Clinical use of high frequency ventilation.

High-frequency jet ventilation (HFJV) and high-frequency positive pressure ventilation (HFPPV) occupy a specific place in the wide range of ventilatory support techniques available for anesthesia and critical care. In anesthesia, HFJV and HFPPV have been proved to be superior to conventional ventilation in ENT surgery, laryngoscopies, laser surgery, bronchoscopies, surgery of the upper airways, surgical resection of aneurysms involving the thoracic descending aorta, vocal cord surgery, microsurgery for superficial temporal artery to middle cerebral artery anastomosis and lithotripsy. In intensive care, HFJV and HFPPV offer some advantages over conventional ventilation with PEEP in the presence of acute respiratory failure with circulatory shock, acute ventricular failure, bronchopleural fistula with large airleak flows and tracheal lesions secondary to tracheostomy or prolonged intubation. In many other clinical situations HFJV and HFPPV have produced results identical with those obtained with conventional ventilation. Chronic obstructive pulmonary disease and asthma are absolute contra-indications to both techniques because overdistension and/or hypoventilation occur in the presence of increased respiratory compliance and/or elevated bronchial resistance. In unilateral lung disease HFJV and HFPPV offer no advantage over conventional ventilation.