A male client recently admitted to hospital with sharp, substernal chest pain suddenly complains of palpitations. Nurse Ryan notes a rise in client’s arterial blood pressure and a heart rate of 144 beats/minute. On furr questioning, client admits to having used cocaine recently after previously denying use of drug. The nurse concludes that client is at high risk for which complication of cocaine use?

Correct Answer: A. Coronary artery spasm

Cocaine use may cause such cardiac complications as coronary artery spasm, myocardial infarction, dilated cardiomyopathy, acute heart failure, endocarditis, and sudden death. Cocaine blocks reuptake of norepinephrine, epinephrine, and dopamine, causing an excess of these neurotransmitters at postsynaptic receptor sites. Cocaine and its metabolites may cause arterial vasoconstriction hours after use. Epicardial coronary arteries are especially vulnerable to these effects, leading to a decreased myocardial oxygen supply.

• Option B: Consequently, the drug is more likely to cause tachyarrhythmias than bradyarrhythmias. Cocaine-induced central sympathetic stimulation and direct cardiac effects may lead to tachycardia, hypertension, and coronary or cerebral artery vasoconstriction leading to myocardial infarction and stroke.
• Option C: Although neurobehavioral deficits are common in neonates born to cocaine users, they are rare in adults. CNS reactions may be more excitatory than depressant. In its mild form, the patient may display anxiety, restlessness, and excitement. Full-body tonic-clonic seizures may result from moderate to severe CNS stimulation. These seizures are often followed by CNS depression, with death resulting from respiratory failure and/or asphyxiation if concomitant emesis is present.
• Option D: As craving for the drug increases, a person who’s addicted to cocaine typically experiences euphoria followed by depression, not panic disorder. Cardiovascular toxicity and agitation are best-treated first-line with benzodiazepines to decrease CNS sympathetic outflow. However, there is a risk of over-sedation and respiratory depression with escalating and numerous doses of benzodiazepines, which is often necessary. Non-dihydropyridine calcium channel blockers such as diltiazem and verapamil have shown the ability to reduce hypertension reliably, but not tachycardia.