Pheochromocytoma Flashcards
What are pts with pheo at risk for?
cerebral hemorrhage, pulmonary edema, MI, ventricular arrhythmias, and renal failure
Potential for ____ after tumor excision?
Potential for refractory hypotension following tumor excision
what is pheo associated with?
Association with multiple endocrine neoplasia (thyroid and parathyroid CA, insulinomas, mucosal adenomas), and Von hippel landau disease
Do patients have flushing in pheo?
NO
what would you see on physical exam of pheo?
tremor/orthostatic vitals
What kind of lab tests/imaging would you order?
Free NE in 24 hour urine +/- urine VMA
CBC (increased Hgb from volume contraction), decreased K+ can happen.
Glucose, EKG, echo (rule out CHF) CT abdomen/pelvis for tumor
How do you optimize patients with PHeo?
alpha blockade as an outpatient (doxazosin 1 mg po x 10-14 days, can increase up to 16 mg
What are BP goals in pheo?
no BP >165/95, and no less than 80/45
may need beta blockade if increased HR/dysrhythmias but ONLY AFTER BETA BLOCKADE
Goals in pheo:
minimize stimulation of catecholamine release, smooth intubation
avoid drugs with sympathetic stimulation/histamine release (morphine, meperidine, ketamine)
Options for anesthesia in pheo:
Do you want an ICU/stepdown bed?
GA +/- epidural if open. Neuraxial can exacerbate hypotension after pheo is removed
Yes-ICU stepdown yes
Room setup for pheo:
a-line, +/- CVP, PAC/TEE as indicated
phentolamine, labetalol, phenylephrine prepared
Induction in pheo:
Maintenance in pheo:
quiet unhurried induction, deep intubation
Maintenance: volatile, opioid, blood sugar periodically
Disposition/pain for pheo:
to ICU/stepdown for continuous monitoring, epidural for post op analgesia if open procedure
Why are we not using phenoxybenzamine for pheo anymore?
because it is a non-selective alpha blocker: Alpha 2 antagonism: uninhibited release of NE at cardiac sympathetic nerve endings–>unwanted increased chronotropy and inotropy
- sedation and postoperative somnolence
- orthostatic hypotension
When should the last dose of selective alpha 1 antagonists (doxazosin) be given?
10 pm the evening before surgery.
