Can adrenaline (epinephrine) be used as a first-line treatment for cardiogenic shock?

Epinephrine Should NOT Be Used as First-Line Treatment for Cardiogenic Shock

Epinephrine is explicitly not recommended as a first-line inotrope or vasopressor in cardiogenic shock and should be restricted to rescue therapy in cardiac arrest. 1

First-Line Treatment Algorithm for Cardiogenic Shock

Step 1: Initial Stabilization

• Fluid challenge first: Administer 250 mL over 10 minutes if clinically indicated 1
• Target systolic blood pressure (SBP) >90 mmHg with adequate organ perfusion 1

Step 2: Inotrope Selection (If SBP Remains <90 mmHg)

• Norepinephrine is the preferred first-line vasopressor for cardiogenic shock, as it causes fewer arrhythmias compared to alternatives 1, 2, 3
• Dobutamine (up to 20 μg/kg/min) is indicated when there is myocardial dysfunction with elevated cardiac filling pressures and low cardiac output 1, 2
• The combination of norepinephrine plus dobutamine is recommended as first-line treatment in patients with both low cardiac output and hypotension 2, 4

Step 3: Second-Line Options (If First-Line Fails)

• Add vasopressin (up to 0.03-0.06 U/min) if hypotension persists despite norepinephrine 1, 2
• Milrinone may be considered, especially in patients on beta-blockers, as its mechanism is independent of beta-adrenergic receptors 1
• Levosimendan can be used in select cases, though evidence is mixed regarding mortality benefit 1

Why Epinephrine Is NOT Recommended

Evidence Against Epinephrine in Cardiogenic Shock

The European Society of Cardiology explicitly states that epinephrine is not recommended as an inotrope or vasopressor in cardiogenic shock. 1 This recommendation is based on several critical concerns:

• Increased arrhythmias: Epinephrine causes significantly more arrhythmic events compared to norepinephrine 1, 5
• Lactic acidosis: Epinephrine infusion is associated with transient but concerning increases in lactate levels 5
• Impaired splanchnic perfusion: Studies show epinephrine increases the PCO2 gap (indicating inadequate gastric mucosa perfusion), while norepinephrine-dobutamine decreases it 5
• Higher heart rate: Epinephrine causes excessive tachycardia, which increases myocardial oxygen demand in an already compromised heart 5
• Risk of stress cardiomyopathy: Case reports document epinephrine-induced reverse Takotsubo cardiomyopathy requiring extracorporeal membrane oxygenation (ECMO) 6, 7

Direct Comparative Evidence

A prospective randomized trial comparing epinephrine versus norepinephrine-dobutamine in cardiogenic shock found that while both regimens increased cardiac output similarly, the norepinephrine-dobutamine combination was more reliable and safer. 5 Specifically:

• Epinephrine caused new arrhythmias in 3 patients 5
• Lactate increased with epinephrine but decreased with norepinephrine-dobutamine 5
• Diuresis increased significantly more with norepinephrine-dobutamine 5
• Plasma creatinine decreased in both groups, but renal perfusion appeared better preserved with norepinephrine-dobutamine 5

Critical Pitfalls to Avoid

• Never use epinephrine as first-line therapy in cardiogenic shock—it should only be used for cardiac arrest resuscitation 1
• Do not use vasopressors as a substitute for adequate fluid resuscitation in hypovolemic states 2, 4
• Avoid dopamine as first-line therapy: The SOAP II trial showed increased mortality in cardiogenic shock patients treated with dopamine versus norepinephrine 1
• Exercise extreme caution with all vasopressors in cardiogenic shock, as these patients typically have high systemic vascular resistance already 1
• Discontinue vasopressors as soon as possible to minimize adverse effects 1

When Mechanical Support Should Be Considered

• Intra-aortic balloon pump (IABP) should be considered if inotropes and vasopressors fail to restore adequate perfusion 1
• Left ventricular assist devices (LVADs) may be considered for potentially reversible causes as a bridge to recovery or definitive therapy 1
• ECMO may be necessary in refractory cases, particularly if cardiac arrest occurs 1, 6, 7