Female Reproductive Cycle I

1. Female Reproductive Cycle I Pregnancy and Preterm Labor Drugs

2. Review A&P of female reproductive system Feedback loop (pg. 808)

3. Physiological Changes • Altered hepatic metabolism of drugs • Reduced GI motility • Increased GI pH • Increased GFR-more rapid excretion • Expanded blood volume = dilution • Alteration in drug clearance • Implications: Drug dosages and dosing intervals should be considered

4. Placenta • Allows for the exchange of many substances including medications • Speed of exchange/transfer varies • Maternal and fetal blood flow • Molecular weight of the substance being exchanged • Degree of ionization (does it have a charge) • Degree of protein binding (↑ do not cross readily) • Metabolic activity of the placenta • Maternal dose

5. To Prescribe or Not to Prescribe Risk/Benefits MD/NP must consider the aforementioned physiological changes

6. The Fetus Liver metabolism is slower What we give the mother can have prolonged effects on the fetus Impact fetal outcome

7. Lactation Remember the ways that drugs cross the placenta—same can be applied to breast tissue. Know drugs that accumulate in the breast tissue because these drugs can be transported to the infant during feeding. Your role in teaching the mother cannot be underestimated.

8. Other Considerations • Legal and illicit drugs • Mother’s underlying conditions still need to be treated • Seizure disorders • Diabetes • HTN • OTC drugs • Cold remedies, stool softeners, pain medications • FDA Category system-revisit

9. Teratogens Terat/o – greek monster -gen = to produce Substances that are teratogenic are those that produce birth defects/developmental abnormalities Period of possibility begins 2 weeks after conception Weeks 2-10 organogenesis Timing, dose and duration of exposure

10. Fetal Effects Table 52-1 Review

11. Therapeutic Drug and Herbal Therapy

12. Iron

13. Folic Acid

14. Multiple Vitamines

15. Drugs for Discomfort

16. Nausea and Vomiting

17. Heartburn

18. Constipation

19. Pain

20. Drugs to Decrease Uterine Muscle Contractility

21. PTL PTL that progresses to PTD accounts for most prenatal morbidity and mortality in US (excluding fetal abnormalities) No one cause

22. Risk Factors • Younger than 18 but older than 40 • Low SES • Previous hx of PTL • Intrauterine infections • Polyhyraminos • Multiple gestation • Uterine abnormalities • Antepartum hemorrhage • Smoking • Incompetent cervix • UTI

23. PTL-Continued • Goal is to stop the preterm labor • Tocolytics Contraindicated in: • Pregnancy ↓ 20 wks gestation (ultrasound) • Considered a miscarriage • Bulging or PROM • Confirmed fetal death or anomalies incompatible with life • Maternal hemorrhage and severe fetal compromise • Chorioamnionitis

24. Tocolytic Therapy in Absence of Contraindications • Beta2 agonists (Beta Sympathomimetics) • Terbutaline (Brethine) • Recall Table 17-1 Page 268 • Beta2 receptors are located in uterus • An agonist produces a response • Giving a Beta2 agonist will relax the uterus • Giving a Beta2 antagonist (Beta-Blocker) would have the opposite effect. • Calcium antagonist • Magnesium Sulfate (Mag Sulfate)

25. Goals of Tocolytic Therapy Interrupt uterine contractions to provide additional time in utero Delay delivery so corticosteroids can be given to promote fetal lung maturity Allow safe transport to another facility if needed

26. terbutaline (Brethine) • SQ/oral/IV • Minimally protein bound • Half life 11-16 hours • IV/SQ • Onset 15 minutes • Peak 30-60 minutes • Duration 1-4 hours (SQ)

27. Nursing Process/Brethine Assessment Diagnosis Plan Interventions Evaluation Review 822

28. Magnesium Sulfate Calcium antagonist (blocks response) CNS depressant ***** Fewer side effects than Brethine Given IV Dose is titrated to keep contractions under control Need to draw magnesium levels Contraindicated –myasthenia gravis, impaired kidney function, recent MI

29. Adverse Reactions Low blood pressure Flushing Sweating Dizziness Nausea Headache Lethargy Slurred Speech Increased pulse rate

30. Remember To: • Assess for neuro, respiratory or cardiac depression. • Antidote: Calcium Gluconate (10 mg IV Push over 3 minutes) • Assess magnesium levels 4-7 mg/dL • Loss of patellar reflexes often first sign of toxicity-8-10 mEq/L • Respiratory depression-Levels greater than 10-15 mEq/L • Cardiac Arrest-Levels greater that 20-25mEq/L

31. Nursing Process Page 827

32. Nursing Process-Mag Sulfate Assess and monitor-Respirations, FHR, fetal activity, I&O, breath and bowel sounds, DTR, weight, have antidote on hand---- Diagnose Plan Implement Evaluate

33. Corticosteroids in PTL

34. Surfactant Development • Clients at risk for PTL • Accelerates lung maturation and lung surfactant development • Decreases RSD • Increases survival • L/S ratio predicts fetal lung maturation • Lecithin/sphingomyelin

35. Corticosteroids in PTL • Betamethasone (Celestone) • Seizures, headache, HTN, petechiae, ecchymoses, facial redness • Dexamethasone • Insomnia, nervousness, increased appetite, arthralgia, hypersensitivity reactions • See Nursing Process for Betamethasone pg. 823

36. Drugs for Gestational HTN

37. Defined Elevated BP without proteinuria after 20 wks. Had normal BP to begin with. Categories of GHTN Preeclampsia: Gestational hypertension withproteinuria. Eclampsia: New-onset grand mal seizures in client with preeclampsia.

38. Preeclampsia Systolic greater than 140mm/Hg or diastolic greater than 90mm/Hg Proteinuria greater than 300mg in a 24 hour urine collection After 20th week Graded as mild to severe

39. HELLP Syndrome Hemolysis Elevated Liver Enzymes Low Platelet Count

40. Goals Uncomplicated delivery Psychological support for client/family Reduction of vasospasm Prevention of seizures

41. Cure for Preeclampsia Delivery

42. First Line Therapy FIRST LINE ALTERNATIVES methyldopa (Aldomet) hyralazine (Apresoline) labetalol (Trandate) Beta-blockers Prazosin Nifedipin Clonidine