Search

Background: This randomized trial compared perineural dexamethasone with combined perineural dexamethasone-dexmedetomidine for ultrasound-guided infraclavicular block. We hypothesized that the combination of perineural adjuvants would result in a longer motor block., Methods: Fifty patients undergoing upper limb surgery with ultrasound-guided infraclavicular block (using 35 mL of lidocaine 1%-bupivacaine 0.25% with epinephrine 5 µg/mL) were randomly allocated to receive perineural dexamethasone (2 mg) or combined perineural dexamethasone (2 mg)-dexmedetomidine (50 µg). After the performance of the block, a blinded observer assessed the success rate (defined as a minimal sensorimotor composite score of 14 out of 16 points at 30 min), the onset time (defined as the time required to reach a minimal composite score of 14 points) as well as the incidence of surgical anesthesia (defined as the ability to complete surgery without local infiltration, supplemental blocks, intravenous opioids or general anesthesia).Postoperatively, the blinded observer contacted patients with successful blocks to inquire about the duration of motor block, sensory block and postoperative analgesia., Results: No intergroup differences were observed in terms of success rate, onset time and surgical anesthesia. Compared with dexamethasone alone, combined dexamethasone-dexmedetomidine provided longer durations of motor block (21.5 (2.7) vs 17.0 (3.9) hours; p<0.001; 95% CI 2.6 to 6.4), sensory block (21.6 (3.6) vs 17.2 (3.6) hours; p<0.001; 95% CI 2.2 to 6.5), and postoperative analgesia (25.5 (9.4) vs 23.5 (5.6) hours; p=0.038; 95% CI 1.0 to 7.7)., Conclusion: Compared with perineural dexamethasone (2 mg) alone, combined perineural dexamethasone (2 mg)-dexmedetomidine (50 µg) results in longer durations of sensorimotor block and analgesia. Further studies are required to determine the optimal dosing combination for dexamethasone-dexmedetomidine., Trial Registration Number: ClinicalTrials.gov identifier: NCT04875039., Competing Interests: Competing interests: None declared., (© American Society of Regional Anesthesia & Pain Medicine 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: During total hip arthroplasty (THA) using the direct anterior approach, orthopaedic surgeons can identify all anatomical landmarks required for pericapsular nerve group (PENG) blocks and carry out the latter under direct vision. This cadaveric study investigated the success of surgeon-performed PENG block. Success was defined as dye staining of the articular branches of the femoral and accessory obturator nerves., Methods: 11 cadavers (18 hip specimens) were included in the current study. To simulate THA in live patients, an orthopaedic surgeon inserted trial prostheses using the direct anterior approach. Subsequently, a block needle was advanced until contact with the bone (between the anterior inferior iliac spine and iliopubic eminence). 20 mL of 0.1% methylene blue was injected. Cadavers were then dissected to document the presence and dye staining of the femoral, lateral femoral cutaneous, obturator and accessory obturator nerves as well as the articular branches of the femoral, obturator and accessory obturator nerves., Results: Methylene blue stained the articular branches of the femoral nerve and the articular branches of the accessory obturator nerve (when present) in all hip specimens. Therefore, surgical PENG block achieved a 100% success rate. Dye stained the femoral and obturator nerve in one (5.6%) and two (11.1%) hip specimens, respectively. No dye staining was observed over the accessory obturator nerve in the pelvis nor the lateral femoral cutaneous nerve., Conclusion: Surgeon-performed PENG block during direct anterior THA reliably targets the articular branches of the femoral and accessory obturator nerves. Future trials are required to compare surgeon-performed PENG block with anaesthesiologist-performed, ultrasound-guided PENG block, and surgeon-performed periarticular local anaesthetic infiltration., Competing Interests: Competing interests: None declared., (© American Society of Regional Anesthesia & Pain Medicine 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: This cadaveric study investigated the innervations of the clavicle and clavicular joints (ie, sternoclavicular and acromioclavicular joints)., Methods: Twenty cadavers (40 clavicles) were dissected. A skin incision was made to permit exposure of the posterior cervical triangle and infraclavicular fossa. The platysma, sternocleidomastoid, and trapezius muscles were cleaned in order to identify the supraclavicular nerves. Subsequently, the suprascapular and subclavian nerves were localized after removal of the prevertebral layer of the deep cervical fascia. In the infraclavicular region, the pectoralis major and minor muscles were retracted laterally in order to visualize the lateral pectoral nerve. The contribution of all these nerves to the clavicular bone and joints were recorded., Results: Along their entire length, all clavicular specimens received contributions from the supraclavicular nerves. The latter innervated the cephalad and ventral aspects of the clavicular bone. The caudal and dorsal aspects of the clavicle were innervated by the subclavian nerve (middle and medial thirds). The lateral pectoral nerve supplied the caudad aspect of the clavicle (middle and lateral thirds). The sternoclavicular joint derived its innervation solely from the supraclavicular nerves whereas the acromioclavicular joint was supplied by the supraclavicular and lateral pectoral nerves., Conclusion: The clavicle and clavicular joints are innervated by the subclavian, lateral pectoral, and supraclavicular nerves. Clinical trials are required to determine the relative importance and functional contribution of each nerve., Competing Interests: Competing interests: None declared., (© American Society of Regional Anesthesia & Pain Medicine 2021. No commercial re-use. See rights and permissions. Published by BMJ.)