Endocrine Flashcards
Diagnosis of DKA
- Glu >= 11.1
- AG > 10
- HCO3 < 15
- pH < 7.3
- moderate ketonuria/ketonemia
Rapid acting Insulins
Apidra/Humalog/NovoRapid
Onset: 10-15 min
Peak: 1-2 h
Duration: 3-4 h
Short-acting Insulins
Humulin-R/Toronto
Onset: 30 min
Peak: 2-3 h
Duration: 6h
Intermediate-acting Insulins
Humulin-N/NPH
Onset: 1-3 h
Peak: 5-8 h
Duration: Up to 18 h
Long-acting Insulins
Lantus
Levemir
Onset: 90 min
Peak: None
Duration: Lantus, 24h; Levemir 16-24h
Humulin 70/30
70% NPH
30% Humulin R
For Novolin, etc., higher number is NPH, lower is regular
Usually given BID with meals.
General dosing of insulin
0.5-1 unit/kg/day
50-75% given as long acting or intermediate, rest given preprandially
Target Organ Damage in HTN
Stroke
Dementia
Hypertensive Retinopathy
LVH
CAD
CKD
PAD
When & How to screen for renovascular HTN
>=2 of:
- sudden onset/worsesning at >55 or
- abdominal bruit
- HTN resistant to >=3 drugs
- Cr rise >=30% with ACE/ARB
- other atherosclerotic vascular disease
- recurrent pulmonary edema with HTN surges
Investigations: captopril-enhanced radioisotope renal scan (if eGFR >60), renal doppler, MRI, or CT angio.
When to screen for hyperaldosteronism?
- HTN with spontaneous hypo K (
- HTN with marked diuretic induced hypo K (
- HTN resistant to >=3 drugs
- HTN with incidental adrenal adenoma
When to screen for pheo
- paroxysmal or severe (>180/110) HTN refractory to usual therapy
- HA’s, palps, sweating, panic attacks, pallor
- HTN triggered by BB’s, MAOI’s, micturition, changes in abdo pressure
- HTN with adrenal mass or HTN with MEN 2A/2B
Management of subclinical hypothyroidism
- subclinical (increased TSH but normal FT4): pregnancy TSH >2.5, TPO Ab +ve, TSH >10,
- monitor Q12 months, ~10%/year progress to clinical
Treatment of hypothyroidism
- LT4 12.5-50 mcgs/day
- Increase Q4-6 weeks
- Males: 125-200 mcgs/day
- Females: 75-122 mcgs/day
- In young healthy patients, may start at full dose right away
Causes of Hyperthyroidism
- Graves: 60-80%, antibodies against TSH receptor
- TMNG: 5%, insiduous, >40 years old
- Toxic adenoma: younger pts in iodine-deficient area
-
Thyroiditis
- subacute: resolves in 8 months
- lymphocytic + postpartum
- treatment-induced: iodine, amio
- tumour: metastatic thyroid cancer or ovarian cancer
Management of Thyroid Storm
- sublinical: treat if TSH
- betablockers: propranolol 10-40 mg, atenolol 25-100 mg, metoprolol 25-100 mg
- methimazole: 5-120 mg for 12-18 months then taper, DC if asymptomatic + normal TSH
- radioactive iodine
- subtotal thyroidectomy: treatment of choice in pregnancy + young patients
Labs for DKA
- cap glucose, urine dip, ECG
- CBC, GBCL, ext lytes, VBG, lactate, urinalysis, +- serum ketones
- urine dip only detects AcAc, actually worsens with rehydration as bHB and AcAc in equilibrium and bHB favoured in low-flow states
-
then
- ext lytes, VBG Q2-4h
- CBG Q1h
DKA Fluids Adult
- average adult deficit is 5-10 L
- 1-2 L NS in first hour
- then NS @ 250-500 mL/h (0.45% NS in hypernatremic/eunatremic patients)
- generally 2L in 0-2h, 2L in 2-6h, 2L in 6-12 h
- When glucose <14, change to D5W 0.45% NS
DKA Fluids Children
- 5-10mL/kg NS boluses while hypotensive
- then NS at 1.5x-2x maintenance
K+ Management, DKA
- most adults need 100-200 mEq in first 24h
- if <3.3, hold insulin,
- if 3.3-5, give 10-20 mEq/h IV (then PO when tolerating)
- >5, hold potassium
- basically add 20-40 mEq/L to IVF for kids and adults when K+ <5.0 and peeing
DKA Insulin Management
- after fluid bolus, or through second IV line, give regular insulin (e.g. Humulin R) at 0.1 unit/kg/h, once confirmed that K is >3.3
- decrease drip rate once euglycemic and add D5W
- target glucose 8.3-11
- once eating, stop D5W
- once gap closed, pH normal, bicarb > 18 and eating
- 10 units Humulin R 30-60 minutes before stopping infusion
- 80% of usual long-acting insulin 1-2 h before stopping infusion
- 0.1-0.2 units/kg if newly diagnosed
DKA Cerebral Edema Dx & Mgmt
- young, newly diagnosed
- improving then headache, LOC changes, incontinence
- prevent by slow correction
- IV mannitol 1-2 g/kg or hypertonic saline (3%) 5-10 mL/kg over 30 minutes
Rhabdomyolysis
-
Dx
- CK > 5x ULN
- peaks 24-72 h
- falls at 39% per day
- level does not correlate with risk of renal failure
- myoglobin in urine (but falls 6h after onset of muscle breakdown)
- check extended lytes, CBC, PTT/INR (for DIC), uric acid, LDH
- often initial hypocalcemia (later hypercalcemia), hyperphos, hykerK
- monitored bed
- CK > 5x ULN
-
Tx
- NS alternating with D5NS
- don’t use Ringer’s
- no evidence for bicarb or diuretics
- aim for UO of 2mL/kg/h (200-300 mL/h)
-
Dispo
- if purely exertional and mild may rehydrate and DC home
- otherwise admit to monitored bed
Adrenal Gland Structure (Read-Through)
- adrenal cortex
- cortisol
- controlled by CRH, ACTH, HPA
- highest in AM, lowest in evening
- controlled by CRH, ACTH, HPA
- aldosterone
- controlled by RAAS & K+ levels
- sex hormones
- cortisol
- adrenal medulla
- adrenaline, noradrenaline, dopamine
Symptoms of adrenal insufficiency (cortisol + aldosterone)
- cortisol: weight loss, lethargy, weakness, decreased LOC, anorexia, NxVx, AP, diarrhea
- aldosterone: dehydration, syncope, salt craving, orthostatic hypotension
Serum cortisol level to r/o adrenal insufficiency
- serum cortisol > 18 mcg/dL rules out adrenal insufficiency
Addison’s Disease
labs
causes
treatment
- cortisol, aldosterone, sex hormone deficiency
- ACTH excess –> hyperpigmentation
- cortisol does not rise with ACTH stimulation test
- hyponatremia, hyperkalemia
- autoimmune, sepsis, ketoconazole, TB, infiltrative disorders (ca, sarcoid, etc.), sx, CAH/familial
- tx lifelong fludrocortisone (Florinef) + glucocorticoid
- women may need androgens (men make in testes)
Secondary Adrenal Insufficiency
labs
causes
treatment
- cortisol deficiency only
- cortisol rises with ACTH stimulation test
- hyper or hyponatremia, hypokalemia (functioning aldosterone)
- sudden cessation of chronic steroid use, pituitary apoplexy/tumor/radiation/infiltration/infection
- tx glucocorticoid only
Stress-Dose Steroids
- 3x daily dose of glucocorticoid dose (give for 24-48 h with f/u to pts with minor illness)
- mineralocorticoid dose usually stays the same
Adrenal Crisis
ssx
tx
- hypotension refractory to pressors
- nxvxdx AP
-
tx
- Hydrocortisone 100 mg IV bolus (has glucocorticoid + mineralocorticoid effects)
Pediatric Hypoglycemia
See Evernote “Peds Metabolic Disorders”
Inborn Errors of Metabolism
- nonspecific presentation
- poor feeding/vx +- acidosis
- routines, LFT’s, ammonia level, VBG, lactate, urine ketones
- ammonia level
- normal <65 mm/L
- can be 2-3x higher in stressed/nonfasting newborns
- > 200 definitely abnormal
- Stop feeding
- Start D5WNS
Peds Adrenal Insufficiency
- 95% is 21-hydroxylase deficiency
- classic salt-wasting, virilizing
- all end up in cortisol deficiency but some non salt-wasting
- classic salt-wasting presents during 2-5th weeks of life in crisis
- hypo Na+, Hyper K+, metabolic acidosis, virilizing features, skin fold pigmentation
- NS
- correct hypoglycemia
- Hydrocortisone
- 25 mg IV neonates
- 50 mg IV toddlers/school-aged children
- 100 mg IV adolescents
How to treat new Dx Diabetes with Hyperglycemia but no DKA
- fluids
- 0.1 u/kg sc Humulin R
How to treat hyperglycemia in known DM but no DKA
- 10% total daily insulin dose as Humulin R
- 5-10% Q4-6h until illness resolves/ketonuria resolves if T2DM with intercurrent illness but no DKA
Management of Hyperthyroidism (non-storm)
- metoprolol 25 mg PO BID
- med clinic
Target rate of glucose drop in DKA
2-5 mmol/L/h
