Cumulative Effects of Positive Pressure Ventilation on the Development of Chronic Lung Disease in Very Low Birth Weight Infants

ABSTRACT

PURPOSE: Barotrauma is one of the most important risk factors of chronic lung disease (CLD) in neonates. However, so-often called `high pressure' does not specify the magnitude or duration of positive pressure ventilation in relation to development of CLD. We investigated whether cumulative effect of positive pressure ventilation over time was more closely associated with CLD than the magnitude of maximal peak inspiratory pressure (PIP) or mean airway pressure (MAP). METHODS: Clinical data were collected from 53 very low birth weight (VLBW) infants (24; CLD and 29; non-CLD) who were treated with mechanical ventilation due to respiratory distress syndrome (RDS) at the neonatal intensive care unit (NICU) in Yonsei University Medical Center. Areas under the pressure-time curve for peak inspiratory pressure (AUCPIP), mean airway pressure (AUCMAP), and FiO2 (AUCFiO2) were calculated from hourly changes of the ventilatory parameters plotted against time during the first 5 days of life, and were compared with the magnitudes of episodic, maximum PIP, MAP or FiO2. RESULTS: The AUCMAP and AUCPIP in CLD group was significantly higher than in non-CLD group (639.8+/-142.9 cmH2O hr vs. 474.2+/-148.0 cmH2O hr, P 0.05). After statistical correction for independent factors related to development of CLD, AUCMAP was shown to be most meaningful. CONCLUSION: Our data are suggestive of the importance of cumulative barotrauma over time in CLD rather than episodic barotrauma caused by cross-sectional or intermittent high peak pressures.