Download PDF
Methods Inf Med 1983; 22(04): 198-203
DOI: 10.1055/s-0038-1635436
Original Artical
Schattauer GmbH

Continuous Monitoring of Respiratory Variables During Sleep by Microcomputer

Fortlaufende Beobachtung Von Atmungsvariablen Während Des Schlafes Mit Hilfe Eines Mikrocomputers
P. West
1   From the St. Boniface General Hospital, Department of Respiratory Medicine, Winnipeg, Canada
,
M. H. Kryger
1   From the St. Boniface General Hospital, Department of Respiratory Medicine, Winnipeg, Canada
› Author Affiliations
Further Information

Publication History

Publication Date:
20 February 2018 (online)

    Permissions and Reprints

A microcomputer system has been developed to acquire, process and store respiratory and heart rate data for all-night sleep studies. Signals monitored continuously are: expired carbon dioxide (an index of airflow); respiratory inductance plethysmography (an index of the volume of air exchanged); oxygen saturation; and heart rate. The respiratory inductance Plethysmograph signal is reduced to a set of values which summarize each complete respiratory cycle (inspiratory time, expiratory time, and tidal volume index). Values of oxygen saturation and heart rate are saved at two points: the onset of inspiration and expiration. These signals, and derived values, are continuously updated on the system video display terminal. An audible alarm signals the presence of apneic events, and defects in the computer-polygraph interface. The software identifies three forms of apnea (central, obstructive, and mixed) in accordance with conventional definitions. A continuous polygraphic recording is time-synchronized, by a software generated time-coded signal, to enable the subsequent incorporation of the manually reduced sleep stage data. The sleep stage distribution data is placed, under program control, on the same storage medium as the computer-acquired data. Statistical relationships between sleep stage and respiration are investigated.

Ein Mikrocomputersystem wurde entwickelt, um Atmungs- und Herzfrequenzdaten für Studien über den Nachtschlaf zu erheben, zu verarbeiten und zu speichern. Fortlaufend beobachtete Signale sind: ausgeatmetes Kohlendioxyd (ein Hinweis auf den Luftstrom), respiratorische Induktionsplethysmographie (ein Maß für den Gasaustausch), Sauerstoffsättigung und Herzfrequenz. Die respiratorische Induktionsplethysmographie wird auf eine Anzahl von Werten eingeschränkt, welche jeden vollständigen Atmungszyklus (Inspirationszeit, Exspirationszeit und Atmungsvolumenindex) zusammenfassen. Werte für Sauerstoffsättigung und Herzfrequenz werden an zwei Punkten festgehalten: dem Beginn der Inspirationsphase und dem Beginn der Exspirationsphase. Diese Signale und davon abgeleitete Werte werden auf dem Bildschirm des Systems fortlaufend aktualisiert. Ein Warnton signalisiert das Vorliegen von Phasen von Apnoe und Fehler zwischen Computer und Mehrkanalschreiber. Die Software erkennt drei Formen von Apnoe (zentrale, obstruktive und kombinierte Formen) gemäß den konventionellen Definitionen. Eine fortlaufende Aufzeichnung mit Mehrkanalschreiber wird durch ein softwareerzeugtes Zeitsignal zeitlich synchronisiert, um die nachfolgende Einbeziehung der manuell reduzierten Daten über das Schlafstadium zu ermöglichen. Daten über die Verteilung der Schlafstadien werden unter Programmkontrolle auf dasselbe Speichermedium wie die computererhobenen Daten eingebracht. Die statistischen Beziehungen zwischen Schlafstadium und Atmung werden untersucht.

Key-Words

Sleep - Breathing - Sleep Apnea - Microcomputer

Schlüssel-Wörter

Schlaf - Atmung - Apnoe während des Schlafes - Mikrocomputer
 

  • References

  • 1 BROWNELL L. G., West P., Sweatman P., Acres J. C, Kryger M. H.. Protriptyline in obstructive sleep apnea: A double blind trial. New Engl. J. Med 1981; 307: 1037-1042.
    PubMedGoogle Scholar
  • 2 CHADRA T. S., Watson H., Birch S., Jenouri G. A., Schneider A. W., Cohn M. A., Sackner M. A.. Validation of respiratory inductance plethysmography using different calibration procedures. Amer. Rev. respir. Dis 1982; 125: 644-649.
    PubMedGoogle Scholar
  • 3 Cohn M. A., Rao A. S. V., Broudy M., Birch S., Watson H., Atkins N., Davis B., Stott F. D., Sackner M. A.. The respiratory inductance Plethysmograph: A new noninvasive monitor for respiration. Bull. Europ. physiopath. Resp 1982; 18: 643-658.
    PubMedGoogle Scholar
  • 4 Digital Equipment Corporation: Laboratory subroutines programmer’s reference manual. A-C984C-TC, Chapter 2. (Marlboro, Massachusetts, October. 1981
    PubMedGoogle Scholar
  • 5 Douglas N. J., Leggett R. J. E., Calverley P. M. A., Brash H. M., Flenley D. C, Brezinova V.. Transient hypoxaemia during sleep in chronic bronchitis and emphysema. Lancet 1979; I 1-4.
    PubMedGoogle Scholar
  • 6 Flemister C, Goldberg N. B., Sharp J. T.. Dysrhyth-mic breathing. Chest 1981; 79: 33-38.
    PubMedGoogle Scholar
  • 7 Gothe B., Goldman M. D., Cherniak N. S., Mantey P.. Effect of progressive hypoxia on breathing during sleep. Amer. Rev. respir. Dis 1982; 126: 97-102.
    PubMedGoogle Scholar
  • 8 Guilleminault C, van den Hoed J., Mitler M. M.. Clinical overview of the sleep apnea syndromes. In Guilleminault C, Dement W. C.. (Eds) Sleep Apnea Syndromes. pp 1-12. New York: Alan R. Liss; 1978
    Google Scholar
  • 9 Haddad G. G., Epstein R. A., Epstein M. A. F., Leistner H. L., Marino P. A., Mellins R. B.. Maturation of ventilation and ventilatory pattern in normal sleeping infants. J. appl. Physiol. Respirat. Environ. Exerc. Physiol 1979; 46: 998-1002.
    PubMedGoogle Scholar
  • 10 Hoppenbrouwers T., Hodgman J. E., McGinty D., Harper R. M., Sternman M. B.. Sudden infant death syndrome: Sleep apnea and respiration in subsequent siblings. Pediatrics 1980; 66: 205-214.
    PubMedGoogle Scholar
  • 11 Kryger M., Bode F., Antic R., Anthonisen N.. Diagnosis of obstruction of the upper and central airways. Amer. J. Med 1976; 61: 85-93.
    CrossrefPubMedGoogle Scholar
  • 12 Laxminarayan S., Mills O., Costigan E. F., Cornwell A. C, Chatterjee S., Weitzman E. D.. On-line respiratory monitoring in SIDS using a mini computer. Frontiers of Engineering in Health Care, IEEE 1980; pp. 38-41. In: Proceed. 3rd Ann. Conf. Engineering in Medicine and Biology Society, Institute of Electrical and Electronics Engineers.
    PubMedGoogle Scholar
  • 13 Lugaresi E., Coccagna G., Mantovani M.. Effect of tracheostomy in two patients with hypersomnia and periodic breathing. J. Neurol. Neurosurg. Psychiatry 1973; 36: 15
    CrossrefPubMedGoogle Scholar
  • 14 Mezon B. L., West P., Israels J., Kryger M.. Sleep breathing abnormalities in kyphoscoliosis. Amer. Rev. respir. Dis 1980; 122: 617-621.
    PubMedGoogle Scholar
  • 15 Organek H., Lopata M., Onal E.. Comparison of tidal volume measured by magnetometer, respiratory inductance plethysmography, and pneumotachograph. Amer. Rev. respir. Dis 1982; 125: 239
    PubMedGoogle Scholar
  • 16 Rechtschaffen A., Kales A.. A manual of standardized terminology, techniques, and scoring system for sleep stages of human subjects. Washington, D. C: National Institute of Health Publications No. 204; 1968
    Google Scholar
  • 17 Smith J. R.. Computers in sleep research. CRC Crit. Rev. Bioeng 1978; 3: 93-148.
    PubMedGoogle Scholar
  • 18 Tabachnik E., Muller N. L., Bryan A. C, Levison H.. Changes in ventilation and chest wall mechanics during sleep in normal adolescents. J. appl. Physiol. Respirat. Environ. Exerc. Physiol 1981; 51: 557-564.
    PubMedGoogle Scholar
  • 19 Tabachnik E., Muller N. L., Levison H., Bryan A. C. Chest wall mechanics and pattern of breathing during sleep in asthmatic adolescents. Amer. Rev. respir. Dis 1981; 124: 269-273.
    PubMedGoogle Scholar
  • 20 Watson H., Schneider A., Friden A., Sackner M. A.. Continuous non-invasive microprocessor measurement of respiration. Amer. Rev. respir. Dis 1980; 121: 203
    PubMedGoogle Scholar
  • 21 Zimmerman P. V., Connellan H. C, Middleton H. C, Tabona M. V., Goldman M. D., Pride N. B.. Postural changes in rib cage and abdominal motion coefficients and their effect on the calibration of a respiratory inductance Plethysmograph. Amer. Rev. respir. Dis 1981; 123: 211
    PubMedGoogle Scholar