Chamindu C Gunatilaka1, Erik B Hysinger2, Andreas Schuh3, Deep B Gandhi4, Nara S Higano5, Qiwei Xiao5, Andrew D Hahn6, Sean B Fain6, Robert J Fleck7, Jason C Woods8, Alister J Bates9. 1. Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Physics, University of Cincinnati, Cincinnati, OH. 2. Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH. 3. Department of Computing, Imperial College London, London, UK. 4. Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH. 5. Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH. 6. Department of Medical Physics, University of Wisconsin-Madison, Madison, WI. 7. Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH. 8. Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Physics, University of Cincinnati, Cincinnati, OH; Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH. 9. Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, OH. Electronic address: Alister.Bates@cchmc.org.
Abstract
BACKGROUND: In pediatrics, tracheomalacia is an airway condition that causes tracheal lumen collapse during breathing and may lead to the patient requiring respiratory support. Adult patients can narrow their glottis to self-generate positive end-expiratory pressure (PEEP) to raise the pressure in the trachea and prevent collapse. However, auto-PEEP has not been studied in newborns with tracheomalacia. The objective of this study was to measure the glottis cross-sectional area throughout the breathing cycle and to quantify total pressure difference through the glottis in patients with and without tracheomalacia. RESEARCH QUESTION: Do neonates with tracheomalacia narrow their glottises? How does the glottis narrowing affect the total pressure along the airway? STUDY DESIGN AND METHODS: Ultrashort echo time MRI was performed in 21 neonatal ICU patients (11 with tracheomalacia, 10 without tracheomalacia). MRI scans were reconstructed at four different phases of breathing. All patients were breathing room air or using noninvasive respiratory support at the time of MRI. Computational fluid dynamics simulations were performed on patient-specific virtual airway models with airway anatomic features and motion derived via MRI to quantify the total pressure difference through the glottis and trachea. RESULTS: The mean glottis cross-sectional area at peak expiration in the patients with tracheomalacia was less than half that in patients without tracheomalacia (4.0 ± 1.1 mm2 vs 10.3 ± 4.4 mm2; P = .002). The mean total pressure difference through the glottis at peak expiration was more than 10 times higher in patients with tracheomalacia compared with patients without tracheomalacia (2.88 ± 2.29 cm H2O vs 0.26 ± 0.16 cm H2O; P = .005). INTERPRETATION: Neonates with tracheomalacia narrow their glottises, which raises pressure in the trachea during expiration, thereby acting as auto-PEEP.
BACKGROUND: In pediatrics, tracheomalacia is an airway condition that causes tracheal lumen collapse during breathing and may lead to the patient requiring respiratory support. Adult patients can narrow their glottis to self-generate positive end-expiratory pressure (PEEP) to raise the pressure in the trachea and prevent collapse. However, auto-PEEP has not been studied in newborns with tracheomalacia. The objective of this study was to measure the glottis cross-sectional area throughout the breathing cycle and to quantify total pressure difference through the glottis in patients with and without tracheomalacia. RESEARCH QUESTION: Do neonates with tracheomalacia narrow their glottises? How does the glottis narrowing affect the total pressure along the airway? STUDY DESIGN AND METHODS: Ultrashort echo time MRI was performed in 21 neonatal ICU patients (11 with tracheomalacia, 10 without tracheomalacia). MRI scans were reconstructed at four different phases of breathing. All patients were breathing room air or using noninvasive respiratory support at the time of MRI. Computational fluid dynamics simulations were performed on patient-specific virtual airway models with airway anatomic features and motion derived via MRI to quantify the total pressure difference through the glottis and trachea. RESULTS: The mean glottis cross-sectional area at peak expiration in the patients with tracheomalacia was less than half that in patients without tracheomalacia (4.0 ± 1.1 mm2 vs 10.3 ± 4.4 mm2; P = .002). The mean total pressure difference through the glottis at peak expiration was more than 10 times higher in patients with tracheomalacia compared with patients without tracheomalacia (2.88 ± 2.29 cm H2O vs 0.26 ± 0.16 cm H2O; P = .005). INTERPRETATION: Neonates with tracheomalacia narrow their glottises, which raises pressure in the trachea during expiration, thereby acting as auto-PEEP.
Authors: Marina Piccinelli; Alessandro Veneziani; David A Steinman; Andrea Remuzzi; Luca Antiga Journal: IEEE Trans Med Imaging Date: 2009-05-12 Impact factor: 10.048
Authors: Nara S Higano; David R Spielberg; Robert J Fleck; Andrew H Schapiro; Laura L Walkup; Andrew D Hahn; Jean A Tkach; Paul S Kingma; Stephanie L Merhar; Sean B Fain; Jason C Woods Journal: Am J Respir Crit Care Med Date: 2018-11-15 Impact factor: 30.528
Authors: Chamindu C Gunatilaka; Erik B Hysinger; Andreas Schuh; Qiwei Xiao; Deep B Gandhi; Nara S Higano; Daniel Ignatiuk; Md M Hossain; Robert J Fleck; Jason C Woods; Alister J Bates Journal: J Appl Physiol (1985) Date: 2022-09-01