Background: Syncope is a common chief complaint in the emergency department (ED) among older adults and routine laboratory testing is often a part of the work up. We assessed the frequency of abnormal laboratory results in older adults presenting to the ED with syncope
Methods: This is a secondary analysis of a prospective, observational study at 11 EDs in adults 60 years or older who presented with syncope or near syncope. We excluded patients lost to follow up. We used institutional clinical laboratory guidelines for identification of critical lab results. Abnormal ranges were determined utilizing the National Institute of Medicine and prior literature. We determined the percentage of critical, abnormal, and normal laboratory results assessed at the primary presentation for syncope.
Results: The study cohort included 3557 patients of whom 51.6% were male. 154 (4.3%) patients had at least one critical lab result, 3,080 (86.6%) patients had at least one abnormal, but no critical lab findings, and 323 (9.1%) patients had normal lab results. The most frequent abnormal lab findings were elevated glucose (72.9%), elevated BUN (44%), and elevated creatinine (28%). The most frequent critical lab tests were creatinine (2.5%), potassium (1.0%) and hematocrit (0.4%).
Conclusion: In a cohort of older adult patients presenting to the ED with syncope, although critical lab results were uncommon, abnormal lab tests were common. Routine ED lab testing in older patients may identify lab abnormalities requiring hospital admission.