3 Uterine Thyroid Osteoporosis Flashcards
Hormones that cause uterine contraction
Estrogens
Prostaglandins
Oxytocin
Stretching
Hormones that cause uterine relaxation
Beta-adrenergic drugs (not used any more)
Progesterone
Alcohol
MgSO4
______ and ______ of oxytocin receptors in the uterus increase just prior to labor and delivery
Number and sensitivity
DOC for inducing labor at term
Oxytocin
Why are prostaglandins useful in inducing abortion?
Uterus is generally resistant to stimulation during the second trimester but prostaglandins can cause strong labor-like contractions during this time
Major cause of delivery-associated deaths
Postpartum hemorrhage (4-20% of deliveries have PPH)
________ is the cause of 80% of all postpartum hemorrhage
Uterine atony
Uterus doesn’t have enough contractility after delivery
First line treatment for postpartum hemorrhage
Uterine massage
WHY? Causes release of oxytocin —> constriction of the uterine arteries
Cyclic octapeptide store in posterior pituitary normally released in response to suckling and cervical pressure
Oxytocin (Pitocin, Syntocin)
Indications/therapeutic effects of Oxytocin
DOC to induce labor at term if indicated
- uterine dysfunctional inertia
- causes timed contractions (more physiological)
- IV infusion used
For prevention of postpartum hemorrhage (IM route preferred)
For stimulation of milk let-down reflex (NASAL application via cotton pledget)
Adverse effects of Oxytocin
Water intoxication (ONLY AT LARGE DOSES) - b/c of ADH like effect of oxytocin
UTERINE RUPTURE with large dose
Allergy
Anaphylaxis
Sinus bradycardia of the fetus —> Caesarian
Contraindications for Oxytocin
Basically, if it’s not time to deliver, don’t administer
Malpresentation Cephalopelvic disproportion Complete placenta Previn Uterine scar form previous Caesarian Unengaged head Cervical scarring
What drugs are ergot alkaloids
Ergonovine maleate
Methylergonovine maleate
MOA for ergot alkaloids
Contraction of uterine smooth muscle through activation of serotonin and alpha-adrenergic receptors - powerful vasoconstrictors
Indications for the use of ergot alkaloids
After completion of labor and the delivery of the placenta, to produce firm uterine contractions and to decrease uterine bleeding
2nd line after massage and oxytocin have failed for PPH
To produce contractions following suction abortion
Adverse effects of ergot alkaloids
Transient hypertension (b/c it contracts all smooth muscle) Angina, MI
Contraindications for Ergot alkaloids
Should NEVER be used to induce labor - only AFTER DELIVERY (because it causes the wrong kind of contractions, will cause fetal hypoxia)
Peripheral vascular or coronary artery disease - increases BP
Dinoprostone is a synthetic ________ indicated for the expulsion of uterine contents
Prostaglandin
Used in cases of intrauterine fetal dearth, missed abortion (miscarriage), and elective abortions
Can also cause cervical ripening prior to delivery at term
How is Dinoprostone administered?
For abortion: one suppository in the vagina (woohoo)
For cervical ripening: apply gel to cervix
Adverse effects of Dinoprostone
GI disturbances - vomiting, DIARRHEA** (black box)
Fever, chills, H/A
Many common but not serious (use correct dose)
Contraindications for Dinoprostone
Fetal distress, history of difficult deliveries
For abortions, should not be used in patients with:
- Acute pelvic inflammation
- Acute cardiac, pulmonary, renal, or hepatic diseases
- Asthma, HTN, anemia, jaundice, or epilepsy
What is Carboprost tromethamine?
A prostaglandin (PGF2a derivative) used for the induction of abortion in 13th to 20th week (2nd trimester) or for postpartum bleeding due to uterine atony
Administered IM
Adverse effects of carboprost tromethamine
Not serious if used properly, systemic PG actions often diagnosed as anaphylactic shock
Vomiting and diarrhea in >60%
Fever and rashes
Contraindications for carboprost tromethamine
Should not be used in patients with
ACUTE PELVIC INFLAMMATION
Acute cardiac, pulmonary, renal, or hepatic disease
Asthma, HTN, anemia, jaundice or epilepsy
Anti-fibrinolytic agent used to reduce death due to bleeding in women with postpartum hemorrhage
Tranexamic acid
Given IV along with standard uterotonic therapy (should NOT be regarded as an alternative therapy)
First line drug for prevent premature labor
Magnesium Sulfate
Can also prevent convulsions in pre-eclampsia and treat eclampsia
Why must MgSO4 be administered slowly?
Significant hypotension or asystole if too fast
How is Nifedipine used during pregnancy?
To prevent pre-term labor (tocolytic agent)
Inhibitors Ca2+ influx (and smooth muscle contractions)
Becoming the 1st line agent
Why should you never give Nifedipine with MgSO4?
CV collapse due to severe hypotension
_________ is an anti-inflammatory drug that has been investigated for its ability to delay preterm labor
Indomethacin
Trials show reduced frequency of delivery within 48 hours and within 7-10 days from the beginning of treatment
How does Indomethacin work as a tocolytic agent?
Inhibits COX enzyme —> reduction in prostaglandin synthesis (and prostaglandins cause contractions, so that’s that)
Adverse effects of indomethacin as a tocolytic agent
Maternal GI irritation
Partial closure of the fetal ductus arteriosus
How is progesterone used in preventing preterm birth?
More effective than placebo in maintaining the length of pregnancy when GIVEN PROPHYLACTICALLY from the 16th-37th week of pregnancy or until delivery
Not effective for acute treatment
Recommended for women at high risk with a history of preterm birth
Approved for use in ART to maintain the luteal phase following IVF or ICSI
How is nitroglycerin used in pregnancy?
EMERGENCY USE ONLY in case of uterine rupture
What was used historically to inhibit premature labor?
Ethanol. Yup.
Works though, if you have NOTHING ELSE
Direct relaxant effect on the myometrium and inhibits oxytocin release
Agents used in the past for premature labor but no longer due to the overwhelming cardiac problems associated with its tocolytic use
B2 adrenergic agents - Terbutaline and Ritodrine
Drug of choice for hypothyroidism
Levothyroxine sodium - T4 replacement
What do you need to know about Levothyroxine
Drug levels must be carefully titrations to the individual and vary brand to brand - monitor TSH levels and patient Sx
4-6 weeks for stead state
How is Liothyronine sodium (Cytomel) used?
T3 - used for initial therapy (quicker steady state levels) but not for maintenance in thyroid replacement
MYXEDEMA COMA
Side effects of Levothyroxine
Similar to hyperthyroidism
Reduce dose or stop for a few days and resume at a lower dose
Treatment for hyperthyroidism
Remove the gland via surgery
Destroy the gland with I-131
Reduce T4/T3 with thiazides/iodide
Block symptoms - BETA BLOCKERS
First line treatment for Grave’s disease
Thioamides - Propylthiouracil or Methimazole
Inhibit synthesis of T4
PTU only - blocks conversion of T4 to T3
What is the black box warning for PTU?
Severe liver injury, acute liver failure
Thus Methimazole is preferred unless allergies or PREGNANCY
DOC for Graves in pregnancy
Propylthiouracil (PTU) - doesn’t cross placenta as well
Why do you need to watch for sore throat and do blood tests on thioamides?
Risk of granulocytopenia and agranulocytosis
How is iodide used in the treatment of hyperthyroid?
Rapidly decreases synthesis and release of T4/T3 - good for short-term effect
Used for 7-10 days before surgery to decrease likelihood of thyroid storm
Can be used in radioactive emergencies
How is radioactive iodine (I-131) used in hyperthyroidism?
Small amounts diagnostic (uptake and scan)
Large amounts destroy gland
Used in elderly patients and those with heart disease for definitive treatment of Graves’ disease (but thioamides preferred)
Preferred treatment for toxic nodular goiter
Radioactive Iodine (I-131)
Contraindications for Radioactive Iodine use
PREGNANCY, nursing, or mothers who lack childcare
How is Propranalol used in hyperthyroidism?
Non-specific beta blocker, but it specifically inhibitors the peripheral conversion of T4 to T3 in addition to helping with the symptoms of hyperthyroidism
Used to prepare for surgery and for those waiting for other treatments to take effect
What is always given in conjunction with other treatments for osteoporosis?
Calcium and Vitamin D
DOC for osteoporosis
Bisphosphonates
+ Calcium and Vit D
+/- HRT
+/- Calcium regulating hormones (PTH, calcitonin)
How is Calcitonin used in treatment of osteoporosis?
Reduces bone resorption of Ca2+ and antagonizes parathyroid hormone
Indicated for Osteoporosis (though not first line)
DOC for Paget’s disease
What drugs are the only anabolic drugs for osteoporosis?
Parathyroid drugs, b/c RG receptor activation can stimulate formation of new bone
Examples: Teriparatide, Abaloparatide, rhPTH
Adverse effects of parathyroid drugs
Hyperkalemia and hypercalciuria
Contraindicated in OSTEOSARCOMA (b/c rats)
Antibody against receptor activator of nuclear factor kappa-beta ligand (RANK-L)
Denosumab
Inhibits bone resorption
RANK-ligand is the factor made by osteoblasts that is necessary for the formation of mature osteoclasts —> inhibitors resorption
Indications for Denosumab
Osteoporosis in men and postmenopausal women at high risk for fractures, esp those with cancer
Increases bone mass and strength in both cortical and trabecular bone
MOA for bisphosphanates
Substitutes for PO4 in Ca2+ binding —> incorporates into bone —> inhibition of osteoclasts activity and bone resorption
First line treatment for post-menopausal osteoporosis
Bisphosphonates
What are the special pharmacokinetics of bisphosphonates?
Absorption is very poor
Must be taken on an empty stomach with exactly 1/2 glass of water and stay upright for 30 min after taking to decrease esophageal irritation
