不同腹腔压对神经调节辅助通气中膈肌电活动和潮气量的影响

Influence of different intra-abdominal pressure on the electrical activity of the diaphragm and tidal volume for neurally adjusted ventilatory assist

目的:探究神经调节辅助通气(NAVA)中的膈肌电活动(EAdi)及潮气量于不同腹腔压(IAP)时的变化情况,为临床通气参数设置提供参考。方法:选取2015年1月至10月在衢州市人民医院ICU病房机械通气患者44例,入选标准为年龄>18岁,呼吸末正压(PEEP)通气在3~5 cmH_2O(1 cmH_2O=0.098 kPa)并且预测通气时间≥72 h的患者。通过膀胱注入0.9%氯化钠溶液的方法间接测量出IAP,每次间隔6 h,依据国际腹腔间隙综合征学会(WSACS)对高IAP的定义将12 mmHg(1 mmHg=0.133 kPa)设定为分界线,区分高腹内压和非高腹内压。经鼻放置EAdi导管于每小时测定EAdi值,同时记录潮气量。结果:高腹内压组EAdi值[(5.8±0.7)μV]显著低于非高腹内压组[(6.8±0.6)μV],差异有统计学意义(P<0.05),高腹内压组潮气量[(9.6±1.3)mL/kg]显著高于非高腹内压组[(8.8±1.0)mL/kg],差异有统计学意义(P<0.05)。结论:NAVA中,高IAP时,EAdi数值降低,潮气量增多;非高IAP时,EAdi数值升高,潮气量减少。

Objective: To evaluate how IAP affects the EAdi and the tidal volume (VT) during NAVA was meaningful to set parameters of clinical ventilation. Methods: Forty-four patients in ICU were enrolled in this study. Inclusion criteria: over 18 years old adult who was going to use mechanical ventilation for over 72 hours at positive end-expiratory pressure (PEEP) 3-5 cmH2O (1 cmH2O=0.098 kPa). IAP was indirectly measured by injecting saline to bladder with 6 hours interval. The dividing line of high IAP and non-high IAP was set as 12 mmHg (1 mmHg=0.133 kPa) according to WSACS. By a EAdi catheter via nose EAdi was recorded with VT hourly. Results: EAdi was significant lower when IAP was over than 12 mmHg; and VT was significant higher when IAP was less than 12 mmHg. Conclusion: The changes of EAdi and VT under different IAP during NAVA:when IAP was high, EAdi decreases while VT increases and vice-versa.