A client admitted with thyrotoxicosis is reporting a "pounding heart in the chest." Which assessment finding warrants immediate intervention by the nurse?

A. Anxiety is a common symptom in patients with thyrotoxicosis due to increased metabolic activity and overstimulation of the nervous system. While anxiety can be distressing, it is not typically life- threatening and does not usually require immediate intervention. B. Hyperglycemia (high blood glucose levels) can occur in patients with thyrotoxicosis due to increased metabolic rate and potential effects on insulin sensitivity. It requires monitoring and management but typically does not demand immediate intervention unless it is severe and causing other complications. C. Fever can be a sign of thyroid storm, a severe form of thyrotoxicosis that can be life-threatening. Elevated body temperature in the context of thyrotoxicosis requires prompt assessment as it may indicate an underlying severe condition or complications. D. Dyspnea is a critical symptom that warrants immediate intervention. In the context of thyrotoxicosis, it may indicate a severe complication such as heart failure, thyroid storm, or respiratory distress. Given that dyspnea can lead to compromised oxygenation and potentially life-threatening situations, it is the most urgent symptom to address.