Qaasim Mian1, Po-Yin Cheung1, Megan O'Reilly1, Gerhard Pichler2, Sylvia van Os3, Karin Kushniruk3, Khalid Aziz1, Georg M Schmölzer1. 1. Center for the Studies of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Edmonton, Canada; Department of Pediatrics, University of Alberta, Edmonton, Canada. 2. Department of Pediatrics, Medical University Graz, Graz, Austria. 3. Center for the Studies of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Edmonton, Canada.
Abstract
OBJECTIVE: To examine the temporal course of lung aeration at birth in preterm infants <33 weeks gestation. STUDY DESIGN: The research team attended deliveries of preterm infants <33 weeks gestation at the Royal Alexandra Hospital. Infants who received only continuous positive airway pressure were eligible for inclusion. A combined carbon dioxide (CO2) and flow-sensor was placed between the mask and the ventilation device. To analyze lung aeration patterns during spontaneous breathing, tidal volume (VT), and exhaled CO2 (ECO2) were recorded for the first 100 breaths. RESULTS: Thirty preterm infants were included with a total of 1512 breaths with mask leak <30%. Mean (SD) gestational age and birth weight was 30 (1) weeks and 1478 (430) g. Initial VT and ECO2 for the first 30 breaths was 5-6 mL/kg and 15-22 mm Hg, respectively. VT and ECO2 increased over the next 20 breaths to 7-8 mL/kg and 25-32 mm Hg, respectively. For the remaining observation period VT decreased to 4-6 mL/kg and ECO2 continued to increase to 35-37 mm Hg. CONCLUSIONS: Preterm infants begin taking deeper breaths approximately 30 breaths after initiating spontaneous breathing to inflate their lungs. Concurrent CO2 removal rises as alveoli are recruited. Lung aeration occurs in 2 phases: initially, large volume breaths with poor alveolar aeration followed by smaller breaths with elimination of CO2 as a consequence of adequate aeration.
OBJECTIVE: To examine the temporal course of lung aeration at birth in preterm infants <33 weeks gestation. STUDY DESIGN: The research team attended deliveries of preterm infants <33 weeks gestation at the Royal Alexandra Hospital. Infants who received only continuous positive airway pressure were eligible for inclusion. A combined carbon dioxide (CO2) and flow-sensor was placed between the mask and the ventilation device. To analyze lung aeration patterns during spontaneous breathing, tidal volume (VT), and exhaled CO2 (ECO2) were recorded for the first 100 breaths. RESULTS: Thirty preterm infants were included with a total of 1512 breaths with mask leak <30%. Mean (SD) gestational age and birth weight was 30 (1) weeks and 1478 (430) g. Initial VT and ECO2 for the first 30 breaths was 5-6 mL/kg and 15-22 mm Hg, respectively. VT and ECO2 increased over the next 20 breaths to 7-8 mL/kg and 25-32 mm Hg, respectively. For the remaining observation period VT decreased to 4-6 mL/kg and ECO2 continued to increase to 35-37 mm Hg. CONCLUSIONS: Preterm infants begin taking deeper breaths approximately 30 breaths after initiating spontaneous breathing to inflate their lungs. Concurrent CO2 removal rises as alveoli are recruited. Lung aeration occurs in 2 phases: initially, large volume breaths with poor alveolar aeration followed by smaller breaths with elimination of CO2 as a consequence of adequate aeration.
Authors: Janneke Dekker; Tessa Martherus; Enrico Lopriore; Martin Giera; Erin V McGillick; Jeroen Hutten; Ruud W van Leuteren; Anton H van Kaam; Stuart B Hooper; Arjan B Te Pas Journal: Front Pediatr Date: 2019-12-12 Impact factor: 3.418
Authors: Samantha K Barton; Mary Tolcos; Suzie L Miller; Charles C Roehr; Georg M Schmölzer; Peter G Davis; Timothy J M Moss; Domenic A LaRosa; Stuart B Hooper; Graeme R Polglase Journal: Front Pediatr Date: 2015-11-10 Impact factor: 3.418