COMPLICATIONS OF PREMATURITY

Mona Khattab, MD

Neonatal-Perinatal Fellow

Yale University Children’s Hospital

I am not just a “Small” baby… I am a “Preterm” baby….

I am a “Unique Baby”… with “Unique Problems”!!

Definition-Magnitude of Problem

Prematurity < 37 completed weeks

Accounts for 1/3 of infant deaths in USA, 45% cerebral palsy, 35% vision impairment, and 25% cognitive or hearing impairment.

Risk of complications increases with increasing immaturity

Classification based upon GA:

oLate preterm birth — GA between 34 and < 37 weeks

oVery preterm birth — GA < 32 weeks

oExtremely preterm birth — GA ≤ 28 weeks

Classification by BW

oLow birth weight (LBW) < 2500 g

oVery low birth weight (VLBW) < 1500 g

oExtremely low birth weight (ELBW) < 1000 g

YOUR TURN

Short-term complications

Long-term complications

Proper stabilization in the DR is important to reduce risk of short-term complications decrease long term complications.

SHORT-TERM COMPLICATIONS

o Hypothermiao Respiratory abnormalities: RDS, pneumothoraxo Cardiovascular abnormalities: PDA, hypotensiono Central nervous system: IVH, PVLo Metabolic: Hypo/ hyperglycemia,

hypo/hypernatremia, hypo/hyperkalemiao Gastrointestinal: NEC, perforationso Immune system: Sepsis, meningitis, UTIo Eyes: Retinopathy of prematurity

EPIDEMIOLOGY

NICHD 8515 VLBW study:oRespiratory distress: 93%oRetinopathy of prematurity: 59%oPatent ductus arteriosus: 46%oBronchopulmonary dysplasia: 42%oLate-onset sepsis: 36%oNecrotizing enterocolitis: 11%oGrade III and Grade IV IVH: 7 and 9%oPeriventricular leukomalacia: 3%

HYPOTHERMIA

o Relatively large body surface area and inability to produce enough heat.

o Heat loss by conduction, convection, radiation, and evaporation.

o Sequale: hypoglycemia, acidosis, apnea o Greatest risk for hypothermia immediately

after birth in the delivery room. o Admission temperature is inversely related to

mortality and late-onset sepsis.

Standard care in DR to prevent hypothermiaoMaintain the delivery room temperatureoDrying the baby thoroughly immediately after birthoRemoval of any wet blanketsoUse of prewarmed radiant heaterso Polyethylene/polyurethane body wrap or bags, and polyethylene or stockinet caps) or oExternal heat sources ( skin to skin care and transwarmer mattress)

RESPIRATORY COMPLICATIONS

o RDS: incidence and severity increase with decreasing gestational age.

o Bronchopulmonary dysplasia, CLD, defined as oxygen dependency at 36 weeks postmenstrual age (PMA)

o Apnea of prematurity: 25% of preterm infants. Incidence increases with decreasing gestational age

CARDIOVASCULAR COMPLICATIONS

PDA: Symptomatic 30% VLBW

Shunts blood flow from left-to-rightincrease pulmonary flow and decreased systemic circulation.

Severity depends upon size and response of the heart and lungs.oSignificant shunting hypotension, oligurea, apnea, respiratory distress, or heart failure

CARDIOVASCULAR COMPLICATIONS

Systemic hypotension : in the immediate postnatal period significant morbidity (IVH) and mortality.oVolume expansion: crystalloid (eg, normal saline) and colloid (eg, fresh frozen plasma) oInotropic therapy: (dopamine, epinephrine)oSystemic glucocorticoid therapy: refractory hypotension or those who required high dose inotropic therapy (adverse effects: intestinal perforation and long-term poor neurodevelopment outcome (eg, cerebral palsy)

CNS COMPLICATIONS

Intraventricular hemorrhage: in the fragile germinal matrix and increases with decreasing BWbirth. Incidence of severe IVH (Grades III and IV) 12-15%in VLBW Preventive measures: prompt and appropriate resuscitation, avoid hemodynamic instability and conditions that impair cerebral autoregulation (eg, hypoxia, hypercarbia, hyperoxia, and hypocarbia).

METABOLIC COMPLICATIONS

Glucose abnormalities:

hypoglycemia or hyperglycemia Blood glucose concentration should be monitored routinely starting immediately after birth and continued until feedings are well established and glucose values have normalized

“Other metabolic abnormalities will be discussed separately”

GI COMPLICATIONS

Necrotizing enterocolitis (NEC):

2-10 percent of VLBW infants. associated with increase in mortality.

Survivors are at increased risk for growth delay and neurodevelopmental disabilities.

INFECTION

Classification:o Early onset sepsiso Late-onset sepsis

Risk factors for infection: Prolonged intubation, BPD, prolonged intravascular access, PDA, and NEC.

Neonatal sepsis is associated with increased likelihood of poor neurodevelopmental outcome and growth impairment.

EYE

Retinopathy of prematurity (ROP):oDevelopmental vascular proliferative disorder occurs in the incompletely vascularized retina of premature infants. oIncidence & severity of ROP increases with decreasing gestational age or birth weight. oTypically begins about 34 weeks(PMA), but may be seen as early as 30 to 32 weeks. oNext to cortical blindness, ROP is the most common cause of childhood blindness in the USA.

Pathogenesis of ROP

Hypotension, hypoxia, or hyperoxia, with free radical formation, injures newly developing blood vessels and disrupts normal angiogenesis neovascularization retinal edema, hemorrhage and abnormal fibrovascular tissue development.

LONG-TERM COMPLICATIONS

o Neurodevelopmental outcome: Impaired cognitive skills

o Motor deficits including mild fine or gross motor delay, and cerebral palsy

o Sensory impairment including vision and hearing losses

o Behavioral and psychological problemso Poor growth compared to those born full-termo Impairment of lung function

EFFECT ON ADULT HEALTH

oInsulin resistance oHypertension and vascular abnormalitiesoReproduction: Prematurity has been associated with decrease reproduction in adulthood.

THANK YOU