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Published on: August 2, 2024
Sustained pharyngeal inflation on upper airway effects in children-Flexible bronchoscopy measurement
Wen-Jue Soong1,2,3, Chieh-Ho Chen1, Chien-Heng Lin1
1Division of Pediatric Pulmonology, Children's Hospital, China Medical University, Taichung, Taiwan.
Insights
Sustained pharyngeal inflation (SPI) using pharyngeal oxygen and nose-closure (PhO2-NC) for 1-3 seconds effectively increases positive peak inflation pressure (PIP) in children. This simple method enhances pharyngolaryngeal space (PLS) visualization during flexible bronchoscopy (FB).
Area of Science:
- Pediatric Pulmonology
- Respiratory Physiology
- Medical Imaging
Background:
- The pharyngolaryngeal space (PLS) can be challenging to visualize during flexible bronchoscopy (FB) in children.
- Positive pressure ventilation techniques can improve airway lumen expansion and visualization.
Purpose of the Study:
- To measure and compare the effects of different durations of sustained pharyngeal inflation (SPI) using pharyngeal oxygen and nose-closure (PhO2-NC) on positive peak inflation pressure (PIP) within the PLS.
- To assess the impact of SPI duration on PLS lumen expansion and lesion detection during FB.
Main Methods:
- A prospective study involving 20 children (6 months to 3 years) undergoing FB.
- SPI was applied sequentially with durations of 0, 1, 3, and 5 seconds.
- Pharyngeal PIP, PLS lumen expansion scores, and oropharyngeal/supra-laryngeal images were recorded and analyzed.
Main Results:
- Pharyngeal PIP significantly increased with longer SPI durations (p < .001), reaching 65.5 cmH2O at 5 seconds.
- PLS lumen expansion scores and lesion detection also significantly improved with increased SPI duration (p < .004).
- Mean procedural time was 5.7 minutes, with no reported complications.
Conclusions:
- SPI using PhO2-NC for 1-3 seconds is a safe, simple, and effective ventilation strategy for pediatric FB.
- This technique provides adequate PIP to expand the PLS, improving FB performance and visualization in children.
Objective:
Sustained pharyngeal inflation (SPI) with pharyngeal oxygen and nose-closure (PhO2 -NC) can create positive peak inflation pressure (PIP) inside the pharyngolaryngeal space (PLS). This study measured and compared the effects of four different SPI durations in the PLS.
Methods:
A prospective study, 20 consecutive children aged between 6 months and 3 years old, scheduled for elective flexible bronchoscopy (FB) suspected positive PLS findings were enrolled. SPI was performed twice in four different durations (0, 1, 3, and 5 s) sequentially in each infant. PIP was measured for each SPI in the pharynx, while simultaneously record images at two locations of the oropharynx and supra-larynx. Patient demographic details, PIP levels, lumen expansion scores, and images of PLS were measured and analyzed.
Results:
Twenty patients with 40 measurements were collected. The mean (SD) age and weight were 11.6 (9.1) months and 6.8 (2.4) kg, respectively. The measured mean (SD) pharyngeal PIPs were 4.1 (3.3), 21.9 (7.0), 42.2 (12.3), and 65.5 (18.5) cmH2 O at SPI duration of 0, 1, 3, and 5 s, respectively, indicating significant (p<.001) positive correlation. At assigned locations, corresponding PLS images also displayed a significant increase in lumen expansion scores and a number of detected lesions with an increase in SPI duration (p < .004). The mean (SD) procedural time was 5.7 (1.2) min. No study-related complication was noted.
Conclusions:
FB utilizing PhO2 -NC as SPI of 1-3 s is a simple, less invasive, and valuable ventilation modality. It provides an adequate PIP level to expand the PLS and improve FB performance in children.
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