8621 A Challenging Case of Preoperative Management of Pheochromocytoma Presenting With Recurrent Hypotension

Abstract Disclosure: N. Shripad: None. R. Osman: None. Introduction: Pheochromocytoma is a neuroendocrine tumor that clinically manifests due to the hypersecretion of catecholamines. Preoperative management typically involves alpha- and beta-adrenergic blockade. Patients commonly present with hypertension; however, in rare cases, patients may be hypotensive due to other comorbidities, posing a challenge to preoperative management. The following is a case of management of a pheochromocytoma with recurrent preoperative hypotension before the initiation of blood pressure-lowering agents. Case: A 47-year-old female presented to the hospital with dizziness and hypotension. The patient has a history of bilateral nephrectomy with left-sided adrenalectomy secondary to left-sided renal cell cancer and is hemodialysis-dependent. A right-sided pheochromocytoma was diagnosed a year ago on a follow-up CT scan done for monitoring renal cell cancer. The diagnosis was later confirmed with a DODATE scan and, eventually, a biopsy. Normetanephrine levels were between 581-735 pg/mL (0-88 pg/mL), with normal metanephrine levels. She denies having hyperadrenergic spells. She was started on metoprolol and doxazosin the year prior to presentation; however, she self-discontinued doxazosin after experiencing dizziness and palpitations on hemodialysis days. On admission, she was afebrile with a blood pressure of 103/66 mm Hg and a heart rate of 115 BPM. After an interdisciplinary decision was made for surgical resection, she was restarted on a lower dose of doxazosin (1 mg) and metoprolol was increased to the goal heart rate. Despite fewer hypotensive episodes on a reduced dose of doxazosin, the patient remained hypotensive on hemodialysis days. Salt tablets were started post-dialysis after clearance from nephrology, and an improvement in blood pressure was noted. She underwent a right adrenalectomy without receiving saline infusion before surgery due to concerns about volume overload. She was started on stress dose steroids due to her history of left adrenalectomy. She remained stable during and following surgery and did not require any vasopressor support. Discussion: Perioperative management of pheochromocytoma can be challenging in hypotensive patients and is poorly documented. Midodrine, an alpha-1 agonist that is typically used in dialysis-induced hypotension, is contraindicated in the setting of pheochromocytoma. We opted to manage our patient with a reduced dose of doxazosin and beta-blocker initially; however, with continued hypotensive episodes, the addition of salt tablets preoperatively on dialysis days helped to alleviate the hypotension. Although our patient did not require it, a preoperative overnight albumin infusion is a viable alternative to saline to prevent volume overload. Despite the limited literature, the patient was treated successfully through an interdisciplinary approach. Presentation: 6/3/2024