What is the first-line vasopressor for cardiogenic shock?

From the Guidelines

Norepinephrine is the first-line vasopressor for cardiogenic shock, as it is associated with fewer arrhythmias and is likely the vasoactive drug of choice for most patients with cardiogenic shock. It should be initiated at 0.01-0.03 mcg/kg/min and titrated up to 0.5-1 mcg/kg/min as needed to maintain a mean arterial pressure (MAP) of at least 65 mmHg 1. Norepinephrine is preferred because it increases systemic vascular resistance and cardiac contractility while causing less tachycardia than other vasopressors, which is beneficial in cardiogenic shock where the heart is already compromised. The SOAP II trial reported a statistically significant higher risk of mortality with dopamine compared to norepinephrine in the pre-defined sub-group of patients with cardiogenic shock, supporting the use of norepinephrine as the first-line agent 1.

Some key points to consider when using norepinephrine in cardiogenic shock include:

• It works primarily through alpha-1 adrenergic receptor stimulation, causing vasoconstriction, with some beta-1 activity that provides inotropic support
• For patients with cardiogenic shock who remain hypotensive despite norepinephrine, adding dobutamine (2.5-20 mcg/kg/min) should be considered to improve cardiac output through its inotropic effects
• In cases where norepinephrine is unavailable, dopamine (5-15 mcg/kg/min) can be used as an alternative, though it carries a higher risk of tachyarrhythmias
• Central venous access is preferred for administration of these vasopressors, but peripheral administration can be used temporarily while central access is being established.

It's worth noting that the European Society of Cardiology guidelines from 2008 recommend vasopressors, such as norepinephrine, only when the combination of an inotropic agent and fluid challenge fails to restore SBP > 90 mmHg, with inadequate organ perfusion, despite an improvement in cardiac output 1. However, more recent evidence from the SOAP II trial supports the use of norepinephrine as the first-line agent in cardiogenic shock 1.

From the FDA Drug Label

Dopamine Hydrochloride in 5% Dextrose Injection, USP is indicated for the correction of hemodynamic imbalances present in shock due to myocardial infarction, trauma, endotoxic septicemia, open heart surgery, renal failure and chronic cardiac decompensation as in refractory congestive failure Patients most likely to respond to dopamine are those whose physiological parameters (such as urine flow, myocardial function and blood pressure) have not undergone extreme deterioration Low Cardiac Output: Dopamine's direct inotropic effect on the myocardium which increases cardiac output at low or moderate doses is related to a favorable prognosis Dopamine can be used as a first-line vasopressor for cardiogenic shock due to its ability to increase cardiac output and blood pressure.

• It is indicated for the correction of hemodynamic imbalances present in shock due to myocardial infarction and other conditions.
• Low to moderate doses of dopamine can be used to manage hypotension due to inadequate cardiac output. 2

From the Research

First-Line Vasopressor for Cardiogenic Shock

• The choice of first-line vasopressor for cardiogenic shock is a topic of ongoing debate, with various studies comparing the efficacy of different agents 3, 4, 5, 6, 7.
• Norepinephrine is commonly recommended as the first-line vasopressor agent for cardiogenic shock due to its minimal adverse effects and association with better outcomes in network meta-analyses 4, 5, 6.
• A study comparing dopamine and norepinephrine as first-line vasopressor therapy found no significant difference in 28-day mortality, but dopamine was associated with more arrhythmic events 3.
• Another study suggested that norepinephrine may be preferred over epinephrine in patients with cardiogenic shock, particularly after myocardial infarction 4, 6.
• The use of vasopressin may be advocated in patients with right ventricular failure and pulmonary hypertension, under advanced monitoring 6.
• A retrospective study comparing dopamine and norepinephrine as first-line vasopressors in cardiogenic shock found no significant difference in in-hospital mortality, but norepinephrine reduced the need for additional vasopressors 7.

Key Findings

• Norepinephrine is a reasonable first-line agent for restoring blood pressure in cardiogenic shock 4, 5, 6.
• Dobutamine is the first-line inotrope agent, while levosimendan can be used as a second-line agent or in patients previously treated with beta-blockers 4, 5.
• The choice of vasopressor and inotrope agents should be individualized and based on hemodynamic response 5.
• The use of vasopressors and inotropes in cardiogenic shock is limited by their side effects and the lack of solid evidence regarding their effectiveness in improving outcomes 4, 6.