OB and labor complications QUIZ 4 Flashcards
What is the mean duration time of pregnancy?
40 weeks from the first day of last menstrual period
How long is “term”?
37 weeks completed to 42 weeks
How many births are pre-term and what percent of morbidity and mortality does it account for?
7-12% of deliveries in the U.S and accounts for over 80% of morbidity and mortality
What weight is considered low birth weight?
any infant under 2500 grams
What is considered VERY low birth weight?
any infant under 1500 grams
At ____ weeks gestation, ___ % of EFW are under ___ grams
At 29 wks GA, >90% of EFW are < 1500g.
Mortality approaches ___% for infants born <24 wks; survival exceeds 90% >30 wks, to >98% by 34 wks.
Mortality approaches 90% for infants born <24 wks; survival exceeds 90% >30 wks, to >98% by 34 wks.
How much does survival increase by each day between 25 and 26 weeks?
~5% each DAY!
What are the prematurity comorbidities?
Respiratory Distress Syndrome
- Exacerbated by intrapartum hypoxia, maternal stress - Almost all infants <27 wks GA, almost 0% by 36 wks GA.
Sepsis
Necrotizing Enterocolitis
Intracranial Hemorrhage (Uncontrolled delivery/trauma, neonatal HTN)
Ischemic Cerebral Damage
Immature Metabolism (prolonged drug effects)
Hypoglycemia
Hyperbilirubinemia
Is there any success treating PTL with antibiotics?
Some success preventing preterm labor with antibiotic treatment.
!! NO current recommendations for routine screening and treatment for asymptomatic infections.
How is PTL treated with breech presentations?
C-section is safer
Should you avoid maternal pushing against an incomplete cervix?
Yes!
What does tocolytic therapy do?
Attempts to stop or slow contractions to avoid PTL.
Is long-term tocolytic therapy proven to prolong gestation or reduce neonatal morbidity?
NO!
What is tocolytic therapy used for mainly?
Used for short-term (<48 hrs)
to permit corticosteroid treatment to aid fetal lung maturation
allow transfer to a facility with appropriate NICU facilities.
Tocolytic Therapy: ethanol
Inhibits release of antidiuretic hormone and oxytocin.
Possible direct effect on myometrium or interference with prostaglandins.
IV bolus and maintenance infusion over total of 12 hr.
Significant risk of intoxication, loss of consciousness and aspiration.
No longer used d/t side effects and superior drug availability.
Tocolytic Therapy: Methylxanthines (relatively weak bronchodilators)
Aminophylline
Phosphodiesterase – increase intracellular cAMP uterine muscle relaxation.
Narrow therapeutic margin and frequent toxic side effects limit clinical use.
Tocolytic Therapy: Calcium Channel Blockers
Nifedipine
Myometrium contractility related to free calcium concentration: dec.Ca2+ dec. contractility.
Maternal side effects
Hypotension, tachycardia, dizziness, palpitations
Facial flushing
Vasodilation, peripheral edema
Myocardial depression, conduction defects
Hepatic dysfunction
Postpartum hemorrhage
Fetal side effects
Decreased UBF fetal hypoxemia and fetal acidosis
Patient may be more prone to cardiac depressant effect of volatile agents.
May increase risk of postpartum hemorrhage due to uterine atony refractory to oxytocin and prostaglandin F-α2
Which tocolytic agent may make the patient more prone to the cardiac depressive effect of volatile anesthetics?
calcium channel blockers