Endocrine Flashcards
1
Q
Thyroid hormone (T3 and T4)
A
Thyroid hormone
- regulate basal metabolic rate
- by increasing, body temperature also increases
- thyroid affects numerous other processes, affecting nearly every cell in th body
- life-long medication management of thyroid issues
- DO NOT suddenly stop medication - can send them into crisis
- hypothalamus secretes TRH –> TRH stimulates pituitary gland to secrete TSH –> TSH stimulates thyroid gland to secrete T3 and T4
- negative feedback system - as thyroid hormone levels increase, negative feedback supresses the secretion of TSH and TRH.
- High levels of iodine can also cause a temporary decrease in thyroid activity that can last for several weeks
Hypothyroidism
-
Cause: results from either a poorly functioning thyroid gland or low secretion of TSH by the pituitary gland
- Most common cause: Hashimoto’s thyroiditis or chronic autoimmune thyroiditis - results in destruction of the thyroid gland
-
Clinical Manifestation:
- early symptoms: general weakness, muscle cramps, dry skin
- more severe symptoms: slurred speech, bradycardia, weight gain, decreased sense of taste and smell, intolerance to cold enviroinments
- Goiter may be absent or preesent depending on the cause of disease
- Lab results generally revealed elevated TSH with diminished T3 and T4 levels
-
Tx: levothyroxine (Synthroid, Levothroid)
- take on EMPTY stomach in MORNING
- do not take SOY PRODUCTS w/in 1 - 4 hrs
- do not take CALCIUM w/in 4 hrs
- Watch iodine
- Contraindications: use for weight loss
-
Misc. Management:
- serum TSH levels used to eval progress of therapy
- avoid switching bands of medicatin once condition has stabilized
Hyperthyroid
- Causes:
- Most common type of hyperthyroidism: Graves’ Disease - autoimmune disease;
- Other causes are adenomas of the thyroid, pituitary tumors, and pregnancy
-
Hypersecretion of thyroid hormones:
- increased body metabolism, weight loss
- tachycardia, elevated body temp
- anxiety
- If left untreated, can cause thyroid storm
- s/s:
- high fever
- CV effects (tachycardia, heart failure, angina, MI)
- CNS effects (agitation, restlessness, delirium, progressing to coma)
- s/s:
-
Treatment:
- surgical removal of part or all of thyroid gland
-
antithyroid drugs - hepatotoxic
-
methimazole (tapazole)
- NOT BABY SAFE; pregnancy D
- if pregnant notify physician asap
- NOT BABY SAFE; pregnancy D
-
propylthiouracil (PTU)
- BABY SAFE
-
methimazole (tapazole)
2
Q
antidiuretic hormone (ADH)
A
-
posterior pituitary gland directly secretes ADH that acts on collecting ducts of kidneys to increase water reabsoprtion
- ADH
- regulates body fluid
- acts as vasoconstrictor
- ADH
-
Deficiency of ADH
- diabetes insipidus - production of large volumes of very dilute urine
-
S/S:
- polyuria -
- polydipsia -
-
Tx:
- acts on kidneys to help reabsorb water, reduce urination → increase reabsoprtion of water
-
desmopressin
- make sure sodium levels are normal before administering, otherwise may use other drug
- vasopressin
-
Monitor:
-
blood pressure (increase circulatory volume → increased BP, increased HR)
- monitor esp. if underlying CV issues
-
blood pressure (increase circulatory volume → increased BP, increased HR)
- Precaution: acute or chronic renal disease