Abstract
1. Two adult merino ewes were prepared with intravascular cannule for sampling aortic root blood, sagittal sinus blood and coronary sinus blood. 2. One week after preparation the animals were anaesthetized then ventilated with a gas mixture containing 10% nitrous oxide (N2O) for 60 min. Serial measurements of brain and myocardial blood flow were made using the N2O tissue equilibration method of Kety and Schmidt. 3. N2O failed to achieve matching arteriovenous blood concentration equality and saturation of the relevant tissues. Valid use of the Kety‐Schmidt method, therefore, could not be confirmed. 4. Because of the failure of the arteriovenous equilibration, serially determined brain and myocardial blood flows were found to decrease with time. 5. The use of this method in circumstances where tissue saturation with the indicator gas cannot be ascertained is arbitrary.
Original language | English |
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Pages (from-to) | 229-233 |
Number of pages | 5 |
Journal | Clinical and Experimental Pharmacology and Physiology |
Volume | 19 |
Issue number | 4 |
DOIs | |
Publication status | Published or Issued - Apr 1992 |
Externally published | Yes |
Keywords
- blood concentrations analysis
- brain
- cardiovascular system
- myocardium
- nitrous oxide
- pharmacokinetics
- regional blood flow
- sheep
ASJC Scopus subject areas
- Physiology
- Pharmacology
- Physiology (medical)