In conducting the initial assessment of a preoperative client, the nurse notes that the client's home medications include the monoamine oxidase (MAO) inhibitor phenelzine. Because of this client's medication history, which assessment finding is most important for the nurse to monitor?

Rationale: A. MAO inhibitors such as phenelzine can cause significant fluctuations in blood pressure, including hypertensive crisis when combined with certain foods or medications. Therefore, monitoring blood pressure is crucial to detect and prevent hypertensive emergencies. B. While monitoring urinary output is important for overall assessment, it is not specifically associated with the use of MAO inhibitors like phenelzine. C. Respiratory rate is not typically affected by MAO inhibitors like phenelzine and may not be the most relevant assessment finding in this scenario. D. Temperature monitoring is important for general assessment but is not specifically associated with the use of MAO inhibitors like phenelzine.