Anesthesia for patients with adrenal disease Flashcards
The adrenal cortex releases
glucocorticoids–> cortisol
mineralocorticoids–> aldosterone
androgens
Describe the percentage of epinephrine and norepinephrine in the adrenal medulla
epinephrine 80%
norepinephrine 20%
The adrenal glands are
multifunctional and secrete a variety of hormones
The two portions of the adrenal gland are the
cortex 80-90% (zona glomerulosa, zona fasciculata, zona reticularis)
medulla 10-20%
There is complex regulation in the adrenal glands which is through the
hypothalamus–> anterior pituitary–>adrenal cortex
Physiological functions of the adrenal glands includes
blood glucose regulation
protein turnover
fat metabolism
sodium, potassium, and calcium balance
maintenance of cardiovascular tone
modulation of tissue response to injury or infection
survival as a result of stress (most important)
Cushings syndrome is the result of
excessive cortisol secretion
Excessive cortisol secretion can be
ACTH dependent or
ACTH independent
ACTH dependent excessive cortisol secretion includes
Cushings disease pituitary corticotroph tumors (microadenomas)
non endocrine tumors of lung, kidney, or pancreas ectopic corticotropin syndrome
ACTH independent excessive cortisol secretion includes
benign or malignant adrenocortical tumors
Signs and symptoms of Cushing’s disease include
sudden weight gain (usually central) thickening of the facial fat "moon face" electrolyte abnormalities systemic hypertension glucose intolerance menstrual irregularities decreased libido skeletal muscle wasting depression and insomnia osteoporosis hypercoagulable
Diagnosis of Cushing’s syndrome and disease can be performed through
plasma & urine cortisol levels- 24 hour urine collection, plasma cortisol levels; if both elevated it indicates Cushing's syndrome CRH stimulation test dexamethasone suppression test inferior petrosal sinus sampling CT & MRI once diagnosis is confirmed
Treatment of Cushing’s syndrome is dependent
upon the cause
includes:
surgical-transphenoidal microadenectomy & adrenalectomy
irradiation
Anesthetic management considerations for patients with Cushing’s syndrome includes
preop evaluation positioning skeletal muscle weakness cortisol blood loss choice of agents
Preoperative considerations for the patient with Cushing’s syndrome includes
HTN, intravascular volume, electrolytes- hypokalemia & hypernatremia; acid-base status- hypokalemic metabolic alkalosis; cardiac compromise- CHF; diabetes- check glucose level- control with small amounts of IV insulin
Positioning considerations for the patient with Cushing’s syndrome includes
osteoporosis & osteomalacia- vertebral compression fractures–> be careful with airway positioning
obesity
use appropriate padding
check position throughout the case
care when moving to stretcher use of roller
Anesthetic considerations related to muscle weakness for the patient with Cushings syndrome includes
hypokalemia-contributing factor
decreased requirements for muscle relaxants
use a peripheral nerve stimulator
maintain 1 twitch if using neostigmine for reversal
w/ LMA may not be able to breath adequately
Describe the use of cortisol for the patient with Cushing’s syndrome.
unilateral or bilateral adrenalectomy–> hydrocortisone usually started intraoperatively, dose reduced over 3-6 days to maintenance dose, mineralocorticoid may also need supplementation, unilateral continue therapy may not be required depending upon remaining gland
Blood loss for adrenalectomy for the patient with Cushing’s icnludes.
may be significant T&S major surgery- T&C CVP A-line
Anesthetic agents for the patient with Cushings disease include
drugs or techniques not likely to influence attempts to decrease cortisol levels–> some inhalation agents depress adrenal response to stress & ACTh
etomidate inhibits enzymes involved in cortisol & aldosterone synthesis
The changes in ACTH caused by anesthetic agent or type are
insignificant when compared to increase in cortisol secretion with surgical stress
Complications of transphenoidal microadenomectomy include
VAE, transient diabetes insipidus, & meningitis
Complications with adrenalectomy are related to
laparoscopic–> position, insufflation
open–> pulmonary complications d/t retractors leading to atelectasis
Conn’s syndrome is
excess secretion of aldosterone from a functional tumor
Conn’s syndrome occurs more in
women than men; rarely in children
Conn’s syndrome results in
secondary hyperaldosteronism as a result of increased circulating serum renin stimulating the release of aldosterone
Signs & symptoms of Conn’s disease are
non-specific & some are asymptomatic
may also include systemic hypertension & hypokalemia
Systemic hypertension in Conn’s disease reflects
aldosterone induced sodium retention and resulting increased fluid retention. MAY BE RESISTANT TO TREATMENT
may see headache, diastolic BP 100-125 mmHg
Anesthesia management for the patient with hyperaldosteronism as a result of Conn’s disease includes
correct decreased K+ & HTN- spironolactone
assess cardiac/renal status
avoid hyperventilation–> further decreases K+
monitors: a-line
adequate fluids w/ vasodilators/diuresis
check acid-base, electrolytes frequently
exogenous cortisol 100 mg/q 24 hours
Addison’s disease is a result of
primary adrenal insufficiency due to
idiopathic/autoimmune most common primary cause
There are no symptoms of Addison’s disease until
90% of adrenal cortex has been destroyed
Addison’s disease results in deficiency of
all adrenal cortex secretions including mineralocorticoids, glucocorticoids, and androgens
Signs & symptoms of Addison’s disease include
chronic fatigue, muscle weakness, hypotension, weight loss, anorexia, N/V, diarrhea, increased BUN & hemoconcentration due to hypovolemia; hyponatremia, hyperkalemia, hypoglycemia, abdominal or back pain, hyperpigmentation in sun-exposed areas and the distal extremities
Diagnosis of Addison’s disease is from
baseline plasma cortisol level <20 ug/dL
Cortisol level <20 ug/dL after ACTH stimulation test
- cortisol levels are measured 30 & 60 minutes following administration of ACTH
-positive test yields a poor response to ACTH & is indicative of adrenal cortex impairment
Addisonian crisis is triggered in
steroid-dependent individuals who do not receive increased dose during stress
Stress for the patient with Addisonian crisis can result in
circulatory collapse including hypoglycemia, electrolyte imbalance, and depressed mentation
Treatment of Addisonian crisis includes
IV cortisol for 24 hours
D5 0.9% NS
volume- colloid, whole blood
inotropic support
Anesthetic management considerations for the patient with Addison’s disease include
administer exogenous corticosteroids
if on a daily dose- patient should take day of surgery
recommended dose for surgery is 25 mg for minor
100 mg bolus or 100 mg q6 for major
For the patient with Addison’s disease who develops intraoperative hypotension,
rule out usual causes of shock
measure CVP- fluids
Treating intraoperative hypotension for the patient with Addison’s disease includes
vasopressor- even if it did not have effect before cortisol
administer cortisol 100 mg IV
fluids
invasive monitoring
Anesthetic management considerations for the Addison’s disease patient regarding electrolytes includes
measure glucose levels preop & every hour
hypoglycemia- replace with dextrose solutions
check electrolytes frequently- potassium levels a concerns (consider avoiding LR)
Anesthetic management considerations for the Addison’s disease patient in regards to anesthetic medications include:
avoid etomidate
inhalation agents- sensitive to drug induced myocardial depression
PNS- titrate muscle relaxants due to skeletal muscle weakness
Hypoaldosteronism is a result of
congenital deficiency
hyporeninemia
nonsteroidal inhibitors of prostaglandin synthesis
Describe how hyporeninemia results in hypoaldosteronism.
due to long standing diabetes & renal failure and/or treatment with ace inhibitors–> loss of angiotensin stimulation
Describe how nonsteroidal inhibitors of prostaglandin synthesis result in hypoaldosteronism.
May inhibit renin release and exacerbate condition in presence of renal insufficiency
Signs and symptoms of hypoaldosteronism includes
hyperkalemic acidosis
severe hyperkalemia
hyponatremia
myocardial conduction defects
Hypoaldosteronism treatment includes
mineralocorticoids- fludrocortisone
liberal sodium intake
A pheochromocytoma is a
*** catecholamine-secreting tumor
A pheochromocytoma originates in the
adrenal medulla and related tissues elsewhere in the body
- about 90% originate in adrenal medulla with 10% involving both adrenal glands
- most common in young to mid adult life
Predominant symptoms of pheochromocytoma include
continuous or paroxysmal HTN
headache
diaphoresis/pallor
palpitations/tachycardia
Associated symptoms of pheochromocytoma
orthostatic hypotension, anxiety, tremor, chest pain, epigastric pain, flushing (rare), painless hematuria (rare)
The timing of episodes for pheochromocytoma include
duration: one hour or less
frequency: daily to once every few months
Diagnosis of pheochromocytoma is through
urine tests- useful for screening but unreliable for definitive
plasma levels- reliability reflects the presence of pheo (more neo than epi!)
radiographic tests to locate tumor-CT/MRI
Treatment of pheochromocytoma includes
surgical excision
restore intravascular volume–> decreased Hct evident
restore release of insulin with alpha block
persistant tachy-beta block (esmolol)
test: phenoxybenzamine (alpha 1 & 2) or prazosin (selective alpha 1)
With pheochromocytoma, it is important to NOT administer
non selective beta block in the absence of alpha-block-heart depressed by beta block b/c unable to maintain CO w/ unopposed alpha mediated vasoconstriction
Pertinent preop history & labs for the pheochromocytoma patient includes
increased PVR–> myocardial ischemia, ventricular hypertrophy, CHF, cardiomyopathy
history of cerebral hemorrhage
hyperglycemia- decreased circulating insulin with increased glycogenolysis
Preop criteria for the patient undergoing pheochromocytoma includes
no BP reading >165/90 for 48 hours prior to surgery
BP on standing should not be <80/45
ECG without ET-T wave changes that are not permanent
No more than 1 PVC q 5 min.
Fluid management for the patient with pheochromocytoma includes:
hypovolemic- pre-hydrate
falsely elevated HCT–> T & C
renal function
fluid replacement plan (4/2/1)
Additional anesthetic considerations for the pheochromocytoma patient include
good communication with the surgeon b/c need to know when to expect hypotension
continue adrenergic blockade- depends on surgeon as may be d/c’ed prior to surgery
Anesthetic techniques for the patient with a pheochromocytoma includes
heavy premedication with benzos & opioids
gentle positioning
anesthetic technique- combined GA/ continuous lumbar epidural, epidural prior to induction, invasive monitoring
Monitors utilized for pheochromocytomas include:
EKG
A-line- BP control, ABGs, electrolytes, glucose levels
Swan ganz/ TEE- depends on cardiac status
CVP
U/O
temperature
peripheral nerve stimulator
When preparing for hyperdynamic blood pressure with pheochromocytoma, consider the following medications:
lidocaine 1 to 2 mg/kg
propofol 3 mg/kg
opioids- do not administer morphine due to histamine release (stimulates catecholamine release)- sufentanil 0.5 to 1 mcg/kg or fentanyl 3 to 5 mcg/kg
Laryngoscopy considerations for the patient with pheochromocytoma include
must have adequate depth- inhalation agent to deepen lidocaine IV 1-2 mg/kg 1 min. before opioid fentanyl 100-200 mcg nitroprusside 1-2 mcg/kg phentolamine-alpha blockers beta blocker- esmolol no drugs that release histamine
Intraoperative blood pressure control for the pheochromocytoma patient includes
nitroprusside–> preferred
phentolamine- tachyphylaxis, tachycardia, & longer duration
magnesium sulfate
calcium channel blockers
Heart rate control for the patient with pheochromocytoma includes
esmolol-preferred
labetalol
metoprolol
Intraoperative management of the patient with pheochromocytoma includes:
inhalation agent for maintenance- O2/air (desflurane- avoid d/t tachycardia, sevoflurane)
1.5-2 MAC more control than opioid technique
combined technique with epidural
opioid
muscle relaxant- vecuronium/rocuronium
Drugs to avoid with pheochromocytoma include
histamine releasers- morphine, atracurium
halothane- sensitizes myocardium to epinephrine
succinylcholine- fasciculations of abdominal muscles may cause release of catechols from tumor
pancuronium & atropine
metoclopramide
With surgical ligation of pheochromocytoma tumor’s venous drainage it results in
decreased catechols so prepare for hypotension by:
stopping antihypertensives
decrease concentration inhalation agent
volume first- crystal/colloids
administer pressors- phenylephrine, norepinephrine
combine RA/GA decreases hypotension- adequate volume replacement preoperatively
Persistent hypotension with pheochromocytoma may require an
infusion of norepinephrine until the vasculature can adapt to decreased levels alpha stimulation
Postoperative considerations for the patient with pheochromocytoma include
analgesia- CLE, PCA, opioids
50% of patients will remain hypertensive- continue antihypertensive therapy, elevated catecholamine levels for 10 days postop
early extubation- young, no lung involvement
Describe postoperative considerations for pheochromocytoma regarding glucose control
hypoglycemia- excess insulin release and ineffective lipolysis and glycogenolysis
Describe postoperative considerations for pheochromocytoma regarding steroid supplementation.
bilateral adrenalectomies or hypoadrenalism requires steroid supplementation
Describe postoperative considerations for pheochromocytoma regarding postoperative HTN.
presence of occult tumors
volume overload
continue monitoring
