From the Guidelines
Epinephrine should be administered in pulseless ventricular tachycardia (VT) to improve coronary and cerebral perfusion during resuscitation efforts, with a recommended dose of 1 mg IV/IO every 3-5 minutes throughout the resuscitation, as supported by the most recent guidelines 1. The primary goal of administering epinephrine in pulseless VT is to increase the likelihood of successful defibrillation by improving coronary perfusion pressure, which is crucial for the heart muscle to respond to defibrillation attempts.
- Key points to consider when administering epinephrine in pulseless VT include:
- Establishing IV/IO access quickly to ensure timely administration of epinephrine
- Following each dose with a 20 mL fluid flush and elevating the extremity if peripheral access is used
- Understanding that epinephrine works through its alpha-adrenergic effects to cause peripheral vasoconstriction, increasing aortic diastolic pressure and improving coronary perfusion pressure
- Recognizing that while epinephrine's beta-adrenergic effects can increase myocardial oxygen demand and potentially worsen ischemia, the alpha effects are considered beneficial during cardiac arrest
- It is essential to note that epinephrine should be given alongside defibrillation attempts, which remain the primary intervention for pulseless VT, and should never delay defibrillation, as it offers the best chance for successful resuscitation in this shockable rhythm 1.
- The most recent guidelines suggest that for shockable rhythms, such as pulseless VT, epinephrine should be administered after initial defibrillation attempts are unsuccessful during CPR 1, but the 2024 update from the American Heart Association supports the use of epinephrine as part of the ACLS algorithm for pulseless VT, with the dose of 1 mg IV/IO every 3-5 minutes 1.
From the Research
Rationale for Administering EPi in Pulseless VTach
- The administration of epinephrine (EPi) in pulseless ventricular tachycardia (VTach) is a recommended practice in advanced cardiac life support (ACLS) guidelines 2, 3.
- EPi is used to facilitate defibrillation in patients with pulseless VTach or ventricular fibrillation, and it is also an alternative to vasopressin 3.
- The use of EPi in cardiac arrest management is supported by evidence, which suggests that it may improve rates of return of spontaneous circulation (ROSC), although it is not associated with improved survival with a favorable neurologic outcome 2.
- In the context of refractory VTach or ventricular fibrillation, the combination of EPi with other interventions such as esmolol administration, vector change defibrillation, and dose-capped EPi may improve clinical outcomes, including sustained ROSC and survival to hospital arrival 4.
Mechanism of Action and Clinical Considerations
- EPi works by stimulating the heart and increasing the likelihood of successful defibrillation 3.
- The optimal dose and timing of EPi administration in pulseless VTach are important considerations, with guidelines recommending 1 mg of EPi if initial CPR and defibrillation are unsuccessful 2.
- The use of EPi in combination with other antiarrhythmic drugs, such as amiodarone, may also be effective in facilitating defibrillation and improving clinical outcomes 5, 6.
- However, the evidence for the use of antiarrhythmic drugs in cardiac arrest is uncertain, and the choice of drug and dose should be individualized based on patient factors and clinical circumstances 5, 6.