Last updated 1/1/25
You evaluate a patient with a known history of schizophrenia who presents with auditory hallucinations in the context of medication non-compliance and has had multiple similar presentations in the past. The psychiatric ER at your hospital has agreed to accept the patient for admission, but insists on obtaining a full set of labs before transfer. However, the patient adamantly refuses to have their blood drawn…
In the ED, is obtaining routine lab testing for psychiatric patients prior to admission to a psychiatric service supported by evidence?
Current Guideline Recommendations
The American Association for Emergency Psychiatry (AAEP) recommends against routine laboratory studies in patients with an established psychiatric history who have no medical complaints, no physical examination findings, and stable vital signs.
- AAEP Task Force on Medical Clearance of Adults Part I: Introduction, Review and Evidence-Based Guidelines (PMC 🔗)
- AAEP Task Force on Medical Clearance of Adult Psychiatric Patients. Part II: Controversies over Medical Assessment, and Consensus Recommendations (PMC 🔗)
Similarly, the American College of Emergency Physicians (ACEP) advises that routine laboratory testing for all patients presenting with psychiatric complaints is not recommended, and testing should be guided by the medical history, previous psychiatric diagnoses, and physician examination.
- 2017 Clinical Policy: Critical Issues in the Diagnosis and Management of the Adult Psychiatric Patient in the Emergency Department (Annals of Emergency Med 🔗)
- 2006 Clinical Policy: Critical Issues in the Diagnosis and Management of the Adult Psychiatric Patient in the Emergency Department (Annals of Emergency Med 🔗)
The Evidence
Existing evidence demonstrates that routine laboratory tests for psychiatric patients being medically cleared for psychiatric admission have low yield.
The following FOAMed posts provide a breakdown on this evidence and outline the importance on history and physical in medical screening and avoiding common pitfalls.
- BestBets: Medical screening of patients requiring psychiatric admission in the ED (2014)
- CanadiEM: What is required for ‘medical clearance’ before referral to the psychiatry service? (2015)
- EM Cases: Medical Clearance of the Psychiatric Patient (2016)
- emDocs: Medical Clearance of Psychiatric Patients: Pearls & Pitfalls (2015)
- emDocs: ToxCard: UDS – Its Utilization Demands Scrutiny (2021)
- First10EM: Routine laboratory testing is not required prior to admission of psychiatric patients (2020)
A handful of studies mentioned in the above posts:
Study | Study Type | Results |
Protocolized Laboratory Screening for the Medical Clearance of Psychiatric Patients in the Emergency Department: A Systematic Review 2018 (🔗 Link) | Systematic review
n = 629 | Prevalence of clinically significant lab results were low (0.0%–0.4%). |
Utility of Investigations, History, and Physical Examination in "Medical Clearance" of Psychiatric Patients: A Meta-Analysis (🔗 Link) | Meta Analysis -
25 cross sectional studies | Lab investigations had low yield (1.1%) whereas history and physical had higher yield (15.6%, 14.9% respectively) |
Medical clearance of the psychiatric patient in the emergency department 2012 (🔗 Link) | Retrospective Chart Review
n = 502 | 1 chart (0.2%) yielded significant labwork (AG + hyperglycemia) but that patient also presented with fever and tachycardia. Reliability of patient self-reported drug use and alcohol use had sensitivities of 92% and 96% respectively. |
Value of mandatory screening studies in emergency department patients cleared for psychiatric admission 2012(🔗 Link) | Prospective
n=598 | 1 patient (0.5%) had results that changed disposition (positive tylenol level). Not disclosed if this would’ve been diagnosed via history and physical. |
Medical clearance and screening of psychiatric patients in the emergency department 2008 (🔗 Link) | Retrospective, observational
n = 345 | History had a 94% sensitivity for identifying medical issues while exam, vitals, and lab testing had sensitivities of 51%, 17% and 20% respectively. |
Routine laboratory testing to evaluate for medical illness in psychiatric patients in the emergency department is largely unrevealing 2009 (🔗 Link) | Prospective
n = 375 | 4 patients had abnormal lab findings that were not obvious clinically (1.4%), which ended up being 4 false positive urine cultures. |
Routine Laboratory Screening for Acetaminophen and Salicylate Ingestion in Preadmission Psychiatric Patients Is Unnecessary 2021 (🔗 Link) | Retrospective
n = 17,000 | Out of 17,000 patient encounters in which routine acetaminophen or salicylate levels were sent, there were no cases of toxicity. |
Consider lab screenings for following:
- Adult patients with no previously diagnosed psychiatric disorder presenting with a primary psychiatric complaint
- Elderly patients presenting with psychiatric complaints
- Patients with abnormal vital signs, delirium, altered cognition, or abnormal physical exam findings
- Visual or tactile hallucinations
- Those with a known or suspected co-morbid condition
Conclusion
In summary, the current consensus in the medical literature indicates that routine laboratory tests for known psychiatric patients being medically cleared for psychiatric admission are generally not recommended, and clinical evaluation should be guided by history and physical examination.