An improved rebreathing method for measuring mixed venous carbon dioxide tension and its clinical application.

The mixed venous carbon dioxide tension (PVCO2) can be measured at the bedside by a rebreathing equilibrium technique that is quick, simple and noninvasive. Only one brief period of rebreathing is required. The technique is accurate even when the lungs are not normal, and gives a graphic record that allows verification of the accuracy of the estimate. The PVCO2 is affected mainly by changes in alveolar ventilation and cardiac output. It can be …