Prematurity and IUGR

Download more documents and slide shows on The Medical Post [ www.themedicalpost.net ]

Dr. Kalpana MallaMD Pediatrics

Manipal Teaching Hospital

• Preterm – born before 37 completed weeks of gestation• IUGR - birth weight is <10TH CENTILE FOR GESTATIONAL AGE or > 2 SDs below mean for GA.

Types of IUGR

• Symmetric IUGR: weight,length and head circumference are all below the 10 th percentile. (33 % of IUGR Infants)

• Asymmetric IUGR: weight is below the 10 th percentile and head circumference and length are preserved. (55 % IUGR)

• Combined type IUGR: Infant may have skeletal shortening, some reduction of soft tissue mass. (12 % of IUGR)

Characteristics of IUGRSymmetric (chronic)• Early onset - Due to 1. intrinsic cong infection or chromosomal genetic

defects 2. Extrinsic factor (early gestational life) – maternal

malnutrition, alcohol, smoking• Normal ponderal index• Brain symmetrical to body• Decreased growth potentialExamples - Genetic causes, chromosomal - TORCH infections - Anomalad Syndromes

Characteristics of IUGR

Asymmetric (acute)• Late onset- Environmental factors• Brain sparing• Has better prognosis Examples• Hypoxia• Preeclampsia (PIH, PET)• Chronic hypertension

Ponderal Index

• Way of characterizing the relationship of height to mass for an individual.

• PI = 1000 x

• Typical values are 20 to 25.• PI is normal in symmetric IUGR.• PI is low in asymmetric IUGR.

Mass (kgs) Height (cms)

3

Causes of Preterm BirthFETAL • Fetal distress• Multiple gestation• Erythroblastosis• Nonimmune hydrops

PLACENTAL • Placental dysfunction• Placenta previa• Abruptio placentae

Causes of Preterm Birth

UTERINE • Bicornuate uterus• Incompetent cervix (premature

dilatation)

Causes of Preterm Birth

MATERNAL • Preeclampsia• Chronic medical illness (e.g.,

cyanotic heart disease, renal disease)

• Infection (e.g., Listeria monocytogenes, group B streptococcus, urinary tract infection, bacterial vaginosis, chorioamnionitis)

• Drug abuse (e.g.cocaine)

Causes of Preterm Birth

OTHER • Premature rupture of membranes• Polyhydramnios• Trauma

Factors Associated with IUGR

FETAL • Chromosomal disorders • Chronic fetal infections (e.g.,

cytomegalic inclusion disease, congenital rubella, syphilis)

• Congenital anomalies–syndrome complexes

• Irradiation

Factors Associated with IUGR

FETAL • Multiple gestation• Pancreatic hypoplasia• Insulin deficiency• Insulin-like growth factor type I

deficiency

Factors Associated with IUGR

PLACENTAL FACTORS

• Placental insufficiency ( most imp in 3rd trimester) • Villous placentitis (bacterial, viral,

parasitic)• Infarction• Tumor (chorioangioma, hydatidiform

mole)• Premature placental separation• Small Placenta • Twin transfusion syndrome

Factors Associated with IUGR

Maternal Factors:• Decrease Uteroplacental blood flow:

- Pre eclampsia / eclampsia- chronic renovascular disease- Chronic hypertension

• Maternal malnutrition, & chronic illness• Multiple pregnancy• Drugs

- Cigarettes, alcohol, heroin, cocaine- Teratogens, antimetabolites and

therapeutic agents warfarin, phenytoin

Factors Associated with IUGR

• Maternal hypoxemia- Hemoglobinopathies - High altitudes

• Others- Short stature- Younger or older age (<15 and >45)- Low socioeconomic class- Primiparity- Grand multiparity- Low pregnancy weight- Previous h/o preterm IUGR baby

• Small but plump• Red or very pimk• Length <50cm• HC<35cm• Lanugo hair,vernix ++• Skin –shiny

transparent thin,edematous

• Ears,breast,genitalia –premature

• Hypotonic (floppy

• Wasted • White or pale pink• Length ≥ 50 cm• HC≥ 35 cm• Thick,dark hair• Skin – dry,loose thick• Ears,breast,genitalia –

mature• Good muscle tone

IUGR

• Heads are disproportionately large for their trunks and extremities

• Facial appearance has been likened to that of a “wizened old man”.

Problems of IUGR (SGA) Infants

• Hypoxia - Perinatal asphyxia

- Persistent pulmonary hypertension - Meconium aspiration

• Thermoregulation- Hypothermia due to diminished subcutaneous fat and elevated surface/volume ratio

Problems of IUGR (SGA) Infants

• Metabolic - Hypoglycemia

- result from inadequate glycogen stores.- diminished gluconeogenesis.- increased BMR

- Glucose needs of hypoxia - Hypothermia - Large brain

- Hypocalcemia- due to high serum glucagon level, which stimulate calcitonin excretion

Problems of IUGR (SGA) Infants

• Hematologic - hyperviscosity and polycythemia due to increase erythropoietin level sec. to hypoxia

• Immunologic- IUGR have increased protein catabolism and decreased in protein, prealbumin and immunoglobulins, which decreased humoral and cellular immunity.

Problems of IUGR (SGA) Infants

• Skeletal: Decreased ossification of endochondral & membranous cartilage.

• Malformations: Increased incidence of Cong.malformations.

Problems of IUGR (SGA) Infants

Dysmorphology• Syndrome anomalads• chromosomal-genetic disorders• Oligohydramnios-induced

deformations• TORCH infection• Pulmonary hemorrhage

Problems with Premature Infants

RESPIRATORY • Respiratory distress syndrome

(hyaline membrane disease) • Bronchopulmonary dysplasia• Pneumothorax, pneumomediastinum;

interstitial emphysema• Congenital pneumonia• Pulmonary hypoplasia• Pulmonary hemorrhage• Apnea

Problems with Premature Infants

CARDIOVASCULAR • Patent ductus arteriosus • Hypotension• Hypertension• Bradycardia (with apnea)• Congenital malformations

Problems with Premature Infants

HEMATOLOGIC • Anemia (early or late onset)• Hyperbilirubinemia–indirect • Subcutaneous, organ (liver, adrenal)

hemorrhage • Disseminated intravascular

coagulopathy• Vitamin K deficiency

Problems with Premature Infants

GASTROINTESTINAL • Poor gastrointestinal function–poor

motility • Necrotizing enterocolitis• Congenital anomalies producing

polyhydramnios• Spontaneous gastrointestinal isolated

perforation

Problems with Premature Infants

METABOLIC-ENDOCRINE • Hypocalcemia • Hypoglycemia • Hyperglycemia • Late metabolic acidosis

Problems with Premature Infants

RENAL • Dyselectrolytemia – hyponatremia,

hypernatremia,hyperkalemia • Renal tubular acidosis

Problems with Premature Infants

CENTRAL NERVOUS SYSTEM • Intraventricular hemorrhage • Periventricular leukomalacia• Hypoxic-ischemic encephalopathy• Seizures• Retinopathy of prematurity• Deafness• Hypotonia

Problems with Premature Infants

• Congenital malformations• Kernicterus (bilirubin

encephalopathy)• Drug (narcotic) withdrawal

OTHER • Infections (congenital, perinatal,

nosocomial: bacterial, viral, fungal, protozoal)

Management of IUGR

• Delivery and Resuscitation • Hypoglycemia

- close monitoring of blood glucose- early treatment ( IV dextrose, early feeding )

• Hematological Disorder - Hct to detect polycythemia• Congenital infection

- TORCH titer screening- Viral cx of urine, nasopharynx- Head CT to r/o calcification

Management of IUGR

• Genetic anomalies- screening- chromosomal analysis

• Others- serum calcium to r/o hypocalcemia- Mx - meconium aspiration

Management-PRETERM /LBW DELIVERY ROOM CARE

• Warmth and drying• Resuscitation / Respiratory support

• Oxygen blow-by• Bag-and-mask ventilation• Endotracheal intubation and ventilation

• Exogenous surfactant• Nasal CPAP if required

• Transfer to NICU in transport incubator

CRITERIA FOR NICU ADMISSION OF LBW BABIES *

• Gestational age <34 weeks• Birth weight < 1800 g• SGA with birth weight <3rd percentile • Any sick neonate, irrespective of BW

and gestational age

* Recommendations of the National Neonatology Forum

NICU CARE

• Temperature control• Respiratory support• Fluids and electrolytes• Nutritional support• Infection control• Cardiovascular support• Others- Skin care, Hyperbilirubinemia• Suplement

1. TEMPERATURE CONTROL• Aim: a) Maintaining temperature b) Prevent cold stress c) Reduce insensible water loss• Methods:

– Radiant warmer (290 C-310 C)– Pre warmed incubator ( 320C- 350C)

– Warm room – ( 210 C) – Heat shield– Warm clothing-cap, socks– KMC– Bath postponed

KANGAROO MOTHER CARE• Benefits

–Thermoregulation–Exclusive breast feeding–Physiologic stability–Decreased incidence of infection– Infant-mother bonding–Cost effective

2. RESPIRATORY SUPPORT

• Free flow oxygen• Ventilatory

support• Surfactant

therapy

3. FLUID REQUIREMENT

Fluid requirements are higher in LBW infants due to–Greater insensible water losses –Faster breathing rates–Decreased ability to concentrate

urine–Greater use of radiant warmers –Greater use of phototherapy units

RATE OF ADMINISTRATION*

Birth weight (g)

Fluid rate (ml/kg/day)

500 - 600 140 - 200

601 - 800 120 - 130

801 - 1000 90 - 110

1000 - 1500 80 - 100

>1500 60 - 80

*on first 2 days of life

RATE OF ADMINISTRATION

• Fluid rate can be increased by 10-20 ml/kg/d to gradually reach 150 ml/kg/d

• Fluid requirements need to be individualized for each baby

• Enteral nutrition has to be considered once the baby is stable

FLUID COMPOSITION & MONITORING

• Dextrose solutions to give 6 -8 mg/kg/min of glucose

• Sodium supplementation from day 2• Frequent monitoring of

• Serum glucose levels• Urine output & specific gravity • Weight (twice daily)• Serum electrolytes (ideally q8h – q12h)

• Physical assessment

4. TOTAL PARENTERAL NUTRITION

• Indications– Infants with BW ≤ 1000 g– Infants with BW ≤ 1500 g, done in

conjunction with slowly advancing enteral nutrition

– Infants with BW 1501-1800 g for whom enteral intake is not expected for > 3 days

TOTAL PARENTERAL NUTRITION

• Glucose : 6 - 8 mg/kg/min• Amino acids : 1.5 - 2 g/kg/d• Lipid : 0.5 - 1 g/kg/d• Sodium : 2 - 4 mEq/kg/d• Potassium : 2 - 3 mEq/kg/d• Chloride : 2 - 4 mEq/kg/d

TOTAL PARENTERAL NUTRITION

• Calcium • Phosphorous• Magnesium • Others:

–Zinc–Copper–Chromium–Selenium–Molybdenum

EARLY ENTERAL NUTRITION

Trophic feeding/ Gut priming Practice of feeding very small amounts

of enteral nourishment to stimulate development of the immature GIT

Adv: Improves GI motility Enhances enzyme maturation Improves mineral absorption Lowers incidence of cholestasis Shortens time to regain birth weight

ENTERAL NUTRITION

• Breast milk or ½ or full strength preterm formula at 10ml/kg/d by intermittent gavage/ continuous nasogastric drip

• Increase by 10-15 ml/kg/d to reach 150ml/kg/d

• Increments not >20 ml/kg/d• IV fluids can be stopped once

120ml/kg/d is reached• On reaching 150ml/kg/d,calorie

density can be increased

FEEDING GUIDELINES

PRETERMS• <1200 g/ <32 wks: IV fluids for first

2-3 days, once stable start gavage feeding

• 1200-1800 g/ 32-34 wks: Start gavage feeding, once vigorous start spoon/ breast feeding

FEEDING GUIDELINES

• >1800 g/ >34 wks: Start breast feeding directly; if trial feed takes>20 mins or intake is less than required, switch to gavage feeding

TERM IUGRs/ SGA• Breast feeding

PRETERM HUMAN MILKAdvantages:

–Higher concentrations of amino acids

–Higher concentrations of essential fatty acids

–Lower renal solute load–Specific bio-active factors provide

immunity–Promotes intestinal maturation

PRETERM HUMAN MILK

Disadvantages:–Low concentrations of Vitamin D,

Ca, P – Inadequate iron

ENTERAL NUTRITION

• Energy : 130 - 175 Kcal/kg/d• Protein :3.4 - 4.2 g/kg/d• Fat :6 - 8 g/kg/d• Na :3 - 7 mEq/kg/d• Cl :3 - 7 mEq/kg/d• K :2 - 3 mEq/kg/d• Ca :100 – 220 mg/kg/d

5. INFECTION CONTROL• LBW infants are at a greater risk of

sepsis • Practices that can prevent/minimize

infections:–Strict adherence to hand-washing–Minimal handling & clustering of

procedures– Barrier nursing–Antibiotics

5. INFECTION CONTROL

–Practices that can prevent/minimize infection:

–Restriction of broad spectrum antibiotics use

–Minimizing duration of mechanical ventilation

–Early initiation of enteral feeds–Central & peripheral venous catheter

care

6.CARDIOVASCULAR SUPPORT

• Blood pressure maintenance with• Fluids • Pressor agents if required

• PDA: –Fluid restriction–Diuretic therapy – Increased ventilatory support– Indomethacin therapy–Surgical ligation

7. SKIN CARE

• Stratum corneum is deficient in preterms• Mature epidermal barrier is established by

2 weeks post natal age• Limited use of adhesives• Frequent repositioning of infant• Use of soft bedding or water mattress• Prophylactic use of emollients is no longer

recommended• Jaundice – early management

8. SUPPLEMENTATION

• Human Milk Fortifiers• Calcium:50-100 mg/kg/d from end of 1st

week to 40 weeks post-conceptional age• Iron:2-2.5 mg/kg/d from 6-8 wks of age till

12 months of age• Vitamins

– Vitamin A(1000U/d) & Vitamin D(400U/d) ,Vit C – 50mg/d from 2 weeks of age

– Vitamin E -15 IU/d for VLBW infants till 37 weeks

Outcome

• Symmetric vs. Asymmetric IUGR- symmetric has poor outcome compare to asymmetric

• Preterm IUGR has high incidence of abnormalities• IUGR with chromosomal disease has 100% incidence

of handicap• Congenital infection has poor outcome - handicap

rate > 50%• IUGR has higher rate of learning disability.

“Long term” Morbidity of IUGR“Long term” Morbidity of IUGRFactors associated with abnormal

outcome ? Microcephaly

Hypoxic ischemic encephalopathy Symptomatic hypoglycemia Symptomatic hyperviscosity

Fetal Origins of Adult Diseases ?Fetal Origins of Adult Diseases ?• Coronary artery disease correlates

inversely with birth weight• Rate of non-insulin dependent diabetes

mellitus is highest in the “thinnest” babies at birth (low ponderal index)

• High serum cholesterol are linked to disproportionate size at birth (body smaller than head)

• Increased rate of hypertension in infants who were thin, short, &/or proportionately small at birth

Sequelae of Low Birth weight

• Mental retardation• Poor school performance• Spasticity• Seizures• Hydrocephalus• Sensorineural injury-Hearing • Short-bowel syndrome• Malabsorption

Sequelae of Low Birth weight

• Visual impairment• Retinopathy of prematurity• Strabismus, myopia• Bronchopulmonary dysplasia, • Bronchospasm• Recurrent pneumonia

Sequelae of Low Birthweight

• Growth failure - Failure to thrive • Gastroesophageal reflux• PEM• Osteopenia, fractures, • Anemia

Follow-up

• Anemia• Retinopathy of prematurity• Hearing screenings• Cholestasis• Stable temperature regulation• Gaining weight on oral feedings• Nutritional support

Follow-up

• Breast-feeding• Appropriate immunizations• Ophthalmologic examination if <27

wk or <1,250?g at birth

Thank youDownload more documents and slide shows on The

Medical Post [ www.themedicalpost.net ]