What is the management plan for hypotension?

Management of Blood Pressure 90/60 mmHg

A blood pressure of 90/60 mmHg requires immediate assessment of the underlying cause and clinical context—treatment must be directed at the specific etiology (vasodilation, hypovolaemia, bradycardia, or low cardiac output) rather than reflexively administering fluids, as only approximately 50% of hypotensive patients are fluid-responsive. 1

Initial Assessment and Diagnostic Approach

The first critical step is determining which physiological derangement is causing the hypotension, as treatment differs fundamentally based on etiology 1:

• Assess for symptoms: Look for dizziness, lightheadedness, blurred vision, weakness, fatigue, nausea, palpitations, headache, syncope, dyspnea, chest pain, or neck/shoulder pain (coat hanger syndrome) 2, 3, 4
• Measure orthostatic vital signs: Check BP after 5 minutes lying/sitting, then at 1 and 3 minutes after standing—a drop of ≥20 mmHg systolic or ≥10 mmHg diastolic confirms orthostatic hypotension 5, 2, 3
• Evaluate heart rate response: Concomitant heart rate measurements assess baroreflex function and help differentiate neurogenic from nonneurogenic causes 2, 4

Perform Passive Leg Raise (PLR) Test Before Fluid Administration

Before giving any fluids, perform a PLR test to determine if hypovolaemia is contributing 1:

• An increase in cardiac output after PLR strongly predicts fluid responsiveness (positive likelihood ratio = 11; pooled specificity 92%) 1
• No increase in cardiac output after PLR indicates the patient will likely not respond to fluid (negative likelihood ratio = 0.13; pooled sensitivity 88%) 1
• This is critical because only 54% of postoperative hypotensive patients actually respond to fluid boluses 1

Cause-Directed Treatment Algorithm

If Hypovolaemia is Confirmed (Positive PLR Test)

• Administer intravascular fluids: Use crystalloid, colloid, or blood products as appropriate 1
• Look for clinical signs: Low jugular venous pressure, venoconstriction, poor tissue perfusion 6
• Avoid additional fluid boluses if cardiac dysfunction or volume overload signs (pulmonary edema) are present 1, 5

If Vasodilation is the Primary Problem

• Phenylephrine is best for hypotension with tachycardia (causes reflex bradycardia) 1
• Norepinephrine is indicated for acute hypotensive states including septicemia, myocardial infarction, and profound hypotension 7
• Epinephrine for septic shock: Start at 0.05 mcg/kg/min to 2 mcg/kg/min IV, titrated to achieve desired mean arterial pressure (MAP), adjusting every 10-15 minutes in increments of 0.05-0.2 mcg/kg/min 8

If Bradycardia is Present

• Atropine or glycopyrronium as first-line treatment 1
• Epinephrine or isoprenaline if refractory 1
• Consider pacing for profound bradycardia 1
• Look for "warm hypotension" with venodilatation and normal jugular venous pressure, often seen in inferior MI 6

If Low Cardiac Output is the Problem

• Dobutamine is recommended for myocardial dysfunction, starting at 2.5 μg/kg/min, increasing gradually at 5-10 min intervals up to 10 μg/kg/min 6, 1
• Dopamine 2.5-5.0 μg/kg/min IV if signs of renal hypoperfusion are present 6
• Assess for mechanical complications with echocardiography (mitral regurgitation, ventricular septal defect) 6

Blood Pressure Targets

Maintain mean arterial pressure (MAP) ≥60 mmHg in at-risk patients, as MAP <60-70 mmHg or systolic BP <90-100 mmHg is associated with acute kidney injury, myocardial injury, myocardial infarction, and death 6, 1:

• Increase MAP targets when venous or compartment pressures are elevated—add roughly the compartment pressure to your MAP target 6, 1
• In trauma patients without brain injury, a restricted volume replacement strategy with target systolic BP of 80-90 mmHg (MAP 50-60 mmHg) until major bleeding is controlled is appropriate 1
• In severe traumatic brain injury, maintain MAP ≥80 mmHg to ensure adequate cerebral perfusion 1

Medication Review and Non-Pharmacological Interventions

Review and Modify Medications

• Discontinue or switch culprit medications rather than simply reducing doses 9, 5
• Avoid beta-blockers and alpha-blockers in frail elderly patients unless specifically indicated 5
• Consider long-acting dihydropyridine calcium channel blockers or RAS inhibitors for elderly patients with both orthostatic hypotension and hypertension 5

Non-Pharmacological Measures (If Chronic Orthostatic Hypotension)

• Increase fluid intake to 2-3 liters daily and salt consumption to 6-9 grams daily (unless contraindicated by heart failure) 9, 5
• Teach physical counter-maneuvers: Leg crossing, squatting, stooping, and muscle tensing during symptomatic episodes 9, 5
• Use waist-high compression stockings (30-40 mmHg) and abdominal binders to reduce venous pooling 9
• Elevate the head of the bed (>10°) during sleep to reduce nocturnal diuresis 5

Pharmacological Treatment for Chronic Orthostatic Hypotension

• Midodrine 2.5-5 mg three times daily (last dose at least 3-4 hours before bedtime to prevent supine hypertension) is first-line with the strongest evidence base 9, 3, 4
• Droxidopa is FDA-approved for neurogenic orthostatic hypotension 5, 4
• Fludrocortisone 0.05-0.1 mg daily, titrated to 0.1-0.3 mg daily, but avoid in heart failure or significant cardiac dysfunction 9, 3

Monitoring and Common Pitfalls

Monitoring Recommendations

• Use continuous arterial pressure monitoring when possible—it reduces severity and duration of hypotension compared to intermittent monitoring 6, 1
• Monitor postoperative hypotension closely—it is often unrecognized and may be more important than intraoperative hypotension because it is prolonged and untreated 6, 1
• Titrate vasoactive agents to effect rather than using fixed doses, and avoid abrupt withdrawal of vasopressor infusions 1

Critical Pitfalls to Avoid

• Do not reflexively give fluids without assessing fluid responsiveness—approximately 50% of hypotensive patients are not hypovolemic 1
• Avoid aggressive fluid resuscitation in trauma without brain injury—it increases mortality 1
• Do not use permissive hypotension in traumatic brain injury—maintain MAP ≥80 mmHg 1
• Avoid treating only blood pressure numbers without addressing symptoms and quality of life 5
• Do not combine two RAS blockers (ACE inhibitor and ARB) 6

Special Considerations

• Elderly patients are at substantially higher risk due to impaired baroreceptor response and altered pharmacokinetics 9
• Exclude cardiogenic shock (systolic pressure <90 mmHg with central filling pressure >20 mmHg or cardiac index <1.8 L/min/m²) and other causes like vasovagal reactions, electrolyte disturbances, or arrhythmias 6
• Consider endocrine causes in chronic hypotension: adrenal failure, hypoaldosteronism, pheochromocytoma, or diabetic dysautonomia 10