Orthostatic Hypotension
Orthostatic hypotension represents a significant drop in blood pressure upon standing, often observed in elderly patients. It's clinically marked by a decrease in systolic blood pressure by at least 20mm Hg or diastolic blood pressure by 10mm Hg within three minutes of standing. This condition highlights a failure in the body's complex regulatory system to compensate for gravity-induced blood pressure reductions.
Symptoms include:
- Lightheadedness
- Disequilibrium
- Blurred vision or “browning-out”
- Weakness
- Fatigue
- Cognitive impairment
- Syncope (fainting)
Improvement is typically seen when returning to sitting, lying down, or standing with support.
Causes of Orthostatic Hypotension
Orthostatic hypotension can stem from neurogenic and non-neurogenic origins:
Neurogenic causes:
- Peripheral neuropathy (e.g., diabetes, autoimmune diseases)
- Parkinson’s disease
- Multiple system atrophy
- Pure autonomic failure
- Lewy body dementia
- Multiple sclerosis
- Postural orthostatic tachycardia syndrome (POTS)
Non-neurogenic causes:
- Cardiac impairment (e.g., myocardial infarction, aortic stenosis)
- Dehydration
- Adrenal insufficiency
- Vasodilation (e.g., fever)
- Medications like diuretics, alpha-blockers for BPH, antihypertensives, and calcium channel blockers
Diagnosing Orthostatic Hypotension
Diagnosis involves a tilt test or a tilt table test, monitoring blood pressure and heart rhythm from lying to standing positions, identifying significant changes that confirm orthostatic hypotension.
Managing Orthostatic Hypotension
Management aims at elevating standing blood pressure without adversely affecting supine blood pressure, focusing on reducing symptoms and improving daily activity tolerance. Strategies include:
- Abdominal compression and compression stockings
- Boluses of water for rapid symptom relief
- Bed elevation to mitigate morning symptoms
- Countermaneuvers like leg crossing and thigh muscle contraction
- Medication adjustments, considering fludrocortisone and midodrine
- Education on symptom triggers and management
- Exercise, favoring mild, recumbent activities
- Fluid and salt intake adjustments for optimal plasma volume