What is the initial workup and management for a patient with orthostatic hypotension?

Initial Workup and Management of Orthostatic Hypotension

The initial workup for orthostatic hypotension should include measuring blood pressure after 5 minutes of lying or sitting, then 1 and 3 minutes after standing, with a decrease in systolic blood pressure ≥20 mmHg or diastolic ≥10 mmHg within 3 minutes confirming the diagnosis, followed by a medication review to identify and discontinue causative agents. 1

Diagnostic Approach

Orthostatic Vital Sign Assessment

• Measure blood pressure after 5 minutes of lying or sitting, then at 1 and 3 minutes after standing 1
• Document symptoms that correlate with hypotension (dizziness, lightheadedness, blurred vision, weakness)
• Diagnostic criteria: decrease in systolic BP ≥20 mmHg or diastolic BP ≥10 mmHg within 3 minutes of standing 1, 2

Initial Evaluation

1. Review medication list for potential causes:

   • Antihypertensives
   • Opioids
   • Anticholinergics
   • Tricyclic antidepressants 1
   • Psychoactive medications 3

2. Assess for underlying medical conditions:

   • Dehydration
   • Blood loss
   • Autonomic dysfunction
   • Endocrine disorders (diabetes, adrenal insufficiency)
   • Cardiovascular disorders 2

3. Consider head-up tilt-table testing if:

   • Standard orthostatic vital signs are nondiagnostic
   • Patient cannot stand safely
   • High clinical suspicion despite normal bedside testing 2, 4

Management Algorithm

Step 1: Address Reversible Causes

• Correct volume depletion
• Discontinue or modify medications that may cause or exacerbate orthostatic hypotension 5, 3

Step 2: Non-Pharmacological Interventions

• Acute water ingestion (Class I recommendation) for temporary relief 1
• Physical counter-pressure maneuvers (leg crossing, squatting) to increase peripheral resistance (Class IIa recommendation) 1
• Compression garments, including abdominal binders and lower extremity compression stockings (Class IIa recommendation) 1
• Increased salt and fluid intake, targeting 2-3 liters daily unless contraindicated (Class IIb recommendation) 1
• Elevate head of bed during sleep 1
• Small, frequent meals to reduce post-prandial hypotension 1
• Regular exercise to prevent deconditioning 1

Step 3: Pharmacological Management

For patients with persistent symptoms despite non-pharmacological interventions:

1. First-line medications:

   • Midodrine (10 mg up to 2-4 times daily, Class IIa recommendation)
     • Alpha-1 agonist
     • Increases standing systolic BP by 15-30 mmHg at 1 hour after 10 mg dose
     • Effect persists for 2-3 hours
     • FDA-approved for symptomatic orthostatic hypotension 1, 6
   • Droxidopa (100-600 mg three times daily, Class IIa recommendation)
     • FDA-approved for neurogenic orthostatic hypotension
     • Last dose at least 4 hours before bedtime 1

2. Alternative options:

   • Fludrocortisone (0.05-0.1 mg daily, titrated to 0.1-0.3 mg daily, Class IIa recommendation)
     • Mechanism: sodium retention, vessel wall constriction
     • Note: Contraindicated in ESRD due to risk of fluid retention 1
   • Pyridostigmine and octreotide for refractory cases (Class IIb recommendation) 1

Monitoring and Follow-up

• Primary goal: minimize postural symptoms rather than restore normotension 1
• Target BP: <130/80 mmHg for most adults, <130 mmHg for ambulatory adults ≥65 years 1
• Monitor for supine hypertension, especially with pressor medications 1, 7
• Regular follow-up every 3 months once stabilized 1
• Consider referral to specialist for:
  • Suspected secondary causes
  • Refractory hypotension despite initial management
  • Hypotension with multiple cardiovascular risk factors 1

Important Clinical Considerations

• Midodrine can cause marked elevation of supine blood pressure (>200 mmHg systolic) and should be used cautiously 6
• The last dose of midodrine should not be taken later than 6 PM to avoid supine hypertension during sleep 6
• Orthostatic hypotension is associated with increased cardiovascular risk, falls, and up to 50% increase in all-cause mortality 4
• Treatment should be individualized based on symptom severity, with milder cases potentially managed with non-pharmacological measures alone 5