6901 endo Flashcards
Examples of peptide hormones?
insulin, ADH, angiotensin, erythropoeitin, GH
How are peptides released in to the blood stream?
exocytosis of granules they’re stored in and released in to ECF
Some examples of amine hormones?
catecholamines (epi, serotonin, norepi, dopa) and thyroxine
Lipid hormones are derived from where?
cholesterol
Are lipid hormones stored in granules? What are they bound to? What effect does that have?
no; bound to plasma proteins which delays their metabolism
Examples of lipid hormones?
aldosterone, estrogen, progesterone, adrenalcorticoids-cortisol, aldosterone
How are lipids transported?
simple diffusion
Where are hormone receptors located?
on the surface of the cell or inside the cell
Hormone receptors display a high affinity for what?
right hormone
What directs the hormone to the correct target organ?
location receptor
How do peptide and protein hormones exert their effects?
interact by activating the receptor site on the cell surface, and it generates a 2nd receptor (often cAMP)
3 hormones which use cAMP (there are others)?
vasopressin, TSH, parathyroid hormone
What are 2 other 2nd messengers?
Ca, cyclic GMP
How do lipid hormones exert their effects?
they attract specific hormones in various locations and since they’re lypophillic they diffuse in to the cell
Hormone receptor number is inversely related to?
concentration of circulating hormone
Hormone secretion and suppression are caused by what three things?
biorhythms (circadian), neural controls (pain, smell, taste), feedback
Homeostasis is controlled by what 2 systems?
endocrine and nervous
6 functions endocrine system regulates?
behavior, growth, metabolism, fluid status, development, reproduction
The 8 endocrine glands are?
pancreas, thyroid, parathyroid, adrenal glands, placenta, testes, ovaries, pituitary gland
This gland secretes hormones that effect all other endocrine glands?
pituitary
4 functions of pituitary gland?
homeostatic, developmental, metabolic, and reproductive
How big is the pituitary gland?
small, size of pea, 500 g
Where is the pituitary gland located?
base of brain in sella turcica
What structure connects the pituitary gland to the hypothalamus?
hypophyseal stalk
The pituitary gland is between the ______ _______ and the _____ ________
optic chiasm, optic tracts
What regulates hormone release from the anterior and posterior pituitary?
hypothalamus
Another name for the anterior pituitary and the posterior pituitary?
adenohypophysis; neurohypophysis
Why is the posterior pituitary unique?
it receives synthesized hormones from the hypothalamus
6 hormones released from anterior pituitary?
GH, ACTH, thryotropin (TSH), FSH, LH, prolactin
How does GH act?
similarly to insulin-metabolic and endocrine ftns thruout the body- skeletal muscle development, growth, carb, and protein metabolism regulation
What does ACTH do?
stimulates release of cortisol and androgens from adrenal glands
What does thyrotropin do?
growth and metabolism of thyroid gland and stimulates thyroid gland to release TH/thyroid hormones
What does FSH do and where is it secreted?
stimulates estrogen production and ovarian follicle development in females and is secreted from ovaries and spermatogenesis in males
What does LH do?
stimulates progesterone production and ovulation and corpeus luteum in females and testosterone production and spermatogenesis in males (??)
What does prolactin do?
stimulates lactation from mammary glands, mammary gland development, inhibits synthesis and secretion of LH and FSH, this hormone is markedly increased during pregnancy
What % of the pituitary gland is the anterior lobe?
80%
5 causes of hyposecretion from the anterior pituitary gland?
large nonfunctional pituitary tumors, postpartum shock/Shehan syndrome, irradiation, trauma, hypophysectomy (surgical removal of pituitary gland)
What is panhypopituitarism?
lack of pituitary hormones rather than just lack of 1 and it’s more common than lack of 1
What 3 hormones are commonly effected with panhypopituitarism?
TSH, ACTH, gonadotropic hormones
5 manifestations of congenital anterior hypopituitarism?
micropenis, midline defects, optic atrophy, hypoglycemia, poor growth
A decrease in what hormone leads to decrease in thyroid function?
TSH
What hormone would decrease glucocorticoid production by the adrenal cortex?
ACTH
A decrease in what hormone would cause a depressed sexual development and reproductive function?
gonadotropic hormone secretion
Hormone deficiency symptoms: hypoglycemia, vomiting, malaise?
cortisol
Hormone deficiency symptoms: fatigue, constipation, cold intolerance, bradycardia?
thyroxine
Hormone deficiency symptoms: delayed puberty, amenorrhea, micropenis?
sex steroids
Hormone deficiency symptoms: short stature, hypoglycemia?
growth hormone
Hormone deficiency symptoms: polyuria, polydyspsia, hypernatremia, lethargy, dehydration?
ADH
A treatment of hypopituitarism? What 2 meds may be required afterwards?
surgical removal- steroids, thyroid hormone replacement
What do you have to watch out for after surgical removal of the pituitary and what’s the treatment for that?
DI- vasopressin
Usual approach for removal of pituitary? Whats the other approach?
transphenoidal/nasal; transcranial
Why is a precordial particularly important for surgical pituitary removal?
to detect venous air embolism bc in sitting position (low ETCO2)
What gas do you need to avoid for removal of ant pituitary? Why?
N20; surgeon injects air and N20 is more soluble than nitrogen so it diffuses in more quickly and can expand a closed space
Do you want muscle relaxation for surgical removal of pituitary?
yes
Why do you need a quick, smooth emergence for surgical removal of pituitary? And what can help facilitate that?
allow for neuro checks; give lido to prevent bucking
Why would BP increase during removal of pituitary?
surgeon injects local with epi
What should you prepare the pt for post operatively if having pituitary removed?
will have nasal packing and feel congested/pressure
Potential complications of transphenoidal pit removal and which ones are not common?
meningitis, CSF leak, ischemic stroke, visual loss; not common: epistaxis, symptomatic hyponatremia, transient DI, cranial nerve damage
Most pituitary tumors are?
hypersecreting pituitary adenomas
What is a common hormonal abnormality associated with pituitary adenomas?
excessive prolactin secretion with lacturia
The most common hypsersecretion pituitary tumors secrete what 3 hormones?
prolactin, ACTH, GH
ACTH excess is called?
Cushing’s disease
Prolactin secreting tumors produce what 3 effects?
infertility, amenorrhea in women, and decreased libido in men
What med can you treat decreased libido with?
bromocriptine (dopamine agonist)
Other name for GH?
somatotropin
Releasing and inhibiting hormones from where regulate GH activity throughout the day?
hypothalamus
How do the levels of GH change throughout one’s lifetime?
rate of secretion is increased in childhood, followed by an even greater rise in adolescence. levels plateau in adulthood and drop in old age
What increases amt of GH secreted?
stress- OR, hypoglycemia, exercise, deep sleep
How is GH regulated?
- feedback
How does GH increase blood glucose levels?
decreases the sensitivity of cells to insulin and inhibits glucose uptake in to the cells
T/F: Feedback can be initiated by the peripheral target cells to only the hypothalamus?
F: feedback can be initiated to the pituitary too
What is hypersecretion of GH usually caused by?
GH secreting pituitary adenoma
Hyposecretion of GH is called what? And what does that do to blood sugar?
dwarfism, hypoglycemia
If sustained hypersecretion of GH occurs after adolescence it is referred to as?
acromegaly
If GH secretion is elevated before adolescence it is called?
gigantism
What effects does acromegaly have on the bone, organs, lung volumes, and facial features?
bone gets thicker and larger, organs are enlarged (kidneys, spleen, heart, liver), lung volumes increase (increase VQ mismatch with increased extrathoracic obstruction), coarse facial features
Treatment of hypersecretion of GH?
removal of pituitary tumor
4 cardiac conditions associated with acromegaly?
CM, HTN, accelerated atherosclerosis, LVH
2 endocrine abnormalities from acromegaly?
glucose intolerance, DM
Some anesthetic considerations for pt w hypersecretion of GH?
may need to size ETT down by 1, may have difficult mask fit d/t enlarged facial features, may be difficult DL d/t macroglossia/ tissue overgrowth, extubate pt when fully alert, >60% pts have sleep apnea, monitor blood glucose and lytes, be careful w positioning bc have entrapment and neuropathies
Posterior pit gland secretes what 2 hormones?
ADH, oxytocin
increased serum osmolarity= __ ADH?
increased
This hormone stimulates milk ejection during lactation?
oxytocin
This hormone controls water reabsorption and excretion in the kidney
ADH
This hormone stimulates uterine smooth muscle contraction?
oxytocin
Derivatives of oxytocin are used for what 2 things in L&D?
inducing labor, decreasing postpartum bleeding
What receptor does ADH act on in renal collecting ducts?
V2
ADH is released at which mOsm/L value?
284
Normal mOsm/L?
285-290
2 things that stimulate ADH release?
10-20% decrease in plasma volume or blood pressure
ADH secretion increases with what 4 things?
pain, hemorrhage, emotional stress, nausea
Which organ increases ADH synthesis and release?
hypothalamus
Baroreceptors send signals via which nerves to the hypothalamus to tell the hypothalamus to increase ADH synthesis and release?
vagus, glossopharyngeal
DI hallmark symptoms?
polyuria, polydypsia
DI leads to dehydration and what type of Na balance?
hypernatremia
DI has what type of concentration of ADH?
low
Normal urine osm values? And what are they in DI?
500-800;
2 types of DI?
neurogenic-destruction of post pit where there is inadequate secretion of ADH and nephrogenic- inability of renal collecting duct receptors to respond to ADH
S/S DI?
hyperreflexia, weakness, lethargy, seizures, coma
The difference in the 2 types of DI is the response to desmopressin. In neurogenic, desmopressin does what? In nephrogenic desmopressin does what?
neurogenic: concentrates urine; nephrogenic: does not concentrate urine
DI after pituitary gland surgery is generally d/t reversible trauma to posterior pituitary and is ______?
transient
Treatment for DI short term and long term?
short term- vasopressin; long term- desmopressin
Is vasopressin admin before surgery necessary with partial DI?
usually not because ADH is released in response to surgery
What 3 parameters should be measured qh and in recovery for patients with DI?
UO, plasma osm, serum Na
What does treatment of complete DI target?
increasing receptor response to ADH
What type of fluids for DI unless serum osm reaches 290, then what?
isotonic; then hypotonic fluids
What happens in SIADH in the renal tubules when there is hypoosmolarity?
water is reabsorbed in renal tubules
Emergence may be slow/fast in SIADH pt?
slow
4 s/s of SIADH?
weight gain, increased skeletal muscle weakness, mental confusion, convulsions
4 drugs associated with increased ADH release?
tricyclic antidepressants, tegretol, diabanase, nicotine
6 causes of SIADH?
hypothyroidism, pulmonary neoplasia, head trauma or infection, intracranial tumors, posterior pituitary surgery, ADH secreting neoplasms (small cell carcinoma of the lung)
Treatment for mild SIADH and severe SIADH?
mild: fluid restriction (800 mL/day); severe w neuro s/s: hypertonic saline with lasix
Serum osmolarity in SIADH vs DI?
SIADH 290
Serum Na in SIADH vs DI?
SIADH 145
Gland that helps regulate Ca balance?
thyroid
Where is the thyroid gland located?
immediately below the larynx and on either side of and anterior to trachea
What does the thyroid gland need to produce the hormones?
iodide
Which 2 nerves are in intimate proximity to thyroid gland?
RLN, external motor of SLN
The thyroid gland is composed of follicles filled w what?
thyroglobulin, an iodinated protein that serves in thyroid hormone synthesis
What 3 hormones does the thyroid gland secrete?
T3, T4, calcitonin
Does the thyroid gland have much blood supply?
yes it has a very rich blood supply
Thyroxine/T4 is what % of thyroid hormone and is it potentn in the blood?
93% and it’s less potent in the blood
T3 is what % of thyroid hormone and is it potent in the blood?
7% and it’s more potent in the blood
Normal adult level of T3 and T4?
T3- 70-132; T4- 5-12
How is iodine absorbed in to the blood?
it’s reduced to iodide in the GI tract then absorbed in to the blood
How does iodide trapping occur?
when active transport carries iodide into the thyroid follicular cell
Where is iodide converted to oxidized iodine?
thyroid
Why does iodide need to be converted to oxidized iodine?
it is capable of combining w tyrosine residues of thyroglobulin
Normal quantities of thyroid hormone depend on?
exogenous iodine
Which T hormone (hormone) is converted to the other T hormone?
T4 is converted to T3 at the tissue sites
Which thyroid hormone primarily inhibits TRH and TSH in negative feedback?
T3
How do T3 and T4 have a direct effect on the heart?
+ inotropic and chromotropic, which may decrease the vascular tone and MAP, causing activation of renin aldosterone system , which increases the circulating blood volume and CO
This hormone stimulates every tissue in the body to produce proteins and increase the amt of O2 used by the cells?
thyroid
Peak age of Grave’s Disease?
40
Amiodarone is rich in what and therefore can cause what?
iodine; hypo or hyperthyroidism
TSH and T4 diagnosis for thyrotoxicosis?
decreased TSH, increased T4
Some etiologies of Grave’s disease?
benign follicular adenoma, iodine excess, thyroid hormone OD, goiter, thyroiditis, TSH secreting pituitary tumor, thyroid cancer
These drugs inhibit thyroid hormone synthesis?
methimazole, propylthiouracil, carbimazole
These drugs prevent thyroid hormone release?
K, sodium iodide
These drugs mask signs of over adrenergic activity in hyperthyroidism?
atenolol, propranolol
This destroys thyroid cell function?
radioactive iodine
What happens to hair, breasts, fingers, and extremities in hyperthyroidism?
fine straight hair, enlarged breasts, clubbing fingers, localized edema
Some preop anesthetic considerations for hyperthryoidism?
thyroid enlargement may cause tracheal deviation, awake fiberoptic intubation with LA may be necessary, blood volume is increased, peripheral resistance is increased, and pulse pressure is wide, ask ab hoarseness, cough, pressure in the neck, dyspnea
3 anesthetic drugs to avoid with hyperthyroidism?
ketamine, cisatracurium, atropine
Is there an increase in MAC with hyperthyroidism? Explain
no, but the increased CO and blood volume may increase the inhalational requirements
How should you intubate a pt in hyperthyroidism?
in deep level of anesthesia
How should one treat intraoperative hypotension in pt with hyperthyroidism?
w direct acting like phenylephrine bc the indirect acting can increase catecholamines
What 2 acid base symptoms stimulate SNS and should be avoided in those with hyperthyroidism?
hypercarbia, hypoxia
Why do you have to position hyperthryoidism pts carefully?
decreased bone density and predisposition to osteoporosis
What do you have to keep in mind regarding NMB in pts with hyperthyroidism?
usually don’t use them after induction unless surgeon requests them and there is an increased incidence of myopathies and myasthenia gravis in those w hyperthyroidism so titrate them carefully
ETT with NIM monitoring is used for hyperthyroidism surgeries because?
to assess RLN
ETT with NIM: red and blue electrodes should be where?
right on right, blue on left
Most serious threat to hyperthyroidism pt undergoing surgery?
thyroid storm
3 events that may precipitate thyroid storm?
trauma, surgery, labor & delivery
Thyroid storm presentation is similar to what 4 things?
pheo, MH, light anesthesia, NMS
Mortality rates of thyroid storm are as high as what?
30%
3 s/s of thyroid storm during surgery?
fever > 38.5, HTN, afib, tachycardia
Other s/s thyroid storm in awake pt?
agitation, confusion, tremor, N/V, CHF, shock/metabolic acidosis, abnormal LFTs
Treatment for thyroid storm?
cooling (Tylenol), IV hydration with glucose containing fluids, beta blockers, K iodide (block release of T3, T4), antithyroid drugs (PTU or methimazole), glucocorticoids (cortisol), correct electrolyte and acid base balances
3 post op complications w hyperthyroid pt?
RLN damage, hematoma, hypothyroidism
S/s unilateral RLN damage? S/s bilateral RLN damage?
unilateral: hoarseness; bilateral: aphonia and stridor (reintubate)
Hypoparathyroidism will occur how long after hyperthyroidism surgery?
24-72 h
Which problem, MH or thyroid storm is more of a hypermetabolic state?
MH
Differentiating s/s of MH versus thyroid storm?
MH is sudden unexplained rise in ETCO2, trismus, and RAPID temp rise; temp will usually rise later in thyrotoxicosis
6 causes of hypothyroidism?
autoimmune mediated inflammation, iodine deficiency (lithium), medications, surgery for hyperthyroid, neck irradiation, radio iodide therapy
Diagnosis of primary hypothyroidism versus secondary hypothyroidism?
primary: decreased T4 and or T3, increased TSH; secondary: decreased T4, T3, TSH
95% of all hypothyroidism cases are?
Hashimoto thyroiditis
Treatment of hypothyroidism involves replacement of which hormone?
T4
Some unthought of s/s of hypthyroidism?
CHF, gastroparesis, hypoventilation, hyponatremia, poor mentation
What happens to the hairline, tongue, and muscles in hypothryoidism?
receding hairline, thick tongue, muscle aches and weakness
Late clinical manifestations of hypothyroidism?
bradycardia, wt gain, subnormal temp, decreased LOC, thickened skin, cardiac complications
Careful eval of airway is needed for what 3 reasons in hypothyroidism pts?
enlarged thyroid gland, enlarged tongue, myexedematous infiltration of vocal cords
What are 2 reasons that pts with severe hypothyroidism are at risk for problems during surgery?
myocardial ftn and baroreceptor ftn may be depressed
Is MAC in hypothyroid pts affected?
no
Why would RSI be good in hypothyroid pt?
increased risk of aspiration d/t slower gastric emptying
A good medication for induction in hypothyroid pt?
ketamine
Why is respiratory depression following administration of opioids a possibility w hypothyroid pts?
baroreceptor response to hypercarbia and hypoxia may be depressed; large tongue and goiter hypoxia and hypercarbia may be present
What cardiac effects may be present in hypothyroid pt?
hypotension, myocardial depression, plasma volume may be reduced
If hypothyroid pt is experiencing muscle weakness what do you need to keep in mind?
may be sensitive to nondepolarizers
What medication may be necessary intraoperatively in hypothyroid pt d/t potential for adrenal insuffiency r/t stress?
cortisol
Why may hypothyroid pt have delayed recovery/emergence?
hepatic metabolism and renal clearance of drugs may be slower and have prolonged effect
Why may response to inotropic drugs in hypothyroid pt be diminished?
the # of beta receptors is decreased
Myexedema coma may be precipitated by what?
surgery, usually in elderly pts
Myexedemia is more common in what pts and what are 3 symptoms?
elderly; hyponatremia, hypothermia, hypoventilation
Where are parathyroid glands located? And how many do most ppl have?
posterior surface of thyroid gland; 4 (some have 3 or 5)
What is the blood supply to the parathyroid glands?
inferior thyroid arteries
Parathyroid hormone is released from what in response to what?
chief cells in parathyroid gland in response to low serum ionized Ca
PTH is also released in response to what 2 electrolyte abnormalities?
hyperphosphatemia, acute hypomagnesemia
PTH does what to extracellular calcium and extracellular phosphate?
increases;decreases
What would be a fairly common cause of parathyroid gland hypertrophy?
lactation and pregnancy which cause a sustained deficit in ionized Ca and therefore result in hypertrophy
How does PTH increase Ca?
it acts on bone to mobilize Ca; osteoclasts stimulate rapid absorption of Ca from bone to ECF
What does increased ECF Ca do to PTH?
decreased PTH release stimulating deposition of Ca
3 ways in which PTH increases Ca?
increased decomposition of bone, releasing Ca, increased absorption of Ca from food by intestines, reabsorption of Ca from urine by kidneys
This hormone is secreted from the thyroid in response to elevated ionized Ca?
calcitonin
Which cells in the thyroid secrete calcitonin?
parafollicular/C cells
How does PTH increase renal absorption of Ca?
PTH promotes the formation of an active form of vit D when plasma Ca levels are low by secreting an enzyme in the kidneys which increases intestinal absorption of Ca and phosphate
Why does kidney disease or absence of PTH result in hyopcalcemia?
enzyme in kidneys is not formed and effect of vit D on Ca and phosphate regulation is lost
Parathyroid dysfunction affects what 3 areas of the body?
bone, intestinal tract (absorption of Ca), kidney (formation of vit D, reabsorption of Ca, and increased excretion of phosphate)
Hyperparathyroidism= ______calcemia
hyper
S/s hyperca?
HTN, ventricular dysrhythmias, shortened QTI, impaired renal concentrating ability, renal failure, polyuria, polydipsia, ileus, N/V, muscle weakness, osteoporosis, mental status changes
The enzyme vitamin D1 hydroxylase converts what to the active form 125 OH vit D? And at what level does this increase Ca absorption?
liver byproduct 25 hydroxy vit D; small intestine
Normal Ca levels?
8.8-10.4
90% of time parathyroidism is due to what?
adenoma
Hyperparathyroidism is where PTH levels are high in spite of?
high serum Ca
In hyperparathyroidism calcifications may be formed in which organs leading to dysfunction?
pancreas-pancreatitis, kidney- nephrolithiasis, polyuria, heart- bradyarythmias, BBB, heart block, stomach- peptic ulcer
What type of anesthesia can removal of PT gland be performed under?
general or cervical plexus block with MAC
Severe hypercalcemia (what value is that) is treated with what?
> 13-16; isotonic saline and loop diuretics
Some anesthetic considerations for pts with hyperparathyroidism?
renal status (failure, stones, polyuria), avoid hypoventilation bc hyperventilation blows Ca away, may be sensitive to NMB, arrythmias respond to Ca channel blockers, prone to PONV, careful with positioning
How does alkalosis lower Ca?
it shifts Ca to protein bound form and decreases serum levels of Ca
Why would one have hypoparathyroidism?
inadequate secretion of PTH or peripheral resistance to its effect
3 causes of hypoparathyroidism?
removal of PT tissue, radiation, chronic Mg deficiency (alcoholism)
Why do ppl with hypoparathyroidism experience muscle spasms and tetany?
threshold of excitable membranes is lowered
Post op parathyroidectomy- beware of what 2 things?
laryngospasm, resp distress d/t edema, bleeding, or bilat RLN damage
Treatment for post op parathyroidectomy?
Ca Cl IV slow
Is being unable to talk after a parathyroidectomy normal?
no-maybe bilat RLN damage and need to intubate
How does insulin lower blood sugar?
insulin binds to a receptor on the cell, which activates protein cascades, and translocation of GLUT 4 transporter to the plasma membrane brings in an influx of glucose, which then leads to glycolysis and fatty acid synthesis
What are islets of langerhans?
microscopic collections of cells scattered throughout the pancreas which produce hormones
How do the hormones produced by the islets of langerhans take effect?
they are directly secreted in to the capillary blood vessels rather than entering the ducts
What is the blood supply of the islet cells like?
abundant blood supply
What % of beta cell ftn is lost in Type I DM before hyperglycemia occurs?
80-90%
What is the short and sweet patho description of Type I DM?
glucose is presence in abundance but unable to reach the cells d/t lack of insulin
Pathophysiology of Type II diabetes?
impaired insulin secretion, peripheral insulance resistance, excessive hepatic glucose production d/t environmental, genetic, lifestyle factors
When blood glucose rises >?, glucose spills in to the urine?
180-200
When insulin is deficient what does the liver do?
liver increases its glucose output so intracellularly glucose is low but extracellularly glucose is high
Glucose starved cells use what for fuel?
fat and protein
The increased breakdown of triglycerides to free fatty acids and glycerol contributes to what (in diabetic pts)?
atherosclerotic and angiopathic changes
What becomes the main energy source in the diabetic pt?
fatty acids
Why are increased fatty acids bad in the diabetic pt?
fatty acids are converted to ketone bodies in the liver, H concentration increases, and the ketone body acetone is excreted by the lungs, resulting in acetone breath
What causes weight loss, weakness, and organ dysfunction in diabetic pt?
protein catabolism, free amino acids are converted in the liver into glucose
What does A1C mean?
structural tissue proteins and hemoglobin become glycosolyated, which contributes to organ damage
How much more likely is diabetic pt to have HTN than nondiabetic pt?
twice as likely
A diabetic pt with sudden hypotension- you should think?
silent MI
Risk of MI is __-__ times higher in diabetic that nondiabetic?
2-10
Risk of stroke is how much larger in diabetic versus nondiabetic?
twice
Risk of PVD is __ to ___ higher in diabetic versus nondiabetic?
5-10 x greater
Autonomic neuropathy leads to dysfunction of vagus nerve resulting in?
orthostatic hypotension, tachycardia, dysrthymias
Autonomic neuropathy does what to GI system?
risk for aspiration, slowed gastric emptying, reflux esophagitis
What happens to the diabetic pt’s response to atropine and propranolol?
reduced response d/t autonomic neuropathy
Some other complications of autonomic neuropathy?
lack of sweating, lack of hr variability, resting tachycardia, asymptomatic hypoglycemia
Are diabetics with gastroparesis mask candidates?
no
Why do you have to be careful with preop sedation and post op pain meds in diabetic pts?
impaired respiratory response to hypoxia
4 labs necessary to eval kidney ftn in diabetic pt?
UA, BUN, creat, lytes
Stiff joint syndrome is seen more with which type of diabetic pt?
Type I
Test for stiff joint syndrome?
+ prayer sign
What 2 parts of ortho system may be involved in stiff joint syndrome and make intubation difficult in diabetic pt?
TJ joint and C spine limited movement
A1C
7
Standard types of measurement of glucose before surgery?
venous plasma or serum
Why might chronic hyperglycemia leave the pt dry?
it’s associated w osmotic diuresis
What is a pt at risk for if they take metformin before surgery?
hypotension, renal hypoperfusion = lactic acidosis and accumulation in renal impairment, CHF, liver disease
Metformin should be held how long before surgery?
> 48 hours
What type of surgeries do you have to be cautious ab in pts with an insulin pump?
electrocautery and radiation
How much dose 1 unit of insulin lower blood glucose?
40-50 mg/dL
Beware of anaphylaxis with what drug in pts taking NPH or protamine zinc insulin?
protamine sulfate
What causes hyperglycemia intraoperatively?
activation of SNS, catecholamine, cortisol, and GH secretion
You can see LOC/seizures at blood glucose
50
Some causes of hypoglycemia?
beta blockers, severe liver disease, toxins (ethanol), gastric bypass surgery, sepsis, insulin secreting tumor
In a 70 kg pt, 15 mL of D50 raises the blood glucose concen by what?
30 mg/dL
1 mL of D50 raises blood glucose concen by how much?
2 mg/dL
DKA is usually in which type of diabetes?
I
DKA usually develops over how long?
24 hours
Triad for DKA?
hyperglycemia, acidosis, ketonemia
In DKA blood sugar is usually > than what?
250
6 precipitants of DKA?
critical illness, MI, trauma, CVA, burn, infection
S/s DKA?
volume depletion (5-8 L), tachycardia, met acidosis, lyte depletion (hypokalemia), N/V, abdominal pain, fruity odor to the breath (ketones from lack of insulin), Kussamaul respirations, coma
2 complications associated with DKA?
gangrene and ischemic lower extremity
Treatment for DKA?
isotonic fluids, K, insulin
Is mortality higher with DKA or HHS?
HHS
Why is HHS life threatening?
it’s a hyperglycemic state that leads to diuresis and severe dehydration
Glucose is usually > than what in HHS?
600
S/s HHS?
hyperglycemia, polyuria, polydipsia, hypovolemia, hypotension, tachycardia, organ hypoperfusion, acidosis, risk of thrombus, hyperosmolality, seizures, coma
Hypoosmolality > than mOsml induces dehydration of neurons?
360
What does severe hyperglycemia do to Na?
produces false hyponatremia
With each 100 mg/dL increase in blood sugar, plasma Na concentration lowers by?
1.6 mEq/L
In HHS if plasma osmolarity is >320, what fluid should be given and until when?
large volumes 1000-1500 mL/h of 1/2 NS until osmolarity
What are some hazards to rehydrating in elderly?
rehydrate slowly because they are prone to cerebral edema and CHF
Difference in the pH of DKA vs HHS?
pH 7.3 in HHS
Difference in serum osmolarity between DKA and HHS?
serum osmolarity is greater in HHS
Difference in mental obtundation in DKA vs HHS?
mental obtundation is present in HHS but variable in DKA
Difference in serum K with DKA vs HHS?
normal or slight increase in DKA; normal or lower in HHS
Function of adrenal glands?
synthesize and store essential hormones
Outer and inner part of adrenal gland?
outer= cortex; inner= medulla
3 hormones secreted by adrenal cortex?
mineralcorticoids (aldosterone); glucocorticoids (cortisol); androgens (dehydroepiandrosterone)
Hormone secreted by adrenal cortex which maintains and regulates immune and circulatory function and effects carbo, protein, and fatty acid metabolism?
glucocorticoids/cortisol
This adrenal cortex hormone regulates ECF volume and K thru reabsorption of Na and secretion of K?
mineralcorticoids (aldosterone)
4 times which produce an increase in aldosterone?
surgery, CHF, hypotension, hypovolemia
4 things which stimulate release of aldosterone?
angiotensin II, ACTH, pituitary hormones, hyperkalemia
What stimulates synthesis of cortisol?
ACTH
These hormones enhance gluconeogenesis and inhibit peripheral glucose utilization?
glucocorticoids/cortisol
Inner part of adrenal gland and the hormones it secretes?
adrenal medulla; norepi, epi, dopamine
This catecholamine constitutes 80% of adrenal catecholamine output?
epi
Because glucocorticoids are structurally related to aldosterone, they promote what?
Na retention and K excretion
This hormone is responsible for vascular and smooth muscle response to catecholamines?
glucorticoids/cortisol
Mechanism for regulating cortisol secretion?
ACTH, CRF
Most potent regulator of ACTH?
cortisol
4 things cortisol does?
gluconeogenesis, protein mobilization, fat mobilization, stabilizes lysosomes
Cortisol had direct - feedback effect on what and inhibits release of what? then, the anterior pituitary decreases release of?
hypothalamus; CRH and CRF; ACTH
Secretion of what 3 things follow circadian rhythms?
ACTH, cortisol, and CRH
Daily production of cortisol is usually?
15-30 mg
Increased aldosterone production, which is a dysfunction of the adrenal cortex, results in?
excess mineralocorticoid
2 types of increased aldosterone production-primary and 2ndary- are caused by what?
primary: (Conn syndrome), from adrenal adenoma independent of stimulus; 2ndary: increased renin production
3 s/s of increased aldosterone and treatment for it is?
HTN, ECF volume weakness; surgical removal of tumor-lap adrenalectomy
Increased aldosterone causes what for the Na/K pump?
Increased Na/K exchange so a decrease in K and retention of Na
A good drug to manage HTN for hyperaldosteronism?
Spironolactone (aldosterone antagonist)
You should avoid what w the vent in a hyperaldosteronism pt?
hyperventilation bc it will lower the K further
Why do you have to be careful with NMB in hyperaldosteronism pts?
hypokalemia may enhance the MR
Overproduction of cortisol is what disease?
Cushing’s
Causes of Cushing’s?
anterior pituitary or adrenal tumors
Most common cause of Cushing’s?
exogenous administration of corticosteroids
S/s Cushing’s?
central obesity with thin extremities, HTN, moon face, striae, thin, atrophic skin, muscle weakness, increased intravascular fluid volume, hypokalemia, fatiguability
Anesthetic management for pt with Cushing’s?
lytes, Spironolactone, careful w positioning, conservate MR if muscle weakness present, increased risk of infection, thromboemboli are more common, need supplemental steroids
Why are thromboemboli more common in Cushing’s pt?
HTN, obesity, increased Factor VIII, high hct
Addison’s disease is deficiency in what 3 hormones?
adrenal androgens, glucocorticoids, mineralcorticoids
2 causes of Addison’s disease?
TB, autoimmune diseases
Primary cause of Addison’s? And what are some causes of that?
destruction of adrenal gland; congenital, infection, malignancy, trauma, HIV, adrenal hemorrhage
2ndary cause of Addison’s?
decrease in ACTH
Tertiary cause of Addison’s?
d/t exogenous admin of glucocorticoids and cortisone admin
S/s Addison’s?
(cortisol def): fatigue, weakness, weight loss, abdominal pain, diarrhea, hypoglycemia; aldosterone def: volume depletion-orthostatic hypotension, hyponatremia, hyperkalemia, hyperpigmentation
Treatment of Addison’s?
100 mg Hydrocortisone or Prednisone
Which anesthetic drug can cause adrenal insufficiency and should avoided in those pts prone to adrenal insufficiency?
etomidate
Benefits of steroid therapy are weighed down by some risks such as?
glucose intolerance, stress ulcers, impaired wound healing, immunosuppression
What is acute adrenal crisis?
sudden onset of severe adrenal insufficiency
How does acute adrenal crisis progress and what can cause it?
very rapidly and is life threatening; stress
Main sign of acute adrenal crisis?
HD instability
Have high suspicion of acute adrenal crisis if?
hx of autoimmune, exogenous steroid use, HD instability, hyperpigmentation
Pheo is a catecholamine secreting tumor which consists of cells originating from?
embryonic neural crest (chromaffin tissue)
Are pheos usually malignant and in both adrenal glands?
usually benign and in one adrenal gland
4 s/s of pheo?
paroxysmal headache, sweating, HTN, palpitations
First indication of pheo can be?
intraop HTN and tachycardia
A pheo diagnosis is made w what and a false + can be caused by what?
urine metaneprhine level; coffee, tricyclics, phenoxybenzamines; another diagnostic test is a suppression test- clonidine will suppress catecholamines that are neurogenically controlled, but will not suppress catecholamines from pheo
Should you give an alpha or beta blocker first in pheo pt?
alpha bc beta may cause dilation in skeletal muscles and worsen HTN
Alpha blocker and dose for pheo?
Phenoxybenzamine 10 mg BID, increasing q 2-3 days by 10-20 mg for a max dose of 1mg/kg
Beta blocker helps control what in pheo pt?
reflex tachycardia
When is beta blocker added in pheo pt?
several days after initiation of alpha blocker; to avoid the possibility of unopposed alpha constriction resulting in severe HTN and ischemia
5 preop treatment endpoints for pheo pt?
1) BP 24 hours; 2) presence of orthostatic hypotension (not
3 beta blockers good for pheo?
propranolol (20-80); atenolol (12.5-25); metoprolol (25-50)
Avoid what 5 drugs/actions in pheo pt intraop?
ephedrine, ketamine, hypoventilation (SNS stimulation); atracurium, MS (histamine)
6 good drugs to give in pheo pt?
alpha blockers, beta blockers, MgSO4, nicardipine, nitroprusside and nitroglycerin
Post of HTN in pheo pt may indicate?
another tumor
Treatment for post op hypotension in pheo pt?
fluids are initial therapy, phenyl pushes and gtt, Norepi gtt
One reason why hypotension is common in post op pheo pt- what type of blockade is persistent?
alpha blockade
What is MEN?
overactivity of 2+ endocrine glands
MEN 1 disorders and bold the most common occurring tumor?
pituitary adenoma, PARATHYROID HYPERPLASIA, pancreatic tumors
MEN 2 a tumors and bold most common?
MEDULLARY THYROID CANCERS, pheo, PT tumors
MEN 2b and bold most common?
medullary thyroid, pheo, MUCOSAL NEUROMAS, marfanoid body habitus
What is carcinoid syndrome?
slow growing tumors which cause secretion of vasoactive substances and can be life threatening
Some of the vasoactive substances secreted by carcinoid syndrome?
serotonin (vasoconstriction), histamine (vasodilation), kallikrein (vasodilation)
Cells which secrete vasoactive substances in carcinoid syndrome?
enterochromaffin cells
Most carcinoid syndrome tumors are where in the body?
GI tract; metabolic products are released into the portal circulation and destroyed by the liver before causing systemic effects- little sx
4 other places carcinoid tumors may develop?
lung, pancreas, thymus, liver
What is the life threatening form of carcinoid syndrome and what precipitates it?
carcinoid crisis; physical manipulation of tumor
What are some other times carcinoid crisis can occur?
induction of anesthesia, mets of tumor to liver and shuts down liver
Classic sign of carcinoid syndrome and caused by?
cutaneous flushing; kallikrein
What substance causes right sided HF in carcinoid syndrome? What ab dramatic BP swings? And bronchospasm? And profuse diarrhea and abdominal pain?
serotonin; kallikrein and histamine; kallikrein and histamine; serotonin
Some other s/s carcinoid syndrome?
cyanosis, N/V, hepatomegaly, RP and pelvic fibrosis, cough, wheezing, dyspnea, pulmonic and tricuspid valve thickening and stenosis, endocardial fibrosis
Diagnosis of carcinoid syndrome?
serotonin metabolites in the urine or elevated plasma levels of chromogranin A
Pretreatment for surgical removal of carcinoid tumor consists of?
hypotension that may be caused by manipulation of tumor; H1 and H2 blockers (benadryl and zantac)
How soon before surgery in carcinoid tumor pt should you start ocreotide?
2 weeks
2 diagnostic tests before carcinoid tumor surgery?
x ray to eval extraintestinal manifestations, Echo to diagnose right sided heart disease
2 examples of serotonin antagonists are?
ocreotide and somatostatin
What’s the 1/2 life and dose of ocreotide?
100 min; 100 mg SQ 2-3 times daily
How does Sandostatin/ocreotide work?
inhibits all bioactive substances
1/2 life of somatostatin?
2-3 min
Type of medication for carcinoid syndrome which is an inhibitory peptide to antagonize and suppress the release of tumor products?
stomatostatin
How does somatostatin work?
it binds to receptors of tumor cells and results in decreased secretion
Be ready to treat what 4 things during surgery for pt with carcinoid syndrome?
decreased peripheral vascular resistance, hypotension, bronchospasm, HTN
What pressor should you use for refractory hypotension in pt with carcinoid syndrome?
vasopressin
Avoid histamine releasing substances such as what 3 meds during carcinoid syndrome surgery?
morphine, cisatracurium, suxxs
3 meds that are good to give during carcinoid syndrome surgery?
steroids, H2 blockers, ocreotide
Is spinal anesthetic ok for carcinoid syndrome surgery?
yes
