A newborn has roughly a cup of blood per kilogram of body weight. A 2.5 kg baby carries barely 200 mL total, which is why paediatric transfusion is the most careful corner of blood medicine. ## When babies need blood - Anaemia of prematurity, early babies cannot yet make enough red cells
- Rh/ABPD jaundice needing exchange transfusion, the baby’s blood is swapped in small cycles (see rh-and-pregnancy)
- Thalassemia and other conditions starting in infancy, lifelong transfusion
- Surgery for congenital heart defects ## What makes their units different - Tiny, weight-based doses, sometimes 10,20 mL per kilogram, dosed like a medicine
- Fresh units, often under 7 days old, with the red cells still maximally effective
- Extra matching, extended crossmatch, sometimes CMV-safe or irradiated components for the smallest or most immune-vulnerable babies
- Paediatric bags, one adult donation split into several paediatric doses, so one donor serves one baby without multiple donor exposures ## Where the blood comes from From ordinary adult donors, screened, tested, processed exactly as always, then split and prepared for the smallest patients. O− donors are the emergency default for untyped neonates. There is no special “baby donor”: there is the same register, the same ten minutes, the same arm. ## For parents of a baby who needs transfusion The neonatal unit and blood centre handle preparation and matching, you do not need to find a “matching baby donor”. What the system needs from everyone else is the steady voluntary supply behind the shelf: register, and answer when the alert comes. Related: rh-and-pregnancy · regular donors for thalassemia · journey of a blood bag