Regional anesthesia and pain medicine
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Reg Anesth Pain Med · May 2017
ReviewReview of Sympathetic Blocks: Anatomy, Sonoanatomy, Evidence, and Techniques.
The autonomic nervous system is composed of the sympathetic and parasympathetic nervous systems. The sympathetic nervous system is implicated in situations involving emergent action by the body and additionally plays a role in mediating pain states and pathologies in the body. Painful conditions thought to have a sympathetically mediated component may respond to blockade of the corresponding sympathetic fibers. ⋯ Although initially injected using landmark-based techniques, fluoroscopy and more recently ultrasound imaging have allowed greater visualization and facilitated injections of these structures. In addition to treating painful conditions, sympathetic blockade has been used to improve perfusion, treat angina, and even suppress posttraumatic stress disorder symptoms. This review explores the anatomy, sonoanatomy, and evidence supporting these injections and focuses on ultrasound-guided/assisted technique for the performance of these blocks.
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Reg Anesth Pain Med · May 2017
Review Meta Analysis Comparative StudyPerineural Versus Intravenous Dexamethasone as an Adjuvant for Peripheral Nerve Blocks: A Systematic Review and Meta-Analysis.
Dexamethasone is a useful adjuvant in regional anesthesia that is used to prolong the duration of analgesia for peripheral nerve blocks. Recent randomized controlled trials (RCTs) have demonstrated conflicting results as to whether perineural versus intravenous (IV) administration is superior in this regard, and the perineural use of dexamethasone remains off-label. Therefore, we sought to perform a systematic review and meta-analysis of RCTs. ⋯ Perineural dexamethasone prolongs the duration of analgesia across the RCTs included in our meta-analysis. The magnitude of effect of 3.77 hours raises the question as to whether perineural dexamethasone should be administered routinely over its IV counterpart-or reserved for selected patients where such prolongation would be clinically important.
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Reg Anesth Pain Med · May 2017
A Cadaveric Study of Ultrasound-Guided Subpectineal Injectate Spread Around the Obturator Nerve and Its Hip Articular Branches.
The femoral and obturator nerves are assumed to account for the primary nociceptive innervation of the hip joint capsule. The fascia iliaca compartment block and the so-called 3-in-1-block have been used in patients with hip fracture based on a presumption that local anesthetic spreads to anesthetize both the femoral and the obturator nerves. Evidence demonstrates that this presumption is unfounded, and knowledge about the analgesic effect of obturator nerve blockade in hip fracture patients presurgically is thus nonexistent. The objectives of this cadaveric study were to investigate the proximal spread of the injectate resulting from the administration of an ultrasound-guided obturator nerve block and to evaluate the spread around the obturator nerve branches to the hip joint capsule. ⋯ In cadavers, injection of 15 mL of methylene blue into the interfascial plane between the pectineus and the external obturator muscle effectively spreads proximally to reach the obturator canal, as well as the obturator nerve branches to the hip joint capsule and the accessory obturator nerve.
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Reg Anesth Pain Med · May 2017
Randomized Controlled Trial Comparative StudyA Double-Blind Randomized Comparison of Continuous Interscalene, Supraclavicular, and Suprascapular Blocks for Total Shoulder Arthroplasty.
Continuous brachial plexus blocks at the interscalene level are associated with known diaphragm dysfunction from phrenic nerve paresis. More distal blocks along the brachial plexus may provide postsurgical analgesia while potentially having less effect on diaphragm function. Continuous interscalene, continuous supraclavicular, and continuous suprascapular nerve blocks were evaluated for respiratory function and analgesia after total shoulder arthroplasty. ⋯ A continuous suprascapular block may be a useful analgesic alternative to the interscalene or supraclavicular approaches when the preservation of lung function is a priority after shoulder replacement surgery.