ITE CA2 Endocrine/Metab/Renal/Electrolytes Flashcards
Effect of corticosteroids on: WBC, hemoglobin, blood glucose, K, Na, acid/base status, urinary uric acid, urinary calcium.
Corticosteroids are associated with leukocytosis, increased hemoglobin, hyperglycemia, hypokalemia, mild hypernatremia, alkalosis, increased urinary uric acid, and increased urinary calcium.
FENA cutoff for pre-renal
Fractional excretion of sodium is a useful tool in helping to distinguish the cause of acute kidney injury. In general, a FENA < 1% indicates a prerenal cause such as hypovolemia. Greater than 1% points toward ATN or another intrinsic cause.
prerenal urine osmolality
greater than 500
prerenal urine sodium
less than 10
BUN:Cr ratio
prerenal greater than 20
intrinsic/ATN less than 15
postrenal greater than 15
FENa cutoffs
prerenal <1
intrinsic >2
postrenal >2
random urine sodium cutoffs
prerenal <20
intrinsic >20
postrenal >40
Hypothermia, AMS, non-pitting edema
Myxedema coma is an extreme form of hypothyroidism that is classically characterized by altered mental status, hypothermia, and non-pitting edema. It is most commonly seen in patients with chronic hypothyroidism in the setting of a physiologic stressor such as infection and is considered a life threatening emergency.
TrueLearn Insight : Myxedema coma is rare, and most commonly presents to anesthesiologists in the postoperative period after a trigger such as infection, exposure to cold temperatures, and excessive sedation and analgesic medications.
Table 3: Summary of PTH, Calcium, and Phosphorus Disorders
DISORDER - INTACT PTH - CALCIUM - PHOSPHORUS
pHPTH
FHH
2? HPTH
Malignancy
Hypo-PTH
(pHPTH = primary hyperparathyroidism, FHH = familial hypocalciuric hypercalcemia, 2? HPTH = secondary hyperparathyroidism, Hypo-PTH = hypoparathyroidism, PTH = parathyroid hormone)
Table 3: Summary of PTH, Calcium, and Phosphorus Disorders
DISORDER INTACT PTH CALCIUM PHOSPHORUS
pHPTH increased increased decreased
FHH normal-mild increase increased normal-mild decrease
2? HPTH increased decreased varies
Malignancy decreased increased normal
Hypo-PTH decreased decreased increased
(pHPTH = primary hyperparathyroidism, FHH = familial hypocalciuric hypercalcemia, 2? HPTH = secondary hyperparathyroidism, Hypo-PTH = hypoparathyroidism, PTH = parathyroid hormone)
Carcinoid syndrome causes the classic triad of______. Diagnostic testing includes measuring _____
Carcinoid syndrome causes the classic triad of flushing, asthma, and right-sided heart disease. Diagnostic testing includes measuring urine 5-hydroxyindoleacetic acid
Lung metabolism of serotonin evidently prevents involvement of the left side of the heart with carcinoid syndrome.
Best test to eval hepatic sythesis
Prothrombin time (PT) is the most useful to diagnose hepatic synthesis abnormalities because many of the procoagulants in this test are synthesized in the liver. They also have shorter half-lives thus alterations in synthesis are observed faster than with other tests, such as albumin.
Factors not produced in the liver
III, IV, VIII
Where is factor VIII produced
endothelial cells and bone marrow
Growth hormone
Growth hormone is an anabolic hormone; most of its effects are mediated by IGF-1. It causes hyperglycemia and insulin resistance, as seen in patients with acromegaly.
where is angiotensin I converted to II
pulmonary circulation by ACE
Where is renin produced
juxtaglomerular apparatus in kidney
what does renin do
cleaves angiotensinogen into angiotensin I
Norepinephrine site of degradation and inactivation
pulmonary endothelium and nerve terminals
Acromegaly lung volumes
Patients with excess growth hormone (GH) actually have increased lung volumes, which causes subsequent ventilation-to-perfusion mismatching.
Resultant manifestations of a GH-secreting pituitary tumor include mass effect side effects (headache, visual field defects, rhinorrhea) and excess growth hormone side effects (skeletal overgrowth such as prognathism, soft-tissue overgrowth, connective tissue overgrowth causing possible recurrent laryngeal nerve paralysis and/or hoarseness, peripheral neuropathy (e.g. carpal tunnel syndrome,), visceromegaly, glucose intolerance, osteoarthritis, osteoporosis, hyperhidrosis, skeletal muscle weakness, increased lung volumes).
Lab findings in SIADH
1) Urine osmolality >100 mOsm, and often > 200-300 mOsm
2) Fractional excretion of sodium (FENa) > 1%
3) Urine Na+ > 20 mEq/L
4) Low serum uric acid and BUN
5) Dilutional, euvolemic hyponatremia (serum Na+ < 135 mEq/L)
what do glucocorticoids do
Glucocorticoids act to produce more aldosterone and inhibit the phospholipase A2 enzyme (PLA2). The PLA2 enzyme converts phosphatidylcholine to arachidonic acid, a precursor to prostaglandins, leukotrienes, and other proinflammatory mediators (e.g. TNF-α, interleukin-1, interleukin-6, cellular adhesion molecules).
Symptoms of Cushing syndrome
Cushing syndrome is characterized by a group of signs and symptoms resulting from prolonged exposure to excess cortisol. Classic symptoms include moon facies, buffalo hump, abdominal weight gain, thinning of the extremities, hirsutism, elevated blood sugar, and mood changes.
Protein synthesis and breakdown become mismatched and the resulting progressive protein loss causes drastic perturbations of body mass composition.
Classic physical signs of EXCESS protein breakdown that characterize Cushing syndrome are increased fatty deposits in the face (moon facies), shoulders, and neck (buffalo hump), truncal obesity, and muscle wasting (thinning) of the upper and lower extremities.
anesthetic considerations for Cushing
Anesthetic management of patients with Cushing Syndrome focuses on blood pressure regulation (these patients are typically hypertensive), glucose control, balancing electrolytes (often hypokalemia), and positioning (due to osteopenia).
Primary hyperthyroidism is characterized by
Primary hyperthyroidism is characterized by elevated T3, T4 (free and total), and thyroid hormone binding ratio, and a low or normal TSH
Primary hyperthyroidism vs Secondary hyperthyroidism
Primary hyperthyroidism is the term used when the pathology is within the thyroid gland. Secondary hyperthyroidism is the term used when the thyroid gland is stimulated by excessive thyroid-stimulating hormone (TSH) in the circulation.
Aldosterone effect on potassium
Aldosterone and cortisol promote renal potassium secretion leading to losses through the urine. Insulin and thyroid hormones enhance cellular potassium uptake.
Cortisol effect on potassium
Aldosterone and cortisol promote renal potassium secretion leading to losses through the urine. Insulin and thyroid hormones enhance cellular potassium uptake.
Insulin effect on potassium
Aldosterone and cortisol promote renal potassium secretion leading to losses through the urine. Insulin and thyroid hormones enhance cellular potassium uptake.
Thyroid hormones effect on potassium
Aldosterone and cortisol promote renal potassium secretion leading to losses through the urine. Insulin and thyroid hormones enhance cellular potassium uptake.
indications for emergent dialysis
AEIOU: Acidosis (uncompensated metabolic acidosis with pH below 7.1), Electrolytes, Ingestions (toxins), Overload, Uremia.
Perioperative hyperglycemia has been associated with
Perioperative hyperglycemia has been associated with immunosuppression, increased infections, osmotic diuresis, delayed wound healing, delayed gastric emptying, sympatho-adrenergic stimulation, and increased mortality.
In addition, it reduces skin graft success, exacerbates brain, spinal cord, and renal damage by ischemia, worsens neurologic outcomes in traumatic head injuries, and is associated with postoperative cognitive dysfunction following CABG.
pre-op pheo meds
Preoperatively, patients are commonly treated with phenoxybenzamine, which is a long-acting non-selective α-blocker. Selective α1-blockers, such as doxazosin, terazosin, and prazosin, are also commonly used.
Angiotensin II causes ___
Angiotensin II results in increased inotropy, chronotropy, catecholamine release, catecholamine sensitivity, aldosterone levels, vasopressin levels, and cardiac remodeling through AT1 receptors.
ACE inhibitors and ARBs help to prevent the remodeling that occurs secondary to angiotensin II and are beneficial in congestive heart failure.
substances commonly removed from patient’s blood in dialysis
Substances that are commonly removed from the patient’s blood include calcium, creatinine, magnesium, phosphate, potassium, urea, and free water.
substances may be added or removed from blood by dialysis
Substances that may be added to, or removed from, the patient’s blood include bicarbonate, chloride, glucose, and sodium.
dialysis effect on albumin or prealbumin
Serum concentrations of larger molecules such as proteins are usually (transiently) increased following HD due to a concentrating effect from the removal of free water. The absolute amount of these substances in blood stays approximately the same.
Metabolic Changes Associated With TPN:
Metabolic Changes Associated With TPN:
- Hypophosphatemia
- Hyperglycemia
- Hypercarbia
- Hypokalemia
- Hypomagnesemia
- Hyperinsulinemia
respiratory quotient
respiratory quotient of 0.7 would be pure lipid oxidation and a quotient of 1.0 would be pure carbohydrate oxidation.
Acute respiratory acidosis compensation
An acute respiratory acidosis is compensated with an increase in HCO3- of 0.2 mmol/L for each 1 mm Hg increase in PaCO2 above 40 mm Hg
Chronic respiratory acidosis compensation
A chronic respiratory acidosis is compensated with an increase in HCO3- of 0.4 mmol/L for each 1 mm Hg increase in PaCO2 above 40 mm Hg.
Type 1 hepatorenal syndrome
Type I HRS is an acute and rapid renal failure (doubling of serum creatinine) associated with a precipitating cause (e.g. spontaneous bacterial peritonitis, sepsis, surgery), that responds to medical therapy and stabilizes even after medical therapy is discontinued. Without treatment, the median survival is 2-4 weeks for type I HRS.
Type 2 hepatorenal syndrome
Type II HRS is an insidious onset of renal failure as a result of portal hypertension. Loss of intravascular volume from splanchnic dilation and ascites formation is compensated for with increased renal vasoconstriction and activation of the sympathetic, renin-angiotensin, and vasopressin systems
Propylthiouracil (PTU) and methimazole (MTZ)
Propylthiouracil (PTU) and methimazole (MTZ) are both medications that can be used to inhibit the production of thyroid hormone (T4).
In addition, propylthiouracil blocks the peripheral conversion of T4 to T3 - this makes PTU favorable over MTZ
thyroid storm treatment
Thyroid hormone release can be blocked by sodium or potassium iodide administration, however only after a thyrostatic medication such as propylthiouracil has been given. plus supportive treatment
A 56-year-old female is being monitored in the intensive care unit after presenting with a subarachnoid hemorrhage. On post-bleed day 2, the patient is noted to have new onset hyponatremia. On exam the patient appears euvolemic. Further workup reveals a high urine sodium and high urine osmolarity. Which of the following is MOST likely?
SIADH
Hyponatremia with euvolemia or hypervolemia is most likely syndrome of inappropriate antidiuretic hormone secretion (SIADH) in this patient
cerebral salt wasting volume status
hypovolemic
EKG changes hypocalcemia
shortened PR
prolonged QT*** classic
T wave inversion
EKG changes hypokalemia
PR prolonged QRS narrowed QT prolonged T waves flat U waves
