What is a potential cause of sinus tachycardia that a nurse should investigate?

Sinus tachycardia is characterized by an increased heart rate originating from the sinoatrial node and is often a response to various physiological or psychological stimuli. Investigating anxiety as a potential cause is critical because it can significantly affect heart rate. When a person experiences anxiety, the body's sympathetic nervous system is activated, leading to the release of stress hormones such as adrenaline, which increases heart rate. This response can occur in situations of acute stress or anxiety disorders.

In contrast, while hyperkalemia, hypocalcemia, and hypoglycemia can influence heart rhythm and may contribute to arrhythmias, they are less likely to specifically cause sinus tachycardia on their own. For example, hyperkalemia is more commonly associated with bradycardia and other conduction abnormalities rather than increased heart rates. Hypocalcemia can lead to muscle twitching and may affect heart contractility, but it does not typically provoke sinus tachycardia directly. Hypoglycemia usually results in a range of symptoms including palpitations, but it more typically leads to autonomic responses like tremors and sweating rather than an isolated increase in heart rate like seen in sinus tachycardia caused by anxiety.

Thus, investigating anxiety is essential for understanding the patient's