Moore D P, Weston A R, Hughes J M, Oakley C M, Cleland J G
Division of Clinical Cardiology, Royal Postgraduate Medical School, London, UK.
Lancet. 1992 Apr 4;339(8797):850-3. doi: 10.1016/0140-6736(92)90288-e.
Exercise capacity in patients with stable heart failure may be influenced by prolonged drug treatment or exercise training, but acute interventions are generally thought to have little effect. Cardiorespiratory responses to exercise were studied in 12 consecutive patients with chronic congestive heart failure who underwent serial submaximal and maximal exercise tests at inspired oxygen concentrations of 21% (room air), 30%, and 50%. Mean (SD) exercise duration during progressive testing to maximum exercise capacity was prolonged from 548 (276) s on room air to 632 (285) s on 50% oxygen (p = 0.012). During steady-state exercise at 45 W, oxygen enrichment to 50% was associated with significantly increased arterial oxygen saturation (94.6 [1.9]% to 97.5 [1.3]%), and significantly reduced minute ventilation (36.1 [8.6] l/min to 28.1 [5.9] l/min), cardiac output (7.5 [2.3] l/min to 6.5 [1.9] l/min), and subjective scores for fatigue and breathlessness (13.9 [3.1] to 11.5 [3.5]) compared with room air intermediate changes were observed with 30% inspired oxygen. Increased inspired oxygen concentrations can improve exercise performance acutely and modify the ventilatory response to exercise in patients with heart failure. Hyperoxia reduces ventilatory response and circulatory demand while maintaining oxygen delivery at a given workload. The potential benefits of increased inspired oxygen concentrations in the treatment of chronic heart failure merit further assessment.
稳定型心力衰竭患者的运动能力可能会受到长期药物治疗或运动训练的影响，但一般认为急性干预效果甚微。对12例慢性充血性心力衰竭患者进行了研究，这些患者在吸入氧浓度为21%（室内空气）、30%和50%的情况下，连续进行了次极量和极量运动试验，以观察其心肺对运动的反应。在递增测试至最大运动能力期间，平均（标准差）运动持续时间从在室内空气时的548（276）秒延长至在50%氧气时的632（285）秒（p = 0.012）。在45瓦的稳态运动期间，与室内空气相比，将氧气浓度提高到50%可使动脉血氧饱和度显著增加（从94.6[1.9]%增至97.5[1.3]%），分钟通气量显著降低（从36.1[8.6]升/分钟降至28.1[5.9]升/分钟），心输出量显著降低（从7.5[2.3]升/分钟降至6.5[1.9]升/分钟），疲劳和呼吸困难的主观评分显著降低（从13.9[3.1]降至11.5[3.5]）；吸入30%氧气时观察到有中间变化。提高吸入氧浓度可急性改善心力衰竭患者的运动表现，并改变其对运动的通气反应。高氧可降低通气反应和循环需求，同时在给定工作量下维持氧气输送。提高吸入氧浓度在治疗慢性心力衰竭中的潜在益处值得进一步评估。
