Lung Mechanics in Premature infants: Modelling and clinical validation

Abstract

Abstract Mechanical ventilation (MV) is widely used in Neonatal Intensive Care Unit (NICU) to support or fully control the breathing of patients of patients with respiratory distress syndrome (RDS). Current clinical practice involves clinician intuition or a generalized, “one size fits all” approach as inter-patient variability and lung heterogeneity can make selection of optimum ventilator settings difficult. Model-based methods can be used to identify patient-specific lung mechanics. This study aims to apply the single compartment lung model with an added endotracheal tube compensation term (ΔPett) to fit neonatal clinical data to describe neonatal lung mechanics. Airway flow and pressure data was collected from 10 mechanically ventilated infants in the Christchurch women’s hospital NICU as part of an observational trial under standard care conditions. 205.9 hours of conventional ventilation (across 9 patients), and 53 hours of HFOV (across 3 patients) were recorded. The model fit was very good with median [interquartile range] of percentage MARD of 5.7 [5.2-6.3]% across all conventionally ventilated patients. Subgroup analyses was also performed based on weight, RDS and surgical cohort, and comparison between patients who were treated and not treated with surfactant therapy. Overall, the single compartment model fit was able to capture lung mechanics in premature infants, but showed large variability in mechanics across and within patients. Future work will use these results and models to better understand and monitor changes in patient condition for the improvement of delivered MV.