Effects of Limited Movement on the Impedance Plethysmograph Signal: A preliminary Study

Abstract

The impedance plethysmograph was evaluated as a means of monitoring respiration of personnel in a space-flight environment. Emphasis was placed on studying the effects of limited movement (tapping of electrodes and skin stretching) on the impedance plethysmograph signal. A bridge circuit and servospirometer were used to make extremely sensitive measurements of body impedance change and tidal volume. The linear relationship between tidal volume and thoracic impedance was determined by analog and digital methods. These methods were also used to investigate the amount of interference caused by various body movements on the impedance signal. Possible ways of eliminating error from such artifacts were also studied. Very high linear correlation (r = . 85 to .95) was obtained using a bridge circuit. The effects of artifact were reduced by the use of analog filtering, digital programming technics, and a careful choice of display.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1970
Accession Number
AD0715211

Entities

People

  • John W. Yates

Organizations

  • United States Air Force School of Aerospace Medicine

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Aerospace Medicine
  • Air Force
  • Data Processing
  • Detectors
  • Digital Data
  • Electrical Impedance
  • Electrical Properties
  • Electrocardiography
  • Frequency
  • Impedance
  • Measurement
  • Monitoring
  • Regression Analysis
  • Resistance
  • Respiration
  • Space Flight
  • Standards

Readers

  • Electrical Engineering
  • Exercise and Sports Science.
  • Systems Analysis and Design

Technology Areas

  • Space