ICU Monitoring of Ventilation Distribution

  • Richard R. Mitchell
  • Ross M. Wilson
  • Dianne Sierra


Routine monitoring of lung volume in mechanically ventilated patients may be useful for detecting the onset of atelectasis, pulmonary edema, pneumothorax, and mucous plug airway obstruction. The oxygen eashin method was developed to monitor FRC in the intensive care unit(ICU)1. Fast and slow space components were observed in normalized semilogarithmic plots of mixed expired O2 fraction following changes in the ventilator inspired O2 fraction for ventilators with small internal mixing volumes2. This suggested the possibility of obtaining estimates of ventilation and volume in a two compartment model of the lung and a detailed digital computer simulation showed no significant difference between estimates of two compartment parameters using O2 washin or N2 washout data3.


Dead Space Ventilation Mode Peep Level Oxygen Fraction Leftward Shift 
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Copyright information

© Plenum Press, New York 1983

Authors and Affiliations

  • Richard R. Mitchell
    • 1
  • Ross M. Wilson
    • 1
  • Dianne Sierra
    • 1
  1. 1.The Institute of Biomedical Engineering SciencesThe Institutes of Medical SciencesSan FranciscoUSA

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