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SU23.1-2 | Adrenal Anatomy and Adrenal Disorders — SDL Guide (Part 2)

Principles of Management

Management rests on optimising the patient medically and then removing the source, usually by laparoscopic adrenalectomy, which is the standard approach for most benign functioning adenomas and is associated with less pain and faster recovery than open surgery; open or radical resection is reserved for large tumours or suspected/proven adrenocortical carcinoma. The single most important perioperative principle in surgery belongs to phaeochromocytoma: the patient must be prepared with ALPHA-blockade FIRST (classically phenoxybenzamine, or a selective alpha-1 blocker), continued for one to two weeks to control blood pressure and re-expand the contracted intravascular volume, and only after adequate alpha-blockade is a beta-blocker added if needed for tachycardia. Beta-blockade must NEVER be started first: blocking the vasodilatory beta-2 receptors while alpha-mediated vasoconstriction is still unopposed can precipitate a severe hypertensive crisis. The anaesthetist must also anticipate dramatic intra-operative blood pressure swings — surges when the tumour is handled and profound hypotension once its venous drainage is ligated — so the adrenal vein is secured early and fluid and vasoactive drugs are kept ready. For Cushing's syndrome and adrenocortical carcinoma, where the contralateral adrenal axis may be suppressed or the whole gland is being removed, the patient needs perioperative glucocorticoid (steroid) cover and a careful post-operative steroid replacement and taper to avoid an adrenal (Addisonian) crisis. For Conn's syndrome, a confirmed unilateral aldosterone-producing adenoma is cured by adrenalectomy, while bilateral hyperplasia is managed medically with an aldosterone antagonist such as spironolactone. Across all of these, the surgical decision to operate follows directly from the biochemical diagnosis, the localisation and the assessment of malignant potential.

Check Your Understanding

Bring the threads together by returning to the three patients in the hook and naming the hormone, the zone and the next step for each. The young woman with resistant hypertension and persistent hypokalaemia is the picture of Conn's syndrome: aldosterone from the zona glomerulosa, screened by the aldosterone:renin ratio, lateralised by adrenal vein sampling, and cured by removing a unilateral adenoma. The man with truncal obesity, striae, bruising and new diabetes has Cushing's syndrome: cortisol from the zona fasciculata, screened by the overnight dexamethasone suppression test, and requiring perioperative steroid cover when the source is removed. The man with paroxysmal headache, sweating and palpitations has a phaeochromocytoma: catecholamines from the medulla, screened by metanephrines, and prepared for surgery with alpha-blockade before beta-blockade. Use these to self-test the two competencies this module covers. First, can you describe the applied anatomy — the retroperitoneal position, the threefold arterial supply, and above all the asymmetric venous drainage that makes right adrenalectomy more hazardous? Second, can you state, for each functional disorder, the hormone in excess, the cardinal clinical features, the confirm-first screening test, and the key principle of management? The questions that follow check exactly these links.