Approach to treatment of acute respiratory failure with liquid ventilation

Liquid ventilation using Perflubron has been investigated for more than 30 years. Many investigators demonstrated beneficial effects of liquid ventilation in the setting of respiratory failure in animals. It is thought that liquid ventilation could be a new treatment for acute respiratory distress syndrome (ARDS). There are two methods in liquid ventilation. One is total liquid ventilation (TLV), in which the lungs are filled with Perflubron. The other one is, so to speak, partial liquid ventilation (PLV), in which the lungs are partially filled with Perflubron. Nowadays, partial liquid ventilation is applied in many animal studies and clinical trials, although total liquid ventilation is applied only in animal studies. Liquid ventilation using Perflubron has beneficial effects on gas exchange and a lung lavage effect in ARDS. In the rabbit model of respiratory failure induced by lung lavage, PLV produced significant improvement in blood gas compared with gas ventilation (GV) (PaO₂ 50±8 mmHg in GV, 225±91 mmHg in PLV; PaCO₂ 68±7 mmHg in GV, 44±5 mmHg in PLV). PLV also caused a decrease in myeloperoxidase (MPO) activity in a lung transplantation study in dogs (0.77±0.5 in GV, 0.38±0.25 in PLV). It is suggested that liquid ventilation might have an anti-inflammatory and lung protective effect. It is likely that liquid ventilation is a reasonable alternative. However, details of liquid ventilation, such as indications, management technique, and interaction with current therapy, are still unclear.