Introduction: Laboratory and radiographic studies are often required by psychiatric services prior to admitting emergency patients who are otherwise deemed medically stable. Such testing may represent an unnecessary expense that prolongs emergency department stays without significantly improving care. This study determines the prevalence of such testing and how often it leads to changes in care.

Methods: We prospectively tracked laboratory testing among psychiatric patients presenting to the emergency departments of two academic tertiary care facilities. For each visit we determined whether laboratory or radiographic studies were ordered, and whether the examination was conducted at the request of the emergency physician as part of a medical screening examination or requested by the psychiatry service. We then determined if this testing changed patient disposition.

Results: Our study enrolled 598 patients. Of these, emergency physicians ordered testing as a part of medical screening on 155 patients (25.9%). We found the psychiatry service ordered laboratory or radiographic studies for 191 of 434 patients (44.0%) who emergency physicians determined did not require ancillary testing for medical clearance. Of these 191 patients, only one (0.5%; 95% Confidence Interval: 0.01% - 2.9%) had an abnormal result that led to a change in disposition. Total Medicare reimbursement rates for the additional ancillary testing in this study was $37,682.

Conclusion: Ancillary testing beyond what is required for medical clearance of psychiatric emergency patients rarely alters care. Policies that require panels of testing prior to psychiatric admission are costly and appear to be unnecessary. [West J Emerg Med 2012;13(5):388-393.]