What are the signs and symptoms of hypotension?

Signs and Symptoms of Hypotension

Hypotension is defined as a systolic blood pressure less than 90 mmHg or a mean arterial pressure less than 65 mmHg in resting conditions. 1, 2 Recognition of hypotension's clinical manifestations is crucial for proper diagnosis and management.

Common Signs and Symptoms

Neurological Manifestations

• Dizziness and lightheadedness, particularly when changing positions 1, 2
• Syncope or near-syncope episodes 1
• Altered mental status or confusion in severe cases 1
• Headache 2
• Visual disturbances including blurred vision 2

Cardiovascular Manifestations

• Tachycardia (compensatory response) 3
• Weak, thready pulse 1
• Pale, cool skin in severe hypoperfusion 1
• Delayed capillary refill 1

Gastrointestinal Manifestations

• Nausea and vomiting 3, 2
• Abdominal discomfort 3

Musculoskeletal Manifestations

• Muscle cramps 3
• Generalized weakness 1
• Fatigue 2, 4

Respiratory Manifestations

• Sighing or yawning (often seen in intradialytic hypotension) 3
• Dyspnea 3

Special Forms of Hypotension

Orthostatic Hypotension

• Defined as a decrease in systolic BP ≥20 mmHg or diastolic BP ≥10 mmHg within 3 minutes of standing 3, 5
• May cause more pronounced symptoms when changing positions 3
• Often associated with autonomic dysfunction 3, 6
• May be asymptomatic in some patients despite significant BP drops 3

Intradialytic Hypotension

• Occurs in approximately 25% of hemodialysis sessions 3
• Presents with abdominal discomfort, yawning, sighing, nausea, vomiting, muscle cramps, restlessness, dizziness, and anxiety 3
• Can lead to cardiac arrhythmias and predispose to coronary/cerebral ischemic events 3

Severity Assessment

Critical Thresholds

• Systolic BP <80 mmHg is considered a critical threshold requiring immediate intervention 3, 1
• In children, age-specific thresholds apply: 70 mmHg for 1 month to 1 year, (70 mmHg plus twice the age) for 1-10 years, and 90 mmHg for 11-17 years 1, 5

Signs of End-Organ Hypoperfusion

• Decreased urine output 1
• Worsening renal function 3
• Cardiac ischemia manifestations 3
• Neurological deficits 1

Diagnostic Approach

Initial Assessment

• Confirm blood pressure readings in both supine and standing positions 3, 5
• Correlate symptoms with documented hypotensive episodes 3
• Consider ambulatory blood pressure monitoring (ABPM) if office measurements don't correlate with symptoms 3, 5

Clinical Pearls

• Hypotension may be asymptomatic in some patients despite low readings 3, 4
• The presence of symptoms is more clinically significant than absolute BP values in many cases 2
• Patients with chronic hypertension may experience hypotension symptoms at "normal" BP levels 2
• Duration of hypotension episodes correlates with risk of adverse outcomes 2

Common Pitfalls

• Failing to distinguish between asymptomatic low BP and symptomatic hypotension requiring intervention 2
• Not recognizing that hypotension thresholds may be higher in patients with chronic hypertension 2
• Overlooking orthostatic hypotension, which should be assessed when suggestive symptoms arise 2
• Ignoring the duration of hypotension episodes, which is a critical factor in determining risk 2

By recognizing these signs and symptoms promptly, clinicians can better identify hypotension and initiate appropriate management strategies to prevent complications and improve patient outcomes.