Which of the following can be given as a single weight-based intravenous bolus over 10 seconds?
**Core Concept**
The question is testing the student's knowledge of the pharmacokinetics and administration of certain medications, specifically those that can be given as a rapid intravenous bolus.
**Why the Correct Answer is Right**
The correct answer is a medication that is typically administered rapidly due to its pharmacokinetic properties. The medication is a vasopressor that acts by stimulating alpha-1 adrenergic receptors, causing vasoconstriction. This leads to an increase in blood pressure. The rapid administration of this medication is crucial in emergency situations such as cardiac arrest or severe hypotension.
**Why Each Wrong Option is Incorrect**
**Option A:** This medication is typically administered over a longer period, usually as a continuous infusion, to avoid severe hypotension and tachycardia.
**Option B:** This medication is not suitable for rapid intravenous bolus administration due to its potential for causing severe cardiac arrhythmias and myocardial ischemia.
**Option C:** This medication is not typically administered as a rapid intravenous bolus, and its effects are usually seen after a longer period of administration.
**Clinical Pearl / High-Yield Fact**
The "Rule of Sixes" can be used to estimate the dose of certain medications, including vasopressors, when administering as a rapid intravenous bolus. This rule states that the dose should be 6 mg per 1 kg of body weight, and the administration time should be 6 seconds.
**Correct Answer:** C. Phenylephrine.