M Katz-Salamon1. 1. Dept for Women's and Child Health, Karolinska Institute, Elevhemmet H1O2, S-171 76 Stockholm, Sweden. miriam.katz-salamon@ks.se
Abstract
AIMS: To test the hypothesis that apnoea of infancy (AOI) is due to a deficit in chemoreception. METHODS: Tests were performed on 112 infants: 43 healthy control infants, 28 infants with periodic breathing or central apnoea (PBCA), and 41 infants with obstructive apnoea (OA) on overnight polysomnography. Chemoreceptor responses to hypercapnia (4% and 6% CO2 in air) for 6-8 minutes and hyperoxia (100% O2) for 60 seconds were expressed in terms of response strength and reaction time. Age at birth (gestational week 37-41) and age at test (2-34 postnatal weeks) were comparable across groups (median, min-max value). A total of 70 CO2 and 71 O2 tests were analysed. RESULTS: The strongest and fastest CO2 responders were control infants: their median increase in ventilation was 291%/kPaCO2 and their reaction time 16 breaths. In infants with PBCA and OA, the increase in ventilation was 41% and 130%/kPaCO2, and reaction time 64 and 54 breaths, respectively. There was a significant negative correlation between CO2 response strength and response time. In response to hyperoxia there was a comparable decrease in ventilation in all infants (12-20%), but a significantly longer response time in infants with apnoea (20 v 12 breaths). There was no correlation between the response strength and response time to O2 and CO2. CONCLUSION: An inappropriate central control of respiration is an important mechanism in the pathogenesis of apnoea of infancy.
AIMS: To test the hypothesis that apnoea of infancy (AOI) is due to a deficit in chemoreception. METHODS: Tests were performed on 112 infants: 43 healthy control infants, 28 infants with periodic breathing or central apnoea (PBCA), and 41 infants with obstructive apnoea (OA) on overnight polysomnography. Chemoreceptor responses to hypercapnia (4% and 6% CO2 in air) for 6-8 minutes and hyperoxia (100% O2) for 60 seconds were expressed in terms of response strength and reaction time. Age at birth (gestational week 37-41) and age at test (2-34 postnatal weeks) were comparable across groups (median, min-max value). A total of 70 CO2 and 71 O2 tests were analysed. RESULTS: The strongest and fastest CO2 responders were control infants: their median increase in ventilation was 291%/kPaCO2 and their reaction time 16 breaths. In infants with PBCA and OA, the increase in ventilation was 41% and 130%/kPaCO2, and reaction time 64 and 54 breaths, respectively. There was a significant negative correlation between CO2 response strength and response time. In response to hyperoxia there was a comparable decrease in ventilation in all infants (12-20%), but a significantly longer response time in infants with apnoea (20 v 12 breaths). There was no correlation between the response strength and response time to O2 and CO2. CONCLUSION: An inappropriate central control of respiration is an important mechanism in the pathogenesis of apnoea of infancy.
Authors: Mar Janna Dahl; Sydney Bowen; Toshio Aoki; Andrew Rebentisch; Elaine Dawson; Luke Pettet; Haleigh Emerson; Baifeng Yu; Zhengming Wang; Haixia Yang; Chong Zhang; Angela P Presson; Lisa Joss-Moore; Donald M Null; Bradley A Yoder; Kurt H Albertine Journal: Am J Physiol Lung Cell Mol Physiol Date: 2018-09-13 Impact factor: 5.464
Authors: Manisha Patel; Mary Mohr; Douglas Lake; John Delos; J Randall Moorman; Robert A Sinkin; John Kattwinkel; Karen Fairchild Journal: Pediatr Res Date: 2016-03-22 Impact factor: 3.756
Authors: Karen Fairchild; Mary Mohr; Alix Paget-Brown; Christa Tabacaru; Douglas Lake; John Delos; Joseph Randall Moorman; John Kattwinkel Journal: Pediatr Res Date: 2016-03-09 Impact factor: 3.756