What are the treatment options for a patient with hypotension?

Treatment of Hypotension

The treatment of hypotension depends critically on the underlying cause and clinical context: assess fluid responsiveness with passive leg raise testing before giving fluids, use norepinephrine for vasodilatory hypotension, and reserve fluid boluses only for hypovolemic patients who demonstrate fluid responsiveness. 1

Initial Assessment and Diagnostic Approach

Before initiating any treatment, determine the mechanism of hypotension through structured evaluation:

• Perform a passive leg raise (PLR) test to assess fluid responsiveness, which has 92% specificity and a positive likelihood ratio of 11 for predicting fluid response 1
• An increase in cardiac output after PLR indicates the patient will respond to fluids (88% sensitivity), while no increase means vasopressors or inotropes are needed instead (negative likelihood ratio 0.13) 1
• Measure blood pressure after 5 minutes of sitting/lying, then at 1 and 3 minutes after standing to identify orthostatic hypotension 2, 1
• Verify BP readings and assess whether symptoms (dizziness, fatigue) correspond temporally to low BP values, particularly when standing or in upright position 3

Critical pitfall: Approximately 50% of hypotensive patients are not hypovolemic and require vasopressors or inotropes instead of fluids—do not reflexively administer fluids without assessing fluid responsiveness 1

Cause-Directed Treatment Algorithm

For Vasodilatory Hypotension

• Administer norepinephrine as first-line vasopressor for vasodilation-mediated hypotension 1
• Use phenylephrine when hypotension occurs with tachycardia, as it causes reflex bradycardia 1
• Titrate vasoactive agents to effect rather than using fixed doses, and reduce gradually rather than abruptly withdrawing 1

For Hypovolemic Hypotension

• Administer intravascular fluids only if PLR test is positive 1
• Give initial fluid bolus of 250-500 mL in adults 1
• In pediatric patients, administer 10-20 mL/kg normal saline (maximum 1,000 mL) 1
• Avoid additional fluid boluses in patients with cardiac dysfunction or signs of volume overload (pulmonary edema) 1

For Anesthesia-Related Hypotension

• Ephedrine sulfate 5-10 mg IV bolus as needed, not exceeding 50 mg total, is FDA-approved for clinically important hypotension occurring during anesthesia 4
• Be aware that repeated administration may cause tachyphylaxis 4

Blood Pressure Targets by Clinical Context

General Surgical Patients

• Maintain mean arterial pressure (MAP) ≥60 mmHg in at-risk surgical patients 1
• MAP <60-70 mmHg or systolic BP <90-100 mmHg is associated with acute kidney injury, myocardial injury, and death 1
• Increase MAP targets when venous or compartment pressures are elevated—add roughly the compartment pressure to your MAP target 1

Trauma Without Brain Injury

• Use restricted volume replacement targeting systolic BP 80-90 mmHg (MAP 50-60 mmHg) until major bleeding is controlled 1

Severe Traumatic Brain Injury

• Maintain MAP ≥80 mmHg to ensure adequate cerebral perfusion 1

Acute Heart Failure with Hypoperfusion

• Avoid diuretics until adequate perfusion is attained 1
• Use beta-blockers cautiously if the patient is hypotensive 1
• In patients with severely symptomatic fluid overload without systemic hypotension, vasodilators (IV nitroglycerin, nitroprusside, or nesiritide) can be added to diuretics 1

Management of Orthostatic Hypotension

When hypotension is primarily postural, a stepwise approach is warranted:

Step 1: Identify and Remove Causative Factors

• Discontinue or switch medications that worsen orthostatic hypotension rather than simply reducing doses 2
• Drug-induced autonomic failure is the most frequent cause, with diuretics and vasodilators being the most important culprits 2
• Discontinue alpha-1 blockers (doxazosin, prazosin, terazosin, tamsulosin), centrally acting agents (clonidine, methyldopa), and vasodilators (hydralazine, minoxidil) 2
• Avoid alcohol, which causes both autonomic neuropathy and central volume depletion 2

Step 2: Non-Pharmacological Interventions

• Increase fluid intake to 2-3 liters daily and salt intake to 6-9 grams daily, unless contraindicated by heart failure 2
• Teach physical counter-maneuvers: leg crossing, squatting, stooping, and muscle tensing during symptomatic episodes (particularly effective in patients under 60 years with prodromal symptoms) 2
• Use waist-high compression stockings (30-40 mmHg) and abdominal binders to reduce venous pooling 2
• Elevate head of bed by 10 degrees during sleep to prevent nocturnal polyuria and ameliorate nocturnal hypertension 2
• Eat smaller, more frequent meals to reduce postprandial hypotension 2
• Encourage physical activity and exercise to avoid deconditioning 2

Step 3: Pharmacological Treatment for Persistent Symptoms

First-line pharmacological therapy:

• Midodrine 2.5-5 mg three times daily, with the last dose at least 3-4 hours before bedtime (not after 6 PM) to prevent supine hypertension 2
• Midodrine has the strongest evidence base among pressor agents, with three randomized placebo-controlled trials demonstrating efficacy 2
• Can increase standing systolic BP by 15-30 mmHg for 2-3 hours 2
• Titrate individually up to 10 mg two to four times daily 2

Alternative or adjunctive first-line options:

• Fludrocortisone 0.05-0.1 mg once daily, titrate to 0.1-0.3 mg daily 2

• Acts through sodium retention and vessel wall effects 2

• Monitor for supine hypertension, hypokalemia, congestive heart failure, and peripheral edema 2

• Contraindicated in patients with active heart failure or significant cardiac dysfunction 2

• Droxidopa is FDA-approved and particularly effective for neurogenic orthostatic hypotension in Parkinson's disease, pure autonomic failure, and multiple system atrophy 2

For refractory cases:

• Pyridostigmine 60 mg orally three times daily (maximum 600 mg daily) for elderly patients refractory to first-line treatments, particularly those with concurrent supine hypertension 2
• Works by enhancing ganglionic sympathetic transmission without worsening supine BP 2
• Common side effects include nausea, vomiting, abdominal cramping, sweating, salivation, and urinary incontinence 2

Combination therapy:

• For non-responders to monotherapy, consider combining midodrine and fludrocortisone, as they work through complementary mechanisms 2

Special Considerations for Heart Failure with Reduced Ejection Fraction (HFrEF)

Critical Thresholds

• Systolic BP <80 mmHg or hypotension causing major symptoms warrants careful attention and may necessitate re-evaluation of guideline-directed medical therapy (GDMT) 3
• Hypotension associated with minor symptoms is not a reason to withhold or reduce HF GDMT 3
• Focus assessment on symptoms and organ perfusion rather than BP metrics alone, as low BP does not always correlate with impaired perfusion 3

Treatment-Naïve Patients with HFrEF and Low BP

If BP normalizes after discontinuing non-HF hypotensive treatments, commence GDMT promptly 3. For persistent low BP in asymptomatic or mildly symptomatic patients with adequate perfusion:

• Start SGLT2 inhibitors and mineralocorticoid receptor antagonists (MRAs) first, as these have the least effect on BP but rapid beneficial effect 3
• Subsequently, consider low-dose beta-blocker (if HR >70 bpm) or low-dose sacubitril/valsartan (50 mg twice daily or very low 25 mg twice daily), then gradually up-titrate 3
• Selective β₁ receptor blockers may be preferred due to lesser BP-lowering effect than non-selective beta-blockers 3
• If beta-blockers are not well tolerated hemodynamically, ivabradine may be considered 3

Monitoring Recommendations

• Use continuous intraoperative arterial pressure monitoring to reduce severity and duration of hypotension compared to intermittent monitoring 1
• Monitor fluid intake/output, vital signs, daily weights, and clinical signs of perfusion and congestion 1
• Measure daily serum electrolytes, urea nitrogen, and creatinine during IV diuretic use or active medication titration 1
• Measure both supine and standing BP at each visit when treating orthostatic hypotension 2
• Monitor for supine hypertension development, which can cause end-organ damage 2
• The therapeutic goal is minimizing postural symptoms and improving functional capacity, NOT restoring normotension 2

Critical Pitfalls to Avoid

• Do not reflexively administer fluids without PLR testing—50% of hypotensive patients need vasopressors, not fluids 1
• Do not simply reduce doses of offending medications; switch to alternative therapy instead 2
• Do not administer midodrine after 6 PM due to risk of supine hypertension during sleep 2
• Do not use fludrocortisone in patients with heart failure or supine hypertension 2
• Do not combine multiple vasodilating agents without careful monitoring 2
• Do not overlook volume depletion as a contributing factor 2
• Postoperative hypotension is often unrecognized and may be more important than intraoperative hypotension because it is prolonged and untreated 1