Pheochromocytoma
OVERVIEW
- paraganglioma -> catecholamine producing tumours
- associated with: MEN, von Hippel-Lindau syndrome, neurofibromatosis and familial paraganglioma
CLINICAL FEATURES
- paroxysmal hypertension
- headaches
- palpitations
- sweating
Cardiovascular Emergencies
- hypertensive crisis: provoked by posture, exertion, certain food/beverage, emotion, urinary or drugs (histamine, ACTH, metoclopramide, phenothiazines, TCA, anaesthetics) -> use phentolamine 2.5-5mg IV, GTN or SNP
- shock: abdominal pain, APO, mydriasis, weakness, diaphoresis, cyanosis, hyperglycemia -> fluid, vasopressin, ephedrine
- arrhythmia: sinus tachycardia, SVT, broad complex, VT, AF, VF -> esmolol IV
- catecholamine induced myocarditis, cardiomyopathy, obstructive hypertrophic cardiomyopathy
- myocardial ischaemia and MI: can present as an ACS but with no troponin elevations -> normal coronaries on angiography
- acute peripheral ischaemia: sudden ischaemia, necrosis, gangrene from arterial vasoconstriction
Pulmonary Emergencies
- APO: often cardiogenic and non cardiogenic in origin
Gastrointestinal Emergencies
- severe abdominal pain and vomiting
- may be acute bleed with dumping of vast amounts of catecholamines into the circulation -> embolisation
- may require surgery if causes mesenteric vasoconstriction with distal ischaemia
Renal Emergencies
- CVA
- bleed
- SAH
- seizures
Multi-system Failure
- APO, renal failure, DIC, T > 40 C, encephalopathy, hyper/hypotension
- even if critical this syndrome is indication for emergency tumour resection.
INVESTIGATIONS
24hr Urine
- fractionated metanephrines
- fractionated catecholamines
Plasma
- fractionated metanephrines
If normal -> check during a spell
Diagnosis =
- 2 fold elevation above upper limit of normal in urine catecholamines
- increased in urine metanephrines
- significant increase in fractionated plasma metanephrines
Further Investigation
- CT – less accurate for small lesion
- MRI\CT to look @ adrenals or for paraaortic mass
- 123I-MIBG if mass > 10cm
If gland normal
- whole body MRI
- 123I-MIBG
- In-III pentetreotide scan
- PET scan
MANAGEMENT
- ICU/HDU admission
- resuscitate (A, B, C)
- alpha blockade: phentolamine (acutely), phenoxybenzamine 10mg BD -> increased to 1mg/kg/day QID (10-14 days)
- then beta blockade: atenolol 25mg OD
- other agents: phentolamine, calcium channel blockers, labetalol
- MgSO4
- screen for myocardial damage: TNT, ECG, ECHO
- surgery
Criteria for Surgery:
(1) BP < 160/90 for 24 hours
(2) postural hypotension but with a BP of 80/45 upright
(3) < 1 ventricular extrasystole Q5 min
(4) no ST changes and TWI on ECG for 1 week
COMPLICATIONS
- death
- malignancy
- MI
- arrhythmias
- seizures
- CVA (ICH)
- APO
- aortic dissection
- hypertensive encephalopathy
Critical Care
Compendium
Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.
After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.
He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE. He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.
His one great achievement is being the father of three amazing children.
On Twitter, he is @precordialthump.
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