双水平压力调节通气与反比通气对健康及急性肺损伤犬心肺功能影响的比较研究

目的 :比较双水平压力调节 (BIPAP)通气和反比通气 (IRV)对心肺功能的影响。方法 :在两种通气模式 0、0 .5和 1.0 k Pa呼气末压 (EEP)时 ,分别测定健康犬及油酸诱发急性肺损伤犬的呼吸力学、血流动力学及血气分析各参数。结果 :无论有无急性肺损伤 ,BIPAP通气时平均气道压 (m Paw )均明显低于 IRV时(P均 <0 .0 5 )。给健康犬用 IRV通气时 ,上述 3种 EEP水平的 m Paw分别为 (0 .437± 0 .10 3) k Pa、(0 .811±0 .0 93) k Pa和 (1.36 0± 0 .119) k Pa;用 BIPAP通气时则分别降为 (0 .2 2 5± 0 .0 71) k Pa、(0 .6 11± 0 .10 5 ) k Pa和(1.10 7± 0 .0 89) k Pa。油酸诱发急性肺损伤后 ,m Paw分别由 IRV时 (0 .72 5± 0 .2 2 2 ) k Pa、(1.186± 0 .2 98) k Pa和 (1.6 0 0± 0 .10 0 ) k Pa降至 BIPAP时 (0 .35 0± 0 .12 9) k Pa、(0 .6 2 5± 0 .15 0 ) k Pa和 (1.12 5± 0 .0 96 ) k Pa;但两种通气模式中气道峰压、心排血量并无明显差异。另外 ,急性肺损伤时 ,BIPAP通气的动脉血氧分压 (Pa O2 )分别为 (9.10± 1.79) k Pa、(11.43± 1.80 ) k Pa和 (13.40± 3.2 0 ) k Pa,较 IRV时 Pa O2 (7.87± 2 .33) k Pa、(9.0 7±3.0 5 ) k Pa和 (9.71± 1.85 ) k Pa增高 (EEP 1.0 k Pa时 ,P <0 .0 5 )。结论 :

Cardiopulmonary effects of two modes of mechanical ventilation in dogs with and without acute lung injury:comparison of pressure regulated biphasic positive airway pressure ventilation and inverse ratio ventilation

Objective:To compare the cardiopulmonary effect of pressure regulated biphasic positive airway pressure (BIPAP) and inverse ratio ventilation (IRV) on cardiac and pulmonary function.Methods:Airway pressure,hemodynamics and blood gases were measured during the two ventilatory modalities with 0,0 5, 1 0 kPa external endexpiratory pressure (EEP) in dogs with and without oleic acidinduced lung injury.Results:Airway pressure during BIPAP was lower than that with IRV with or without acute lung injury(all P <0 05 ).However,there was no difference in cardiac output.In dogs with lung injury,PaO 2 during BIPAP was higher than that during IRV.Conclusions:Compared with IRV,BIPAP can reduce the airway pressure,and improve PaO 2 in dogs with lung injury,although the cardiac output was not increased.