In utero exposure to smoking and peripheral chemoreceptor function in preterm neonates.
OBJECTIVE
We aimed to assess the involvement of peripheral chemoreceptor tonic activity in the ventilatory pattern during sleep in preterm neonates exposed in utero to maternal smoking.


METHODS
Peripheral chemoreceptor activity was measured at thermoneutrality in neonates (postmenstrual age: 36.1 +/- 1.2 weeks) born to nonsmoking (n = 21) or smoking (n = 16) mothers by performing a 30-second hyperoxic test during active and quiet sleep. Blood oxygen saturation, baseline ventilatory parameters, and central apnea were monitored.


RESULTS
Prenatal smoking exposure did not modify baseline ventilation. It was interesting to note that prenatal smoking exposure decreased the peripheral chemoreceptor tonic activity during active sleep and increased the response time during quiet sleep. These changes could explain the increase in the time spent in apnea (both with and without blood oxygen desaturation) and in the mean duration of apneic episodes with desaturation found in neonates exposed to smoking in utero. The involvement of a change in the chemoreceptor function is supported by the fact that the peripheral chemoreceptor tonic activity was negatively correlated with the mean duration of apneic episodes with desaturation in the control group only.


CONCLUSIONS
To our knowledge, this is the first study to reveal that prenatal smoking exposure does not directly modify baseline ventilatory parameters in the neonate but has a negative impact on peripheral chemoreceptor tonic activity. These alterations may increase the risk of sleep respiratory disorders, especially via apnea with desaturation.
Stéphan-Blanchard
Erwan
E
Jules Verne University of Picardy, Faculté de Médecine, 3 Rue des Louvels, 80036 Amiens Cedex, France. erwan.stephan@u-picardie.fr
Chardon
Karen
K
Léké
André
A
Delanaud
Stéphane
S
Djeddi
Djamal
D
Libert
Jean-Pierre
JP
Bach
Véronique
V
Telliez
Frédéric
F
D000328:Adult; D001049:Apnea / Q000453:epidemiology / Q000209:etiology; D002628:Chemoreceptor Cells / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D009035:Mothers; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012132:Respiratory Muscles / Q000187:drug effects / Q000502:physiology; D012907:Smoking / Q000009:adverse effects; D055815:Young Adult