Background: Diminished lung function appears to be a risk factor for respirato ry syncytial virus (RSV) infection/bronchiolitis in term born infants. Aims: To determine if diminished lung function prior to neonatal un...Background: Diminished lung function appears to be a risk factor for respirato ry syncytial virus (RSV) infection/bronchiolitis in term born infants. Aims: To determine if diminished lung function prior to neonatal unit discharge was assoc iated with subsequent symptomatic RSV lower respiratory tract infection (LRTI) a nd respiratory morbidity in prematurely born infants. Methods: Of 39 infants in a tertiary neonatal intensive care unit (median gestational age 28 weeks, range 23-31), 20 had bronchopulmonary dysplasia. Lung function (compliance and resist ance of the respiratory system(Crs and R rs) and functional residual capacity (F RC)) was measured on the neonatal unit at 36 weeks postmenstrual age (PMA). Foll owing neonatal unit discharge, nasopharyngeal aspirates were obtained on every o ccasion, at home or in hospital, an infant had an LRTI. RSV was identified by im munofluorescence and/or culture. Results: The 15 infants who suffered a symptoma tic RSV LRTI had a higher mean Rrs and suffered more wheeze at follow up than th e rest of the cohort. Regression analysis showed that a high Rrs was significant ly associated with a symptomatic RSV LRTI; significant factors for cough were a high Rrs and a symptomatic RSV LRTI, and for wheeze were a high Rrs. Conclusion: Prematurely born infants, who had a symptomatic RSV LRTI and/or respiratory mor bidity at follow up, had worse lung function prior to neonatal unit discharge.展开更多
Term newborns can compensate fully for an imposed dead space (tube breathing) by increasing their minute ventilation. Objective: To test the hypothesis that infants of smoking mothers would have an impaired response t...Term newborns can compensate fully for an imposed dead space (tube breathing) by increasing their minute ventilation. Objective: To test the hypothesis that infants of smoking mothers would have an impaired response to tube breathing. Design: Prospective study. Setting: Perinatal service. Patients: Fourteen infants of smoking and 24 infants of non-smoking mothers (median postnatal age 37 (11- 85) hours and 26 (10- 120) hours respectively) were studied. Interventions: Breath by breath minute volume was measured at baseline and when a dead space of 4.4 ml/kg was incorporated into the breathing circuit. Main outcome measures: The maximum minute ventilation during tube breathing was determined and the time constant of the response calculated. Results: The time constant of the infants of smoking mothers was longer than that of the infants of non-smoking mothers (median (range) 37.3 (22.2- 70.2) v 26.2 (13.8- 51.0) seconds, p = 0.016). Regression analysis showed that maternal smoking status was related to the time constant independently of birth weight, gestational or postnatal age, or sex (p = 0.018). Conclusions: Intrauterine exposure to smoking is associated with a dampened response to tube breathing.展开更多
文摘Background: Diminished lung function appears to be a risk factor for respirato ry syncytial virus (RSV) infection/bronchiolitis in term born infants. Aims: To determine if diminished lung function prior to neonatal unit discharge was assoc iated with subsequent symptomatic RSV lower respiratory tract infection (LRTI) a nd respiratory morbidity in prematurely born infants. Methods: Of 39 infants in a tertiary neonatal intensive care unit (median gestational age 28 weeks, range 23-31), 20 had bronchopulmonary dysplasia. Lung function (compliance and resist ance of the respiratory system(Crs and R rs) and functional residual capacity (F RC)) was measured on the neonatal unit at 36 weeks postmenstrual age (PMA). Foll owing neonatal unit discharge, nasopharyngeal aspirates were obtained on every o ccasion, at home or in hospital, an infant had an LRTI. RSV was identified by im munofluorescence and/or culture. Results: The 15 infants who suffered a symptoma tic RSV LRTI had a higher mean Rrs and suffered more wheeze at follow up than th e rest of the cohort. Regression analysis showed that a high Rrs was significant ly associated with a symptomatic RSV LRTI; significant factors for cough were a high Rrs and a symptomatic RSV LRTI, and for wheeze were a high Rrs. Conclusion: Prematurely born infants, who had a symptomatic RSV LRTI and/or respiratory mor bidity at follow up, had worse lung function prior to neonatal unit discharge.
文摘Term newborns can compensate fully for an imposed dead space (tube breathing) by increasing their minute ventilation. Objective: To test the hypothesis that infants of smoking mothers would have an impaired response to tube breathing. Design: Prospective study. Setting: Perinatal service. Patients: Fourteen infants of smoking and 24 infants of non-smoking mothers (median postnatal age 37 (11- 85) hours and 26 (10- 120) hours respectively) were studied. Interventions: Breath by breath minute volume was measured at baseline and when a dead space of 4.4 ml/kg was incorporated into the breathing circuit. Main outcome measures: The maximum minute ventilation during tube breathing was determined and the time constant of the response calculated. Results: The time constant of the infants of smoking mothers was longer than that of the infants of non-smoking mothers (median (range) 37.3 (22.2- 70.2) v 26.2 (13.8- 51.0) seconds, p = 0.016). Regression analysis showed that maternal smoking status was related to the time constant independently of birth weight, gestational or postnatal age, or sex (p = 0.018). Conclusions: Intrauterine exposure to smoking is associated with a dampened response to tube breathing.
