How is vasoplegia best managed?

Management of Vasoplegia

Vasoplegia should be treated first-line with α1-adrenergic agonist vasopressors (norepinephrine or phenylephrine), and when refractory to catecholamines, add vasopressin, methylene blue, or terlipressin as second-line agents, either alone or in combination. 1

Initial Assessment and Hemodynamic Targets

• Maintain mean arterial pressure (MAP) between 50-80 mmHg during the acute phase, ensuring adequate depth of anesthesia and sufficient cardiac output before escalating vasopressors 1
• Do not force MAP above 80 mmHg with vasopressors, as this is associated with worse outcomes 1
• Monitor for adequate tissue perfusion using mixed venous oxygen saturation (SvO2 >75%), oxygen extraction ratio, lactate levels, and regional cerebral oxygen saturation 1
• Ensure euvolemia before escalating vasopressor therapy—titrate fluid resuscitation based on hemodynamic response parameters 1

First-Line Vasopressor Therapy

• Norepinephrine is the first-line vasopressor for vasoplegia due to fewer side effects and potentially lower mortality compared to dopamine 2, 1
• Norepinephrine increases systemic vascular resistance through α1-adrenergic receptor stimulation while maintaining cardiac output 1
• Epinephrine can be used when both vasopressor and inotropic support are needed, particularly if myocardial dysfunction is present 1
• Avoid dopamine as first-line therapy—it is associated with increased arrhythmic events and inconsistent hemodynamic improvement in vasoplegia 1
• Phenylephrine may be considered as an alternative α1-agonist, though evidence is less robust than for norepinephrine 1

Second-Line Therapy for Refractory Vasoplegia

When vasoplegia persists despite adequate doses of catecholamine vasopressors:

• Add vasopressin (0.03-0.06 U/min) for its norepinephrine-sparing effects 1, 3

  • Vasopressin increases afterload without pulmonary vasoconstriction and may benefit right heart function 1
  • Use caution as primary agent in post-cardiac surgery vasoplegia due to reports of dysrhythmia and myocardial infarction 1
  • Monitor for additive effects on blood pressure when combined with catecholamines 3

• Consider methylene blue (2 mg/kg IV over 20 minutes) for catecholamine-refractory vasoplegia 1, 4

  • Methylene blue inhibits guanylate cyclase and reduces nitric oxide-mediated vasodilation 4
  • Produces clinically relevant increases in systemic vascular resistance within 1 hour in approximately 93% of patients 4
  • No significant adverse effects observed in clinical studies 4

• Terlipressin is an alternative vasopressin analog for refractory cases 1

  • Can be used alone or in combination with α1-agonists 1

Third-Line and Rescue Therapies

• Hydroxocobalamin may be considered as an alternative agent, though evidence is limited (Class IIb recommendation) 1
• Angiotensin II substantially increases systemic vascular resistance without altering cardiac output in vasoplegic shock 1
• Corticosteroids (hydrocortisone) may have synergistic effects with vasopressin, particularly in septic shock-related vasoplegia 1

Context-Specific Considerations

Post-Cardiac Surgery Vasoplegia

• α1-adrenergic agonists are recommended as first-line treatment 1
• Methylene blue or vasopressin may improve survival when used early 1
• Avoid vasopressin as sole primary agent due to cardiac complications 1

Vasoplegia with Myocardial Dysfunction

• Norepinephrine is preferred over epinephrine alone, as epinephrine monotherapy is associated with higher mortality 1
• Consider adding inotropic support (dobutamine, milrinone, or levosimendan) if cardiac output remains low despite adequate preload 1, 2
• High-dose insulin (1 U/kg bolus, then 1 U/kg/hr infusion) with dextrose should be considered for documented myocardial dysfunction 1

Calcium Channel Blocker Toxicity-Related Vasoplegia

• Norepinephrine is recommended to increase blood pressure in vasoplegic shock 1
• Epinephrine is recommended to increase contractility and heart rate 1
• High infusion rates of vasopressors may be required 1

Critical Pitfalls to Avoid

• Do not use excessive vasopressor doses to achieve MAP >80 mmHg—this worsens outcomes without improving organ perfusion 1
• Avoid dopamine for vasoplegia—it increases arrhythmias and mortality compared to norepinephrine 1
• Do not use vasopressin alone as primary therapy in post-cardiac surgery patients due to increased risk of dysrhythmia and myocardial infarction 1
• Ensure adequate volume resuscitation before escalating vasopressors—vasoplegia management assumes euvolemia 1
• At high doses, vasopressin markedly impairs splanchnic circulation; use lowest effective dose 1
• Monitor for Harlequin syndrome in ECMO patients—differential oxygenation may complicate vasoplegia management 1

Monitoring During Treatment

• Continuously assess hemodynamic parameters including cardiac output, systemic vascular resistance, and MAP 1
• Monitor tissue perfusion markers: SvO2, lactate, urine output, and regional oxygen saturation 1
• Adjust vasopressor doses based on hemodynamic response rather than fixed targets 3
• Echocardiography should be used to assess cardiac function and guide therapy selection 1