dromlakhani Manage perioperative volume for pheochromocytoma and paraganglioma surgery
STEP 1 — Gather Information
Confirm diagnosis of functional PPGL (elevated fractionated metanephrines/catecholamines), record current α‑blocker type and dose, baseline seated and standing blood pressure, heart rate, signs of orthostatic hypotension, and volume status (e.g., BUN/creatinine, edema). Assess renal function and any contraindications to saline infusion.
STEP 2 — Rule In / Rule Out
Rule in functional PPGL requiring perioperative volume expansion if biochemical testing shows catecholamine overproduction (↑ metanephrines/normetanephrine ≥3× ULN) and the patient is scheduled for tumor resection. Rule out if biochemical studies are normal (non‑catecholamine‑producing PPGL) or if the patient has uncontrolled heart failure or severe renal insufficiency that would contravene saline loading.
STEP 3 — Classify or Stratify
Classify volume status based on BP response to α‑blocker: if systolic BP <130/80 mmHg seated and orthostatic systolic drop ≥20 mmHg or symptomatic hypotension, consider intravascular volume depletion; if BP remains elevated or orthostatic change minimal, assume adequate or excess volume. Stratify salt intake target: aim for euvolemia by adjusting oral NaCl to maintain BP goal and relieve orthostatic signs.
STEP 4 — Decide
On day 3 of α‑blocker therapy, start a normal salt diet (≈9 g NaCl/day). Adjust daily NaCl intake upward or downward according to seated BP <130/80 mmHg and improvement of orthostatic hypotension, avoiding frank hypertension. From the evening before surgery until the procedure, administer 1–2 L isotonic saline intravenously (e.g., 0.9% NaCl) to expand circulating volume, monitoring for pulmonary edema or worsening hypertension.
Clinical Guardrails / Mimics / Pitfalls
Do not initiate salt loading before adequate α‑blockade, as it may precipitate hypertensive crisis. Avoid excessive saline (>2 L) in patients with reduced ejection fraction or renal failure. Do not use hypotonic fluids; isotonic saline is preferred. Remember that orthostatic hypotension may persist despite volume expansion due to venous pooling; assess symptoms, not just BP changes.
Concrete Clinical Example
A 52‑year‑old with biochemical PPGL (urinary metanephrine 8× ULN) starts phenoxybenzamine 10 mg BID. On day 3, BP is 138/86 seated, orthostatic drop 15 mmHg symptomatic. Diet is increased to 9 g NaCl/day; BP falls to 124/78 seated, orthostatic symptoms improve. Evening before surgery, 1.5 L saline is infused over 8 h; intra‑operatively BP remains stable 110‑130/70‑80 mmHg without vasopressor requirement.
Source: Japan Endocrine Society Clinical Practice Guideline for the Diagnosis and Management of Pheochromocytoma and Paraganglioma 2025, Tanabe et al., 2025, doi:10.1507/endocrj.EJ25-0165 (Sections I-4-4, I-4-6)