title: System for simultaneously monitoring heart and breathing rate in mice using a piezoelectric transducer.
abstract: We propose a novel system for simultaneously monitoring the heart rate (HR) and breathing rate (BR) of anesthetized mice using a piezoelectric transducer (PZT) placed under the body. It is known that a PZT, which transforms mechanical vibrations into electrical signals, can detect heart sounds and breathing movements. However, no PZT system has been reported for simultaneous and continuous monitoring of HR and BR, possibly due to difficulties in eliminating noises and errors caused by the amplitude fluctuation of heart sounds and breathing movements. These difficulties were overcome by custom-designed analogue circuitry and a microprocessor program, resulting in detection of HR and BR with a high reliability compared to the values obtained from ECG and a conventional airflow sensor. We believe that this practical and easy-to-use system can be applied to a wide variety of basic and clinical research fields.
authors.affiliation: Department of Physiology, Akita University School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan. bigwave@gipc.akita-u.ac.jp
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sato
authors.forename: Katsuya
authors.initials: K
authors.lastname: Yamada
authors.forename: Nobuya
authors.initials: N
authors.lastname: Inagaki
mesh_terms: D000465:Algorithms; D000818:Animals; D006339:Heart Rate; D006347:Heart Sounds; D051379:Mice; D008838:Microcomputers; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods; D015656:Respiratory Mechanics; D012815:Signal Processing, Computer-Assisted; D014159:Transducers