Abstract
Several indicator dilution techniques are described for the measure of anatomic shunting. During breath-holding, three of 20 in vitro lungs demonstrated a xenon-133 dilution curve which could be readily separated into a slow and rapid component. The slow component corresponded to the air volume contained in the lung. The rapid component described the anatomic shunt since its transit time was equivalent to the intravascular reference tracer. Secondly, the area described by this component was similar to, although somewhat lower than, the xenon-133 area measured during breathing. The fractional xenon area, or recovery during breathing, was in accord with oxygen measured QS Q. Both measurements tended to overestimate anatomic shunting because of the contribution of low va q ratios to gas recoveries. Gas solubility was an important factor in determining this error which occurred even when QS Q was measured during 100 percent oxygen breathing. In addition, if the lungs functioned as a multicompartmental system, tracer recovery was increased beyond that predicted by a single-compartment model. A two-compartment system is offered as a practical method of measuring anatomic shunting. The use of two gases, xenon-133 and krypton-85, led to calculated shunts which were significantly lower than those measured during inhalation of 100 percent oxygen. The measurements may be done during breathing, without control of the airway.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 443-450 |
| Number of pages | 8 |
| Journal | Surgery |
| Volume | 72 |
| Issue number | 3 |
| State | Published - 1972 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Surgery
- Medicine(all)
Cite this
Shunting in the lung : A two-compartment model. / Hechtman, Herbert B.; Reid, Michael H; Dorn, Barry C.; Justice, Richard E.; Weisel, Richard D.
In: Surgery, Vol. 72, No. 3, 1972, p. 443-450.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Shunting in the lung
T2 - A two-compartment model
AU - Hechtman, Herbert B.
AU - Reid, Michael H
AU - Dorn, Barry C.
AU - Justice, Richard E.
AU - Weisel, Richard D.
PY - 1972
Y1 - 1972
N2 - Several indicator dilution techniques are described for the measure of anatomic shunting. During breath-holding, three of 20 in vitro lungs demonstrated a xenon-133 dilution curve which could be readily separated into a slow and rapid component. The slow component corresponded to the air volume contained in the lung. The rapid component described the anatomic shunt since its transit time was equivalent to the intravascular reference tracer. Secondly, the area described by this component was similar to, although somewhat lower than, the xenon-133 area measured during breathing. The fractional xenon area, or recovery during breathing, was in accord with oxygen measured QS Q. Both measurements tended to overestimate anatomic shunting because of the contribution of low va q ratios to gas recoveries. Gas solubility was an important factor in determining this error which occurred even when QS Q was measured during 100 percent oxygen breathing. In addition, if the lungs functioned as a multicompartmental system, tracer recovery was increased beyond that predicted by a single-compartment model. A two-compartment system is offered as a practical method of measuring anatomic shunting. The use of two gases, xenon-133 and krypton-85, led to calculated shunts which were significantly lower than those measured during inhalation of 100 percent oxygen. The measurements may be done during breathing, without control of the airway.
AB - Several indicator dilution techniques are described for the measure of anatomic shunting. During breath-holding, three of 20 in vitro lungs demonstrated a xenon-133 dilution curve which could be readily separated into a slow and rapid component. The slow component corresponded to the air volume contained in the lung. The rapid component described the anatomic shunt since its transit time was equivalent to the intravascular reference tracer. Secondly, the area described by this component was similar to, although somewhat lower than, the xenon-133 area measured during breathing. The fractional xenon area, or recovery during breathing, was in accord with oxygen measured QS Q. Both measurements tended to overestimate anatomic shunting because of the contribution of low va q ratios to gas recoveries. Gas solubility was an important factor in determining this error which occurred even when QS Q was measured during 100 percent oxygen breathing. In addition, if the lungs functioned as a multicompartmental system, tracer recovery was increased beyond that predicted by a single-compartment model. A two-compartment system is offered as a practical method of measuring anatomic shunting. The use of two gases, xenon-133 and krypton-85, led to calculated shunts which were significantly lower than those measured during inhalation of 100 percent oxygen. The measurements may be done during breathing, without control of the airway.
UR - http://www.scopus.com/inward/record.url?scp=0015402764&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0015402764&partnerID=8YFLogxK
M3 - Article
C2 - 4559298
AN - SCOPUS:0015402764
VL - 72
SP - 443
EP - 450
JO - Surgery (United States)
JF - Surgery (United States)
SN - 0039-6060
IS - 3
ER -