A single indicator technique to estimate extravascular lung water.
An estimate of extravascular thermal volume (EVTV) calculated from a single thermal indicator (SI) sampled in the pulmonary artery and the femoral artery was compared with direct gravimetric measurements of extravascular lung water (EVLW) on 47 dogs and with simultaneous double indicator (DI) dilution measurements made on 62 dogs and 38 humans with heat as the diffusible indicator and green dye as the intravascular indicator. For the gravimetric measurements the relation was EVTV(SI) = 1.00 EVLW(grav) + 61 ml r = 0.91. When compared with double indicator dilution measurements, the results were EVTV(SI) = 1.10 EVTV(DI) + 17 ml r = 0.94 for dogs and EVTV(SI) = 0.89 EVTV(DI) + 66 ml r = 0.97 for humans. A total of 1880 measurements were made over a range of EVTV(DI) from 70 to 2150 ml. The single indicator measurements of EVTV agrees with the double indicator measurements of EVTV and with the direct gravimetric measurements of EVLW and can be performed with standard catheters and without the withdrawal of blood.
D000818:Animals; D001810:Blood Volume; D004285:Dogs; D005110:Extracellular Space / Q000032:analysis*; D006321:Heart / Q000502:physiology; D006801:Humans; D007201:Indicator Dilution Techniques; D007202:Indicators and Reagents; D008168:Lung / Q000502:physiology*; D008176:Lung Volume Measurements / Q000379:methods*; D011651:Pulmonary Artery / Q000502:physiology; D013815:Thermodilution
D007202:Indicators and Reagents