Abstract
It has been well established that slowly adapting vagal stretch receptors (the Hering-Breuer reflex) are active in new-born infants, while the vagal rapidly adapting (irritant) receptors have not been studied. We have tested the activity of the irritant receptors in two ways by 1. rapid lung deflation with negative pressure (- 5 cm) applied via a face mask; and 2. direct stimulation of the bronchial mucosa with a fine catheter in intubated infants. Rapid lung deflation in 8 infants (gestation 29-40 weeks) failed to stimulate respiration in all (control frequency 46±16; frequency during deflation 43±16, mean±SD). Direct bronchial mucosal stimulation in 8 intubated babies (gestation 29-39 weeks) failed to stimulate respiration in 5 infants less than 35 weeks gestation. In 3 Infants, 35-39 weeks, respiratory frequency markedly increased or the infant coughed.
The failure to elicit a deflation reflex in all infants, and the absence of response to mucosal stimulation in some infants suggests that vagal irritant reflexes are weak or absent in human newborns. This may be one reason why aspiration is common in this age group.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fleming, P., Bryan, H. & Bryan, A. PULMONARY IRRITANT REFLEXES IN NEWBORN INFANTS. Pediatr Res 11, 570 (1977). https://doi.org/10.1203/00006450-197704000-01200
Issue Date:
DOI: https://doi.org/10.1203/00006450-197704000-01200