[Tube change in nasotracheally intubated intensive care patients using injector ventilation: a method for the prevention of hypoxic complications].

Conventional methods for the replacement of nasotracheal tubes are often dangerous. The interruption of respiration while replacing the nasotracheal airway may cause severe hypoxia. We developed a technique which shortens the time of apnoe to a few seconds. A 16F nasogastric tube is connected to a simple jet ventilation device driven by 100% oxygen. The nasotracheal tube is disconnected from the respirator and its cuff deflated. While performing jet ventilation (inspiration time 1.5 sec, frequency 12/min., pressure 1.5-2 bar) the nasogastric tube is threaded into the nasotracheal tube until the tip lies inside its distal end. The old endotracheal tube can now be retracted over the nasogastric tube under continuous jet ventilation. The nasogastric tube need only be disconnected from the jet ventilator for a few seconds while the old endotracheal tube is replaced for a new one. Now the new endotracheal tube is guided into the trachea by the nasogastic tube while jet ventilation is continued. We used this technique 19 times without any complications. We found the method safe and simple, giving sufficient ventilation in all patients, provided that contraindications and precautions are observed.