Antepartum / intrapartum fetal evaluation, operative vaginal delivery, TOLAC, diabetes Flashcards
Effect of mild hypoglycemia on fetal movement
Increases
Contractions required for CST
3 ctx in 10 min last 40-60 sec each
CST outcomes
Neg = no late decels Pos = recurrent lates (>50% of ctx) Equivocal = intermittent late decels
Time for NST
20 min
BPP fetal breathing
30 sec or more within 30 min
BPP fetal movement
Three or more discrete body / limb movements within 30 min
BPP fetal tone
One or more episode of flexion / extension
BPP AFV
One or more pocket 2 x 2 cm or greater
BPP 6/10 preterm
Repeat BPP in 24 hrs
BPP 4/10
Deliver
Even with score 0 on BPP, false positive rate is…
20% (it is 75% for 6/10)
Modified BPP
NST + AFI (>5 cm is normal)
Percent of cerebral palsy cases that occur antepartum vs intrapartum
> 70% vs 4%
Tachysystole
> 5 ctx in 10 min
Common causes of fetal tachycardia
Maternal fever, scopolamine, atropine, hydroxyzine, terbutaline, ritodrine, epinephrine
Rare causes of tachycardia
Fetal hyperthyroidism, anemia, HF, or arrhythmias
Rare causes of fetal bradycardia
Heart block, hypothermia, hypoglycemia, beta blockers, Nubain
Accelerations guarantee…
pH > 7.20
Pathologic fetal acidemia cord blood values
pH < 7.00 and base deficit > 12
Fetal contraindications to operative delivery
Osteogenesis imperfecta, thrombocytopenia, hemophilia
Gestational age for vacuum
34 wga (can do below for forceps)
Mid, low, outlet operative delivery
Mid > +2 station
Low > +2 station and not on pelvic floor
Outlet > +2 and scalp visile at introitus
Late-term vs post-term
41.0 - 41.6 wga vs > 41.6 wga
When to initiate antenatal testing in normal pregnancy
41.0 wga (“may begin testing”)
Prevalence of GDM
7%
Hormones involved in pathology of GDM
Human chorionic somatomammotropin (hPL), progesterone, prolactin, cortisol. placental insullinase (increased clearance)
Lifetime risk of T2DM if GDM present
50%
Criteria for early glucose screening
BMI > 25 + risk factor (inactivity, ethnicity, cHTN, PCOS, first degree relative, hyperlipidemia, hx of GDM, prior BW > 4000 g)
Glucose screening
24-28 wga: 1 hr GTT (50 g glucose load)
NNT to prevent 1 brachial plexus injury by doing C/S for EFW > 4500 g
588
How/when to screen for DM postpartum
6-12 wks postpartum and q3yrs thereafter (prefer 75 g 2 hr GTT)
Definition of diabetic nephropathy (DM-F)
> 400 mg protein in 24 hrs prior to 20 wga
Risks of pregestational DM in the first trimester
SAB, 6-12% risk of congenital malformations (cardiac, skeletal, CNS, or caudal regression)
With HgbA1c = 10%, risk is 20-25%
Risk of IUFD in third trimester with pregestational DM
1%
Rule of 8’s
HgbA1c = 8% -> average BG 180 mg/dL
Each 1% change = +/- 30 mg/dL
Effect of 1 u of short-acting insulin
Lowers BG by about 30 mg/DL and covers 10 g of carbohydrates
Risk of shoulder dystocia with DM vs not
50% increased risk
Fluid deficit in DKA
100 mL/kg
