What is the appropriate emergency department workup for a hypertensive emergency?

Emergency Department Workup for Hypertensive Emergency

The ED workup for hypertensive emergency must focus on identifying acute target-organ damage through fundoscopy, ECG, laboratory assessment for thrombotic microangiopathy, and targeted imaging based on clinical presentation 1.

Essential Initial Workup (All Patients)

The following tests should be performed immediately when hypertensive emergency is suspected:

Laboratory Analysis

• Complete blood count: Hemoglobin and platelet count to assess for thrombotic microangiopathy (TMA)
• Metabolic panel: Creatinine, sodium, potassium
• Hemolysis markers: Lactate dehydrogenase (LDH) and haptoglobin (critical for TMA diagnosis)
• Urinalysis: Quantitative protein measurement and urine sediment examination for erythrocytes, leukocytes, cylinders, and casts 1

Mandatory Diagnostic Studies

• ECG: To detect ischemia, arrhythmias, or left ventricular hypertrophy
• Fundoscopy: Essential to identify advanced retinopathy (flame-shaped hemorrhages, cotton wool spots, papilledema) which defines malignant hypertension 1

Critical caveat: The 2026 ESH-URGEM registry revealed that fundoscopy and albuminuria testing are rarely performed in practice despite guideline recommendations—this represents a major quality gap that must be addressed 2.

Clinical Context-Driven Additional Testing

The type of suspected organ damage determines additional workup:

Cardiac Presentations

• Troponin-T, CK, CK-MB: If coronary ischemia or acute coronary syndrome suspected
• Chest X-ray or point-of-care ultrasound: To differentiate cardiogenic pulmonary edema from non-cardiac causes
• Transthoracic echocardiography: For cardiac structure and function assessment 1

Neurological Presentations

• CT brain: Mandatory to exclude intracranial hemorrhage before diagnosing hypertensive encephalopathy
• MRI with FLAIR imaging: Can confirm posterior reversible encephalopathy syndrome (PRES) showing characteristic white matter lesions in posterior brain regions 1

Important distinction: Focal neurological deficits are rare in hypertensive encephalopathy and should raise suspicion for hemorrhagic or ischemic stroke rather than encephalopathy 1.

Vascular Presentations

• CT angiography of thorax and abdomen: When acute aortic dissection suspected
• Blood pressure measurement in both arms and lower limb: To detect pressure differences indicating aortic dissection 1

Renal Presentations

• Peripheral blood smear: For schistocyte assessment when TMA suspected
• Renal ultrasound: To evaluate for postrenal obstruction, kidney size, and left-to-right differences 1

Distinguishing Emergency from Urgency

The presence or absence of acute target-organ damage is the sole determinant—not the blood pressure number itself 1. The rate of BP increase matters more than absolute values 1.

Key Target Organs to Assess

1. Retina: Advanced retinopathy (Grade III/IV)
2. Heart: Acute coronary syndrome, cardiogenic pulmonary edema
3. Brain: Encephalopathy, stroke, intracranial hemorrhage
4. Kidneys: Acute renal failure, TMA
5. Large arteries: Aortic dissection 1

History and Physical Examination Focus

Critical History Elements

• Emergency symptoms: Headache, visual disturbances, chest pain, dyspnea, focal or generalized neurological symptoms
• Medication adherence: Non-adherence is a frequent contributor
• Drug use: Steroids, NSAIDs, cyclosporin, sympathomimetics, cocaine, anti-angiogenic therapy
• Secondary causes: Kidney disease, renal artery stenosis 1

Physical Examination Priorities

• Cardiovascular assessment: Including bilateral arm and leg BP measurements
• Neurological examination: Somnolence, lethargy, seizures, cortical blindness may precede loss of consciousness in encephalopathy
• Serial BP measurements: BP often falls spontaneously without treatment—repeated measurements over time are essential 1

Common Pitfalls

Do not assume hypertensive emergency based solely on BP elevation. Approximately 50% of patients presenting with suspected hypertensive emergency lack acute organ damage and can be managed with oral medications and brief observation 1. Conversely, the registry data show that only 18.9% of true hypertensive emergencies were appropriately admitted to intensive or coronary care units, indicating significant underrecognition 2.