慢性阻塞性肺疾病前驱性呼吸衰竭患者呼吸驱动的改变

目的探讨慢性阻塞性肺疾病(COPD)和COPD前驱性呼吸衰竭(前驱呼衰)患者中枢呼吸驱动的改变;评价界定COPD前驱性呼吸衰竭的临床意义.方法试验对象为COPD前驱性呼吸衰竭、COPD尚未达前驱性呼吸衰竭的患者和健康对照者各30名.所有受试者均进行如下参数的测定:动脉血气分析;常规肺功能,主要以第1秒用力呼气容积(FEV1)占预计值的百分比(FEV1%)来评价;中枢呼吸驱动水平,以0.1 s口腔阻断压(P0.1)、校正中枢呼吸驱动(以每分通气量来校正,即P0.1/MV)和吸气阻抗P0.1/VT/Ti)等来评价.结果P0.1和P0.1/MV在COPD前驱呼衰组明显高于正常对照组和未达前驱呼衰组,P0.1/VT/Ti在COPD前驱呼衰组和未达前驱呼衰组明显高于正常对照组(P=0.002);P0.1,P0.1/MV,P0.1/VT/Ti与PaO2,FEV1%呈显著负相关(rs=-0.769,-0.495,-0.543;-0.747,-0.480,-0.526,P均＜0.01);与PaCO2呈显著正相关(rs=0.270,0.312,0.369,P分别为＜0.05,＜0.01,＜0.01).结论COPD前驱呼衰患者呼吸储备能力减低,呼吸效率下降;P0.1,P0.1/MV,P0.1/VT/Ti等参数在推断患者神经-肌力输出水平与呼吸衰竭发生阈值方面具有较大的意义.当COPD进展至前驱呼衰阶段,从血气分析、肺功能检查到呼吸驱动水平都发生了显著的改变,从而提示界定此阶段具有一定的临床意义.

Changes of respiratory drive in pre-respiratory failure patients with chronic obstructive pulmonary disease

Objective: To clarify the changes of respiratory drive in pre-respiratory failure patients with chronic obstructive pulmonary disease (COPD), the profiles of control of breathing were investigated. To evaluate the clinical significance of making the stage of pre-respiratory failure in COPD. Methods: About 30 normal control volunteers, 30 patients with COPD and 30 pre-respiratory failure patients with COPD were enrolled in our trial. The pulmonary functions, analysis of arterial blood gas, respiratory drive-the mouth occlusion pressure at 0.1 s after onset (P0.1), corrected P0.1 (P0.1/MV) and inspiratory impedance (P0.1/VT/Ti) were measured in the three groups. Results: P0.1 and P0.1/MV were significantly increased in the COPD pre-respiratory failure group compared with that in other two groups. In both COPD groups, P0.1/VT/Ti was significantly higher than that in the control group (P =0.002). Otherwise, P0.1, P0.1/MV and P0.1/VT/Ti were significantly negatively related to PaO2 and FEV1%(rS=-0.769, -0.495, -0.543; -0.747, -0.480, -0.526, P <0.01), whereas positively correlated with PaO2 (rS=0.270, 0.312, 0.369 P <0.05, 0.01, 0.01). Conclusions: Measurement of P0.1, P0.1/MV and P0.1/VT/Ti in our research reveals increased of neuromuscular drive, inspiratory impedance, and decreased of respiratory efficiency, respiratory storage capacity in COPD pre-respiratory failure subjects. In pre-respiratory failure patients with COPD, respiratory drive parameters P0.1, P0.1/MV and P0.1/VT/Ti are significantly increased compared with those in control group and COPD group. That is to say when COPD progresses into the stage of pre-respiratory failure, many aspects from analysis of arterial blood gas, pulmonary functions to respiratory drive, have taken place significant changes, which in turn, demonstrated that the COPD pre-respiratory failure stage is indeed a critical one. Monitoring the changes of all above parameters will help us to evaluate the degree of COPD and to take measures to cure the disease.