The influence of body position on pulmonary function in low birthweight babies.

The influence of the prone and supine body positions on the respiratory rate, arterial pH, pO2, pCO2 and serum bicarbonate level; on alveolar pO2 and pCO2; and on alveolar/arterial gradients for carbon dioxide and oxygen, were compared in 10 low birthweight infants. THE ALveolar pCO2 was higher in the prone, while pO2 was higher in the supine position, possibly as a result of ventilation/perfusion imbalance with increased physiological dead space in the supine position. There were no significant differences between the other parameters studied. Since aspiration of feed by the low birthweight infant is a major cause of morbidity and mortality, evidence is presented in favour of the prone nursing position.