Carbon dioxide monitoring during high-frequency jet ventilation for rigid bronchoscopy

At present, high-frequency jet ventilation (HFJV) is a common and well-accepted method of ventilation during laser therapy performed using a rigid bronchoscope [1]. The ability of jet ventilation to maintain an adequate oxygenation and to provide an effective CO2 elimination during operative procedures, allowing the bronchoscopist satisfactory operating conditions, is well known [2]. Oxygenation of the patient can be monitored in an easy way by means of a pulse oximetry (measurement of SpO2); carbon dioxide monitoring is more difficult to evaluate and requires adequate equipment [3]. The aim of this study was to assess the reduction of transcutaneous CO2 partial pressure, as an approximation for PaCO2, measured by a new noninvasive technique at the ear lobe during progressive changes of the driving pressure (DP).