Matthew J. Meunier

Ultrasound Guidance Versus Electrical Stimulation for Infraclavicular Brachial Plexus Perineural Catheter Insertion

Objective. Electrical stimulation (ES)‐ and ultrasound‐guided placement techniques have been described for infraclavicular brachial plexus perineural catheters but to our knowledge have never been previously compared in a randomized fashion, leaving the optimal method undetermined. We tested the hypothesis that infraclavicular catheters placed via ultrasound guidance alone require less time for placement and produce equivalent results compared with catheters placed solely via ES. Methods. Preoperatively, patients receiving an infraclavicular perineural catheter for distal upper extremity surgery were randomly assigned to either ES with a stimulating catheter or ultrasound guidance with a nonstimulating catheter. The primary outcome was the catheter insertion duration (minutes) starting when the ultrasound transducer (ultrasound group) or catheter placement needle (stimulation group) first touched the patient and ending when the catheter placement needle was removed after catheter insertion. Results. Perineural catheters placed with ultrasound guidance took a median (10th–90th percentile) of 9.0 (6.0–13.2) minutes compared with 15.0 (4.9–30.0) minutes for stimulation (P < .01). All ultrasound‐guided catheters were successfully placed according to the protocol (n = 20) versus 70% in the stimulation group (n = 20; P < .01). All ultrasound‐guided catheters resulted in a successful surgical block, whereas 2 catheters placed by stimulation failed to result in surgical anesthesia. Six catheters (30%) placed via stimulation resulted in vascular punctures compared with none in the ultrasound group (P < .01). Procedure‐related pain scores were similar between groups (P = .34). Conclusions. Placement of infraclavicular perineural catheters takes less time, is more often successful, and results in fewer inadvertent vascular punctures when using ultrasound guidance compared with ES.

A randomized comparison of infraclavicular and supraclavicular continuous peripheral nerve blocks for postoperative analgesia.

Background: Although the efficacy of single-injection supraclavicular nerve blocks is well established, no controlled study of continuous supraclavicular blocks is available, and their relative risks and benefits remain unknown. In contrast, the analgesia provided by continuous infraclavicular nerve blocks has been validated in randomized controlled trials. We therefore compared supraclavicular with infraclavicular perineural local anesthetic infusion following distal upper-extremity surgery. Methods: Preoperatively, subjects were randomly assigned to receive a brachial plexus perineural catheter in either the infraclavicular or supraclavicular location using an ultrasound-guided nonstimulating catheter technique. Postoperatively, subjects were discharged home with a portable pump (400-mL reservoir) infusing 0.2% ropivacaine (basal rate of 8 mL/hr; 4-mL bolus dose; 30-min lockout interval). Subjects were followed up by telephone on an outpatient basis. The primary outcome was the average pain score on the day after surgery. Results: Sixty subjects were enrolled, with 31 and 29 randomized to receive an infraclavicular and supraclavicular catheter, respectively. All perineural catheters were successfully placed per protocol. Because of protocol violations and missing data, an intention-to-treat analysis was not used; rather, only subjects with catheters in situ and whom we were able to contact were included in the analyses. The day after surgery, subjects in the infraclavicular group reported average pain as median of 2.0 (10th-90th percentiles, 0.5-6.0) compared with 4.0 (10th-90th percentiles, 0.6-7.7) in the supraclavicular group (P = 0.025). Similarly, least pain scores (numeric rating scale) on postoperative day 1 were lower in the infraclavicular group compared with the supraclavicular group (0.5 [10th-90th percentiles, 0.0-3.5] vs 2.0 [10th-90th percentiles, 0.0-4.7], respectively; P = 0.040). Subjects in the infraclavicular group required less rescue oral analgesic (oxycodone, in milligrams) for breakthrough pain in the 18 to 24 hrs after surgery compared with the supraclavicular group (0.0 [10th-90th percentiles, 0.0-5.0] vs 5.0 [10th-90th percentiles, 0.0-15.0], respectively; P = 0.048). There were no statistically significant differences in other secondary outcomes. Conclusions: A local anesthetic infusion via an infraclavicular perineural catheter provides superior analgesia compared with a supraclavicular perineural catheter.

A Trainee-Based Randomized Comparison of Stimulating Interscalene Perineural Catheters With a New Technique Using Ultrasound Guidance Alone

Objective. Compared to the well‐established stimulating catheter technique, the use of ultrasound guidance alone for interscalene perineural catheter insertion is a recent development and has not yet been examined in a randomized fashion. We hypothesized that an ultrasound‐guided technique would require less time and produce equivalent results compared to electrical stimulation (ES) when trainees attempt interscalene perineural catheter placement. Methods. Preoperatively, patients receiving an interscalene perineural catheter for shoulder surgery were randomly assigned to an insertion protocol using either ultrasound guidance with a nonstimulating catheter or ES with a stimulating catheter. The primary outcome was the procedural duration (in minutes), starting when the ultrasound probe (ultrasound group) or catheter insertion needle (ES group) first touched the patient and ending when the catheter insertion needle was removed after catheter insertion. Results. All ultrasound‐guided catheters (n = 20) were placed successfully and resulted in surgical anesthesia versus 85% of ES‐guided catheters (n = 20; P = .231). Perineural catheters placed by ultrasound (n = 20) took a median (10th–90th percentiles) of 8.0 (5.0–15.5) minutes compared to 14.0 (5.0–30.0) minutes for ES (n = 20; P = .022). All catheters placed according to the protocol in both treatment groups resulted in a successful nerve block; however, 1 patient in the ES group had local anesthetic spread to the epidural space. There was 1 vascular puncture using ultrasound guidance compared to 5 in the ES‐guided catheter group (P = .182). Conclusions. Trainees using a new ultrasound‐guided technique can place inter‐scalene perineural catheters in less time compared to a well‐documented technique using ES with a stimulating catheter and can produce equivalent results.

QUANTIFICATION OF PARTIAL OR COMPLETE A4 PULLEY RELEASE WITH FDP REPAIR IN CADAVERIC TENDONS

PURPOSE Repair of a lacerated flexor digitorum profundus (FDP) tendon underneath or just distal to the A4 pulley can be technically challenging, and success can be confounded by tendon triggering and scarring to the pulley. The purpose of this study was to quantify the effect of partial and complete A4 pulley release in the context of a lacerated and repaired FDP tendon just distal to the A4 pulley. METHODS Tendon biomechanics were tested in 6 cadaveric hands secured to a rigid frame, permitting measurement of tendon excursion, tendon force, and finger range of motion. After control testing, each finger had laceration and repair of the FDP tendon at the distal margin of the A4 pulley using a 6-strand core suture technique and epitendinous repair. Testing was then repeated after the following interventions: (1) intact A4 pulley, (2) release of the distal half of the A4 pulley, (3) complete release of the A4 pulley, and (4) continued proximal release of the sheath to the distal edge of A2 (release of C2, A3, and C1 pulleys). Release of the pulleys was performed by incision; no tissue was removed from the specimens. RESULTS From full extension to full flexion, average FDP tendon excursion for all intact digits was 37.9 ± 1.5 mm, and tendon repair resulted in average tendon shortening of 1.6 ± 0.4 mm. Flexion lag increased from <1 mm to >4 mm with venting of the A4 pulley, complete A4 release, and proximal sheath release, respectively. Compared to the intact state, repair of the tendon with an intact A4 pulley, release of half the A4 pulley, complete A4 release, and proximal sheath release resulted in percentage increases in work of flexion of 11.5 ± 3.1%, 0.83 ± 2.8%, 2.6 ± 2.4%, and 3.25 ± 2.2%, respectively. CONCLUSIONS After FDP laceration and repair in the region of the A4 pulley, work of flexion did not increase by more than 3% from control conditions after partial or complete A4 pulley release, and work of flexion was significantly less than that achieved by performing a repair and leaving the A4 pulley intact.

High-Pressure Injection Injury Caused by Electronic Cigarette Explosion

Case: Electronic cigarettes are an increasingly popular and poorly regulated alternative to traditional cigarettes that deliver nicotine and other aerosolized substances to the user via a battery-powered atomizer. We report a case in which an electronic cigarette explosion resulted in a high-pressure injection injury of the finger. Conclusion: Explosions involving electronic cigarettes and similar handheld products should be treated as high-pressure injection injuries until proven otherwise. Radiographs are indispensable in the workup of these injuries. Because the true content of injected material cannot be determined with certainty, we recommend immediate surgical debridement, intravenous antibiotics, and close follow-up to observe the evolution of the injury.

Acute short radiolunate ligament rupture in a rock climber

We report the occurrence of a short radiolunate ligament rupture in a rock climber. To our knowledge, an isolated traumatic rupture of this ligament has not been described in the literature, and awareness of this entity allows initiation of therapy. The magnetic resonance imaging and ultrasound appearances are reviewed and the mechanism of injury is discussed.