抽象的
该研究比较了常规受试者和慢性阻塞性肺疾病(COPD)患者外部负压通气(ENPV)的急性生理效应。该设备由气密夹克(气胸)和真空泵组成。使用发光涡轮机换能器记录微小通风(VE)。每30秒计算氧吸收(VO2)和二氧化碳输出(VCO2)。测量在静止和eNPV期间,具有-20cmH2O和-40cmH2O的压力。呼吸机速率在16.Min-1固定。在10个正常受试者中,VE从8.6增加到22.9 L.Min-1(P小于0.01),伴随着0.25至0.39L.min-1的VCO2增加(p小于0.01)。在10名NormoCapnic COPD患者(平均二氧化碳张力(PACO2)小于6.0 KPA),在10例高碳化患者(PACO2大于6.0 KPA)ve中增加了11.5至17.1μlmin-1(p小于0.01)9.7至12.4 L.Min-1(p小于0.01)。在COPD患者中未检测到VCO2的变化,VO2在任何组中没有变化。 Arterial blood samples were obtained in eight hypercapnic patients. Baseline mean physiological deadspace ventilation (VD) was calculated to be 4.9 l.min-1 (56% of Ve) whilst Ve was 8.8 l.min-1 in this subgroup. During ENPV, arterial oxygen tension (PaO2) increased from 6.8 to 8.2 kPa (p less than 0.01) whilst PaCO2 decreased from 6.8 to 5.8 kPa (p less than 0.01) suggesting that despite the large physiological deadspace, a significant increase in alveolar ventilation had occurred. In advanced COPD, thoracic compliance falls and limits the ventilatory response to ENPV.(ABSTRACT TRUNCATED AT 250 WORDS)