📚 Sources & Fact-Checking

Real doctors cite their sources — so this tutor does too. The medical facts in these lessons were checked against the references below (as of August 2026). Medicine updates constantly; details like exact target ranges can shift as new studies land.

Vital signs & blood pressure

Normal newborn ranges (heart rate ~100–160/min, breathing ~30–60/min, term BP ~60–80/40–50): standard pediatric references, e.g. newborn vital sign summaries consistent with AAP/PALS teaching.
The “MAP ≥ gestational age” rule of thumb comes from the British Association of Perinatal Medicine's joint working group; its limits and the “treat the baby, not the number” caution are discussed in reviews of preterm hypotension and commentaries on permissive hypotension.

Oxygen & pulse oximetry

How pulse oximeters work (red ~660 nm and infrared ~940 nm light, differential hemoglobin absorption): Open Critical Care, Deranged Physiology.
Preterm saturation targets: the SUPPORT trial (NEJM 2010) and the NeOProM meta-analysis of five trials — lower targets (85–89%) increased mortality, higher (91–95%) increased treated ROP; current practice targets roughly 90–95% (narrative review).
The 1940s–50s oxygen-and-blindness epidemic and its history: National Eye Institute and historical reviews of retinopathy of prematurity. Stevie Wonder's prematurity and ROP are widely documented public biography.

Apnea, monitors & caffeine

Apnea of prematurity (pauses ~20 seconds, or shorter with bradycardia/desaturation; affects most infants born before ~34 weeks): standard neonatology references, e.g. reviews of methylxanthine therapy.
The CAP trial (~2,006 infants): caffeine reduced bronchopulmonary dysplasia and improved survival without neurodevelopmental disability at 18 months, with benefits persisting at 11-year follow-up.

Lungs, surfactant & RDS

Surfactant physiology and the transformation of RDS: Historical perspective on surfactant therapy (Seminars in Fetal & Neonatal Medicine).
Avery & Mead's 1959 discovery that RDS lungs lack surfactant; first successful trials in the 1980s; FDA approvals around 1990: same historical reviews and NHLBI history.
Patrick Bouvier Kennedy: born ~5.5 weeks early on August 7, 1963; died of hyaline membrane disease (RDS) at 39 hours: Neonatology on the Web.
Antenatal corticosteroids for lung maturation: long-established obstetric standard (NIH consensus; Cochrane reviews).

Feeding & nutrition

Suck-swallow-breathe coordination emerging ~32–34 weeks (breathing coordination maturing toward 37): feeding readiness literature.
Human milk lowering NEC risk, donor milk banking, TPN and line practices: AAP policy on human milk; KidsHealth on NEC; HMBANA.
Birth-weight categories (LBW <2500 g, VLBW <1500 g, ELBW <1000 g): WHO/AAP standard definitions.

Jaundice & phototherapy

Bilirubin photochemistry (blue/blue-green light ~460–490 nm converting bilirubin to excretable isomers including lumirubin): AAP phototherapy technical report (2024) and Pediatric Research reviews.
Sister Jean Ward's 1956 observation at Rochford Hospital leading to Cremer's phototherapy work: documented in the history of neonatal phototherapy.
Hour-specific bilirubin thresholds and kernicterus prevention: AAP 2022 hyperbilirubinemia clinical practice guideline.

Brain, heart & imaging

IVH grading (1–4), germinal matrix origin, and routine cranial ultrasound screening for infants born before ~30–32 weeks with first scan in the first week: StatPearls and comprehensive reviews.
Ductus arteriosus normally closing functionally within ~1–3 days in term infants; PDA in up to ~64% of infants born 27–28 weeks; treatment with ibuprofen/indomethacin/acetaminophen or transcatheter closure: AAP clinical report on PDA (2025).

Survival & the edge of viability

US survival to discharge among extremely preterm infants receiving active NICU care, 2020–2022: ~35% at 22 weeks, ~55% at 23 weeks, ~71% at 24 weeks, ~82% at 25 weeks, with high rates of major complications among the earliest survivors: Pediatrics 2024.