Cyanotic Breath-holding Spells Research Articles

Reduced haemoglobin levels in infants presenting with apparent life-threatening events--a retrospective investigation.

Anaemia has been shown to be associated with an increased apnoeic pause frequency and with cyanotic breath-holding spells. In this study, the relationship between anaemia and apparent life-threatening events was retrospectively investigated in 72 term infants referred for assessment and home monitoring following an apparent life-threatening event. For 41 infants (25 male, 16 female; 38 Caucasian, three Asian) a venous red blood cell count was available. Their median age at the time of the apparent life-threatening event was 2.0 (0.6-6.7) months. The Hb levels in these 41 infants were plotted against normal data from the literature. Thirty-four infants had Hb levels below the mean, whilst six infants had values above the corresponding normal mean; the one remaining infant had a Hb value identical to the normal mean. Significantly more infants than expected had Hb levels below the mean (p less than 0.001, binomial test). Anaemia may have played a role in the pathophysiology leading to life-threatening events in some of the infants investigated in this study.

Ventilatory Chemosensitivity in Subjects with a History of Childhood Cyanotic Breath-Holding Spells

The ability of children with cyanotic breath-holding spells to respond to anger or frustration by voluntary breath-holding for prolonged periods (often to the point of precipitating hypoxic seizure activity) suggested the hypothesis that such children may have a less powerful urge to breathe in the presence of hypoxia and/or hypercapnia than children who do not have breath-holding spells. Because ventilatory chemosensitivity is difficult to measure in infants and young children, this hypothesis was tested indirectly by measuring the ventilatory responses to hyperoxic progressive hypercapnia and to isocapnic progressive hypoxia of seven individuals who had a history of cyanotic breath-holding spells in infancy and 17 control subjects. The mean values for sensitivity to hypoxia and to hypercapnia were not significantly different between the two groups, and the responses of the majority of the subjects with cyanotic breath-holding spells were clearly within the normal range. There were fewer individuals with high-normal ventilatory responses among the subjects with cyanotic breath-holding spells. Although children with cyanotic breath-holding spells may have decreased ventilatory chemosensitivity transiently during infancy or may differ from other children in some other aspect of the control of breathing, the pathogenesis of infantile cyanotic breath-holding spells does not involve a permanently blunted sensitivity to hypercapnia or hypoxia.