无创正压通气时不同吸气努力对呼吸力学参数测算的影响  

The influence on accuracy of respiratory mechanics estimation with different inspiratory effort during noninvasive ventilation:a bench study

作　　者：陈宇清 袁越阳 张海[1] 李锋 李兴旺[3] CHEN Yuqing;YUAN Yueyang;ZHANG Hai;LI Feng;LI Xingwang(Department of Respiratory and Critical Care Medicine,Shanghai Chest Hospital,Shanghai Jiao Tong University,Shanghai 200030,P.R.China;School of Mechanical and Electrical Engineering,Hunan City University,Yiyang,Hunan 413049,P.R.China;The Bio-X Institutes,Shanghai Jiao Tong University,Shanghai 200030,P.R.China)

机构地区：[1]上海交通大学附属胸科医院呼吸与危重症医学科,上海200030 [2]湖南城市学院机械与电气工程学院,湖南益阳413049 [3]上海交通大学Bio-X研究院,上海200030

出　　处：《中国呼吸与危重监护杂志》2021年第10期715-720,共6页Chinese Journal of Respiratory and Critical Care Medicine

基　　金：上海交通大学“交大之星”医工交叉研究基金(G2019ZDB08)。

摘　　要：目的应用动态信号分析法评估无创正压通气(NPPV)时不同吸气努力对肺力学模型呼吸力学参数测算的影响。方法选择ASL5000机械模拟肺模拟体重为65~70 kg的半卧位健康成年人、慢性阻塞性肺疾病和急性呼吸窘迫综合征患者。吸气压力(P_(mus))分别为0、5.0、10.0和15.0 cm H_(2)O。Respironics V60呼吸机以自主/时间控制模式运行,呼气末正压为5.0 cm H_(2)O,调整P_(mus)使呼吸机输出潮气量为7.0 mL/kg,后备通气频率为10次/min。收集系统泄漏量为25~28 L/min时的通气参数变化并计算呼吸力学参数系统顺应性(C_(rs))和气道阻力(Raw)。结果随着P_(mus)增大,三种肺力学模型的驱动压(DP)逐渐减小;P_(mus)超过10.0 cm H_(2)O后健康成年人模型的呼出潮气量显著超过7.0 mL/kg,DP降至1.0 cm H_(2)O。高水平P_(mus)时C_(rs)呈过高测算,而Raw测算值显著降低。低水平P_(mus)时慢性阻塞性肺疾病和急性呼吸窘迫综合征模型的呼气阻力(R_(exp))和C_(rs)测算误差≤10%,不同P_(mus)水平时吸气阻力(Rinsp)测算值均显著低于预设值(P<0.01)。结论通过应用动态信号分析法,可实现NPPV时在不阻断自主呼吸条件下连续监测C_(rs)和Raw(尤其是R_(exp)),过强的P_(mus)会导致呼吸力学测算误差增大。Objective To evaluate the influence on the estimation of respiratory mechanics with dynamic signal analysis approach during noninvasive positive pressure ventilation(NPPV)under different inspiratory effort conditions.Methods The Respironics V60 ventilator was connected to a ASL5000 lung simulator,which simulate lung mechanics in healthy adults with body weight from 65 to 70 kg,and patients with chronic obstructive pulmonary disease(COPD)and acute respiratory distress(ARDS).Each lung models was subjected to 4 different muscle pressures(P_(mus)):0,5.0,10.0,and 15.0 cm H_(2)O.Inspiratory pressure support level was adjusted to maintain tidal volume(VT)achieving 7.0 mL/kg outputted by ventilator respectively.Positive end expiratory pressure was set at 5.0 cm H_(2)O and back-up rate was 10 beats per minute.Measurements were conducted at system leaks with 25 to 28 L/min.The respiratory system compliance(C_(rs)),inspiratory and expiratory resistance(Rinsp and R_(exp))were estimated by special equations,which was derived from the exhaled VT,flow rate and airway pressure.Results The driving pressure(DP)was decreased with P_(mus) increasing,and was 1.0 cm H_(2)O after P_(mus) exceeding 10.0 cm H_(2)O and the VT was larger than 7.0 mL/kg in normal adult model.The estimated value of C_(rs) was affected by the changes of P_(mus) in all three lung models.The significant underestimation of Raw and the overestimation of C_(rs) were observed when P_(mus) level exceed 10.0 cm H_(2)O.The measured errors of C_(rs) and R_(exp) were within 10%in COPD and ARDS model when P_(mus) was at 5.0 cm H_(2)O.The underestimation of Rinsp was always existed in all P_(mus) level(P<0.01).Conclusions Using dynamic signal analysis approach,the real-time estimation of respiratory mechanics(C_(rs) and Raw)is no need to interrupt the spontaneous breathing during NPPV.Excessive effort will increase the patient’s inspiratory workload,which is not benefit to accurate estimation of respiratory mechanics.

关 键 词：呼吸力学 阻力 顺应性 动态 无创通气 

分 类 号：R563.9[医药卫生—呼吸系统]