[The reduction of anesthetic risk by high frequency jet ventilation during endobronchial cryotherapy]. / Réduction du risque anesthésique par la jet ventilation à haute fréquence lors de la cryothérapie endobronchique.

Endotracheal cryotherapy was performed in 22 ASA III or IV patients with inoperable carcinoma. All patients received propofol by continuous infusion and fentanyl by bolus. In 11 patients (SV group) ventilation remained spontaneous. In 11 patients (HFJV group) high frequency jet ventilation was used with air-CO2 (1:1). Respiratory and haemodynamic parameters were studied and compared in the two groups. Systolic blood pressure was slightly and transiently lower in the HFJV group. In this group PaCO2 remained excellent during the whole procedure, in SV group hypoxemia was constant. PaCO2 increased in both groups but very shortly in the HFJV group. Several arrhythmias and other transient adverse effects occurred in the SV group, none in the HFJV group. Thus clinical and haemodynamic tolerance of HFJV seem excellent. HFJV appears to be a very secure method for difficult endoscopic procedures.