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Infant of diabetic mother (IDM)Women with diabetes in pregnancy (Type 1, Type 2, and gestational) are all at increased risk for adverse pregnancy outcomes.
Adequate glycemic control before and during pregnancy is crucial for improving outcome.
Most infants born to diabetic mothers are large for gestational age.
If the diabetes is complicated by vascular disease, infants may have growth restriction, especially those born after 37 wk gestation.
The neonatal mortality rate is over 5 times that of infants of non diabetic mothers
Problems of Infants of Diabetic Mothers
Birth traumaBirth asphyxiaHypoglycemiaHypocalcemiaHypomagnesemiaHyperbilirubinemiaSurfactant deficiency–related respiratory distress syndrome (hyaline membrane disease)PolycythemiaRenal vein thrombosisCardiac septal hypertrophy and myocardiopathyCongenital malformationsDiabetic mothers have a high incidence of;
polyhydramniospreeclampsia
pyelonephritis
preterm labor
chronic hypertension
High fetal mortality rate at all gestational ages, especially after 32 wk
Pathophysiology
Maternal hyperglycemia causes fetal hyperglycemia, and increased the fetal pancreatic response leads to fetal hyperinsulinemia;
Fetal hyperinsulinemia and hyperglycemia cause increased hepatic glucose uptake and glycogen synthesis, accelerated lipogenesis, and protein synthesis .
Related pathologic findings are hypertrophy and hyperplasia of the pancreatic β islet cells, increased weight of the placenta and infant organs, myocardial hypertrophy, except for the brain.
Hyperinsulinism and hyperglycemia produce fetal acidosis, which may result in an increased rate of stillbirth.
Separation of the placenta at birth suddenly interrupts glucose infusion into the neonate without a proportional effect on the hyperinsulinism, and hypoglycemia and poor lipolysis develop during the 1st hr after birth
CLINICAL MANIFESTATIONS
Infants tend to be large and plump as a result of increased body fat and big viscera.They have puffy, plethoric facies.
These infants may be of normal or low birth-weight, particularly if delivered before term or the mother has associated vascular disease
HYPOGLYCEMIA
Develops in 25–50% of infants of diabetic mothersOccurs in 15–25% of infants of gestational diabetes mothers, and only small percentage of these infants become symptomatic.
The nadir in an infant's blood glucose concentration is usually reached between 1 - 3 hr after birth; and spontaneous recovery may begin by 4–6 hr after birth.
The infants tend to be jumpy, tremulous, and hyper-excitable during the 1st 3 days of life, although hypotonia, lethargy, and poor sucking may also occur.
Tachypnea
Develops in many infants of diabetic mothers during the 1st 2 days of life.Infants of diabetic mothers have a higher incidence of respiratory distress syndrome may be related to the antagonistic effect of insulin on stimulation of surfactant synthesis by cortisol.
Cardiomegaly
Cardiomegaly is common in 30% of IDM
Congenital heart disease is more common in infants of diabetic mothers.
Heart failure occurs in 5–10% of infants of diabetic mothers.
Asymmetric septal hypertrophy may occur, and inotropic agents worsen the obstruction and so are contraindicated.
Birth trauma is also a common sequel of fetal macrosomia.
Neurologic development and ossification centers; tend to be immature and correlate with brain size (which is not increased) and gestational age rather than total body weight.Hyperbilirubinemia, polycythemia, and renal vein thrombosis; are of increased incidence, and the latter should be suspected in infants with a flank mass, hematuria, and thrombocytopenia.
Congenital anomalies; increased incidence of
The incidence of congenital anomalies is (3X)Cardiac malformations (VSD,ASD,TGA,coarctation of the aorta, others)
lumbosacral agenes
Neural tube defects
Hydronephrosis, other renal anomalies
TREATMENT:
Treatment should be initiated before birth by frequent prenatal evaluation of all pregnant women with overt or gestational diabetes, and by planning the delivery of these infants in hospitals where expert obstetric and pediatric care is available.Preconception glucose control reduces the risk of anomalies and other adverse outcomes, and glucose control during labor reduces the incidence of neonatal hypoglycemia.
Regardless of size, all infants of diabetic mothers should initially receive intensive care.
Hypoglycemia is defined; plasma glucose concentrations of 30 to 45 mg/dL (25 to 40 mg/dL in whole blood) in term infants.
The best treatment of mild, transient neonatal low glucose concentrations is early feeding, whether the neonate is an IDM or not.
A plasma or blood glucose level of less than 20 or 25 mg/dL, respectively, requires intravenous glucose administration unless the infant readily takes a good feeding and remains normoglycemic.
Asymptomatic infants should have a blood glucose determination within 1 hr of birth and then every hour for the next 6–8 hr;
If clinically well and normo-glycemic, oral or gavage feeding with breast milk or formula should be started as soon as possible and continued at 3 hr intervals. If any question arises about an infant's ability to tolerate oral feeding, the feeding should be discontinued and glucose given by peripheral intravenous infusion at a rate of 4–8 mg/kg/min.
Hypoglycemia should be treated, even in asymptomatic infants, by frequent feeding and/or intravenous infusion of glucose.
Bolus injections of hypertonic glucose should be avoided because they may cause further hyperinsulinemia and potentially produce rebound hypoglycemia
HYPOCALCEMIA
Calcium concentration in the immediate newborn period decreases in all newborn infants.
Hypocalcemia is usually defined as a total serum concentration less than 7 mg/dL.
Clinical Findings
The clinical signs of hypocalcemia and hypocalcemic tetany include a high-pitched cry, jitteriness, tremulousness, and seizures.Apnea,muscle twitching ,laryngospasm.
Chvostek sign :facial muscle spasm when the side of the face (over the 7th nerve) is tapped.
Trousseau sign :carpopedal spasm induced by partial inflation of a blood pressure cuff
The last 2 signs are rare in the immediate newborn period.
Hypocalcemia tends to occur at two different times in the neonatal period:
Early-onset hypocalcaemia; occurs in the first 2 days of life and is associated with prematurity, maternal diabetes, asphyxia, and, rarely maternal hypoparathyroidism.Late-onset hypocalcemia; occurs at approximately 7–10 days and is observed in;
Infants receiving modified cow's milk rather than infant formula (high phosphorus intake).
In infants with hypoparathyroidism
In infants with hypomagnesemia.
Mothers with vitamin D deficiency .
Treatment
A. ORAL CALCIUM THERAPY:The oral administration of calcium salts is a preferred method of treatment for chronic forms of hypocalcemia resulting from hypoparathyroidism but is rarely used in early-onset hypocalcemia.
Calcium in the form of calcium gluconate can be given as a diluted solution or added to formula feedings several times a day.
If a 10% solution of calcium gluconate is used, the dose is 5–10 mL/kg/day given in divided doses, every 4 - 6 hours.
B. intravenous calcium therapy:
Intravenous calcium therapy is usually needed for infants with symptomatic hypocalcemia
A number of precautions must be observed when calcium gluconate is given intravenously, as the infusion must be given slowly so that there is no sudden increase in calcium concentration of blood entering the right atrium, which could cause severe bradycardia and even cardiac arrest.
Hypomagnesaemia
Hypomagnesemia occurs when serum magnesium levels fall below 1.5 mg/dL (0.62 mmol/L).
It occurs during exchange transfusion with citrated blood, which is low in magnesium because of binding by citrate, approximately 10 days are required for return to normal.
Hypomagnesemia should also be suspected in any patient with tetany not responding to calcium therapy.
Immediate treatment consists of intramuscular injection of magnesium sulfate. For newborn infants, 25-50 mg/kg/dose every 8 hr for 3-4 doses usually suffices.
