Point-of-Care Ultrasound in the Emergency Department Evaluation of Syncope

A Randomized, Prospective Study on Point-of-Care Focused Cardiac Ultrasound in Patients Presenting to the Emergency Department With Syncope

The purpose of this study is to determine whether point-of-care (bedside) ultrasound assists physicians in the evaluation and management of patients with syncope.

Syncope is one of the more common presentations to the Emergency Department, representing between 1.2-1.5% of all evaluated patients and up to 6% of admissions. Due to an often broad and overlapping differential diagnosis, syncope represents a disease entity that often requires extensive workup. This typically involves laboratory tests, EKGs, x-rays, computed tomography, or other studies that are costly, time-consuming, and, in the case of diagnostic imaging, frequently involves ionizing radiation. Yet, despite extensive testing, an exact diagnosis is not made in up to 50% of cases. Cardiac causes of syncope include myocardial infarction, pericardial effusion, volume depletion, arrhythmia, among other entities, many of which are life threatening. Echocardiography (cardiac ultrasound) has been used for inpatient syncope evaluations for several decades. In the Emergency Department, echocardiography is currently being used at the point-of-care (POC) in a limited and focused approach to a variety of conditions. However, POC ultrasound has never been systematically evaluated as a diagnostic or prognostic tool specifically for syncope in the Emergency Department. We aim to determine if an ultrasound-based protocol is effective as an adjunct in the evaluation of syncope. Our research study will examine the utility of POC ultrasound in the diagnosis, imaging and laboratory utilization, and prognosis of syncope in the Emergency Department.

A point-of-care ultrasound will be performed during the initial evaluation of the patient after randomization (Defined as Time 0)

Performance of a focused cardiac ultrasound including a qualitative assessment of left ventricular function, pericardial effusion, right ventricular strain, proximal ascending aortic diameter, and inferior vena cava size and collapsibility

Time at which an admit or discharge order is placed within the electronic medical record (estimated 2-3 hours)

At onset of therapeutic interventions including but not limited to intravenous fluids and medications (estimated time frame 0 - 6 hours)

At onset of clinical procedures including but not limited to central line placement, pericardiocentesis, thoracentesis, etc. (estimated time frame 0-6 hours)

Other imaging studies to included radiographs, additional point-of-care ultrasound, computed tomography, etc.

Adverse outcome defined as death, myocardial infarction, arrhythmia, pulmonary embolism, stroke, subarachnoid hemorrhage, significant hemorrhage, or any condition causing a return ED visit and hospitalization for a related event.

Inclusion Criteria: 18 years and older presenting to the ED with acute syncope (defined as transient loss of consciousness) or near syncope (sensation of impending but not actual loss of consciousness) as a reason for ED visit. Exclusion Criteria: persistent altered mental status alcohol or illicit drug-related loss of consciousness definite seizure, and transient loss of consciousness caused by head trauma.

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