Response to Duke et al

• hypoxaemia
• respiratory illness

We read with interest the article by Duke et al¹ regarding hypoxaemia in acute respiratory and non-respiratory illnesses in infants and children in developing countries published recently in Archives.¹ The authors have rightly pointed out the limited availability of published data on the incidence, significance or clinical signs predicting hypoxaemia in infants less than three months of age. With similar concerns we had conducted a study in infants less than two months, a part of which was published in the Archives.² We found that tachypnoea, defined as RR>60/min, predicted hypoxia with 80% sensitivity and 68% specificity.² In that study we had also examined six functional and behavioural responses as predictors of hypoxemia (table 1). Five of these …