370 likes | 855 Views
Intrauterine Growth Restriction IUGR. Dana Rivera, M.D. October, 2010. SGA : BW less than population norms < 10 th %-tile OR < 2 standard deviations below the mean (~3 rd %-tile) pathologic or non-pathologic causes. IUGR : BW < expected inhibition of normal growth potential
E N D
Intrauterine Growth RestrictionIUGR Dana Rivera, M.D. October, 2010
SGA: BW less than population norms < 10th %-tile OR < 2 standard deviations below the mean (~3rd %-tile) pathologic or non-pathologic causes IUGR: BW < expected inhibition of normal growth potential implies pathology SGA vs IUGR
True or False? • All SGA infants are IUGR • False • All IUGR infants are SGA • False
- Stage I growth inhibition Fewer cells but normal size - weight, head, length all < 10th percentile Perinatal problems? Higher Lower Growth potential? Higher Lower Symmetric
- Stage II/III growth inhibition Decrease in cell size, less effect on total cell number - weight below 10th percentile,head and length preserved Perinatal problems? Higher Lower Growth potential? Higher Lower Asymmetric
Sex term males 150 gm heavier and 0.9 cm longer than females Parity 1st born infants smaller effect loss after 3rd birth Race, ethnicity, nationality Altitude Denver population growth curves under estimate weights of infants born at sea level Maternal size maternal pre-pregnancy weight and pregnancy weight gain correlate with fetus size What factors affect fetal weight?
Number of fetuses Reduced rate of fetal growth of multiples Small breed embryo transplanted into large breed uterus will grow larger “Maternal constraint”- non-genetic
Insulin Major hormone for in utero growth Produced by fetus Promotes fetal adipose deposition, glycogen stores Hormonal Factors
Etiology- Overlapping Maternal, Fetal, Placenta • Maternal factors • Medical disease (US) • Malnutrition (world-wide) • Multiple pregnancy • Drugs • Hypoxemia • Small stature/ low pre-pregnancy weight • Teen pregnancy • Low SES • Prima gravida • Grand multiparity
Fetal • Genetic • Congenital malformations • Genetic/ chromosomal (trisomies, syndromes) • Cardiovascular disease • Congenital infection • Inborn errors of metabolism
Placenta • placental insufficiency • post dates • anatomic • abnormal insertion • hemangiomas • infarcts • abruption
Case # 1 • A baby is delivered at 36 WGA via repeat C- section • BW- 2 kg • HC- < 10th %tile • Lt- < 10th %tile CMV
Case #1- What if? Toxoplasmosis Rubella
“TORCH” Stigmata • hepatoslpenomegaly • petechiae/ ecchymoses • blueberry muffin rash • vesicles/ mucocutaneous lesions • chorioretinitis/ cataracts/ salt-pepper retinopathy • PPS/PDA • microcephaly/ hydrocephaly • Intracranial calcifications
Diagnosis Algorithm • IUGR yes TORCH stigmata work-up? no
Case # 2 • A baby is delivered via NSVD, no prenatal care, EGA 35 weeks • BW- 1500 gm • HC- < 10th • Lt- <10th Trisomy 13
Case #2- What if? Trisomy 18 Turner syndrome
Diagnosis Algorithm IUGR yes TORCH stigmata work-up? no yes Dysmorphic features work-up? no
Case # 3 • Infant is delivered at 38 weeks to mom who presents with headaches and epigastric pain • BW: 2.1 kg • HC: 50th%tile • Lt: 30th%tile Pre-eclampsia/ HELLP
Case # 3- What if? • Mom with no prenatal care delivers undiagnosed twins at EGA 34 weeks Discordant twins
Case # 3- What if? • An infant is delivered at 42 weeks via c- section due to NRHTs after induction Post dates • - decreased subcutaneous fat • - skin desquamation • - wizened facies • - large AF(diminished membranous bone formation) • - meconium staining
Diagnosis Algorithm IUGR yes TORCH stigmata work-up? no yes Dysmorphic features work-up? no yes Maternal/placental explanation work-up? no
Case # 3- What if? • Infant delivered at EGA 34 weeks to mom with no prenatal care and positive tox screen
Diagnosis Algorithm IUGR yes TORCH stigmata work-up? no yes Dysmorphic features work-up? no yes Maternal/placental explanation work-up? no yes Maternal drug use tox screen no Unknown cause
True or False • IUGR infants are prone to asphyxia • True • Why or why not? • Perinatal hypoxia • Chronic and acute • Increased C/S rate, decreased Apgar, increased resuscitation need
An IUGR infant is at risk for Hypothermia? Hypoglycemia? Or Hypocalcemia? decreased subcutaneous fat, increased surface- volume ratio, decreased heat production decreased glycogen stores/ glycogenolysis/ gluconeogenesis increased metabolic rate deficient catecholamine release Associated with perinatal stress, asphyxia, prematurity
Which lab result(s) would not be associated with IUGR? • WBC 4, S8 & B1 • H & H 11/ 33 • Plt 65 • PT 16 • PTT 56 • Direct bilirubin 4.5 • Neutropenia • Polycythemia • Elevated erythropoietin • Thrombocytopenia • Elevated coags • TORCH
Which CxR is more consistent with IUGR? Increased meconium aspiration Decreased surfactant deficiency
Perinatal problems • Perinatal asphyxia • Hypothermia • Hypoglycemia • Hypocalcemia • Polycythemia, hyperviscosity • Thrombocytopenia • Neutropenia • Elevated coags • Decreased surfactant deficiency • Increased meconium aspiration syndrome • Direct hyperbilirubinemia
Evaluation and Management • Physical exam • Labs - blood sugar - urine shell vial (CMV) - calcium - viral cultures (HSV) - CBC diff/plt - syphilis w/u - bilirubin - tox screen - head ultrasound - chromosomes - total IgM vs specific
Evaluation and Management • Monitor postnatal weight gain/ head growth • needs may exceed 100-120 cal/kg/d • catch- up by 6-12 months • Hypersomatotropism- accelerated growth velocity • ? Safety of aggressive feeding • rapid weight gain may predispose to childhood obesity highest risk for developing type 2 DM
IUGR- Outcome • Neurodevelopment • etiology and adverse event dependent • lower intelligence, learning/ behavioral disorders, neurologic handicaps • symmetric, chromosomal disorders, congenital infections--- poorer outcome • school performance influenced by social class