We studied the effect of blood transfusion on the frequency of apnoea, bradycardia and hypoxaemia in 21 spontaneously breathing preterm infants with a median gestational age at birth of 28 (range 23-31) weeks. Age at time of study was 22 days (3-84), weight 925 g (640-2120). The patients exhibited frequent episodes of bradycardia and/or hypoxaemia and were anaemic (median haemoglobin level 109 (82-120) g/l). One infant received two transfusions and was thus studied twice. Four-hour recordings of pulse oximeter saturation (SpO2), pulse waveforms, transcutaneous oxygen pressure, electrocardiogram, breathing movements and nasal airflow were performed immediately before and after transfusion, and again after a further interval of 12 h. Recordings were analysed for isolated and periodic apnoeas (> 4 s), bradycardias (heart rate < 2/3 of baseline), and episodic desaturation (SpO2 < or = 80%). There were no significant changes in the frequency, severity and/or duration of apnoea, bradycardia or desaturation following transfusion. The average SpO2 nadir reached during each desaturation, however, increased by 3% following transfusion (P < 0.05), and there was a trend towards shorter desaturations.
Conclusion: The occurrence of frequent episodes of apnoea, bradycardia and/or hypoxaemia does not, on its own, justify a blood transfusion in moderately anaemic preterm infants.