Current perioperative management of pheochromocytomas

Abstract

Neuroendocrine tumors which have the potential to secrete catecholamines are either associated with sympathetic adrenal (pheochromocytoma) or nonadrenal (paraganglioma) tissue. Surgical removal of these tumors is always indicated to cure and prevent cardiovascular and other organ system complications associated with catecholamine excess. Some of these tumors have malignant potential as well. The diagnosis, localization and anatomical delineation of these tumors involve measurement of catecholamines and their metabolic end products in plasma and urine, 123I-metaiodobenzylguanidine scintigraphy, computed tomography, and/or magnetic resonance imaging. Before surgical removal of the tumors, the optimization of blood pressure, as well as intravascular volume, is an important measure to avoid and suppress perioperative adverse hemodynamic events. Preoperative preparation includes the use of alpha-adrenergic antagonists, beta-adrenergic antagonists with or without other antihypertensive agents, fluid therapy as well as insulin therapy for hyperglycemia if required. Due attention should be given to type and dose of alpha-receptor antagonists to be used and the duration of this therapy to achieve an optimal level of preoperative “alpha-blockade.” Despite this preoperative preparation, many patients will have hypertensive crises intraoperatively which need to be promptly and carefully managed by the anesthesia team which requires intensive and advanced monitoring techniques. The most common complication after tumor removal is hypotension which may require fluid therapy and vasopressor support for a few hours. With advancement in surgical and anesthetic techniques, the incidence of severe morbidity and mortality associated with the surgery is low in high volume centers.

Undiagnosed pheochromocytoma presenting as a pancreatic tumor: A case report

“…In patients who receive alpha-blockers preoperatively, intraoperative blood pressure elevations should be managed with other intravenous antihypertensive drugs, such as sodium nitro-prusside, as used in our hospital. Perioperative mortality is low in patients who undergo planned removal of pheochromocytoma, due to preoperative use of alpha-blockers to prevent hypertensive crises and intravenous fluids to reduce potential hypotension [15].…”

Preoperative selective vs non-selective α-blockade in PPGL patients undergoing adrenalectomy

“…Some studies are highly specialized and discuss laparoscopic adrenalectomy to provide a technique-specific conclusion ( 17 , 18 ). However, open adrenalectomy, which is more widely used and recognized in China and many other countries, has not been specifically researched ( 19 ). Also, some unspecialized studies have considered only general patient and tumor conditions and produced only partial statistical results leading to biased conclusions ( 20 ).…”

Thrombotic Tendencies in Excess Catecholamine States

“…Removal of tumours producing excess catecholamines play a crucial role in alleviating symptoms associated with hypertension and thus thrombus formation. Due exaggerated fall in blood pressure after surgical removal of these tumours, adequate vascular volume replacement with oral fluids and salt is recommended [38].…”