Novice performance of ultrasound-guided needling skills: effect of a needle guidance system.

BACKGROUND AND OBJECTIVES: Ultrasound-guided needle placement is a widely used technical skill that can be challenging to learn. The SonixGPS is a novel ultrasound needle-tracking system that has the potential to improve performance over traditional ultrasound systems. The objective of our study was to determine if the use of the SonixGPS ultrasound system improves performance of novice practitioners in ultrasound-guided needle placement compared with conventional ultrasound in the out-of-plane approach on a simulation model. METHODS: Twenty-six medical students without previous ultrasound experience were randomized into 2 groups. Each group performed 30 simulated ultrasound nerve blocks on a porcine meat tissue simulation (phantom) model. Both groups used the SonixGPS ultrasound; however, the study group had the needle-tracking system activated, whereas the control group did not. The participants were assessed for success rate, technical aspects of block performance, and certain behaviors that could compromise the quality of the block. Learning curves were developed to assess competence. RESULTS: The needle guidance group reached competence more often. This group had fewer attempts and quality-compromising behaviors than did those using conventional ultrasound. CONCLUSIONS: Use of the SonixGPS ultrasound needle guidance system improves the performance of technical needling skills of novice trainees in an ex vivo model. The place of this technology in the wider education of ultrasound-guided regional anesthesia remains to be established.

Intravenous dexamethasone and perineural dexamethasone similarly prolong the duration of analgesia after supraclavicular brachial plexus block: a randomized, triple-arm, double-blind, placebo-controlled trial.

BACKGROUND AND OBJECTIVES: Perineural dexamethasone prolongs the duration of single-injection peripheral nerve block when added to the local anesthetic solution. Postulated systemic mechanisms of action along with theoretical safety concerns have prompted the investigation of intravenous dexamethasone as an alternative, with decidedly mixed results. We aimed to confirm that addition of intravenous dexamethasone will prolong the duration of analgesia after single-injection supraclavicular block compared with conventional long-acting local anesthetic alone or in combination with perineural dexamethasone for ambulatory upper extremity surgery. METHODS: Seventy-five patients were randomized to receive supraclavicular block using 30-mL bupivacaine 0.5% alone (Control), with concomitant intravenous dexamethasone 8 mg (DexIV), or with perineural dexamethasone 8 mg (DexP). Duration of analgesia was designated as the primary outcome. To test our hypothesis, the superiority of DexIV was first compared with Control and then with DexP. Motor block duration, pain scores, opioid consumption, opioid-related side effects, patient satisfaction, and block-related complications were also analyzed. RESULTS: Twenty-five patients per group were analyzed. The duration of analgesia (mean [95% confidence interval]) was prolonged in the DexIV group(25 hours [17.6­32.4]) compared with Control (13.2 hours [11.5­15.0]; P < 0.001) but similar to the DexP group (25 hours[19.5­30.5]; P = 1). [corrected] Both DexIV and DexP had reduced pain scores, reduced postoperative opioid consumption, and improved satisfaction compared with Control. CONCLUSIONS: In a single-injection supraclavicular block with long-acting local anesthetic, the effectiveness of intravenous dexamethasone in prolonging the duration of analgesia seems similar to perineural dexamethasone.

Cumulative sum scoring for medical students.

CONTEXT: A variety of subjective techniques are used to assess clinical skills during medical training. The objective assessment of practical skill proficiency is not currently widespread. Cumulative sum charts have been used in several branches of medicine for the audit of practical procedural success. In this paper, we describe our use of cumulative sum scoring to present and determine competency in peripheral venous cannulation for medical students. METHOD: Ten medical students each performed between 50 and 65 intravenous cannulations sequentially recording their successes and failures. Cumulative sum plots were created using previously published algorithms. Modifications of the standard plot were also used to give an early warning of poor performance and to give an earlier recognition of good performance. RESULTS: The 'learning curve' modification demonstrated that all students achieved competence during the study, although many needed to perform more procedures than would usually be possible during their medical school training. The 'early warning' modification aided the early identification of practice that differed from acceptable standards. DISCUSSION: Cumulative sum scoring is an objective measure of practical procedural success and failure that can easily be used by medical students and professionals alike, to both determine competency and to facilitate the early warning of substandard practice so that appropriate training may be instigated. The principle issue affecting the utility of the technique for medical students is the number of procedures that need to be performed in order to create a meaningful plot.