阻塞性睡眠呼吸暂停低通气综合征患者运动心肺功能变化

目的评估阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者的运动心肺功能变化以期发现心血管疾病的潜在危险。方法30例OSAHS患者均应用多导睡眠监测仪(PSG)进行监测,根据呼吸紊乱指数(AHI)分为轻中度组和重度组。静态肺功能检查:测定用力肺活量(FVC)、第1秒用力呼气容积(FEV1)、FEV50及FEV25。运动心肺功能测定:行症状限制亚极量渐增运动负荷试验,基础负荷5 W,每分钟递增10 W;保持速度在40~50 r/min之间,以受试者感到极度呼吸困难或极度下肢疲劳或运动时SaO2低于85%时结束运动。运动中监测心电图、血压、SpO2、氧耗量(V.O2)、每分钟通气量(VE)及无氧阈(AT)测定等。20例单纯打鼾者作为对照组,均接受与OSAHS患者同样静态及运动心肺功能的测定。结果OSAHS组患者FVC、FEV1、FVC%pred、FEV1%pred、FEF25、FEF50与单纯打鼾组比较有显著性差异(P<0.05)。OSAHS组与单纯打鼾组运动心肺功能指标比较:(1)OS-AHS组在最大氧耗量、最大运动负荷(Wmax)、无氧阈(AT)及心率均低于单纯打鼾组(P<0.05)。(2)OSAHS患者的最大氧脉搏、Wmax及无氧阈与呼吸紊乱指数呈负相关(r分别为-0.610 3、-0.530 1和-0.485 3,P均<0.01),与夜间最低血氧饱和度呈正相关(r分别为0.5218、0.691 2及0.638 6,P均<0.05),与心率呈正相关(r分别为0.584 4、0.601 3及0.413 2,P均<0.05)。结论OSAHS患者心肺功能下降与长期反复发生的夜间低氧血症有关。轻度OSAHS即有心脏功能下降。低氧的时间越长,氧饱和度越低,心肺功能受损越严重。

Changes of exercise cardiopulmonary function in patients with obstructive sleep apnea-hypopnea syndrome

Objective To evaluate the changes of exercise cardiopulmonary function in patients with obstructive sleep apnea-hypopnea syndrome(OSAHS).Methods 30 cases with OSAHS and 20 cases with simple snoring were monitored overnight with polysomnography,and then OSAHS group were classified into mild to moderate and severe subgroups according to apnea-hyponea index(AHI).Static lung function tests were performed to measure forced vital capacity(FVC),forced expired volume in one second(FEV_1),as well as FEV_(50) and FEV_(25).Exercise cardiopulmonary function tests were conducted and parameters including SpO_2,blood pressure,oxygen consumption(_O_2),minute ventilation volume(V_E),anaerobic threshold(AT) were recorded.(Results) There were significant differences in FVC,FEV_1,FVC in percentage of predicted value(FVC% pred),FEV_1%pred,FEF_(25),and FEF_(50) between OSAHS group and simple snoring group(P<0.05).There were significant differences in_O_2 max,Wmax and AT between OSAHS group and simple snoring group(P<0.05).In the OSAHS group,_O_2 max,Wmax and AT were negatively related to AHI(r=-0.610 3,(-0.530 1),and-0.485 3,respectively,all P<0.01),and positively related to minimal SaO_2 in the night(r=0.521 8,0.691 2,and 0.638 6,respectively,all P<0.05).(Conclusion) Cardiopulmonary dysfunction in patients with OSAHS is concerned with nighttime hypoxemia which may occur even at early stage of the(disease).