Cardiopulmonary changes induced during one-lung ventilation in anesthetized dogs with a closed thoracic cavity.
OBJECTIVE
To evaluate the effects of one-lung ventilation (OLV) on oxygen delivery (DO2) in anesthetized dogs with a closed thoracic cavity.


METHODS
7 clinically normal adult Walker Hound dogs.


METHODS
Dogs were anesthetized. Catheters were inserted in a dorsal pedal artery and the pulmonary artery. Dogs were positioned in right lateral recumbency. Data were collected at baseline (Paco2 of 35 to 45 mm Hg), during two-lung ventilation, and 15 minutes after creating OLV. Hemodynamic and respiratory variables were analyzed and calculations performed to obtain DO2, and values were compared among the various time points by use of an ANOVA for repeated measures.


RESULTS
OLV induced a significant augmentation of shunt fraction that resulted in a significant reduction in Pao2, arterial oxygen saturation, and arterial oxygen content. Cardiac index was not significantly changed. The net result was that DO2 was not significantly affected by OLV.


CONCLUSIONS
Use of OLV in healthy dogs does not induce significant changes in DO2, which is the ultimate variable to use when evaluating tissue oxygenation. One-lung ventilation can be initiated safely in dogs before entering the thoracic cavity during surgery. Additional studies are necessary to evaluate OLV in clinically affected patients and variations in age, body position, and type of anesthetic protocol.
Riquelme
Miriam
M
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523-1601, USA.
Monnet
Eric
E
Kudnig
Simon T
ST
Gaynor
James S
JS
Wagner
Ann E
AE
Corliss
Denise
D
Salman
M D
MD
D000704:Analysis of Variance; D000771:Anesthesia, Intravenous / Q000662:veterinary*; D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D004285:Dogs / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D008168:Lung / Q000502:physiology*; D010100:Oxygen / Q000008:administration & dosage / Q000097:blood*; D012123:Pulmonary Ventilation / Q000502:physiology*; D012121:Respiration, Artificial / Q000379:methods / Q000662:veterinary*
D010100:Oxygen