Utility of Chest Radiography in Emergency Department Patients Presenting With Syncope

Matthew L. Wong, MD, MPH; David Chiu, MD; Nathan I Shapiro, MD, MPH; Shamai A Grossman, MD, MS

Disclosures

Western J Emerg Med. 2016;17(6):698-701. 

In This Article

Methods

Study Design and Setting

This is a secondary analysis of a prospective, observational, cohort study conducted in an urban teaching hospital with an annual ED census of 55,000 as part of the original Boston Syncope Criteria study. Syncope was defined as a sudden and transient (<5 minutes) loss of consciousness, producing a brief period of unresponsiveness and a loss of postural tone, ultimately resulting in spontaneous recovery requiring no resuscitation measures. More extensive details have been reported elsewhere.[6–7] From September 2003 to June 2006 we studied consecutive patients presenting to the ED with syncope. Institutional review board approval was obtained prior to initiation of the study.

Selection of Participants

Inclusion criteria included patients aged 18 years or older who met our definition of syncope.

Exclusion criteria were persistent altered mental status, alcohol- or illicit drug-related loss of consciousness, seizure, coma, hypoglycemia, transient loss of consciousness caused by head trauma, or near syncope. We excluded patients with near syncope, including all patients without transient loss of consciousness, due to a lack of consensus regarding the definition of this entity.

Interventions

This study was observational; thus, the treating physicians were not directed to perform specific tests or work up. CXRs were ordered solely at the discretion of the treating physicians. All treatment decisions, including the necessity of a CXR, as well as the decision to admit the patient or not was at the sole discretion of the treating physician. An abnormal CXR was defined as a radiograph with findings consistent with congestive heart failure (CHF), pneumonia or pleural effusion.

Outcome Measures

The primary outcome was the distribution of abnormal CXRs by serious adverse event. Serious adverse events were defined as death, pulmonary embolus, stroke, severe infection/sepsis, ventricular dysrhythmia, atrial dysrhythmia (including SVT [supraventricular tachycardia] and atrial fibrillation with rapid ventricular response), intracranial bleed, myocardial infarction pacemaker/implantable cardiac defibrillator placement, percutaneous coronary intervention, or surgery, blood transfusion, cardiac arrest, alteration in antidysrhythmic therapy, endoscopy with intervention, or correction of carotid stenosis. Follow up was conducted at 30 days via telephone call and medical records review. In addition to review of in-hospital and post-discharge medical records, patients were queried as to whether they had additional testing following discharge to help avoid missing results of testing done outside of our institution. Findings were considered positive if based on the discharge summary the CXR was suggestive of the etiology of the patient's syncope or contributed to an adverse event during the patient's care.

Data Collection and Processing

A trained research assistant available 16 hours per day prospectively screened patients with complaints of syncope or loss of consciousness and reviewed daily patient logs to ensure completion of documentation and to identify missed off-hour patients. Patients were identified in the ED either by research assistants or by the physician caring for that patient, although the attending physician made the final decision of whether the patient met enrollment criteria. The treating physician obtained informed consent and enrolled the patient. Approximately 50% of questionnaires were completed on initial ED evaluation, with the remainder completed shortly afterward. A study investigator or trained research assistant carried out follow-up phone calls with a structured follow-up form and medical record review at 30 days after initial presentation to the ED to determine whether they had a further testing either in hospital or after discharge.

All enrolled patients had at least one episode of syncope meeting the above definition to be eligible for enrollment. All adverse outcomes or clinical interventions, such as CPR, stroke, or cardiac arrest were noted after spontaneous recovery from the initial syncopal episodes. Outcomes were determined by inpatient diagnosis, 30-day follow-up phone call, and subsequent medical records review.

Primary Data Analysis

We queried the acquired dataset for patients who did or did not receive a CXR as part of their evaluation, as well as for whether they suffered a 30-day adverse event. Standard numerical analysis was used for reporting means and standard deviations.

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