Abstract:

Objective To compare the sealing effects of direct and indirect pressure measurement methods on cuffs with taper and columnar shapes. Methods Cuffs were divided into the taper and columnar shapes,both groups were measured using direct and indirect measurement procedures,and the fluid leakage of two groups were observed. The direct measurement method monitored pressure by a directly linked handheld pressure gauge,while the indirect measurement method added a 3-way stopcock between the handheld pressure gauge and the cuff. We locked the 3-stopcock to stabilize handheld pressure gauge reading at 32 cmH₂O before measure the pressure. Results The pressure of the taper shaped cuffs in direct measurement group was（21.73±0.30） cmH₂O while the pressure of column shaped cuffs was（25.01±0.13） cmH₂O,which showed a statistically significant difference （P<0.01）. Fluid on the two types of cuffs all leaked after direct measurement. The pressure of the taper shaped cuffs in indirect measurement group was（31.08±0.31） cmH₂O,and（31.10±0.17） cmH₂O in columnar shape,without significant difference（P>0.05）. Fluid on the taper shaped cuffs didn’t leak after indirect measurement procedures yet the fluid on column shaped cuffs all leaked. Conclusion The direct measurement method can cause pressure decreasing in taper and column shaped cuffs as well as fluid leakage. Indirect measurement method can lose only 1~2 cmH₂O of pressure for taper and column shaped cuffs,and the taper shaped cuffs can seal fluid leak effectively.

Key words: Ventilators, Mechanical, Pneumonia, Ventilator-Associated, Direct Pressure Measurement, Indirect Pressure Measurement, Taper-Shaped Cuff, Column-Shaped Cuff

摘要：

目的 比较直接和间接两种测压法用于锥形和柱形套囊压力检测后密闭气道的效果。方法 分为锥形套囊组和柱形套囊组,两组均采用直接测压法和间接测压法进行压力检测,同时进行液体渗漏实验观察套囊的气道密闭效果。直接测压法采用测压表直接连接指示套囊进行压力检测;间接测压法在测压表上加1个三通管,锁定测压表压力为32 cmH₂O（1 cmH₂O=0.098 kPa）后再连接指示套囊检测。 结果 直接测压法检测锥形套囊组和柱形套囊组压力分别为（21.73±0.30） cmH₂O和（25.01±0.13） cmH₂O,两组比较,差异有显著统计学意义（P<0.01）;测压后1 min内两组套囊上液体均全部渗漏。间接测压法检测锥形套囊组和柱形套囊组压力分别为（31.08±0.31） cmH₂O和（31.10±0.17） cmH₂O,两组比较,差异无统计学意义（P >0.05）;测压后10 min内锥形套囊组套囊上液体无渗漏,柱形套囊组套囊上液体缓慢渗漏。结论 直接测压法可导致锥形和柱形套囊内压力明显下降及套囊上液体完全渗漏;间接测压法检测后锥形和柱形套囊的压力损失仅1~2 cmH₂O,锥形套囊可有效阻隔套囊上液体渗漏。

关键词: 通气机, 机械, 肺炎, 呼吸机相关性, 直接测压, 间接测压, 锥形套囊, 柱形套囊