功能性呼吸困难患者呼吸中枢负反馈机制的评价

Evaluation on negative feedback mechanism of respiratory center in patients with functional dyspnea

目的探讨功能性呼吸困难患者呼吸中枢负反馈机制特点。方法临床诊断功能性呼吸困难12例，设立器质性疾病组和正常对照组各12例，分别检测各组过度通气试验前后屏气时间，数据行单因素方差分析。结果功能性呼吸困难组过度通气试验前、后屏气时间分别为：（62．67±20．4）s与（42．08±22．20）s，过度通气后屏气时间较过度通气前屏气时间缩短。器质性疾病组、正常对照组则过度通气后屏气时间较过度通气前屏气时间延长。功能性呼吸困难组与器质性疾病组、正常对照组相比存在显著差异，P〈0．001。结论器质性疾病组及正常对照组过度通气试验后屏气时间延长，符合呼吸中枢负反馈机制，功能性呼吸困难组过度通气试验后屏气时间较过度通气前缩短，不符合呼吸中枢负反馈机制，考虑患者组呼吸中枢负反馈机制减弱或缺失。

Objective To investigate the characteristics of negative feedback of respiratory center in patients with functional dyspnea. Methods Thirty-six subjects were divided into functional dyspnea group （ n = 12）,organic disease group （ n = 12） and normal control group （ n =12）. Breath holding time （BHT） before and after hyperventilation test was compared among groups. Parameters were analysed with one-factor analysis of variance. Results BHT in functional dyspnea group was （62.67±20.4 ） seconds before hyperventilation and （42.08±22.20） seconds after hyperventilation. BHT was significantly shorter after hypervention than before hyperventilation in this group. However. BHT was longer after hyperventilation than before hyperventilation in both organic disease group and normal control group. Functional dyspnea group showed a significant difference in BHT from organic disease and normal control group（ P〈0. 001）. Conclusions The longer BHT after hyperventilation in organic disease and normal control groups can be explained by the negative feedback mechanisms of respiratory center. But the shorter BHT after hyperventilation in functional dyspnea group is not in accordance with the feedback mechanisms of respiratory center and we consider that there may be weakening or loss of feedback mechanism in this group.