Vaporizer for volatile anesthetics during high-frequency jet ventilation

At present, the potent inhalation anesthetics cannot be used during high-frequency jet ventilation (HFJV) because a suitable vaporizer is not available. A vaporizer for enflurane during HFJV was designed, built, and tested, based on the principle of airblast atomization in which liquid enflurane is delivered to the vaporizer by an infusion pump. Eight dogs were kept anesthetized with enflurane for 2 h using this device. Vital signs and arterial blood gases were within normal limits during anesthesia. The concentration of vaporized enflurane, measured by mass spectrometry, could be reliably and accurately controlled within the clinical range at any minute volume by adjusting the infusion rate. Measurements of blood enflurane indicated that enflurane uptake could be adequately achieved.