Effect of one-lung ventilation on oxygen delivery in anesthetized dogs with an open thoracic cavity.
OBJECTIVE
To evaluate effects of one-lung ventilation on oxygen delivery in anesthetized dogs with an open thoracic cavity.


METHODS
8 clinically normal adult Walker Hound dogs.


METHODS
Each dog was anesthetized and subjected to one-lung ventilation during a period when it had an open thoracic cavity. A Swan-Ganz catheter was used to measure hemodynamic variables and obtain mixed-venous blood samples. A catheter was inserted in the dorsal pedal artery to measure arterial pressure and obtain arterial blood samples. Oxygen delivery index was calculated and used to assess effects of one-lung ventilation on cardiopulmonary function. Effects on hemodynamic and pulmonary variables were analyzed.


RESULTS
One-lung ventilation caused significant decreases in PaO2, arterial oxygen saturation (SaO2), mixed-venous oxygen saturation, and arterial oxygen content (CaO2). One-lung ventilation caused significant increases in PaCO2, physiologic dead space, and alveolar-arterial oxygen difference. Changes in SaO2, CaO2, and PaCO2, although significantly different, were not considered to be of clinical importance. One-lung ventilation induced a significant increase in pulmonary arterial wedge pressure, mean pulmonary artery pressure, and shunt fraction. One-lung ventilation did not have a significant effect on cardiac index, systemic vascular resistance index, pulmonary vascular resistance index, and oxygen delivery index.


CONCLUSIONS
One-lung ventilation affected gas exchange and hemodynamic function, although oxygen delivery in clinically normal dogs was not affected during a period with an open thoracic cavity. One-lung ventilation can be used safely in healthy dogs with an open thoracic cavity during surgery.
Kudnig
Simon T
ST
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
Monnet
Eric
E
Riquelme
Miriam
M
Gaynor
James S
JS
Corliss
Denise
D
Salman
M D
MD
D000769:Anesthesia, Inhalation; D000818:Animals; D001784:Blood Gas Analysis; D004285:Dogs; D005260:Female; D006439:Hemodynamics; D008168:Lung / Q000502:physiology*; D008297:Male; D010100:Oxygen / Q000097:blood / Q000378:metabolism*; D012121:Respiration, Artificial / Q000379:methods* / Q000662:veterinary*; D035423:Thoracic Cavity / Q000502:physiology / Q000601:surgery*; D019616:Thoracic Surgical Procedures / Q000662:veterinary
D010100:Oxygen