For adults a correlation between the occurrence of obstructive sleep a
pnoea and organic diseases is proven. In preterm or newborn infants al
so central or obstructive apnoea can be observed, lasting up to thirty
seconds or even longer. The evaluation of apnoea is of diagnostic imp
ortance and so far is carried out subjectively by physicians. We sugge
st a new apnoea severity factor, calcualted automatically using respir
atory and blood gas values from polysomnographic recordings. The compu
ted apnoea severity values are in very good correspondence with subjec
tive judgements.