Hypertensive Emergency Workup
Immediately admit the patient to the ICU, establish continuous arterial blood pressure monitoring, obtain a comprehensive laboratory panel (CBC, creatinine, electrolytes, LDH, haptoglobin, troponins, urinalysis), perform ECG and fundoscopy, and initiate parenteral antihypertensive therapy targeting a 20-25% reduction in mean arterial pressure within the first hour. 1, 2
Immediate Diagnostic Evaluation
Essential Laboratory Tests
The workup must include a comprehensive panel to identify target organ damage:
- Complete blood count with hemoglobin and platelets to detect microangiopathic hemolytic anemia (evidence level B) 2
- Basic metabolic panel including creatinine, sodium, and potassium to assess renal function and electrolyte abnormalities (evidence level A) 2
- Lactate dehydrogenase (LDH) and haptoglobin to identify hemolysis in hypertensive thrombotic microangiopathy (evidence level B) 2
- Urinalysis with microscopy for proteinuria and sediment examination to detect renal damage (evidence level A) 2
- Troponins in all patients with chest pain or suspected cardiac involvement (evidence level A) 2
Organ-Specific Assessment
Cardiac evaluation:
- ECG to identify left ventricular hypertrophy, ischemia, or acute coronary syndrome 2
- Consider BNP if heart failure is suspected 2
Neurological assessment:
- Detailed neurological examination for encephalopathy, stroke, or focal deficits 1
- CT or MRI brain if neurological symptoms are present 2
Ophthalmological examination:
Renal evaluation:
- Elevated creatinine indicates acute kidney injury 2
- Significant proteinuria suggests hypertensive nephropathy 2
- Abnormal urine sediment with red blood cells or casts indicates active renal damage 2
Vascular assessment:
- CT angiography of chest/abdomen if aortic dissection is suspected based on clinical presentation 2
Critical Diagnostic Pitfalls
- Do not delay laboratory testing - immediate assessment is crucial for appropriate management (evidence level A) 2
- The absolute blood pressure value is less important than the presence of target organ damage - patients with chronic hypertension may tolerate higher pressures than previously normotensive individuals 2
- Screen for secondary hypertension causes after stabilization, as 20-40% of malignant hypertension cases have identifiable secondary causes including renal artery stenosis, pheochromocytoma, or primary aldosteronism 2
- Assess for precipitating factors including medication non-compliance (the most common trigger), sympathomimetics, cocaine, NSAIDs, steroids, immunosuppressants, and antiangiogenic therapy 2
Monitoring Requirements
- Continuous arterial blood pressure monitoring via intra-arterial line is recommended for precise titration of therapy 1, 2
- Continuous cardiac monitoring for arrhythmias and ischemic changes 1
- Serial neurological assessments to detect deterioration 1
- Frequent renal function monitoring during acute management 1
Target Organ Damage Classification
The presence of any of the following defines a hypertensive emergency requiring immediate intervention:
- Neurological: Hypertensive encephalopathy, intracranial hemorrhage, acute ischemic stroke 1, 2
- Cardiac: Acute myocardial infarction, acute left ventricular failure with pulmonary edema 1, 2
- Renal: Acute kidney injury, thrombotic microangiopathy 1, 2
- Vascular: Aortic dissection or rupture 1, 2
- Hematologic: Microangiopathic hemolytic anemia with thrombocytopenia 2
- Ophthalmologic: Grade III-IV retinopathy with papilledema, hemorrhages, or exudates 2
- Obstetric: Severe preeclampsia or eclampsia 2
Laboratory Interpretation Context
- Thrombocytopenia with elevated LDH and decreased haptoglobin indicates thrombotic microangiopathy requiring urgent management 2
- Remember that not all laboratory abnormalities are directly related to the hypertensive crisis - interpret findings in clinical context (evidence level B) 2
- Volume depletion from pressure natriuresis may occur, and intravenous saline may be needed if precipitous blood pressure falls develop 2