Corticosteroids Flashcards
What is the role of the hypothalamus?
It produces hormones including the Corticotropin releasing hormone
Maintains homeostasis through regulating body temperature, controlling appetite, managing sexual behavior, managing emotional responses
What hormones are released from the posterior pituitary?
Oxytocin & ADH (antidiuretic hormone)
What hormones are released from the anterior pituitary?
Leutinizing hormone, Folicular stimulating hormone, growth hormone, adrenocorticotropic hormone, thyroid stimulating hormone, prolactin
Where is cortisol released from?
zona fasiculata in the adrenal cortex
Where is aldosterone released from?
zona glomerulosa in the adrenal cortex
What is released from the adrenal medulla?
epinephrine and norepinephrine
The zona reticularis releases
sex hormones
What is the role of cortisol (hydrocortisone)?
Increases carbohydrate & protein metabolism
suppress immune system
suppression of pro-inflammatory cytokines
mobilization of free fatty acids
inhibits insulin from shuttling into cells
When does cortisol peak?
8 am
When is cortisol at its lowest concentration?
midnight
What is the normal production of cortisol?
15-30 mg/day
What causes release of cortisol?
ACTH
What are cortisol levels in response to minor procedures?
up to 50 mg/day
return to baseline within 24 hours
ex. hernia repair
What are cortisol levels in response to moderate procedures?
up to 75-100 mg/day
return to baseline by 5 days
ex. colectomy
What are cortisol levels in response to major procedures?
up to 200 mg/day
usually returns to baseline by 5 days
ex. major trauma
What is Cushing’s Sydnrome?
Too much cortisol typically due to increase of corticosteroids
What are reasons Cushing’s disease can occur?
Tumor on pituitary gland resulting in increased release of cortisol
What are the signs and symptoms of Cushing’s Disease?
moon face, hunch back, thin skin, osteoporosis, amennorhea, Na & fluid and retention, males develop breasts
When do we see clinical manifestations of Addison’s Disease?
When 90% of cortical zones are destroyed
What is the most common cause of Addison’s disease?
autoimmune destruction
What are reasons for secondary adrenal insufficiency?
problems w/ hypothalamus or anterior pituitary
TBI
Chronic glucocorticoid treatment (3-4 weeks)
Topical administration such as aersols for asthma and COPD or creams used for skin problems
Ischemic/hemorrhagic lessons of hypothalamic-pituitary axis
What is an adrenal crisis?
It is a life threatening acute deterioration and includes at least two of the following:
hypotension (treating BP that is not going back up), acute abdominal symptoms, N/V, AMS, fatigue, fever, laboratory abnormalities
What are the abnormalities found in adrenal crisis?
hyponatremia, hyperkalemia, hypoglycemia, rarely hypercalcemia
What are the causes of adrenal crisis?
interruption of gluccorticoid intake, infections, surgery, gastroenteritis, stress
How do you manage adrenal crisis?
give them fluid (0.9 NS 1-3 L over 6-12 hours)
want to give hydrocortisone (initial 100 mg)
Patients who have surgery at X time have a quicker return to baseline cortisol levels
afternoon
What is the mechanism of action of corticosteroids?
stimulates change in transcription of 456 DNA -synthesis of proteins
Target cells contain enzyme- 11-beta hydroxysteroid dehydrogenase (think etomidate) turns cortisol (active) into cortisone (inert)
What is the classification of corticosteroids?
1) reabsorption of Na+ in exchange for K+ in renal distal tubules (mineralcorticoid effect)
2) anti-inflammatory properties (glucocorticoid effect)
Synthetic corticoids are all
glucocorticoids
This interferes with the oral absorption of corticosteroids
antaccids
The elimination half-time of cortisol is
1.5-3 hours
How is cortisol eliminated?
phase II liver- 70% conjugated in liver
Cortisol readily
cross the placenta
Cortisol is
highly protein bound to corticosteroid-binding globulin
What are the clinical uses of corticosteroids?
antiemetic, analgesia, immunosuppression, laryngeal edema, can prolong regional blocks, asthma, cerebral edema, adrenal insufficiency
Comment on corticosteroids and covid 19
beneficial for patients who are severely ill and requiring ventilation or oxygen supplementation
Research has shown that use of corticosteroids does not cause
does not contribute to wound complications or wound healing or hyperglycemic events
What can be used safely for PONV prophylaxis?
4-8 mg dose of dexamethasone
What dosage of dexamethasone can be given for postop sore throat?
Prophylactic >0.2 mg/kg
What are the perioperative adrenal supplementation guidelines for hydrocortisone?
superficial (dental biopsy)- 0
Minor (colonoscopy, hernia repair)- 25 mg IV
Moderate (colon resection, joint replacement)- 50-75 mg IV, taper over 1-2 days
Major (CV, Thoracic)- 100-150 mg IV taper over 1-2 days
When should we give perioperative steroids?
- pharmacologic doses of glucocorticoids greater than 5 mg of prednisone equivalent/day
- The period of treatment with corticosteroids was for 2-3 weeks or longer
- The treatment occurred during the immediate 12 months before surgery
Acute side effects of corticosteroids include
hyperglycemia
Chronic side effects of corticosteroids include:
HPA axis suppression, corticosteroid supplementation, electrolyte and metabolic changes, CNS dysfunction, peptic ulcer disease, skeletal muscle myopathy
Drugs that cause enzyme inhibition with corticosteroids
ketoconazole, fluconazole, etomidate, metapyrone
Drugs that accelerate metabolism with corticosteroids
phenytoin (dilantin), rifampin, phenobarbital, ephedrine
Hydrocortisone is also know as
cortisol and is short acting
What are the corticosteroids predominantly used in practice:
hydrocortisone, prednisone, prednisolone, methylprednisolone, dexamethasone
What corticosteroid is used to produce an intense glucocorticoid affect?
methylprednisolone
What corticosteroids rely most on liver function?
prednisolone and prednisone
What corticosteroid is the sole replacement therapy for adrenocortical insufficiency?
prednisolone
Aldosterone is known for its’
sodium retaining potency; it is a mineralcorticoid
What is the duration of action of cortisol?
8-12 hours so we need to give more than one dosage
Prednisone can only be given
PO
