A Randomized Controlled Trial of Ultrasound Versus Nerve Stimulator Guidance for Axillary Brachial Plexus Block.

BACKGROUND: Ultrasound-guided techniques improve outcomes in regional anesthesia when compared with traditional techniques; however, this assertion has not been studied with novices. The primary objective of this study was to compare sensory and motor block after axillary brachial plexus block when performed by novice trainees allocated to an ultrasound- or nerve-stimulator-guided group. A secondary objective was to compare the rates of skill acquisition between the 2 groups. METHODS: This study was a prospective, randomized, observer-blinded, 2-arm controlled trial. Anesthesia trainees participating in this trial were novices to axillary brachial plexus block and sonography. All trainee participants underwent a standardized training program. The primary outcome was combined sensory and motor block in the relevant territories 30 minutes after completion of block. A global rating scale was used to assess trainee block performance. RESULTS: The study was ceased after 12 trainees completed 153 blocks. There was no difference between groups in combined motor/sensory score (P = 0.28) or as a function of block number (P = 0.38). There was no difference in onset between groups (P = 0.38). In both groups, there was an increase in the global rating scale score (P < 0.0001) and reduced preblock survey and block performance times (P = 0.001) with experience. CONCLUSIONS: We were unable to demonstrate a difference in the efficacy of axillary brachial plexus block performed by novices when ultrasound guidance was compared with a nerve stimulator technique. There was evidence of similarly improved clinical performance of novices in both groups.

Preliminary results of the Australasian Regional Anaesthesia Collaboration: a prospective audit of more than 7000 peripheral nerve and plexus blocks for neurologic and other complications.

BACKGROUND AND OBJECTIVES: Peripheral nerve blockade is associated with excellent patient outcomes after surgery; however, neurologic and other complications can be devastating for the patient. This article reports the development and preliminary results of a multicenter audit describing the quality and safety of peripheral nerve blockade. METHODS: From January 2006 to May 2008, patients who received peripheral nerve blockade had data relating to efficacy and complications entered into databases. All patients who received nerve blocks performed by all anesthetists during each hospital's contributing period were included. Patients were followed up by phone to detect potential neurologic complications. The timing of follow-up was either at 7 to 10 days or 6 weeks postoperatively, depending on practice location and time period. Late neurologic deficits were defined as a new onset of sensory and/or motor deficit consistent with a nerve/plexus distribution without other identifiable cause, and one of the following: electrophysiologic evidence of nerve damage, new neurologic signs, new onset of neuropathic pain in a nerve distribution area, paresthesia in relevant nerve/plexus distribution area. RESULTS: A total of 6950 patients received 8189 peripheral nerve or plexus blocks. Of the 6950 patients, 6069 patients were successfully followed up. In these 6069 patients, there were a total of 7156 blocks forming the denominator for late neurologic complications. Thirty patients (0.5%) had clinical features requiring referral for neurologic assessment. Three of the 30 patients had a block-related nerve injury, giving an incidence of 0.4 per 1000 blocks (95% confidence interval, 0.08-1.1:1000). The incidence of systemic local anesthetic toxicity was 0.98 per 1000 blocks (95% confidence interval, 0.42-1.9:1000). CONCLUSIONS: These results indicate that the incidence of serious complications after peripheral nerve blockade is uncommon and that the origin of neurologic symptoms/signs in the postoperative period is most likely to be unrelated to nerve blockade.

Ultrasound-guided midthigh sciatic nerve block-a clinical and anatomical study.

BACKGROUND AND OBJECTIVES: Ultrasound-guided sciatic nerve block is a relatively new regional anesthesia technique with few descriptions in the literature. The objective of this study was to assess the ease with which the sciatic nerve could be imaged in the midthigh region using ultrasound and to describe the anatomy surrounding the sciatic nerve at this location. METHODS: In this prospective observational study, 40 patients scheduled for surgery where sciatic nerve block was indicated were scanned between the gluteal and the popliteal regions using an ultrasound machine (Vivid-i, GE Healthcare, Chalfont St. Giles, Bucks, UK). Patients then received real time ultrasound-guided sciatic nerve block. Validation of the ultrasound image of the sciatic nerve was achieved using nerve stimulation. Description and confirmation of the anatomy surrounding the sciatic nerve was based on a review of anatomical texts and an anatomical study on 5 unembalmed cadavers. RESULTS: The sciatic nerve was identified with ultrasound and its image validated using nerve stimulation in 38 of 40 patients (95%). In 15 patients (37.5%) nerve stimulation was required to confirm identification of the sciatic nerve. Surrounding muscles (biceps femoris, vastus lateralis, and adductor magnus) and fascial planes (lateral intermuscular septum) were identified as sonographic landmarks and were confirmed in the anatomical study. CONCLUSIONS: Ultrasonic identification of the sciatic nerve at the midthigh level can be achieved; however, in this study, 37.5% of patients required nerve stimulation to confirm its sonographic appearance. Target nerve localization and the subsequent performance of the sciatic nerve block may be enhanced by recognition of surrounding muscular and fascial structures which were also identified using ultrasound.