Diabetes

Question 1

how is gdm diagnosed?

Answer 1

50 g glucose load non fasting -> 1 hr serum (screening) at 24-28 weeks unless high risk

100 g 3 hour test -> C/C 95/180/155/140 or NDD: 105/190/165/145

Question 2

why treat GDM?

Answer 2

mixed results from large trials but in general benefit of reduced pre-eclampsia, macrosomia, and shoulder dystocia

Question 3

how to monitor blood glucose in pregnancy?

Answer 3

fasting (correlated with neonatal fat index), and postprandial (correlated with lower incidence of LGA, lower cesarean delivery rate)

goal fasting < 95, 1 hr < 140, 2 hr < 120

Question 4

what lifestyle modifications for GDM?

Answer 4

distrubution of calories: 33-40% carbs, 40% protein, 20% fat

cal requirements:
30 kcal/kg/day (2200-2400)
20 kcal/kg/day for BMI > 30

30 m x 5 d/week moderate aerobic exercise = gold standard
small walks recommended if not

Question 5

what types of insulin?

Answer 5

NPH mainstay; but longer acting glargine and detemir more frequently used.

short acting insulin (lispro/aspart) should be used over regular insulin due to quick action.

Question 6

how does metformin compare to insulin?

Answer 6

no established benefit of metformin with regards to CD rates, macrosomia, neonatal hypoglycemia. Does cross placenta, and long term metabolic effects unknown.

reasonable to offer if patient declines insulin, unable to safely administer insulin, cannot afford insulin.

start 500 mg daily; then BID. Then increase to max dose 2500 to 3000 mg

Question 7

glyburide vs metformin/insulin?

Answer 7

outcomes not as good as insulin.

appears in some trial inferior to metformin.

Question 8

White’s classificaiton of DM

Answer 8

A1- pregnancy, diet controlled
A2- pregnancy, insulin controlled

B- > 20 years at dx, < 10 years with dz
C -> 10-20 yrs at dx, 10-20 yrs with dz
D -> < 10 yrs at dx, > 20 yrs with dz

F - nephropathy
H - heart disease
R - retinopathy

Question 9

fetal surveillance?

Answer 9

in poorly controlled DM - 32 weeks

Question 10

fetal risks?

Answer 10

pre-gestational DM:

• still birth
• fetal anomalies (2-6x; 38% cardiac (5x), 15% MSK, CNS 10% (10x), caudal regression rare)
• SAB
• macrosomia (40%)

GDM + pregestational
- LGA/macrosomia

Question 11

neonatal risks with DM?

Answer 11

• hypoglycemia, hypocalcemia, hypothermia (low GCT)

- polycythemia, hyperbilirubinemia, RDS

Question 12

maternal risks of GDM

Answer 12

-pre-x, retinopathy, inc CD, DKA (10% in pre-gestational DM)

Question 13

after delivery?

Answer 13

4-12 weeks 2 hr gtt; then q1-3 hrs

Question 14

delivery?

Answer 14

A1GDM- 39 to 40w6d
A2: 39w0d to 39w6d (well controlled)
A2 if poorly controlled: 37-38w6d
Pregestational: 39-40 weeks if well controlled; 36-38 weeks if not well controlled

Question 15

what are baseline labs for pre-gestational DM?

Answer 15

HA1c, Cr, TSH, EKG. eval optho, dietician at least.

Question 16

when should delivery happen?

Answer 16

Early delivery (360/7 weeks to 38 6/7 weeks of gestation, or even earlier) maybe indicated in some patients with vasculopathy, nephrop-athy, poor glucose control, or a prior stillbirth

well-controlled diabetes with no othercomorbidities may be managed expectantly to 39 0/7 weeksto 39 6/7 weeks of gestation as long as antenatal testingremains reassuring

Question 17

how many pts initially tx’d with metformin and glyburide for GDM will require insulin?

Answer 17

metformin: 46%
glyburide: 18%

Question 18

intrapartum glucose management?

Answer 18

no hard line cut off - at most BG 140. start IV insulin at 0.25 to 0.5 u/hr