重症患者呼气末读取中心静脉压与监护仪直接示数的比较分析

Compare the two methods of central venous pressure measurement by automatic reading and end-expiratory manual reading in critical patients

目的 :比较教科书所推荐的人工读取患者呼气末中心静脉压(Central Venous Pressure,CVP)数值和临床常采用直接读取监护仪CVP示数之间的相关性及差异,分析两种方法是否可以完全互相替代。方法 :纳入200例行CVP监测的重症患者,测量中心静脉压时同时采用呼气末人工读取CVP数值和监护仪直接示数两种方法进行读数,比较两种方法的差异。结果:(1)呼气末人工读取CVP与监护仪CVP示数呈高度正相关(r=0.905,P<0.001),但两种不同方法读取CVP数值偏差≥2 mm Hg(1 mm Hg=0.133 k Pa)的患者占17.0%;(2)在123例机械通气患者中,两种读取方法的相关系数r=0.915,但在77例自主呼吸患者中两种读取方法的相关系数r=0.886,机械通气患者和自主呼吸患者中两种方法读取数值偏差≥2 mm Hg分别占9.8%、28.6%;(3)在177例窦性心律的患者中,两种读取方法的相关系数r=0.921,但在23例心律失常患者中两种读取方法的相关系数r=0.891,窦性心律和心律失常患者中两种方法读取数值偏差≥2 mm Hg分别占15.3%、30.4%。结论 :在机械通气及窦性心律的患者中两种CVP读取方法相关性好,可相互替代;但是在自主呼吸和心律失常的患者中,两种CVP读取方法偏差较大,应用监护仪直接读取CVP须慎重,建议医务人员结合心电图波形在患者呼气末读取CVP数值。

Objective： To investigate the difference and relevance between central venous pressure （CVP） measurement by automatic reading and end-expiratory manual reading and to analyze as well as discuss if they could be substituted by each other Methods： A prospective observational study included 200 critically ill patients who received CVP monitoring and received CVP measurements by automatic reading of monitor system and manual reading at the end of expiration was applied. We compared the difference between these two methods. Results：（1）CVP measurement by automatic reading was significantly positively correlated with the results obtained by end-expiratory manual reading （r=0.905, P〈0.001）, and patients with difference between two measurements greater than 2 mmHg accounted for 17.0%. （2） Of the 123 mechanical ventilated patients, the correlation between two measurements was r=0.915, while of the 77 spontaneous breathing patients, the correlation was r=0.886. The patients with difference between two measurements greater than 2 mmHg accounted for 28.6%,4 （spontaneous breathing） and 9.8% （mechanical ventilation）. （3） Of the 177 patients who had sinus rhythm, the correlation between the two measurements was r=0.921, while the correlation was r=0.891 of the 23 arrhythmic patients, patients with difference between two measurements greater than 2 mmHg accounted for 30.4% （arrhythmia） and 15.3% （sinus rhythm）. Conclusion： The two measurements correlated well in fully mechanical ventilated patients and the results showed that they could be replaced by each other. But the difference between two methods was greater in spontaneous breathing patients and arrhythmic patients, so we should be alerted when results of automatic reading were applied.