Unconstrained monitoring of long-term heart and breath rates during sleep

Physiol Meas. 2008 Feb;29(2):N1-10. doi: 10.1088/0967-3334/29/2/N01. Epub 2008 Jan 14.

Abstract

An unconstrained method for the long-term monitoring of heart and breath rates during sleep is proposed. The system includes a sensor unit and a web-based network module. The sensor unit is set beneath a pillow to pick up the pressure variations from the head induced by inhalation/exhalation movements and heart pulsation during sleep. The measured pressure signal was digitized and transferred to a remote database server via the network module. A wavelet-based algorithm was employed to detect the heart and breath rates, as well as body movement, during sleep. The overall system was utilized for a total six-month trial operation delivered to a female subject. The profiles of the heart and breath rates on a beat-by-beat and daily basis were obtained. Movements during sleep were also estimated. The results show that the daily average percentage of undetectable periods (UPs) during 881.6 sleep hours over a 180 day period was 17.2%. A total of 89.2% of sleep hours had a UP of not more than 25%. The profile of the heart rate revealed a periodic property that corresponded to the female monthly menstrual cycle. Our system shows promise as a long-term unconstrained monitor for heart and breath rates, and for other physiological parameters related to the quality of sleep and the regularity of the menstrual cycle.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Diagnosis, Computer-Assisted / instrumentation*
  • Diagnosis, Computer-Assisted / methods
  • Electrocardiography / instrumentation*
  • Female
  • Heart Rate / physiology*
  • Humans
  • Internet / instrumentation
  • Manometry / instrumentation
  • Manometry / methods
  • Monitoring, Ambulatory / instrumentation
  • Monitoring, Ambulatory / methods
  • Polysomnography / instrumentation*
  • Polysomnography / methods
  • Reference Values
  • Respiratory Mechanics / physiology*
  • Sleep / physiology*
  • Telemedicine / instrumentation*
  • Transducers