Parameters of high-frequency jet ventilation using a mechanical lung model.

High frequency jet ventilationis a mechanical lung ventilation method which uses a relatively high flow usually through an open system. This work examined the effect of high-frequency jet ventilation on respiratory parameters of an intubated patient simulated using a high-frequency jet ventilator attached to a ventilation monitor for measurements of ventilation parameters. The series of experiments altered specific parameters each time (respiratory rate, inspiratory-expiratory (I:E) ratio, and inspiratory pressure), under different lung compliances.

Percutaneous Dilatational Tracheostomy Using Tube Exchanger.

We describe a modified technique for percutaneous dilatational tracheostomy using a 15F tube exchanger or Eschmann catheter. A retrospective review of 1180 procedures using this modified technique demonstrated it to be effective with a failure rate of only 0.25% (3 patients).

Power spectral analysis of heart rate variability during helium pneumoperitoneum: The mechanism of increased cardiac sympathetic activity and its clinical significance.

Background: Carbon dioxide pneumoperitoneum (PP) is known to induce increased cardiac sympathetic expression. The role of the insufflated gas involved in this mechanism should be elucidated in an attempt to eliminate its possible serious consequences.

Methods: Twenty-five patients undergoing elective laparoscopic cholecystectomy were prospectively analyzed for cardiac autonomic nervous activity by spectral heart rate variability.