Final answer:
The vital signs, especially blood pressure, of a pre-op client undergoing adrenalectomy for a pheochromocytoma should be the most closely monitored parameter due to the risk of episodic hypertension associated with catecholamine release by the tumor.
Step-by-step explanation:
A preoperative client scheduled for adrenalectomy to remove a pheochromocytoma should have their vital signs closely monitored. Pheochromocytomas can cause episodic hypertension due to the secretion of catecholamines (such as norepinephrine, also called noradrenaline), which can greatly increase blood pressure. During the preoperative period, it's critical to ensure that the patient's blood pressure is controlled to prevent complications such as stroke, heart attack, or hypertensive crisis. Therefore, the answer to the question is A. Vitals.
The sympathetic nervous system affects kidney function and blood flow. Increased sympathetic activity, which includes the release of norepinephrine and aldosterone, can lead to vasoconstriction and a subsequent decrease in glomerular flow and filtration rate. This interplay is crucial for regulating blood pressure, which is closely related to the action of pheochromocytomas on the cardiovascular system.
Aldosterone, a hormone released by the adrenal cortex, causes the kidneys to reabsorb sodium and water, ultimately increasing blood volume and pressure. In the case of a pheochromocytoma, careful management of fluid and electrolyte balance is necessary, but the priority is monitoring vital signs, particularly blood pressure, due to the potential for severe fluctuations.