Sound Analysis in an In Vitro Endotracheal Tube Model.
10.3904/kjim.2011.26.4.421
- Author:
Young Sik PARK
1
;
Young Wook KEE
;
Kwang Suk PARK
;
Jinwoo LEE
;
Sang Min LEE
;
Jae Joon YIM
;
Chul Gyu YOO
;
Young Whan KIM
;
Sung Koo HAN
;
Seok Chul YANG
Author Information
1. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine and Lung Institute, Seoul National University College of Medicine, Seoul, Korea. scyang@snu.ac.kr
- Publication Type:Original Article ; In Vitro
- Keywords:
Intubation, intratracheal;
Sound;
Airway obstruction
- MeSH:
*Airway Obstruction;
Confidence Intervals;
Exhalation;
Humans;
*Intubation, Intratracheal;
Models, Theoretical;
Positive-Pressure Respiration;
Statistics as Topic
- From:The Korean Journal of Internal Medicine
2011;26(4):421-426
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND/AIMS: Complete endotracheal tube obstruction is a medical emergency, and partial occlusion causes increased breathing rates and failure to wean off mechanical ventilation. Partial occlusion may be underestimated due to the lack of proper detection methods. We tested whether the sound of an endotracheal tube could be used to detect an endotracheal tube obstruction using an in vitro model. METHODS: An endotracheal tube was connected to a ventilator on one end and a test lung on the other. Sounds were recorded with a microphone located inside the endotracheal tube via a connector. During mechanical ventilation, we changed the endotracheal tube internal diameter from 5.0 to 8.0 mm and different grades of obstruction at different sites were used along the tube. Sound energy was compared among the different conditions. RESULTS: The energy of endotracheal tube sounds was positively correlated with the internal diameter and negatively correlated with the degree of obstruction. The rate of decline in energy differed with obstruction location. When the obstruction was more distal, the rate of decline in endotracheal sound energy was more rapid. CONCLUSIONS: Changes in the sound of an endotracheal tube can be used to detect an obstruction. Further studies are needed for clinical application.
