The strength of the breuer-hering inflation reflex in term and
preterm infants.
De, J. P., Winter, I. T. Merth, A. Berkenbosch, R. Brand, and Ph. H.
Quanjer.
Departments of Pediatrics, Physiology and Medical Statistics,
Leiden University, Leiden, The Netherlands
APStracts 2:0345A, 1995.
The effect of the presence of the respiratory distress syndrome (RDS)
or related factors (static compliance (Crs) and transcutaneous blood
gases) and gestational age on the strength of the Breuer-Hering
inflation reflex (BHIR) was studied in three groups of infants.
Twenty-six ventilated preterm infants with and without RDS were
studied 6 hours after birth (group 1). In 23 preterm infants we
followed the development of reflex strength during the first year of
life (group 2). Twenty-one healthy non-intubated term infants were
studied within the first week of life (group 3). The BHIR was
initiated by end-inspiratory occlusions, and the strength
characterized by the ratio of expiratory time following and without
preceding airway occlusion. Crs in ventilated infants was assessed by
the multiple occlusion technique. In group 1, reflex strength
declined with increasing gestational age; in the presence of RDS or
low respiratory compliance decline was less. Transcutaneous blood
gases did not affect reflex strength. At term age, reflex strength
was similar in spontaneously breathing preterm (group 2) and term
infants (group 3). The BHIR decreased in strength during the first
year after preterm birth. We conclude 1) that the strength of the
BHIR decreases with increasing gestational and postnatal age; 2) RDS,
due to changes in respiratory system mechanics, causes an increase in
reflex strength.
Received 2 August 1994; accepted in final form 10 july 1995.
APS Manuscript Number A791-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 14 August 1995.