Regional Anesthesia and Pain Medicine最新文献

Gastric ultrasound is a well-established point-of-care ultrasound (PoCUS) application that aids clinicians in the assessment of gastric content and risk of aspiration at the bedside. In recent years, with the increasing use of Glucagon-like-Peptide 1 (GLP-1) receptor agonists the utility of gastric PoCUS has been endorsed by several professional societies, particularly when fasting status is uncertain. However, 2%-5% of gastric ultrasound exams can yield indeterminate findings due to various reasons. In this educational article, we aim to highlight common pitfalls that can lead to misinterpretation of gastric ultrasound findings and offer troubleshooting strategies to enhance image acquisition and interpretation. Finally, we suggest alternative scanning planes that may be considered when the standard approach is not feasible or fails to provide sufficient information.

Introduction: Preclinical and clinical studies have shown enhanced analgesia when some adjuvant medications are combined with local anesthetics during peripheral nerve (PN) blockade. However, the effects of many adjuvants on individual PN fibers, that is, A-alpha/beta, A-delta, and C, remain poorly characterized.

Methods: Using ex vivo rat sciatic nerve electrophysiology, changes in action potential amplitude (AMP) and area under the curve (AUC) for A-alpha/beta, A-delta, and C fibers were used to determine the half-maximal effective concentrations (EC50) for four adjuvants (dexmedetomidine, magnesium, epinephrine, ketorolac) with and without bupivacaine. At a clinically relevant "high" concentration, each adjuvant's effects on AMP, AUC, and latency to 100% peak AMP were evaluated with and without bupivacaine, then statistically compared with control (no drug) and bupivacaine-alone conditions.

Results: EC50s for the four adjuvants were determined for some fibers: dexmedetomidine (A-alpha/beta, A-delta, C fibers), magnesium (A-delta fibers), epinephrine (C fibers), and ketorolac (A-alpha/beta and A-delta fibers). At the high concentrations, adjuvants alone produced few significant differences when compared with control, and adjuvants with bupivacaine produced few significant differences when compared with bupivacaine alone.

Discussion: Using ex vivo electrophysiology, we identified EC50s of dexmedetomidine, magnesium, epinephrine, and ketorolac for A-alpha/beta, A-delta, and/or C fiber AMP, demonstrating that these adjuvants have direct effects on PN fibers. Future investigations may benefit by testing different concentrations of adjuvants and bupivacaine in an in vivo model incorporating a broader range of time points.

Facial pain disorders, most notoriously trigeminal neuralgia, cause substantial suffering, functional impairment, disability, and impaired quality of life. However, most pain medicine practitioners have had only limited education on the evaluation, diagnosis, and treatment of facial pain. Furthermore, this limited education often contains commonly held myths about facial pain diagnosis. These myths can result in misdiagnoses that lead to ineffective medications, interventions, or surgeries and prolonged pain. Therefore, the American Society of Regional Anesthesia and Pain Medicine's Headache and Facial Pain Special Interest Group convened a multidisciplinary group of neurologists, anesthesiologists, and dentists to identify and dispel pervasive myths in facial pain diagnosis.