Endocrine/Allergy Flashcards
Corticosteroid supplementation recommendation
Who is on > 10 mg/day or previously taking > 10 mg/day and their last dose < 3 months prior to surgery.
Minor surgery: 25 mg hydrocortisone at induction
Moderate surgery: daily dose + 25 mg at induction + 100mg/day infusion for 24 hrs
Major surgery: daily dose + 25 mg at induction + 100 mg/day infusion for 2-3 days
Who is on high dose corticosteroid for immunosuppressantion -> no additional dose as this is already supraphysiologic dose.
Hormones decreases its secretion during stress response
T3/T4
GRH
Insulin (due to inhibition of pancreatic B cells through alpha adrenergic receptors secondary to + SNS).
GH (increases initially then followed by decline on POD 1).
Hyperglycemia perioperative associated with increase risk of …
Immunosuppressant Infections Osmotic diuresis Delayed wound healing Delayed gastric emptying Sympatho-adrenergic stimulation Increased mortality Reduces skin graft success Exacerbating brain, spinal cord, and renal damage by ischemia Worsen neurological outcome in TBI Postop cognitive dysfunction post CABG
Drugs and their glucocorticoid (GC) vs mineralocorticoid (MC) potency?
GC. MC
Hydrocortisone 1. 1
Cortisone. 0.8. 0.8
Prednisone. 4. 4
Methyl. 5. 0
Dexa. 25 0
Fludro. 10. 125
Who is at increased incidence of latex allergy?
Health care workers, atopic individuals, and those with allergies to certain foods (avocados, bananas, chestnuts, kiwi fruit, papayas, potatoes, tomatoes)
Hormones that alter plasma potassium levels?
Aldosterone and cortisol promote renal potassium secretion leading to losses through the urine.
Insulin and thyroid hormones enhance cellular potassium uptake.
Glucagon effects?
Glucagon raises blood glucose levels by stimulating glycogenolysis and gluconeogenesis. it also stimulates lipolysis and impairs glycolysis which results in increased availability of substrates for gluconeogenesis.
Glucagon also has cardiac inotropic and chronotropic effects. Similar to catecholamines, it enhances activation of adenyl cyclase in cardiac myocytes, but its effects are NOT blocked by β-blockers. The typical dose is 1-5 mg IV followed by an infusion.
Other effects of glucagon include, but are not limited to:
- Decreased gastric motility
- Relaxation of smooth muscle
- Decreases biliary sphincter and lower esophageal sphincter tone
- Mild generalized vasodilation
- Dilates hepatic arterioles and increases hepatic and splanchnic blood volume
- Antagonizes vasoconstrictor effects of catecholamines
- Enhanced urinary excretion of inorganic electrolytes
Primary hyperthyroidism is characterized by …
elevated T3, T4 (free and total), and thyroid hormone binding ratio, and a low or normal TSH.
Should NMB dose increase or decrease in hypercalcemia state?
Hypercalcemia antagonizes the effects of non-depolarizing neuromuscular blockers and higher doses may be required to obtain the desired effect.
Ca dose as intrope?
Calcium is an amazing inotrope particularly in the setting of hypocalcemia. An IV bolus dose of 7 mg/kg may last as long as 10-15 minutes. It is especially useful when separating from cardiopulmonary bypass (CPB). Calcium can reverse hypotension due to hyperkalemia secondary to cardioplegia as well as correct the dilutional hypocalcemic effect of CPB.
Anaphylactic vs anaphylactoid reactions? Common intraoperative triggers of each?
Anaphylactic and anaphylactoid reactions are both histamine-mediated reactions with signs and symptoms that are clinically indistinguishable.
Anaphylactic reaction is a type I hypersensitivity reaction, an IgE mediated allergic response, causing mast cell degranulation and histamine release.
Anaphylactoid reactions are drug reactions that cause uncontrolled histamine release by a mechanism not involving IgE.
They cant be distinguished clinically as both rxn produce the same; urticaria, bronchospasm, angioedema, and venodilation causing hypotension and cutaneous flushing.
Common intraoperative triggers of anaphylactic reactions include muscle relaxants, latex, and antibiotics.
Common triggers for anaphylactoid reactions include protamine, IV contrast dye, opioids, d-tubocurarine, and thiopental.
