| name | ppgl-preoperative-alpha-blocker-selection |
| description | Selects preoperative alpha-blocker therapy and establishes initial dosing regimen for PPGL blood pressure control. Triggered by biochemically confirmed PPGL requiring surgery, patient needs preoperative blood pressure control, or preparing for adrenalectomy in PPGL patient. |
Preoperative Alpha-Blocker Selection and Initial Dosing for PPGL
STEP 1 — Gather Information
Collect biochemical confirmation of PPGL (elevated fractionated metanephrines or catecholamines), document clinical need for preoperative BP control, note planned surgery/adrenalectomy, record baseline BP and HR, assess orthostatic hypotension risk, review concomitant medications (especially drugs affecting catecholamine metabolism).
STEP 2 — Rule In / Rule Out
Is catecholamine overproduction biochemically confirmed? If yes, proceed to alpha-blocker initiation; if unclear, perform a comprehensive clinical assessment before considering alpha-blockers (per I-4-5).
STEP 3 — Classify or Stratify
For confirmed PPGL, select a selective alpha-blocker (e.g., doxazosin) as first-line; if BP reduction insufficient, add a calcium antagonist or metyrosine; if tachycardia/tachyarrhythmia present, add a beta-blocker only after adequate alpha-blockade.
STEP 4 — Decide
Initiate selective alpha-blocker (doxazosin 1–2 mg PO daily) at bedtime; titrate every 2–3 days to target BP <130/80 mmHg and HR 60–70 bpm sitting; add calcium antagonist or metyrosine if needed; start normal salt diet (9 g/day) or saline infusion (1–2 L) on the third day of alpha-blocker therapy; continue for at least 7–14 days preoperatively.
Clinical Guardrails / Mimics / Pitfalls
Do not administer a beta-blocker before an alpha-blocker (risk of hypertensive crisis); avoid nonselective alpha-blockers (phenoxybenzamine) as unavailable in Japan; do not use alpha-blockers if catecholamine overproduction is unclear without comprehensive assessment; monitor for orthostatic hypotension after the first dose; avoid abrupt withdrawal of alpha-blockers perioperatively.
Concrete Clinical Example
A 45-year-old with biochemically confirmed PPGL (urinary normetanephrine 5× ULN) scheduled for laparoscopic adrenalectomy in 10 days starts doxazosin 1 mg at bedtime, titrates to 4 mg daily over 6 days, achieves BP 122/78 mmHg, adds amlodipine 5 mg if needed, maintains normal salt diet, and proceeds to surgery with stable vitals.
Source: Japan Endocrine Society Clinical Practice Guideline for the Diagnosis and Management of Pheochromocytoma and Paraganglioma 2025, Japan Endocrine Society, 2025, doi:10.1507/endocrj.EJ25-0165
