A patient is mowing his lawn on a hot Saturday afternoon.

He begins to notice chest pain.
What should his first action be?

Choice A rationale

Dehydration is not a primary complication directly associated with beta-blocker use. Beta-blockers, such as propranolol or metoprolol, primarily affect the cardiovascular system by blocking beta-adrenergic receptors, which decreases heart rate and blood pressure. Dehydration is typically caused by inadequate fluid intake or excessive fluid loss from conditions like vomiting, diarrhea, or diuresis.

Choice B rationale

Hyperkalemia is an elevated potassium level, which is a rare side effect of non-selective beta-blockers, but not a primary complication to monitor for in a patient taking a beta-blocker for hypertension. Hyperkalemia is more commonly associated with conditions like renal failure or the use of certain medications, such as ACE inhibitors or potassium-sparing diuretics.

Choice C rationale

Beta-blockers can mask the physiological signs of hypoglycemia in patients with diabetes, such as tremors, palpitations, and tachycardia. This occurs because the drugs block the sympathetic nervous system's compensatory response to low blood glucose, which normally involves the release of epinephrine. Consequently, a patient may not recognize a hypoglycemic event until it becomes severe.

Choice D rationale

Angina is a symptom of myocardial ischemia, and beta-blockers are often used to prevent it, not cause it. By reducing the heart rate and contractility, beta-blockers decrease myocardial oxygen demand. This effect helps to prevent chest pain associated with angina, making it a therapeutic benefit rather than a potential complication.

Choice A rationale

While taking a nitroglycerin tablet is a common treatment for angina, it should not be the first action. The immediate priority is to stop the activity causing the increased myocardial oxygen demand. Continuing to exert oneself can worsen myocardial ischemia and potentially lead to a more severe cardiac event, such as a myocardial infarction.

Choice B rationale

The primary action should be to stop the activity immediately and rest. Mowing the lawn is a strenuous activity that increases the heart's workload and oxygen demand. By stopping and resting, the patient decreases myocardial oxygen consumption, which can help alleviate the chest pain and prevent further myocardial ischemia.

Choice C rationale

While moving inside to cool off and get water may seem helpful, it is not the most critical first step. The immediate need is to reduce the cardiac workload, which is best achieved by ceasing the physical exertion. A patient should first sit or lie down to rest, as this action directly addresses the increased oxygen demand.

Choice D rationale

Calling 911 is crucial if the chest pain does not subside with rest or if it worsens. However, it is not the very first action to take. The initial step is always to stop the activity and rest, as this may be sufficient to resolve the symptoms. If the pain persists after resting, then it is appropriate to seek immediate emergency medical help.