Prematur

Preterm Neonate : Whose birth occurs through the end of the last day of the 37 week following onset of the last menstrual period.

Can be categorized by birth weight:

LBW (low birth weight) = infant < 2500 g at birth

VLBW (very low birth weight) = infant < 1500 g at birth

ELBW (extremely low birth weight) = infant < 1000 g at birth

‘Micropremie’ if infant < 750 g at birth

Etiology

Low socioeconomic status (SES)

· Family income

· Educational level

· Residency

· Sosial class

· Occupation

Women < 16 or >36

Maternal activity

· Long periods of standing

· Physical stress

Acute or chronic maternal illness

Multiple gestation birth

Prior poor births outcome

Obstetric factors

· Uterine malformation

· Uterine trauma

· Placenta previa

· Abruptio placenta

· Hypertensive disorder

Fetal condition

· Nonreassuring testing

· IUGR

· Severe hydrops

Inadvertent early delivery because of incorrect estimation of gestational age

Problems of prematurity

Respiratory

· Prenatal depression due to poor adaptation to air breathing

· Respiratory distress syndrome

· Apnea due to immaturity in mechanisms controlling breathing

· Chronic lung disease: bronchopulmonary dysplasia, and chronic pulmonary insufficiency of prematurity

Neurologic

· Perinatal depression

· Intracranial hemorrhage

Cardiovascular

· Hypotension due to: hypovolemia, cardiac dysfunction, vasodilatation due to sepsis

· Patent ductus arteriosus (PDA)

· Problems of prematurity

Hematologic

· Anemia

· Hyperbilirubinemia

Nutritional

Gastrointestinal, single greatest risk factor for necrotizing enterocolitis, reflux

· Clinical Findings: Necrotizing enterocolitis

· Non-specific: feeding intolerance, abdominal distension, occult blood (stool)

· GI: abdominal distension + tenderness; abdominal wall edema, decrease/- bowel sound, bloody stool, greenish NG aspirate

· General: thermal instability, apnea, persistent acidosis, decrease platelets, decrease Hct, decrease neutrophils, decrease BP, decrease urine output, shock

· Metabolic problems: glucose and calcium metabolism

Renal: immature kidney — low GFR — inability to handle water, solute, and acids loads; fluid and electrolyte management

Temperature regulation

Immunologic: deficiency of both humoral and cellular response

Ophthalmologic: rotinopaty of prematurity in

infant <32 weeks or < 1500 g birth weight

Management of the premature infant

Immediate postnatal management

· Delivery in an appropriate equipped and staffed hospital

· Resuscitation and stabilization

Neonatal management

· Thermal regulation

· Oxygen therapy and assisted ventilation

· PDA with birth weight >1000 g usually requires only conservative management:

· adequate oxygenation

ü fluid restriction

ü possibly intermittent

ü diuresis

· Fluid and electrolite therapy — must account for potentially high IWL

· Nutrition — mother’s milk is the optimal primary source of enteral nutrition

· Hyperbilirubinemia – phototherapy, exchange transfusion

· Infection : broad-spectrum antibiotics should be begun when suspicion is strong

· Immunization: HBV, DPT, polio, multivalent pneumococcal, and HIB are given full doses based on their chronologic age (i.e. weeks after birth), not postconceptional age

o If the infant hospitalized at the appropriate chronologic age (usually at 2, 4, and 6 months)

o acellular DPT

o multivalent pneumocaccal are given

o HIB

o Pertussis is contraindicated in infant with possible or documented evolving neurologic disorders

o Oral polio vaccine should not be given

o Administer inactivated polio vaccine (IPV)

o Mothers with HBsAg (+) : resieve Hepatitis B immunoglobulin within 12 hours of birth (always within the 1^st month of life)

o Mothers with HBsAg (-) : optimal timing for HBV with birth weight < 2 kg is not clear. 1^st vaccination for birth weight < 2 kg should be delayed until just before hospital discharge if weight 2 kg or more, or until approximately 2 months.

o between 32 and 35 week with: plans for day care during RSV season, smoker in the household, other young children in the household

o chronic lung disease : Immunization should be given at least 48 hours to discharge so that any febrile response will occur in the hospital

Long-term problems of prematurity

Developmental disability

· Major handicaps (cerebral palsy, mental retardation)

· Sensory impairments (hearing loss, visual impairment)

· Minimal cerebral dysfunction (language disorder, learning disability, hyperactivity)

Retinopaty of prematurity

Chronic lung disease

Poor growth

Increased rates of postneonatal illness and rehospitalization

Increased frequency of congenital anomalies