Neonatal medicine involves medical care for a wide variety of diseases and disorders in newborn infants, ranging from extremely small preterm babies at the edge of viability to healthy infants who are admitted to a typical newborn nursery.
Neonatology was recognized as a medical specialty in the 1960s and 1970s. Key discoveries over the years in neonatology include thermoregulation, intravenous (IV) nutrition, methods of mechanical ventilation, artificial surfactant, and antenatal glucocorticoids for mothers at risk of premature delivery.
Neonatal Definitions and Classifications
Infants are classified according gestational age, birth weight, and growth status.
- extremely preterm: ≤28 weeks
- preterm: 28 weeks to 34 weeks
- late preterm: 34 weeks to ≤36 weeks and 6 days
- early term: ≥37 weeks to ≤38 weeks and 6 days
- term: ≥39 weeks to <42 weeks
- post-term: ≥42 weeks
- extremely low birth weight (ELBW): ≤1000 grams
- very low birth weight (VLBW): ≤1500 grams at birth
- low birth weight (LBW): ≤2500 grams
- small for gestational age (SGA): ≤10th percentile for gestational age
- appropriate for gestational age (AGA): 10th to 90th percentile for gestational age
- large for gestational age (LGA): ≥90th percentile for gestational age
Neonatal Intensive Care Units (NICUs)
Infants are cared for in levels I–IV NICUs to provide appropriate intensity of care while attempting to keep the infant close to home, especially prior to discharge. The American Academy of Pediatrics (AAP) 2004 policy statement defines the levels of care as follows:
- Level I nurseries provide basic newborn care to infants ≥35 weeks’ gestational age without the need for respiratory support.
- Level II nurseries are subdivided into Level IIA and Level IIB:
- Level IIA nurseries can care for infants ≥32 weeks’ gestational age and ≥1500 grams who do not require respiratory support.
- Level IIB nurseries have the additional ability to care for infants requiring mechanical ventilation for <24 hours or continuous positive pressure ventilation.
- Level III nurseries are the most specialized and are divided into the following categories:
- Level IIIA can care for infants >28 weeks’ gestational age and >1000 grams.
- Level IIIB can care for all infants of all gestational ages and have access to a full range of pediatric subspecialists, including surgical subspecialists.
- Level IV (or level IIIC) can provide extracorporeal membrane oxygenation (ECMO) services or cardiopulmonary bypass.
The following topics in Neonatology are covered in this rotation guide:
Other relevant topics in Neonatology are covered in the following rotation guides: