Just the facts: brachial plexus blocks for upper extremity injuries in the emergency department.

Ultrasound-guided nerve blocks (UGNBs) are becoming a more common method for pain control in the emergency department. Specifically, brachial plexus blocks have shown promise for acute upper extremity injuries as well as an alternative to procedural sedation for glenohumeral reductions. Unfortunately, there is minimal discussion in the EM literature regarding phrenic nerve paralysis (a well-known complication from brachial plexus blocks). The anatomy of the brachial plexus, its relationship to the phrenic nerve, and why ultrasound-guided brachial plexus blocks can cause phrenic nerve paralysis and resultant respiratory impairment will be discussed. The focus on patient safety is paramount, and those with preexisting respiratory conditions, extremes of age or weight, spinal deformities, previous neck injuries, and anatomical variations are at greater risk. We put forth different block strategies for risk mitigation, including patient selection, volume and type of anesthetic, block location, postprocedural monitoring, and specific discharge instructions. Understanding the benefits and risks of UGNBs is critical for emergency physicians to provide effective pain control while ensuring optimal patient safety.

Does needle positioning with magnetic field induction improve central venous catheterization performance by novice learners?

OBJECTIVE: The novel ultrasound magnetic needle navigation technique can visualize the entire needle and identify its projected trajectory. We hypothesized that this technique increases the first-attempt success rate of central venous puncture by novice learners compared with the conventional needle navigation technique. METHODS: This prospective, randomized, controlled trial with a crossover design included 50 participants with limited prior experience in US-guided procedures. Participants were randomly assigned to novel or conventional technique groups and asked to perform central venous cannulation in a phantom task trainer. After the first successful attempt, participants were allocated to the other technique group. RESULTS: Although participants in the novel technique group had a higher first-attempt success rate than did those in the conventional technique group, this difference was not statistically significant (p = 0.17). The total number of attempts also did not significantly differ (p = 0.16). The conventional technique group had more needle redirections (p = 0.01) and a longer time to successful cannulation (p = 0.01). The number of adverse effects (p = 0.32) did not differ between groups. Participant confidence levels were higher in the novel technique group (p < 0.001). CONCLUSIONS: Magnetic needle navigation can reduce the number of needle redirections, shorten the time to successful cannulation, and increase confidence levels by novice learners for successful US-guided central venous access.

Evaluation of Soft-Tissue Hematomas With Real-Time, Contrast-Enhanced Ultrasound: A Pilot Study With Preliminary Findings.

ABSTRACT: In this study, we investigated the feasibility of using contrast-enhanced ultrasound (CEUS) to detect active hemorrhage in patients presenting with soft-tissue hematomas. Adult patients with clinically suspected, actively bleeding hematomas were prospectively enrolled. Contrast-enhanced ultrasound was used to assess for contrast extravasation. Ultrasound results were compared with those of multidetector computed tomographic (MDCT) imaging, operative findings, and clinical course. Sixteen patients (9 women, 7 men; mean age, 69 [SD, 13] years) were enrolled. Thirteen patients underwent MDCT imaging during their initial visit, and for 11, CEUS and computed tomography (CT) findings were concordant. The remaining patients had a negative CEUS study that was consistent with their clinical course. In 8 patients, CT imaging showed active extravasation (6 arterial, 1 indeterminate, 1 slow venous). Contrast-enhanced ultrasound and CT findings were concordant for all cases of arterial bleeding. For 1 patient, CEUS provided superior diagnostic information by identifying a pseudoaneurysm. The 2 discrepant patient cases had a ≥3-hour delay between CT and CEUS, and in 1 patient, CEUS was limited by body habitus. The second patient had no active bleeding identified in the operating room. Compared with CT, CEUS had a sensitivity and specificity of 75% and 100%, respectively, and positive and negative predictive values were 100% and 71%, respectively. Diagnostic accuracy was 85% in this limited study. Contrast-enhanced ultrasound is a promising alternative to MDCT in select patients and may sometimes provide superior clinical information. Limiting factors are large hematoma size, unfavorable anatomic location, and body habitus.

Precise Limb Tourniquet Arterial Occlusion Pressure Determination using Real-Time Ultrasonography and a Capacitive-Based Force Sensor.

BACKGROUND: Hemorrhage control prior to shock onset is increasingly recognized as a time-critical intervention. Although tourniquets (TQs) have been demonstrated to save lives, less is known about the physiologic parameters underlying successful TQ application beyond palpation of distal pulses. The current study directly visualized distal arterial occlusion via ultrasonography and measured associated pressure and contact force. METHODS: Fifteen tactical officers participated as live models for the study. Arterial occlusion was performed using a standard adult blood pressure (BP) cuff and a Combat Application Tourniquet Generation 7 (CAT7) TQ, applied sequentially to the left mid-bicep. Arterial flow cessation was determined by radial artery palpation and brachial artery pulsed wave doppler ultrasound (US) evaluation. Steady state maximal generated force was measured using a thin-film force sensor. RESULTS: The mean (95% CI) systolic blood pressure (SBP) required to occlude palpable distal pulse was 112.9mmHg (109-117); contact force was 23.8N [Newton] (22.0-25.6). Arterial flow was visible via US in 100% of subjects despite lack of palpable pulse. The mean (95% CI) SBP and contact force to eliminate US flow were 132mmHg (127-137) and 27.7N (25.1-30.3). The mean (95% CI) number of windlass turns to eliminate a palpable pulse was 1.3 (1.0-1.6) while 1.6 (1.2-1.9) turns were required to eliminate US flow. CONCLUSIONS: Loss of distal radial pulse does not indicate lack of arterial flow distal to upper extremity TQ. On average, an additional one-quarter windlass turn was required to eliminate distal flow. Blood pressure and force measurements derived in this study may provide data to guide future TQ designs and inexpensive, physiologically accurate TQ training models.

Real-time Ultrasound-Guided Manual Testicular Detorsion: A Case Report.

INTRODUCTION: Acute testicular torsion is a surgical emergency due to acute testicular ischemia. Manual testicular detorsion is a testis-saving, bedside therapeutic when performed correctly and in a timely fashion. This procedure is most commonly performed blindly with pain relief as the endpoint for detorsion. However, up to one-third of patients continued to show signs of residual torsion in the operating room even using pain relief as the stopping point for the procedure. CASE REPORT: We present a case demonstrating the utility of color Doppler ultrasound to confirm complete manual detorsion in a 14-year-old male with acute testicular torsion. The patient underwent 360-degree detorsion and had relief of pain; however, color Doppler demonstrated incomplete return of flow to the testis. After an additional 180-degree turn was made, color Doppler demonstrated complete return of normal vascular flow to the torsed testis. CONCLUSION: When it comes to testicular viability, timely restoration of blood flow to the testicle is of utmost importance. Manual detorsion is a non-invasive intervention that can be quickly and effectively performed at the bedside. Moreover, using color Doppler ultrasound guidance can ensure that physicians detorse in the proper direction and to completion, by providing instant visualization of restorative flow and ensuring reperfusion of the testis while awaiting definitive surgical management.

Ultrasound-Guided Great Saphenous Vein Access: Revisiting an Old Friend in a New Location.

BACKGROUND: Early recognition of difficult intravenous (i.v.) access and use of ultrasound-guided techniques prior to multiple attempts are important steps in improving patient care in the emergency department (ED). Success rates for ultrasound-guided peripheral i.v. (PIV) cannulation are affected by depth, size of target vessel, and predictability of anatomy. The great saphenous vein (GSV) in the medial distal thigh may provide an alternative site for ultrasound-guided cannulation in cases of difficult peripheral venous access. OBJECTIVES: Our objective was to determine the feasibility of ultrasound-guided GSV PIV placement as an alternative site for patients with difficult i.v. access. METHODS: Participants were prospectively enrolled from a convenience sample of patients presenting to the ED in June and July 2019. Inclusion criteria were age 18 years and older, and a history of difficult i.v. access or two unsuccessful nursing staff attempts. Ultrasound-guided access was conducted with an in-plane or out-of-plane approach on the basis of proceduralist preference. RESULTS: Twenty patients were enrolled; 1 patient withdrew consent prior to cannulation. GSV cannulation was successful in 14 (73.7%) of the 19 patients. Phlebotomy, blood transfusion, i.v. medications including norepinephrine, and i.v. computed tomography contrast medium were successfully performed via GSV access. No reported infection, thrombosis, or extravasation was identified throughout the cannulation dwell time, hospitalization, or for 72 h after discharge. CONCLUSION: Ultrasound-guided GSV PIV placement is a feasible alternative in situations of difficult i.v. access. No unforeseen complication or safety issue was identified. Blood products, medications, and contrast medium were successfully administered safely.

"Swirling right ventricular" sign as a marker of right ventricular dysfunction in two patients with submassive pulmonary embolism.

Assessing the right ventricular function in patients with submassive pulmonary embolism (PE) is pivotal when determining the appropriate treatment pathway. We describe two cases of submassive PE requiring systemic thrombolysis, in which intravenous saline contrast demonstrated a noticeable lack of forward flow in the right ventricle. This technique potentially may indicate impending right ventricular functional collapse and the need for more aggressive intervention.