Correlation of PaCO2 to the Inspired and Expired Oxygen Gradient

Correlation of PaCO2 to the Inspired and Expired Oxygen Gradient

The purpose of this study is to evaluate whether a correlation exists between the partial pressure of carbon dioxide existing within arterial blood and the gradient between inhaled and exhaled fractions of oxygen.

Inclusion Criteria:

• Age 18 to 65.
• Scheduled for surgical procedure that will last at least 2 hours.
• Arterial cannulation is planned because of either the complexity of the surgery or patient comorbidity.
• At least two arterial blood gas analyses are planned during the surgery.

Exclusion Criteria:

• No arterial cannulation is necessary or planned for the procedure.