Ahmedzai S H, Laude E, Robertson A, Troy G, Vora V
Academic Palliative Medicine Unit, Clinical Sciences Division (South), Royal Hallamshire Hospital, Glossop Rd, Sheffield S10 2JF, UK.
Br J Cancer. 2004 Jan 26;90(2):366-71. doi: 10.1038/sj.bjc.6601527.
Helium has a low density and the potential of reducing the work of breathing and improving alveolar ventilation when replacing nitrogen in air. A Phase II, double-blind, randomised, prospective, controlled trial was undertaken to assess whether Heliox28 (72% He/28% O(2)) compared with oxygen-enriched air (72% N(2)/28% O(2)) or medical air (78.9% N(2)/21.1% O(2)) could reduce dyspnoea and improve the exercise capability of patients with primary lung cancer and dyspnoea on exertion (Borg >3). A total of 12 patients (seven male, five female patients, age 53-78) breathed the test gases in randomised order via a facemask and inspiratory demand valve at rest and while performing 6-min walk tests. Pulse oximetry (SaO(2)) was recorded continuously. Respiratory rate and dyspnoea ratings (Borg and VAS) were taken before and immediately post-walk. Breathing Heliox28 at rest significantly increased SaO(2) compared to oxygen-enriched air (96+/-2 cf. 94+/-2, P<0.01). When compared to medical air, breathing Heliox28 but not oxygen-enriched air gave a significant improvement in the exercise capability (P<0.0001), SaO(2) (P<0.05) and dyspnoea scores (VAS, P<0.05) of lung cancer patients.
氦气密度低，在替代空气中的氮气时，有降低呼吸功和改善肺泡通气的潜力。开展了一项II期双盲随机前瞻性对照试验，以评估与富氧空气（72% N₂/28% O₂）或医用空气（78.9% N₂/21.1% O₂）相比，氦氧混合气28（72% He/28% O₂）是否能减轻原发性肺癌且运动时出现呼吸困难（Borg评分>3）患者的呼吸困难并提高其运动能力。共有12例患者（7例男性，5例女性，年龄53 - 78岁）通过面罩和吸气按需阀，在静息状态及进行6分钟步行试验时，以随机顺序吸入测试气体。持续记录脉搏血氧饱和度（SaO₂）。在步行前及步行结束后立即测量呼吸频率和呼吸困难评分（Borg评分和视觉模拟评分）。与富氧空气相比，静息时吸入氦氧混合气28显著提高了SaO₂（96±2 对比 94±2，P<0.01）。与医用空气相比，肺癌患者吸入氦氧混合气28而非富氧空气时，运动能力（P<0.0001）、SaO₂（P<0.05）和呼吸困难评分（视觉模拟评分，P<0.05）均有显著改善。
