Frequency of Abnormal and Critical Laboratory Results in Older Patients Presenting to the Emergency Department With Syncope.

: Syncope is a common and costly chief complaint among patients presenting to the emergency department (ED), accounting for 740,000 ED visits annually with an estimated annual cost of $2.4 billion per year in the United States.1,2 Syncope presents a diagnostic dilemma for clinicians in the ED since differentiating serious and benign causes of syncope can be challenging, particularly in the older adult. Routine laboratory testing with complete blood count (CBC) and basic metabolic panel (BMP) is commonly ordered for patients presenting to the ED with syncope.