A nurse is reviewing the vital signs of a client who has a prescription for imipramine. Which of the following findings requires follow-up by the nurse?

Imipramine is a tricyclic antidepressant (TCA) that carries significant cardiovascular risks due to its antagonism of alpha-1 adrenergic receptors. This pharmacological action frequently results in orthostatic hypotension and potential arrhythmias, necessitating diligent monitoring of hemodynamic status to prevent falls and other adverse cardiovascular events in psychiatric patients. A. A blood pressure of 88/64 mm Hg is significantly low and indicates hypotension. TCAs like imipramine are notorious for causing orthostatic hypotension and baseline low blood pressure. This finding requires immediate follow-up to prevent syncopal episodes and to determine if the dosage needs adjustment or if the client is experiencing toxicity. B. A pulse rate of 66/min is within the normal adult range of 60 to 100/min. While imipramine can sometimes cause tachycardia due to its anticholinergic properties, a normal heart rate does not indicate an adverse reaction and does not require the same level of urgent clinical follow-up as hypotension. C. A respiratory rate of 16/min is a normal physiological finding for an adult. Imipramine does not typically affect the respiratory drive at therapeutic levels. Therefore, this measurement indicates that the client’s ventilatory status is stable and does not warrant any specific nursing or medical intervention. D. A temperature of 36.7° C (98° F) is a normal afebrile reading. While certain psychiatric medications can interfere with thermoregulation or cause neuroleptic malignant syndrome, a normal body temperature indicates that the client is not currently experiencing a febrile adverse reaction or a systemic infection related to their therapy.