CO2 production and breathing pattern during invasive and non-invasive respiratory monitoring.
A computerized non-invasive strain gauge system for respiratory monitoring is described and compared with pneumotachography. With the use of simultaneous capnography, changes in breathing pattern, end-tidal PCO2 and CO2 production were evaluated during non-invasive (NIM) and invasive breathing monitoring (IM) in 14 healthy subjects. An overall absolute difference between measured and calculated tidal volumes of 4.6 +/- 3.47% (r = 0.97) was found. When switching from NIM to IM, tidal volume increased by 19% and breathing frequency decreased by 11% with a 10% increase in minute ventilation. These changes were mainly accomplished by an increased respiratory drive with the timing component unaltered. During IM both end-tidal PCO2 and CO2 production increased significantly as compared with those during NIM.
D000328:Adult; D002245:Carbon Dioxide / Q000032:analysis*; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic; D012119:Respiration; D012129:Respiratory Function Tests / Q000295:instrumentation / Q000379:methods; D013990:Tidal Volume
D002245:Carbon Dioxide