Evaluation of the Respiratory Function in Intensive Care: Prospects and Hopes in Medical Instrumentation

Respiratory function assessment involves various measuring techniques. At a fundamental level, the repeated determination of blood gases provides a monitoring of the overall pulmonary and circulatory performance. The analysis of the respiratory gas composition, PCO2 in particular, brings up complementary data in the evaluation of the respiratory function. Pulmonary mechanics investigations give informations directly related to the pathological mechanics involved in the respiratory failure. Progresses in intensive care instrumentation allow to outline possible future trends in the monitoring of the respiratory function: the continuous measurement of the blood gases, Pa02, PaCO2, pH and the blood electrolytes, appears now as a realistic perspective. The developpement of the microelectronic technology has permitted the implementation of multiple sensors which can be fitted in a catheter. Similarity, various types of gas sensors are being designed, which promote a more frequent use of the modern ventilation control techniques. Finally, the high frequency acoustical respiratory impedance opens new perspectives in the pulmonary mechanics evaluation at the bedside.