Blood transfusions for preterm infants and free radicals

INTERVENTION: Group 1 will have their need for blood transfusion monitored according to a standard protocol. Group 2 will have measurements of forearm fractional oxygen extraction (FOE) to guide their need for transfusions. CONDITION: Neonatal diseases ; Neonatal Diseases PRIMARY OUTCOME: The primary outcome measure will be peak ODFR activity. SECONDARY OUTCOME: A secondary outcome will be the number of days on the neonatal unit, retinopathy or prematurity, preventricular haemorrhage and periventricular leukomalacia and necrotising enterocolitis. INCLUSION CRITERIA: Preterm infants