of the nerves of the anterior abdominal wall. Dissection included a comprehensive tracing of nerves and their branches from their origins in five specimens. The branching pattern and course of all nerves identified were described. All thoracolumbar nerves that innervate the anterior abdominal wall were found to travel as multiple mixed segmental nerves, which branch and communicate widely within the transversus abdominis plane (TAP). This communication may occur at multiple locations, including large branch communications anterolaterally (intercostal plexus), and in plexuses that run with the deep circumflex iliac artery (DCIA) (TAP plexus) and the deep inferior epigastric artery (DIEA) (rectus sheath plexus). Rectus abdominis muscle is innervated by segments T6-L1, with a constant branch from L1. The umbilicus is always innervated by a branch of T10. As such, identification or damage to individual nerves in the TAP or within rectus sheath is unlikely to involve single segmental nerves. An understanding of this anatomy may contribute to explaining clinical outcomes and preventing complications, following TAP blocks for anesthesia and DIEA perforator flaps for breast reconstruction.

This study provides the strongest evidence, to date, that ultrasound guidance may improve safety because it is associated with a reduced risk of LAST following PNB.

A catheter can be placed along the oblique subcostal line in the transversus abdominis plane for continuous infusion of local anesthetic. Multimodal analgesia and intravenous opioid are used in addition because visceral pain is not blocked. Continuous oblique subcostal transversus abdominis plane block is a new technique and requires both a detailed knowledge of sonographic anatomy and technical skill for it to be successful.

The American Society of Regional Anesthesia and Pain Medicine's Third Practice Advisory on local anesthetic systemic toxicity is an interim update from its 2010 advisory. The advisory focuses on new information regarding the mechanisms of lipid resuscitation, updated frequency estimates, the preventative role of ultrasound guidance, changes to case presentation patterns, and limited information related to local infiltration anesthesia and liposomal bupivacaine. In addition to emerging information, the advisory updates recommendations pertaining to prevention, recognition, and treatment of local anesthetic systemic toxicity. WHAT'S NEW IN THIS UPDATE?: This interim update summarizes recent scientific findings that have enhanced our understanding of the mechanisms that lead to lipid emulsion reversal of LAST, including rapid partitioning, direct inotropy, and post-conditioning. Since the previous practice advisory, epidemiological data have emerged that suggest a lower frequency of LAST as reported by single institutions and some registries, nevertheless a considerable number of events still occur within the general community. Contemporary case reports suggest a trend toward delayed presentation, which may mirror the increased use of ultrasound guidance (fewer intravascular injections), local infiltration techniques (slower systemic uptake), and continuous local anesthetic infusions. Small patient size and sarcopenia are additional factors that increase potential risk for LAST. An increasing number of reported events occur outside of the traditional hospital setting and involve non-anesthesiologists.

Transverse in-plane ultrasound-guided needle insertion into the thoracic paravertebral space is both feasible and reliable. However, paravertebral spread of contrast is highly variable with intercostal and epidural spread likely contributing significantly to the analgesic efficacy. A dual-injection technique at separate levels seems to cover more thoracic dermatomes because of greater segmental intercostal spread (rather than paravertebral spread) than a single-injection approach. Catheters are located in nonideal positions in 40% of cases using this in-plane technique.