A 29-year-old man comes to the emergency department complaining of palpitations, sweating, and severe headache. His symptoms resolve spontaneously by the time he is evaluated. He has had at least 2 similar episodes during the past 2 months. The patient's family history is unremarkable. He does not use tobacco, alcohol, or illicit drugs. His primary care provider saw him after the first episode and prescribed an anxiolytic medication. However, the patient felt drowsy at his job and stopped the medication. Physical examination shows a thin man who appears anxious and diaphoretic. The thyroid is normal to palpation without any obvious nodules. His temperature is 36.7 C (98 F), blood pressure is 126/84 mm Hg, pulse is 86/min, and respirations are 16/min. During his prior emergency department visit for an identical episode, his blood pressure was 150/100 mm Hg and pulse was 120/min. The laboratory results at that time showed normal thyroid function tests. The patient is placed on appropriate preoperative medications and is taken for surgical removal of the tumor. During the procedure, he rapidly becomes hypotensive. His blood pressure falls from 110/89 mm Hg to 80/50 mm Hg. Which of the following is the most appropriate therapy for this patient's hypotension?

Question

A 29-year-old man comes to the emergency department complaining of palpitations, sweating, and severe headache.  His symptoms resolve spontaneously by the time he is evaluated.  He has had at least 2 similar episodes during the past 2 months.  The patient's family history is unremarkable.  He does not use tobacco, alcohol, or illicit drugs.  His primary care provider saw him after the first episode and prescribed an anxiolytic medication.  However, the patient felt drowsy at his job and stopped the medication.  Physical examination shows a thin man who appears anxious and diaphoretic.  The thyroid is normal to palpation without any obvious nodules.  His temperature is 36.7 C (98 F), blood pressure is 126/84 mm Hg, pulse is 86/min, and respirations are 16/min.  During his prior emergency department visit for an identical episode, his blood pressure was 150/100 mm Hg and pulse was 120/min.  The laboratory results at that time showed normal thyroid function tests. The patient is placed on appropriate preoperative medications and is taken for surgical removal of the tumor.  During the procedure, he rapidly becomes hypotensive.  His blood pressure falls from 110/89 mm Hg to 80/50 mm Hg.  Which of the following is the most appropriate therapy for this patient's hypotension?

Quizplus · Accepted Answer

Explanation: 11ec2b69_bed7_8b9d_8f63_1bf19168968f_MD0005_00 Even with adequate preoperative alpha blockade and adequate fluid replenishment, some patients with pheochromocytoma have intraoperative and postoperative complications. Hypotension is an important intraoperative complication due to decreased circulatory catecholamine levels following tumor removal. In addition, persistent preoperative alpha blockade results in decreased vascular tone. Intra- and postoperative hypotension usually responds well to normal saline bolus. Pressors may be required in patients who do not respond to intravenous fluids. Other complications include hypertensive crisis, hypoglycemia, and cardiac tachyarrhythmias. (Choices B and C) Dopamine and dobutamine are less effective in those with pheochromocytoma and intraoperative hypotension as the majority of these patients are on preoperative long-acting alpha blockade. As a result, the vascular response to vasoconstrictors is reduced. (Choice D) Studies have not shown that colloids are superior to crystalloid solution in the management of acute hypotension. In addition, colloids are more expensive than normal saline. (Choice E) Intravenous infusion of phentolamine or sodium nitroprusside is preferred for managing intraoperative severe hypertension. Educational objective: Intraoperative hypotension in patients with pheochromocytoma usually responds to an intravenous bolus of normal saline. Intravenous bolus of phentolamine is used for acute severe hypertension (not hypotension) during surgery for pheochromocytoma. References: Phaeochromocytoma. (http://www.ncbi.nlm.nih.gov/pubmed/16112304) Laparoscopic adrenalectomy for pheochromocytoma: a literature review. (http://www.ncbi.nlm.nih.gov/pubmed/12487269)

A 29-Year-Old Man Comes to the Emergency Department Complaining of Palpitations