Which of the following drug is used in CPR?
**Core Concept**
The question is testing knowledge of pharmacological interventions in cardiopulmonary resuscitation (CPR), specifically the use of vasopressors to maintain blood pressure during cardiac arrest. Vasopressors are medications that constrict blood vessels, increasing peripheral resistance and blood pressure.
**Why the Correct Answer is Right**
Epinephrine (adrenaline) is the preferred vasopressor in CPR due to its potent vasoconstrictive effects and ability to stimulate the heart. It works by stimulating alpha-adrenergic receptors on blood vessels, causing vasoconstriction and increasing blood pressure. Additionally, epinephrine has a direct stimulatory effect on the heart, increasing cardiac contractility and heart rate. This helps to improve circulation and maintain vital organ perfusion during cardiac arrest.
**Why Each Wrong Option is Incorrect**
**Option A:** Vasopressin is another vasopressor used in CPR, but it is not the preferred agent. Vasopressin has a shorter duration of action compared to epinephrine and is often used in combination with epinephrine.
**Option B:** Norepinephrine is a potent vasopressor, but it is not typically used in CPR due to its potential to cause vasoconstriction and decreased cardiac output.
**Option C:** Dopamine is a vasopressor with both alpha and beta-adrenergic effects, but it is not the preferred agent in CPR due to its potential to cause tachycardia and decreased cardiac output.
**Clinical Pearl / High-Yield Fact**
During CPR, the goal is to maintain a mean arterial pressure of at least 60-70 mmHg to ensure adequate organ perfusion. Vasopressors like epinephrine are used to achieve this goal, but the specific choice of vasopressor may depend on the underlying cause of cardiac arrest and the presence of any contraindications.
**Correct Answer:** C. Epinephrine.