高频双向喷射通气对麻醉犬气体交换及血流动力学的影响

Effects of high frequency two-way jet ventilation on gas exchange and hemodynamics in anesthetized dogs

作者观察了高频双向喷射通气(HFTJV)时反喷驱动压和通气频率对麻醉犬气体交换及血流动力学的影响.结果表明:(在通气频率(100次/min)、正喷驱动压及吸/呼比均保持恒定的条件下,可见HFTJV时的Paco_2较HFJV时均显著降低(P<0.01),pH均显著升高(P<O.01),而Pao_2、平均气道压及血流动力学参数则均无明显改变。随着反喷驱动压从2.06,4.31增加到6.57kPa/kg,上述指标均无明显改变。②在反喷驱动压(4.31kPa/kg)、正喷驱动压及吸/呼比均保持恒定的条件下,可见HFTJV时的Paco_2较HFJV时均显著降低(P<0.05),pH均显著升高(P<0.01),而Pao_2、平均气道压及血流动力学参数则均无明显改变;无论在HFJV或HFTJV时,随着通气频率从60,100增加到200次/min,Paco_2均随之升高。结果提示,HFTJV具有促进CO_2排除的作用,HFTJV时的CO_2排除受通气频率的影响,反喷驱动压和通气频率的增加对麻醉犬的血流动力学无明显影响。

The effects of inverse driving pressure (IDP)and ventilatory frequency (f) on gas exchange and hemody-namics were studied in anesthetized dogs during high frequency two-way jet ventilation (HFTJV). The results showed that: (1)when f was 100 breaths/min, driving pressure (DP) and I/E ratio keep constant, Paco_2 was significantly lower and pH significantly higher in HFTJV than that in high frequency jet ventilation (HFJV), there were no significant changes in Pao_2, mean airway pressure and hemodynamic parameters; and neither in above variables when increasing IDP from 2.06, 431 to 6.57 kPa/kg; (2)when IDP (431 kPa/kg), DP and I/E ratio keep constant, Paco_2 was significantly lower and pH significantly higher in HFTJV than that in HFJV, there were no significant changes in Pao_2, mean airway pressure and hemodynamic parameters. Increasing f from 60, 100 to 200 breaths /min, Paco_2 correspondingly increased in HFJV or HFTJV. It is suggested that HFTJV can improve CO_2 elimination, and CO_2 elimination is influenced by ventilatory frequency during HFTJV. Increasing IDP and f had no influence on hemodynamic parameters.