改良自主呼吸诱发试验在脑死亡判定中的应用

The use of modified apnea test in the brain death evaluation

目的评价改良自主呼吸诱发试验（modified apnea test，MAT）在脑死亡判定中的安全性及可行性。方法采用前瞻性自身对照研究。监测43例脑死亡判定患者在改良自主呼吸诱发试验期间的呼吸运动、血液动力学及氧合，并对试验前后的心率（HR）、有刨动脉血压（ABP）、动脉血酸碱度（pH）、动脉血二氧化碳分压（PaCO2）、动脉血氧分压（PaO2）进行测定比较。计量资料以均数±标准差（x^-±s）表示，进行配对资料t检验。非正态分布采用配对符号等级秩次检验。所有试验均获得了患者亲属的同意，并履行了国内外相关法律法规所规定的程序。结果43例患者进行了85次改良自主呼吸诱发试验，试验期间血液动力学和氧合稳定，结果均为阳性。89．4％的试验在4min完成，10．6％在8min完成；试验期间PaCO2上升值的均数为（23．1±4．8），平均CO2上升速率为5．3mmHg／min。结论改良自主呼吸诱发试验可应用于脑死亡判定，作为自主呼吸诱发试验有益的补充。

Objective To evaluate the safety and feasibility of the modified apnea test （MAT） for brain death evaluation. Method A prospective, controlled clinical study was carried out. Forty-three patients with suspected brain death underwent a total of 85 MATs. The patient＇ s spontaneous breathing, hemedynamics and oxygenation were monitored during MAT; arterial blood pH, PaCO2, PaO2 were measured before and after the MAT. Paired t test was used for statistical analysis to determine significant differences in measurements before and after MAT on the same patient. The Wilcoxon Signed-Rank Test was used to determine statistical significance for skew distribution of PaO2 before and after apnea testing. Informed consent was obtained from the kinfolk of all participants and all of the procedures were done in accordance with national and international laws and policies. Results Hemodynamics and oxygenation were stable in all patients during MAT, and none regained spontaneous respiration. About 89.4% of tests were completed within 4 minutes, and 10.6% within 8 minutes. The mean value of PaCO2 rise was （23.1 ± 4.8）, and the average rate of PaCO2 increase was 5.3 mmHg per minute. Conclusions Modified apnea test can be done safely for brain death evaluation and is a useful suPPlement to the common aDnea test.