2003 OPEN FORUM Abstracts
RELIABILITY OF OXYGENATION INDICES AFTER OPEN HEART SURGERIES
Mohamad El-Khatib, PhD, RRT, Department of Anesthesiology - American
University of Beirut, Lebanon and Robert Chatburn, RRT-NPS, FAARC,
University Hospitals of Cleveland, OH
Background: Various oxygenation indices have been proposed in the literature as substitutes for a true shunt measurement. These indices do not contain information related to the level of mechanical ventilation, so may not be as accurate as possible in some patients. The purpose of this study was to assess the reliability of two new indices compared to traditional oxygenation measurements in reflecting the intrapulmonary shunt for patients being ventilated after cardiac surgery.
Methods: A convenience sample was taken of patients in a university hospital who were being ventilated after coronary artery bypass grafting. Simultaneous blood samples were collected from an indwelling arterial line and a Swan-Ganz catheter for determination of blood gases. Each index was compared to the standard shunt index using the Pearson Product Moment Correlation Coefficient. Significance was set at p = 0.05.
Results: Fifty-five patients were studied. Shunt values ranged from 1% to 20%. All correlations were significantly different from zero. Data in the table below are given as mean ± standard deviation:
Conclusion: In this group of patients, both of the new oxygenation indices, and were more reliable than other oxygenation measurements in reflecting intrapulmonary shunt. Inclusion of ventilator related information (mean airway pressure and ) may be responsible for the greater accuracy. 2 CO Pa