[Capnometry. Technique and clinical use in anesthesia and emergency medicine]

By capnometry is understood measurement of carbon dioxide in the expiratory air. The concentration can be determined by various forms of spectometry. A new acoustic principle of measurement is more sensitive than the methods hitherto employed. Capnometry registers rapid intubation of the oesophagus. Sudden changes in expired carbon dioxide may be signs of malignant hyperthermia or pulmonary embolism. In addition, capnometry is a valuable aid in the regulation of mechanical ventilation. Recent investigations suggest that capnometry can be employed to confirm or refute clinical suspicion of pulmonary embolism and that measurement of expired carbon dioxide may be of prognostic value in resuscitation. It has not yet be elucidated whether nasal measurements in patients who are not intubated can provide reliable values.