Endocrinology Flashcards

Question

Discuss the pathophysiology of diabetic ketoacidosis

Answer 1

Severe Insulin Deficiency - stress increase insulin demand that is not matched by pancreas - decrease peripheral glucose utilization and uptake, leading to hyperglycemia - K shift out of cell leading to hyperkalemia with low body store of K Severe Cell Starvation - liver produce and release glucose -> hyperglycemia - adipose tissue release free fatty acids which are converted to ketones by liver - peripheral muscle decrease glucose utilization leading to weakness Ketone Bodies - cause metabolic acidosis, which can be compensated by breathing Hyperglycemia and Ketone Bodies - cause osmotic diuresis - dehydration - electrolyte depletion - hyperosmolality (hyponatremia and cerebral dehydration)

Answer 2

``` Presentation - sleepiness, LOC - blurry vision - N/V - polyuria, polydipsia - Kaussmaul breathing - hypovolemic - fruity ketone breath Investigation - CBC, electrolytes, creatinine BUN - blood glucose - serum osmolality - serum ketone - VBG - urine analysis - ECG Diagnosis (all of the following) - metabolic acidosis with increased anion gap - serum and urine ketone bodies - hyperglycemia ```

Answer 3

- Q2-4H electrolytes, anion gap, glucose, creatinine, plasma osmolality, LOC IV Fluids for decreased Effective Circulating Volume - Severe shock give NS 1-2L/h until hypotension correction and then switch to NS 500mL/hr for 4hr then 250mL/hr for 4 hr - mild to moderate start at 500mL - Once euvolemic - Na is normal/high or rate of plasma osmolality fall is <3 switch to 0.45NS - Na is low or rate of plasma osmolality fall >=3 then continue with 0.9%NS - Once plasma glucose reaches 14 add D5W to IV fluids to maintain glucose 12-14 Serum K - <3.3 then give 40mmol/L KCl and no insulin until K >=3.3 - >=3.3 and less 5-5.5 then 10-40KCl Acisosi - if K <3.3 correct hypokalemia before insulin - if K >=3.3 administer IV short acting insulin 0.1unit/kg/h - adjust rate of insulin based on anion gap resolution - if pH <7.0 then NaHCO3 1 amp/h until pH >=7

Answer 4

Primary - thyroid gland not making enough thyroid hormone - high TSH low T3/T4 - autoimmune hypothyroidism from Hashimoto's - iodine induced - drug induced (amiodarone) Secondary - central where failure of pituitary stimulation of thyroid hormone - low TSH and T3/T4 - pituitary disease (tumour)

Answer 5

``` Presentation - weight gain - dry/itchy/cold/coarse skin - hair loss - fatigue - cold intolerance - depression, psychosis - joint pain and muscle cramps - muscle weakness - constiptation - menstrual irregularities and menorrhagia - myxedema (non pitting edema) - puffiness with coarse brittle hair (eyebrow) - peri-orbucular swelling - enlarged tongue - goitre - delayed deep tendon reflex - carpal tunnel syndrome - bradycardia and diastolic hypertension Investigation - TSH and Free T3/T4 - subclinical T4 may be normal ```

Answer 6

``` Levothyroxine - synthetic T4 (body can convert to T3) - start at 1.7mcg/kg/d - monitor response at 6 weeks - primary target to TSH <5 - in pregnancy may require more and target is <2 Indications - TSH >10 - Symptomatic - Subclinical and pregnancy - hypertension, hypercholesterolemia ```

Answer 7

``` Primary - thyroid gland overproduce thyroid hormone despite good negative feedback loop - TSH low and Free T3/T4 high - autoimmune: Grave's - toxic nodular goitre - hyperthyroid phase of acute thyroidits - excessive synthroid, amiodarone, iodine in diet Secondary - pituitary excrete excessive TSH - high TSH and T3/T4 - pituitary adenoma ```

Answer 8

``` Presentation - heat intolerance, sweating, weight loss - anxiety, insomnia - palpitation - muscle aches, hyperactivity - frequent bowel movements - loss of libido - moist skin - tremor - diffuse goitre and bruit - tachycardia and systolic hypertension - palmar erythema, onycholysis - lid lag, proptosis - hyperreflexia - pretibial myxedema Investigation - TSH, T3/T4 - Radioactive Iodine Uptake ```

Answer 9

``` Graves - low TSH - very High T3/T4 - very High Radioactive uptake Toxic Nodule - low TSH - high T3/T4 - high radioactive uptake Subacute thyroiditis - low TSH - high T3/T4 - low radioactive iodine uptake - high thyroglobulin Factitious Thyrotoxicosis - low TSH - high T3/T4 - low radioactive iodine uptake - low thyroglobulin TSH Secreting tumour - high TSH - high T3/T3 - high radioactive iodine uptake ```

Answer 10

``` Antithyroid Drugs - Methimazole and Propylthiouracil - inhibit thyroperoxidase - PTU also inhibit deiodinase that convert T4 to T3 - PTU used in pregnancy Radioactive Iodine - cure Grave disease, multi nodular goitre or toxic nodule - can not use in women if wanting to get pregnant in next 6 months Subtotal surgical Thyroidectomy - last line Beta Blocker - symptomatic - propanolol ```

Answer 11

Primary - decreased production of glucocorticoid from adrenal cortex - Addison' - TB, HIV - congenital adrenal hypoplasia Secondary - Decreased ACTH from pituitary resulting in decreased glucocorticoid production from adrenal cortex - hypopituitarism - pituitary adenoma or stalk trauma - suppression of ACTH from withdrawal of exogenous steroids Tertiary - decreased CRH from hypothalamus resulting in decreased ACTH

Answer 12

Presentation - weakness, weight loss - N/V - hypotension and postural dizziness - visual field defect if pituitary adenoma - hyponatremia - primary: dark skin and mucosa from ACTH, metabolic acidosis - secondary: hypothyroidism and hypogonadism Diagnosis - low plasma cortisol at 8am or low plasma cortisol despite ACTH stimulation - primary high ACTH and low cortisol and persistent low cortisol despite stimulation - secondary/tertiary low ACTH and cortisol, increased cortisol in response to ACTH stimulation Management - hydrocortisone 15-20mg daily divided BID-TID - increase 2-3x if mod-severe illness - large dose 150-300mg IV daily divided TID for major stress (surgery, trauma) - medical alert bracelet for IM hydrocortisone if suffer major stress

Answer 13

``` - inappropriate cortisol production in response to stress Presentation - N/V - confusion - shock/hypotension - hypoglycemia Management - obtain blood sample for ACTH, cortisol and electrolyte - Immediate: - IV NS 2-3L bolus - D5W if hypoglycemic - hydrocortisone 50-100mg IV Q6-8H for 24hr then taper ```

Endocrinology Flashcards

(37 cards)