Regional Anesthesia and Pain Medicine最新文献

Introduction: Patients hospitalized for headache treatment pose unique challenges to the healthcare system. Currently, there is a lack of evidence-based guidance on management. This practice advisory aims to fill this critical gap by systematically reviewing the existing literature and providing comprehensive, evidence-based recommendations for managing headache patients during hospitalization.

Methods: In February 2023, the American Society of Regional Anesthesia and Pain Medicine approved this practice advisory proposal. The steering committee selected committee members based on clinical and research expertise in the field of headache medicine. Nine questions were formulated by the committee, and each question was assigned to a group composed of 3-4 members. A systematic literature search for each question was performed in Medline, Embase, Cochrane Database of Systematic Reviews and Web of Science on June 21, 2023. The results from each search were imported into separate Covidence projects for screening, data extraction, and risk of bias assessment. Additionally, relevant systematic reviews (SR) were screened. Each group submitted a structured narrative review along with statements and recommendations based on the US Preventive Services Task Force (USPSTF) format for grading of evidence. While the USPSTF framework was used, including the language in the recommendations, the formal USPSTF methodology, including the SR with meta-analysis and summary tables with forest plots, was not followed because of low overall evidence quality. The interim draft was shared electronically with each collaborator, who was requested to vote anonymously using two rounds of the modified Delphi approach. A consensus recommendation required >75% agreement.

Results: The panel generated 12 statements and 17 recommendations, along with their strength and certainty of evidence. Following two rounds of Delphi voting, a high consensus was achieved for all statements and recommendations. Most statements received a low-to-moderate level of certainty, and all but one recommendation received grade B or C, which was consistent with the lack of randomized controlled trials supporting most of the drugs in this document.

Conclusions: This evidence-based practice advisory provides a foundational step toward standardizing inpatient headache care and highlights existing gaps in the literature that should be addressed through rigorous prospective randomized studies.

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.

Background: The mechanism by which local anesthetics spread and produce analgesia in interfascial plane blocks remains unclear. Clinical efficacy often exceeds the visible spread of injectate on imaging. This cadaveric study quantified the distribution of bupivacaine within skeletal muscle and across fascial barriers to explore diffusion as a potential contributor to interfascial plane block dynamics.

Methods: Fresh and frozen-thawed human soleus muscles were injected with a mixture of bupivacaine and methylene blue, and samples were collected along and perpendicular to fiber orientation. Fresh lower limbs were used to assess transfascial transfer across sequential crural fasciae after injection with bupivacaine, iodinated contrast, and methylene blue. The limbs were imaged with CT and samples were collected from crural compartments separated by fascial layers. Finally, simulated posteromedial quadratus lumborum block was performed in fresh cadavers, with samples harvested from the quadratus lumborum, psoas major, and diaphragm. Bupivacaine concentrations were quantified using high-performance liquid chromatography-mass spectrometry.

Results: In fresh muscle, bupivacaine exhibited an anisotropic pattern, with concentration gradients decreasing more slowly along muscle fiber orientation than in transverse direction (p=0.0008). This directional difference disappeared in frozen-thawed tissue. Across fascial barriers, bupivacaine decreased exponentially with the distance from injection site, compatible with diffusion-driven transport, whereas methylene blue and iodinated contrast were not detected beyond the injected compartments. After simulated quadratus lumborum block, bupivacaine was detected in the psoas major (0.7-487.6 µg/g), quadratus lumborum (0.2-266.1 µg/g), and diaphragm (9.0-27.3 µg/g) despite no evident methylene blue spread.

Conclusions: Low-volume injectate of bupivacaine spread anisotropically within fresh muscle and permeated fascial barriers in ways not demonstrated by methylene blue or iodinated contrast. The exponential decrease of concentrations provides evidence that diffusion contributes to local anesthetic distribution and may help explain, at least in part, the broad and occasionally disproportionate sensory coverage observed clinically with interfascial plane blocks.