The effects of inspiratory to expiratory ratio on ventilation and oxygenation during high frequency partial liquid ventilation in a rabbit model of acute lung injury / 대한마취과학회지

ABSTRACT

BACKGROUND: We examined the effects of varying inspiratory to expiratory (I E) ratio on gas exchange and hemodynamics during high frequency partial liquid ventilation (HFPLV), a combination of high frequency ventilation (HFV) and partial liquid ventilation (PLV), in a rabbit model of acute lung injury. METHODS: Twelve rabbits treated with repeated saline lavage were divided into two groups. In the HFPL group (n = 6), 6 ml/kg of perfluorodecaline was administered through the endotracheal tube. Rabbits in this group and in the HFJ group (n = 6) were treated with high frequency jet ventilation (HFJV) at I E ratios of 1 1, 1 2, and 1 3 for 15 minutes, and arterial blood gas, mixed venous blood gas and hemodynamic parameters were measured. RESULTS: We observed no significant respiratory and hemodynamic differences between the two groups. At an I E ratio of 1 1, the PaO2 was significantly higher, and the shunt rate and PaCO2 were significantly lower in both groups, compared with I E ratios of 1 2 and 1 3. Cardiac output at the 1 3 I E ratio was significantly higher than at 1 1. CONCLUSIONS: These findings indicate that, in this model, a 1 1 I E ratio was superior for oxygenation and ventilation than I E ratios of 1 2 or 1 3, while having no detrimental effects on hemodynamics.