Endocrine- Corticosteroids Flashcards
What are the Natural and Synthetic steroids?
Natural –Cortisol (hydrocortisone), cortisone, aldosterone Synthetic –Prednisone, Prednisolone, Methylprednisone, Dexamethasone
Effects of Mineralcorticoids
Aldosterone –Reabsorption of Na and excretion of K in the distal tubule
Effects of Glucocorticoids
- Anti-inflammatory effects
- Augmentation of sustained SNS activity during periods of emotional and physical stress
Where are mineralcorticoid and glucocorticoid receptors found?
Mineralcorticoid– Organs of excretion –Colon, salivary glands, kidney, sweat glands, hippocampus
Corticosteroids -Wide Spread
MOA of corticosteroids
- Enter cells and bind to steroid receptors in cytoplasm 2. This complex moves into the nucleus 3. It influences DNA transcription and protien synthesis
MOA of steroids, Metabolic effects (and long term effects)
- Increase blood glucose (can cause Diabetes) 2. Break down Proteins (muscle wasting) 3. Increase Triglycerides (Maldistribution, athrosclerosis)
MOA of steroids, Inflammation
- Phospholipase A2 (produces Arachidonic acid) is inhibited by a steroid generated protein = less arachidonic acid 2. Cytokine and chemokine release decreased OVERALL -Increase in anti-inflammatory protein transcription -Decreased in pro-inflammatory protein transcription
How much endogenous cortisol do we produce daily?
10-20 mg/ day on average 50-150 mg/ day during the week before orals (or other stressors)
Cortisol pharmakokinetics (the prototype in this class) (PB, formulations, metabolism, e1/2
- Many Routes -IV formulation Solu-cortef -90 PB -70% metabolized in liver -30% unchanged in urine -e1/2 1.5-3.0 hours (clinical effects last for much longer)
Relative potencies for Anti-inflammatory and Sodium retaining potency between meds (Chart)
Maggie!!!!!! insert this chart here slide 27
Highlights of Synthetic Corticosteroids
- Methylprednisone IV- intense glucocorticoid effects
- Betamethasone PO/IV- lacks mineralcorticoid effects
- Dexamethasone PO/IV- used for cerebral edema, antiemetic, and airway edema, no mineralcorticoid effects
- Triamcinolone (intraarticularly, IV/PO)- often used for epidural injectiosn
- Prednisolone PO/IV- mineral and gluco effects —–Prednisone is converted to prednisolone in body
Reasons to Give Steroids
Replacement for deficient adrenal or pituitary, Anti-inflammatory
When should you give a stress dose of steroids?
If they have taken a steroid for 1 month in the last 6-12 months, Give it! You can always draw it up and have it ready but more than likely you’ll give it
Example of dosing in acute and chronic adrenal insufficiency
Acute- Cortisol 100 mg q8 hrs Chronic- PO 25 mg q am and 12.5 mg in afternoon
Asthma Uses Acute and Chronic
- Acute
- <1hr see Beta agonist enhancement
- 4-6 hrs anti-inflammatory effects
- Chronic
- 1st line therapy for bronchospasm in asthmatics
- 80-90% swallowed and at risk for dysphonia
- Usually do not see HPA axis disterbance until daily doses >1500 mcg adults, >400 mcg peds
Steroids as an Antiemetic
Decadron - 8-10mg IV - Must be given shortly after induction for best effects -synergistic with zofran -e1/2 3 hrs —antiemetic effects last for up to 24 hrs
Other uses of Steroids
-Intracranial Tumors- ICP and edema control -Immunosuppression- Transplants and autoimmune -Lumbar disk herniation- epidural injections –Triamcinolone 25-50 mg –or 40-80 mg methyprednisolone with lido –HPA axis suppressed 1-3 months after
Side Effects
- HPA axis suppression - CV COLLAPSE INTRA-OP 2. FLuid and electrolyte imbalances 3. Osteoporosis 4. Infectiosn 5. PUD 6. Skelatal Muscle Weakness 7. Psych disorders 8. Growth retardation in children 9. decrease anticoagulant effectiveness
Do you want to give decadron while pt is awake?
Nope, Fire crotch
how large of a stress dose should you give? (chart)
