Steroids Flashcards
What’s primary adrenal insufficiency? secondary?
Primary= due to disease of the adrenal gland, secondary= due to deficient ACTH secretion by the pituitary gland or deficient CRH secretion by the hypothalamus
Should usual steroid treatment continue while stress dosing for surgery or illness is applied?
Yes, of course, because additional steroid replacement is to compensate for the additional stressor above baseline
What is the most common cause of adrenal insufficiency anaesthetists encounter?
Prescribed glucocorticoid therapy (pred >=5mg/day for 4 weeks or hydrocortisone-equivalent dose of 10mg/m2 per day) across all routes of administration. These doses can cause HPA axis suppression.
If in doubt of the necessity to give glucocorticoids, what should we do?
Give, as no long-term adverse consequences of short-term glucocorticoid administration
What’s the approach to taking Hx of pts with long-standing Dx of adrenal insufficiency?
They’ll often be well-informed about their disease, enquire about prev episodes of adrenal crisis, what’s their practice in medication adjustment for illness/injury/postop recovery?
Do they have a medic alert or steroid emergency card? their family should know “sick day rules”, pt may have hydrocortisone self-administration kits (eg. in case of vomiting).
Collaborate with the pts endocrinologist.
What’s the regimen for management of pts w primary or secondary adrenal insufficiency undergoing GA or regional, as recommended by the AAGBI? How does this differ if the pt has adrenal suppression purely due to receiving adrenosuppressive doses of steroids (aka tertiary, >=5mg pred equivalent for 4/52 or longer)?
100mg IV hydrocortisone @ induction of Anaesthesia, followed by continuous infusion hydrocortisone @ 200mg/24hrs (or 50mg IM every 6hrs) until the pt can take double their PO glucocorticoid dose. Taper it back to the appropriate maintenance dose, usually 24-48hrs (unless vomiting or nbm, may be up to a week of higher glucocorticoid requirement if major/complicated surgery).
The above only applies for major surgery. And dexamethasone 6-8mg IV would suffice as supplementation for 24hrs. Postop, once PO intake allowed, resume the enteral glucocorticoid @ pre-surgical therapeutic dose if the surgery is uncomplicated, otherwise continue double oral dose for up to 1/52.
For body surface or intermediate surgery, postop have double regular glucocorticoid dose for 48hrs then continue usual Rx if the surgery was uncomplicated.
For bowel prep procedures, continue normal dose (IV equivalent if NBM), add in the stress hydrocortisone as for primary/secondary if concerned about HPA function.
Why is dexamethasone inappropriate as glucocorticoid treatment in pts w primary adrenal insufficiency?
It has no mineralocorticoid activity
Where should pts w adrenal insufficiency be placed on the surg operating list?
First, since fasting times should be minimised (tolerate fasting & dehydration poorly)- children w adrenal insufficiency are more vulnerable to problems with glycemic control than adults, they require frequent bgl monitoring (hourly if fasting >4hrs). NO child w adrenal insufficiency should be fasted for >6hrs. Postop, monitor hourly BGL until enteral intake resumed.
How should obstetric pts w adrenal insufficiency be managed?
May require higher maintenance doses from 20/40 onwards, require stress supplementation of hydrocortisone 100mg IV (or IM) @ onset of active labour then continuous IV hydrocortisone 200mg/24hrs or 50mg IM every 6hrs, until delivery
Double hydrocortisone doses for 48hrs when resume enteral
What’s the dominant glucocorticoid in humans? where’s it produced? How much is produced each day?
Cortisol, in the zone fasciculata of the adrenal cortex
up to 20mg/day produced, in pulsatile form following a circadian rhythm
Where is ACTH produced?
Anterior pituitary
How much cortisol can be produced following the stress of uncomplicated major elective surgery? How long dose cortisol take to return to baseline, provided protracted critical illness (which reduces metabolism & clearance of cortisol) doesn’t occur?
5-fold increase above baseline, up to 100mg cortisol/day
24-48hrs
What are the recommendations of the AAGBI for pts w primary or secondary adrenal insufficiency undergoing procedures requiring bowel prep?
Bowel prep should be done under clinical supervision.
Consider IVT & hydrocortisone during preparation, especially for fludrocortisone or vasopressin-dependent pts
Give hydrocortisone 100mg IV or IM @ the start of the procedure
When resume PO intake, should have double hydrocortisone doses for 24hrs
What’s the regimen for intra- and postoperative steroid cover in children with adrenal insufficiency?
Major surgery: hydrocortisone 2mg/kg induction followed by continuous IVI based on weight:
-up to 10kg: 25mg/24hrs
-11-20kg: 50mg/24hrs
-over 20kg:
100mg/24hrs if prepubertal, 150mg/24hrs if pubertal
Postop, continue the infusion (if unstable or sepsis), otherwise give 2mg/kg IV or IM 4-hourly, for major surgery
Once PO, double usual dose of hydrocortisone for 48hrs then reduce to normal doses over up to 1/52. Add in fludrocortisone if appropriate when enteral feeding established.
Minor surgery under GA: 2mg/kg IV or IM @ induction. Double hydrocortisone once enteral feeding established, continue double dose for 24hrs. Add on fludrocortisone if appropriate.
Minor procedures not requiring GA: double mane hydrocortisone given pre-op, normal hydrocortisone postop
What are some examples of primary adrenal insufficiency? What will be the pts deficiencies? how do the deficiencies differ cf secondary?
Addison’s disease (autoimmune adrenal insufficiency) & congenital adrenal hyperplasia
Pts will be deficient in cortisol & aldosterone production for primary.
for secondary they’ll also be deficient in cortisol but will still produce aldosterone in response to renin
