Adrenal Disease Flashcards
adrenal glands
- multifunctional and secrete variety of hormones
- located just above each kidney
two portions of adrenal gland
- cortex (80-90%)
- medulla (10-20%)
three zones of adrenal cortex
- zona glomerulosa (aldosterone)
- zona fasciculata (cortisol)
- zona reticularis (androgens)
adrenal cortex hormones
- glucocorticoids (cortisol)
- mineralocorticoids (aldosterone)
- androgens
adrenal medulla hormones
- epi (80%)
- NE (20%)
cortisol functions
- blood glucose regulation
- protein turnover
- fat metabolism
- sodium, potassium, calcium balance
- maintenance of CV tone
- modulation of tissue response to injury or infection
- survival as result of stress
hypercortisolism (cushings)
- excessive cortisol secretion
- can be ACTH dependent or ACTH independent
ACTH dependent
- cushings disease pituitary corticotroph tumors (microadenomas)
- non-endocrine tumors of lung, kidney or pancreas (ectopic corticotrophin syndrome)
ACTH independent
- primary disease involving the gland itself
- benign or malignant tumors
cushings S/S
- sudden weight gain (central)
- thickening of facial fat (moon)
- lyte abnormalities
- systemic HTN
- glucose intolerance
- menstrual irregularities
- decreased libido
- skeletal muscle wasting
- depression/insomnia
- osteoporosis
- hypercoagulable
diagnosis of cushings
- plasma and urine cortisol levels
- CRH stimulation test
- dexamethasone suppression test
- inferior petrosal sinus sampling (IPSS)
- CT and MRI once diagnosis confirmed
cushings treatment
- surgical
- irradiation
cushings anesthetic considerations
- preop eval
- positioning
- skeletal muscle weakness
- cortisol
- blood loss
- choice of agents
cushings preop considerations
- HTN
- intravascular volume
- lytes -hypokalemia, hypernatremia
- acid base status (hypokalemic metabolic acidosis
- cardiac compromise -CHF
- DM check glucose
cushings anesthetic positioning considerations
- osteoporosis and osteomalacia (vertebral compression fractures)
- obesity
- use appropriate padding
- check position during case
- care when moving to stretcher use of roller
cushings anesthetic management of muscle weakness
- hypokalemia = contributing factor (treat preop)
- decreased requirement for muscle relaxant
- use PNS
- maintain 1 twitch if possible
cushings anesthetic management of cortisol
- 100 mg glucocorticoid (hydrocort)/24 hours start in OR
- dose tapered over 3-6 days to maintenance
- mineralocorticoid may also need supplementation
- unilateral = may not require continued therapy
cushings anesthetic considerations blood loss
- may be significant
- t&s
- major surgery = t&c
- CVP and ALINE
cushings anesthetic management anesthetic agents
- some inhalation agents depress adrenal response to stress and ACTH
- etomidate - inhibits 11 Beta hydroxylase (involved in cortisol and aldosterone synthesis) = adrenocortical suppression if long term infusion
cushings anesthetic management complications
-transphenoid microadenomectomy - VAE, DI, meningitis
conn’s syndrome
- primary hyperaldosteronism
- excessive secretion of aldosterone from functional tumor
- occurs more in women than men; rare in kids
secondary hyperaldosteronism
-increased circulating serum renin stimulates release of aldosterone (renovascular hypertension)
Conn’s disease S/S
- nonspecific, some asymptomatic
- systemic HTN (HA, DBP 100-125); may be resistant to treatment
- hypokalemia (skeletal muscle cramps, skeletal muscle weakness, metabolic alkalosis)
anesthetic management of hyperaldosteronism
- correct decreased K and HTN
- assess cardiac/renal status
- avoid hyperventilation (further decreases K)
- monitors include A line
- adequate fluids with vasodilators/diuresis
- check acid/base and lytes often
- exogenous cortisol 100 mg/q 24 hours
addison’s disease
- primary adrenal insufficiency
- idiopathic/autoimmune
- no symptoms until 90% adrenal cortex destroyed
- deficiency of all adrenal cortex secretions = mineralocorticoids, glucocortiocoids, androgens
addison’s disease S/S
- chronic fatigue
- muscle weakness
- hypotension
- weight loss
- anorexia N/V/D
- increased BUN + hemoconcentration
- hyponatremia
- hyperkalemia
- hypoglycemia
- abd or back pain
- hyperpigmentation in sun exposed areas to distal extremities
addison’s disease diagnosis
- baseline plasma cortisol of <20
- cortisol level <20 after ACTH stimulation test
- NORMAL response is cortisol level >25
addisonian crisis
- triggered in steroid dependent who do not receive increased dose during stress
- stress –> circulatory collapse (hypoglycemia, lyte imbalance, depressed mentation)
addisonian crisis treatment
- IV cortisol 100 mg Q4-6H
- D5NS
- volume colloid
- whole blood
- inotropic support
exogenous steroids in addison’s before surgery
- take daily dose DOS
- minor surgery - 25 mg hydrocort
- major surgery - 100 mg bolus followed with infusion at 10 mg/hr OR 100 mg Q6H
addisons intraop hypotension management
- rule out usual causes of shock
- measure CVP, SSV or PPV –> give fluids if indicated
- treatment - vasopressor, cortisol admin (100mg), fluids, invasive monitoring
addison’s other anesthetic considerations
- measure BG often (q1h intraop)
- hypoglycemia - dextrose solution
- check lytes often
- avoid etomidate
- inhalation agents - sensitive to drug induced myocardial depression
- PNS - titrate muscle relaxants d/t skeletal muscle weakness
hypoaldosteronism
- congenital deficiency
- hyporeninemia - due to long standing DM and renal failure and/or tx with ACE-i (loss of ANG stimulation)
- nonsteroidal inhibitors of prostaglandin synthesis
hypoaldosteronism s/s
- hyperkalemic acidosis
- severe hyperkalemia
- hyponatremia
- myocardial conduction defects
hypoaldosteronism treatment
- mileralocorticoids (fludrocortisone)
- liberal sodium intake
pheochromocytoma
- catechol secreting tumor
- originates in adrenal medulla and related tissues elsewhere in body
- 95% found in abd cavity
- 90% in adrenal medulla
- 10% involve both glands
- most common in young to mid adult live (30s-50s)
pheochromocytoma predominant symptoms
- HTN continuous or paroxysmal
- HA
- diaphoresis/pallor
- palpitations/tachycardia
pheochromocytoma associated symptoms
- orthostatic hypotension
- anxiety
- tremor
- chest pain
- epigastric pain
- flushing
- painless hematuria
pheochromocytoma episodes timing
- duration - one hour or less
- frequency -daily to once every few months
pheochromocytoma diagnosis
- urine test (screening but not good for definitive diagnosis)
- plasma levels (reliable reflection of presence of pheo); measure plasma free metanephrines (breakdown products of epi and NE)
- radiographic tests to locate tumor
metanephrine levels in pheo
- normetanephrine >400
- metanephrine >220
pheochromocytoma treatment
- surgical excision = definitive treatment
- test = phenoxybenzamine or prazosin to produce alpha block
- restore intravascular volume
- restore release of insulin with alpha block
- persistant tachy-beta block (esmolol)
- DO NOT give non-selective beta block in absence of alpha block (unable to maintain CO)
pheochromocytoma preop considerations
- optimization
- history and labs
- increased PVR –> myocardial ischemia, ventricular hypertrophy, CHF, cardiomyopathy
- hx cerebral hemorrhage
- hyperglycemia
pheochromocytoma preop criteria
- no BP >165/90 for 48 hours before surgery
- BP on standing should not be <80/45
- ECG without ST-T wave changes
- no more than 1 PVC Q5min
pheochromocytoma anesthetic considerations
- good communication with surgeon
- continue adrenergic blocks
- fluid management
- heave premed with benzos and opioids
- gentle positioning (bc compression can cause release of catechols)
pheochromocytoma anesthetic technique
- combined GA/continuous labor epidural
- epidural prior to induction
- invasive monitoring
pheochromocytoma anesthetic considerations induction
- prepare for hyperdynamic BP
- lido 1-2 mg/kg
- no mso4 - histamine release can stimulate release of catechols
- sufenta - 0.5-1 mcg/kg
- fent - 3-5 mcg/kg
- prop - 3 mg/kg
pheochromocytoma intraop considerations
- inhalation agent for maintenance (des and sevo)
- 1.5-2 MAC more control than opioid technique
- combined technique with epidural
- opioid
- muscle relaxation (vec/roc)
pheochromocytoma blood pressure control intraop
- nitroprusside (preferred)
- phentolamine
- mag sulfate
- calcium channel blockers
pheochromocytoma heart rate control
- beta blockade
- esmolol = best
- labetalol
- metoprolol
surgical ligation of pheo’s venous drainage causes what?
- decreased catechols - hypotension
- stop antihypertensives
- decreased inhalation agent
- volume FIRST
- then pressors - phenyl, NE, dopa
- combined regional and GA will decrease hypotension
- persistant hypotension = may require NE infusion until body can adapt to decreased level of alpha stim
pheochromocytoma drugs to avoid
- histamine releasers (MSO4, atracurium)
- halothane -sensitizes myocardium to epi
- succ -fasiculations of abd muscles may release catechols
- panc and atropine
- metoclopramide (catechol release in pheo via stimulation of 5HT4 receptors on surface of pheo)
pheochromocytoma post op considerations
- analgesia - CLE, PCA, opioids
- 50% patients remain hypertensive
- early extubation
- hypoglycemia
- steroid supplementation
- post op HTN (presence of other tumors, vol overload, continue to monitor)
- adequate pain control
