Continuous monitoring of blood gases during hypercapnia in a patient with severe acute lung failure.

We report about our first experiences with a new device for continuous intra-arterial monitoring of blood gases in a patient with severe acute respiratory failure. This device facilitated continuous monitoring of PaO2, PaCO2 and pH while weaning the patient from extracorporeal membrane oxygenation (ECMO). Although sufficient oxygenation at FIO2 0.45 could be achieved after disconnection from ECMO, carbon dioxide elimination remained inadequate and resulted in severe respiratory acidosis. Within six hours, PaCO2 increased to 95 mmHg. Continuous monitoring of pH and PaCO2 helped to monitor CO2 retention and assisted the decision making process for reinstitution of ECMO.