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In six suffocating patients with a severe upper airway obstruction (three patients after direct laryngoscopy under general anaesthesia and three patients with cervical tumor scheduled for a difficult tracheostomy), jet-ventilation was delivered using a transtracheal catheter. The jet-ventilator insufflated oxygen only when the tracheal pressure was below a preset value, during spontaneous inspiration. During expiration, tracheal pressure increased above the preset value, the ventilator stopped the insufflation and the expiratory gases escaped through the upper airway. This method corresponds to an inspiratory support without intubation. In post-anaesthesia patients, oxygenation and alveolar ventilation were improved, allowing the avoidance of tracheostomy. In the other patients, tracheostomy was made possible with good surgical conditions under general anaesthesia. This method can be applied in conscious patients and allows oxygenation of suffocating patients.

For the last 40 years transtracheal ventilation has been suggested as a means of bypassing the glottis in emergency in patients unable to be intubated or ventilated by mask. A catheter has been designed to be easily inserted into the crico-thyroid membrane. The outer part of the device, with its dual attachment system, can be connected to conventional resuscitation equipment by its 15 mm male end or to a high-pressure oxygen source by its Luer-Lock fitting. The advantages of transtracheal ventilation are: a clear vision of the operative field, a good gas exchange, an elimination of airway trauma from intubation, a reduction of the hazard of airway fires and a decreased risk of aspiration of blood and debris. Barotrauma is the main danger. However, this method of providing oxygen and/or mechanical ventilation may be extended to the postoperative period, the exit of the insufflated gas mixture being assured at all times.

The authors describe the methodology of high frequency ventilation in the newborn infant. Ventilation by oscillator (HFO) actually represents the best method for ventilation in newborn infants; the rate of ventilation is between 15 and 25 Hz/min. They report their experience of HFO use for the treatment of hyaline membrane disease in newborns.