Cardiothoracic and Vascular Department, Respiratory and Critical Care Unit, Careggi University Hospital, Largo Brambilla 3, 50134 Florence, Italy.
Pneumologic Centre 'Misericordia', Sesto Fiorentino, Florence, Italy.
Br J Anaesth. 2018 Jan;120(1):18-27. doi: 10.1016/j.bja.2017.11.010. Epub 2017 Nov 21.
Oxygen therapy is first-line treatment for hypoxaemic acute respiratory failure (ARF). High-flow nasal oxygen therapy (HFNO) represents an alternative to conventional oxygen therapy. HFNO provides humidified, titrated oxygen therapy matching or even exceeding the patients' inspiratory demand. The application of HFNO is becoming widespread in Intensive Care Units (ICUs), favoured by increasing evidence based on numerous studies supporting its efficacy. The mechanisms of action and physiological effects of HFNO are not yet fully understood. Pharyngeal dead space washout, decrease in airway resistance, generation of a positive end-expiratory pressure, and enhanced delivery of oxygen are all alleged to be potential mechanisms. The emerging evidence suggests that HFNO is effective in improving oxygenation in most patients with hypoxaemic ARF of different aetiologies. Notwithstanding the potential benefit of HFNO in the management of hypoxaemia, further large cohort studies are necessary to clarify the indications, contraindications and factors associated with HFNO failure. HFNO may also be valuable in reducing the need for tracheal intubation in the management of post-extubation ARF. In addition, HFNO has been proposed to limit oxygen desaturation by prolonging apnoeic oxygenation during intubation both in ICUs and operating theatres.
氧疗是治疗低氧性急性呼吸衰竭（ARF）的一线治疗方法。高流量鼻氧疗法（HFNO）是传统氧疗的替代方法。HFNO 提供加湿、滴定氧疗，可满足甚至超过患者的吸气需求。HFNO 在重症监护病房（ICU）中的应用越来越广泛，越来越多的研究支持其疗效，这为其提供了更多的证据。HFNO 的作用机制和生理效应尚不完全清楚。据称，咽腔死腔冲洗、气道阻力降低、呼气末正压产生以及氧输送增加都是潜在的机制。新出现的证据表明，HFNO 可有效改善不同病因所致低氧性 ARF 患者的氧合。尽管 HFNO 在低氧血症管理中有潜在益处，但仍需要进行更多的大型队列研究来阐明 HFNO 的适应证、禁忌证和与 HFNO 失败相关的因素。HFNO 还可能通过在 ICU 和手术室中延长插管期间的无通气氧合来减少拔管后 ARF 患者需要气管插管。此外，HFNO 被提议通过在 ICU 和手术室中延长插管期间的无通气氧合来限制氧饱和度降低。
