Chest
Original ResearchInterventional PulmonologyThe Effects of Flexible Bronchoscopy on Mechanical Ventilation in a Pediatric Lung Model
Section snippets
The Lung Model
We used a digitally controlled, high-fidelity breathing simulator (ASL 5000; IngMar Medical; Pittsburgh, PA) to simulate respiratory mechanics in children of sizes ranging from infant through young adult. We designed five models with different lung sizes based on weight (4, 15, 30, 50, and 70 kg). We selected lung compliance and airway resistance values that corresponded to “healthy” lungs5, 6 (Table 1). In addition, we assessed the effects of flexible bronchoscopy in obstructive and
Results
A total of 22 bronchoscope/ETT combinations were evaluated (Table 3). For all sets of measurements, the CV for values obtained from 10 consecutive breaths was < 5%; therefore, the values were averaged. In addition, reinserting the bronchoscope did not change the values by > 10% between any of the three runs. As expected, resistance across the ETT increased, often dramatically, after bronchoscope insertion (Table 3).
Discussion
We used a sophisticated lung model to evaluate the effects of bronchoscope insertion during mechanical ventilation of children with normal and abnormal respiratory mechanics. We found that insertion of bronchoscopes through ETTs significantly decreased Vt when in the PC mode of ventilation, and that when in the VC mode, Vt could be maintained in most cases. However, as the bronchoscope-ETT diameter difference decreased, PIP often increased to > 40 cm H2O, and auto-PEEP was generated. As a
References (8)
- et al.
Applications of flexible fiberoptic bronchoscopes in infants and children
Chest
(1978) - et al.
Effects of fiberoptic bronchoscopy during mechanical ventilation in a lung model
Chest
(2000) - et al.
The standardization of bronchoscopic techniques for ventilator-associated pneumonia
Chest
(1992) - et al.
Cardiorespiratory effects of flexible fiberoptic bronchoscopy in critically ill patients
Chest
(1978)
Cited by (29)
Airway evaluation: Bronchoscopy, laryngoscopy, and tracheal aspirates
2022, Goldsmith's Assisted Ventilation of the Neonate: An Evidence-Based Approach to Newborn Respiratory Care, Seventh EditionUltrashort Echo-Time MRI for the Assessment of Tracheomalacia in Neonates
2020, ChestCitation Excerpt :Currently, bronchoscopy relies on a semi-quantitative assessment of airway collapse during spontaneous breathing; unfortunately, bronchoscopy does not take the depth of sedation into account nor the transmural airway pressure, which may alter airway dynamics. The presence of a bronchoscope itself can also alter respiratory mechanics, and it is not clear what effect this may have on tracheal dynamics.29,30 Furthermore, the lack of a standardized definition also allows for interrater variability when interpreting TM based on bronchoscopy, although we achieved very good interrater agreement with agreed upon definitions and extensive training cases.
Percutaneous dilatational tracheostomy with a double-lumen endotracheal tube: A comparison of feasibility, gas exchange, and airway pressures
2015, ChestCitation Excerpt :MV and Vt decreased more in the conventional ETT group than in the DLET group during PDT. Other studies have also documented a reduction in MV from 35% to 73% due to different ETT and FFB combinations during PDT.24,25 In the present study, the use of a 5-mm external diameter FFB decreased the MV by 40% in the conventional ETT group and only 19% in the DLET group, whereas the Vt was reduced 34% (ETT) and 7% (DLET).
Airway ventilation pressures during bronchoscopy, bronchial blocker, and double-lumen endotracheal tube use: An in vitro study
2014, Journal of Cardiothoracic and Vascular AnesthesiaFiberoptic bronchoscopy in a respiratory intensive care unit
2012, Medicina IntensivaA convenient, practical adapter for bronchotracheoscopy through a tracheostomy tube in a ventilator-dependent patient
2010, Otolaryngology - Head and Neck Surgery
This article was presented in part at the 2007 International Conference of the American Thoracic Society, San Francisco, CA, May 18–23, 2007.
The authors have reported to the ACCP that no significant conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestjournal.org/misc/reprints.shtml).