Ventilatory Response to Hypercarbia in Newborns of Smoking and Substance Misusing Mothers

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)


Rationale: Infants of mothers who smoked (S) or substance misused (SM) during pregnancy have an increased risk of sudden infant death syndrome (SIDS). 

Objectives: To test the hypothesis that infants of S and SM mothers compared to infants of non substance misusing, non-smoking mothers (controls) would have a reduced ventilatory response to hypercarbia and that any reduction would be greater in the SM infants. 

Methods: Infants were assessed before maternity/neonatal unit discharge. Maternal and infant urine samples were obtained and tested for cotinine, cannabinoids, opiates, amphetamines, methadone, cocaine and benzodiazepines. 
Measurements and main results: Respiratory flow and tidal volume were measured using a pneumotachograph inserted into a face mask placed over the infant's mouth and nose. The ventilatory responses to three levels of inspired carbon dioxide (0% (baseline), 2% and 4% CO2) were assessed. Twenty-three SM, 34 S and 22 control infants were assessed. The birth weight of the controls was higher than the SM and S infants (p=0.017). At baseline, SM infants had a higher respiratory rate (p=0.003) and minute volume (p=0.007) compared to controls and S infants. Both the SM and S infants had a lower ventilatory response to 2% (p<0.001) and 4% (p<0.001) CO2 than the controls. The ventilatory response to CO2 was lower in the SM infants compared to the S infants (p=0.009). 

Conclusions: These results are consistent with infants of smoking mothers and substance misuse/smoking mothers having a dampened ventilatory response to hypercarbia, which is particularly marked in the latter group.
Original languageEnglish
Pages (from-to)933-938
Number of pages6
JournalAnnals of the American Thoracic Society
Issue number6
Publication statusPublished - Jul 2014


Dive into the research topics of 'Ventilatory Response to Hypercarbia in Newborns of Smoking and Substance Misusing Mothers'. Together they form a unique fingerprint.

Cite this