This is an observational study. We use electronic stethoscope, which stick on patient's anterior chest, to record breath sound after intubation. The soundtrack will then be transformed to visualized waveform, enabling us to analyze and compare with actual result confirmed by fiberscope.
In modern thoracic surgery, double-lumen endobronchial tube (DLET) is the first choice for intubation. One lung ventilation can be perfectly performed by DLET, with the benefit of maintaining adequate gas exchange and establishing great surgical field. Traditionally, we use stethoscope and fiberscope for DLET site evaluation. However, there are some concerns over traditional methods. Stethoscope evaluation can be subjective from person to person; fiberscope, on the other hand, can cause additional bronchial injury as it is an invasive procedure. We hope to utilize patches, also known as electronic stethoscope, which provide non-invasive and visualized spectrum information, to assist anesthesiologists evaluate DLET insertion site more precisely in patients undergo thoracic surgery.