The use of tracheal sounds for the diagnosis of sleep apnoea

Abstract

Tracheal sounds have been the subject of many research studies. In this review, we describe the state of the art, original work relevant to upper airways obstruction during sleep, and ongoing research concerning the methods used when analysing tracheal sounds. Tracheal sound sensors are a simple and noninvasive means of measurement and are more reliable than other breathing sensors. Developments in acoustic processing techniques and enhancements in tracheal sound signals over the past decade have led to improvements in the accuracy and clinical relevance of diagnoses based on this technology. Past and current research suggests that they may have a significant role in the diagnosis of obstructive sleep apnoea.Key pointsTracheal sounds are currently a topic of significant interest but are not yet used in most routine sleep study systems.Measured at the suprasternal notch, tracheal sounds can provide reliable information on breathing sounds, snoring sounds and respiratory efforts.Tracheal sounds may be used as a noninvasive method of studying abnormalities of the upper airways during wakefulness.Educational aimsTo understand the principles of tracheal sound measurement and analysis.To highlight the importance of tracheal sounds for the diagnosis of sleep apnoea–hypopnoea syndrome.To present the most relevant clinical studies that have validated the use of tracheal sound sensors and to make future clinical validation studies possible.

Breathing detection from tracheal sounds in both temporal and frequency domains in the context of phrenic nerve stimulation

“…FFT is applied on each segment with Hanning window (R seg (k)). Depending on the recording device, the main respiratory frequency band could be different [22]. In this study, as shown in Fig.…”

Tracheal sound analysis for detection of sleep disordered breathing

“…TS signals correlate well with respiratory flow, with no significant difference in the number of apneas detected with TS or reference sensors [4,[6][7][8][9]. Tracheal sounds, recorded at the sternal notch, reflect the superficial vibrations of the body setinmotionbypressure fluctuations [10,11]. Placed on the sternal notch, the TS sensors can detect these vibrations and thus measure tracheal flow sound as well as snoring.…”

Journal of Clinical Monitoring and Computing 2018–2019 end of year summary: respiration

“…The authors' note that the algorithm's performance of 92% sensitivity and 98% specificity exceeds that of a piezo-electric film based acoustic method reported in the literature. Using tracheal sounds for apnea detection is an area of increased research and commercial interest, particularly with respect to the detection of sleep apnea [15].…”