Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
2 Pt 2
|
| pubmed:dateCreated |
1989-3-23
|
| pubmed:abstractText |
We previously found limited tolerance to acute reduction in cardiac output in lambs at the nadir of their physiological anemia [Am. J. Physiol. 253 (Heart Cir. Physiol. 12): H100-H106, 1987]. To determine the effect of hemoglobin concentration [Hb] on critical cardiac output, critical systemic O2 transport, and peripheral O2 extraction, we performed 31 experiments in 12 one-mo-old lambs at four [Hb] (means +/- SD in g/dl): 7.4 +/- 0.6, 10.5 +/- 0.5, 14.5 +/- 0.5, and 16.5 +/- 0.6. Desired [Hb] was obtained by exchange transfusion with packed red cells or plasma. Cardiac output was reduced by inflation of a balloon-tipped catheter in the right atrium, and critical levels were defined at the point where O2 consumption decreased and/or arterial blood lactate concentration increased in response. With lower [Hb], cardiac output was unchanged, systemic O2 transport was reduced, and fractional O2 extraction was increased, keeping O2 consumption constant at base line. As [Hb] was reduced, critical cardiac output was significantly higher, whereas critical systemic O2 transport was independent of [Hb], as were fractional O2 extraction and mixed venous PO2 at the critical point. Thus peripheral O2 extraction was not affected by changes in [Hb] during progressive decreases in cardiac output. We conclude that 4-wk-old lambs have decreased tolerance to reductions in cardiac output and systemic O2 transport because their relative anemia provides them with a base-line cardiac output and systemic O2 transport close to the critical level.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Feb
|
| pubmed:issn |
0002-9513
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
256
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
H527-32
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:2916686-Animals,
pubmed-meshheading:2916686-Cardiac Output,
pubmed-meshheading:2916686-Hemoglobins,
pubmed-meshheading:2916686-Lactates,
pubmed-meshheading:2916686-Oxygen,
pubmed-meshheading:2916686-Oxygen Consumption,
pubmed-meshheading:2916686-Partial Pressure,
pubmed-meshheading:2916686-Sheep
|
| pubmed:year |
1989
|
| pubmed:articleTitle |
Effect of hemoglobin concentration on critical cardiac output and oxygen transport.
|
| pubmed:affiliation |
Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06510.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|