Diabetes Flashcards
historical significance of DM in pregnancy
-Before insulin in 1921< 50% of diabetic pts delivered live fetuses
-By 1974, >90% survived
epidemiology of DM
-7% of pregnancies are affected by any form of DM
-86% of pts with DM have GDM
gestational diabetes mellitus (GDM)
-Due to physiologic changes in carb and glucose intolerance and RFs
-Physiologic increase in insulin resistance due to human placental lactogen
GDM dx
-Today, all pregnant patients not known or suspected to have PGDM are screened during prenatal care between 24-28 weeks gestational age (GA)
-This is generally accomplished by a 2 step process
first step of testing for GDM
-1 hour glucose challenge test (GCT)
-50 gm glucose load, followed by a venous glucose level
-No absolute cutoff, but under 130-140 mg/dL
-Lower (130-135 mg/dL) thresholds have not proved to be significantly more sensitive
-Fewer false positive results with use of a normal level of 140 mg/dL
-May screen high risk patients with 1 hour GCT at first prenatal visit
-Consider in pts with past OB hx of complications assoc with undx and unmanaged GDM
second step of testing for GDM
-If 1 hour GCT is elevated (certainly >140 mg/dL) -> 3 hour oral glucose tolerance test (OGTT)
-Pt fasts for 8 hrs and a fasting glucose level is drawn
-A 100 gm glucose load is administered
-1, 2 and 3 hour glucose levels are drawn
interpretating 3 hour OGTT
-Either the Carpenter-Coustan or the National Diabetes Data Group conversion may be used, but practitioners should use the same parameters consistently
-dx of GDM is made when a patient has:
->1 abnormal value on 3 hour OGTT
-However, having even 1 abnormal value increases risk of a perinatal complication
normal values for oral glucose tolerance test in pregnancy
dont memorize
Complications of pathological conditions in pregnancy
-When discussing complications of the antepartum and intrapartum courses, we must consider those affecting:
-The parturient
-The fetus
diabetes mellitus: complications of the parturient
-Birth injury- tend to be bigger (shoulders!!)
-Poor wound healing
-HTN disorders of pregnancy
-Postpartum hemorrhage
-Frank DM later in life (50%)
-baby is acting diabetic
birth injury to the parturient
-Due to maneuvers and techniques for reducing shoulder dystocia -> DM pts at risk of traumatic birth injury
-shoulder dystocia- head is out but cant get the rest of the baby -> birth injury to mom and hypoxia
-These include a fourth degree perineal laceration (r.) that extends through the anus and into the rectal mucosa
diabetes mellitus: common fetal complications
-baby is polydipsic -> drink amniotic fluid -> pee -> cycle -> increase in fluid -> baby is floating around and displaces!
-Spontaneous abortion
-Congenital anomalies
-!Macrosomia
-!Polyhydramnios
-!Shoulder dystocia
-!Erb’s palsy- injury to brachial plexus
-Birth trauma
-Neurological injury
-Neonatal hypoglycemia
-Respiratory distress syndrome
-Death
spontaneous abortion
-risk of spontaneous loss in any pregnancy is ~10%
-same risk in DM (10%)
-risk is higher if DM is poorly controlled at time of pregnancy dx
macrosomia
-fetal wt > 4000-4500
-occurs in about 8% of all live infants
-assoc with worse neonatal outcomes:
-lower 5 minute apgar scores
-higher risk of assisted ventilation
-birth injuries
-mortality
fetal complications of macrosomia: shoulder dystocia
-!MC complication of macrosomia is shoulder dystocia
-shoulder stuck in pubic symphysis
-when you require special maneuver to get baby out OR
-when the shoulder and head deliver are > 1min apart
-Incidence: 0.2-0.3% of all vaginal deliveries
-Shoulder dystocia will result in umbilical cord compression
-Complications due to umbilical cord compression include:
-Acidemia
-Asphyxia
-Neurological injury
-Death
-Complications due to attempts to reduce shoulder dystocia include:
-Erb’s palsy- loss of limb for rest of life
-Humeral fracture
-Clavicular fracture
Polyhydramnios
-amniotic fluid index (AFI) of >25 cm
-Measured via u/s
-May occur in poorly controlled pregestational or GDM due to hyperglycemia-induced sx in the fetus
-Polyuria
-Polydipsia- Amniotic fluid is primarily comprised of fetal urine in the latter half of pregnancy
-Due to the relatively weightless state bc of the increased fluid, this can lead to malpresentation
breech presentation
transverse lie
section
neonatal hypoglycemia
-Caused by high circulating fetal insulin levels because of hyperglycemic state due to poorly controlled maternal DM
-After delivery, w/o maternal hyperglycemia and w/o careful neonatal care, hypoglycemia may result
white classification of DM in pregnancy
dont memorize
-class A is GDM
-everything else is DM before pregnancy
monitoring of glycemic control
-1 or 2 hour postprandial glucose values
-1 hour postprandial: <140
-2 hour postprandial: <120 mg/dL
-If desired, may follow fasting values as well (<92 mg/dL)
-Initially, follow fingerstick glucose measurements 4x/day
-May individualize, but usually ongoing surveillance requires at least 2 readings daily
-review findings weekly
38 year old gravida 3, para 2002 is gx with GDM at 26 wks GA. What 1 hour postprandial fingerstick glucose measurement would be most appropriate
<80
-<100
-<120
-<140!!!!!!!!
management of GDM
-begin with diet
-refer to dietician for nutritional counseling
-a diet that yields best perinatal outcomes is unknown:
-increase daily caloric intake by 300 kcal/day in 2nd and 3rd trimesters
-33-40% carbohydrates- Complex carbohydrates are preferred
-40% fat
-20% protein
-3 meals/day
-2 snacks/day
-exercise: moderate intensity aerobic exercise for 30mins per day at least 5 days per week
-!!Insulin continues to be the pharmacotherapy recommended by the American Diabetes Association for management of hyperglycemia in gravidas with GDM when diet and exercise alone are insufficient (expensive and painful)
-Oral agents were found to be effective and safe in 2000, but have not yet been approved for this purpose by the FDA
-However, they are very commonly used in pregnancy
management of GDM: use of insulin
-Indicated when blood glucose measurement is consistently elevated
-Fasting: >95 mg/dL
-1 hour postprandial: >140 mg/dL
-2 hour postprandial: >120 mg/dL
use of oral agents in the management of GDM: glyburide
-A sulfonylurea that stimulates pancreatic beta cell ATP channel receptors to release insulin
-Does not cross the placenta significantly
-Evidence has suggested an increased risk of fetal macrosomia and in hypoglycemia compared with insulin
use of oral agents in the management of GDM: metformin
-a biguanide that inhibits hepatic gluconeogenesis and glucose absorption
-stimulates glucose uptake and utilization in peripheral tissues
-crosses the placenta -> uncertainty persists about long-term effects on children treated in utero with metformin
-dosage:
-500 mg PO QHS x 1 week, then
-500 mg PO BID
-Titrate as needed
-Maximum dose: 2000-3000 mg in divided doses daily
-26-46% of pts taking metformin will eventually require insulin during pregnancy
-Metformin may be used as an alternative medication in patients who cannot or will not use insulin, or cannot afford insulin
-Thus, while metformin can be and is used to manage GDM, patients do need to be aware that:
-Metformin is generally not considered to be superior to insulin
-The potential is currently unknown for long-term sequelae on children exposed to metformin
fetal assessment in pts with GDM
-in pts with POORLY controlled GDM beginning at 32 weeks, or earlier, if indicated
-NO recommendation for testing in patients with well controlled GDM managed by diet alone
intrapartum care of pts with GDM
-dont need to know
-past 41 weeks- placenta calcifies and gets old -> not good for baby
intrapartum and postpartum concerns with the patient with GDM
-Discuss risks and benefits of prophylactic C-section for pts with estimated fetal weight (EFW) of at least 4,500 gm
-Screen for DM at 4-12 weeks postpartum w/ fasting plasma glucose OR
-Fasting venous glucose followed by 2 hour, 75 gm oral glucose tolerance test (OGTT)
which is the most severe intrapartum complication of GDM
-polyhydraminos
-maternal hyperglycemia
-shoulder dystocia!!!!!!!!!!
-postdates gestations
