Fuller Gordon W, Keating Samuel, Goodacre Steve, Herbert Esther, Perkins Gavin, Rosser Andy, Gunson Imogen, Ward Matthew, Miller Josh, Bradburn Mike, Thokala Praveen, Harris Tim, Marsh Maggie, Scott Alex, Cooper Cindy
University of Sheffield.
University of Warwick.
Br Paramed J. 2019 Dec 1;4(3):53-54. doi: 10.29045/14784726.2019.12.4.3.53.
Acute respiratory failure (ARF) is a common and life-threatening medical emergency. Continuous positive airway pressure (CPAP) is a potentially beneficial alternative treatment; however, it is uncertain whether this could improve important outcomes in NHS ambulance services. The ACUTE study aimed to assess the feasibility of a large-scale pragmatic trial of pre-hospital CPAP.
The study was a pilot randomised controlled trial of the O-Two system CPAP mask versus standard oxygen therapy, with concealed allocation in identical sealed boxes. Feasibility objectives estimated the incidence of eligible patients; the proportion recruited and allocated to treatment appropriately; adherence to allocated treatment; and retention and data completeness. The primary clinical endpoint was 30-day mortality. Ancillary studies included an ARF incidence study, ARF diagnostic agreement study, clinician perceptions of CPAP mixed methods study and investigation of allocation concealment.
Over 12 months, 77 patients were enrolled (target 120). CPAP was fully delivered in 74% (target 75%). There were no major protocol violations/non-compliances. Full data were available for all key outcomes (targets ≥ 90%). Thirty-day mortality was 27.3%. Of deceased patients, 14/21 (68%) either did not have a respiratory condition or had ceiling of treatment decisions implemented excluding hospital NIV and critical care.
The ACUTE trial recruitment rate was below the target rate and feasibility was not demonstrated. Identification of patients who might benefit from pre-hospital CPAP was challenging. It appeared difficult to exclude conditions where CPAP would not work, or might be harmful, and to select appropriate patients where there was a meaningful chance of success, or where the potential advantages of pre-hospital CPAP would outweigh the burdens of more advanced and aggressive treatment. The limited compliance with CPAP, and the difficulty in identifying patients who could benefit from CPAP, indicate that pre-hospital CPAP is unlikely to materially reduce mortality. A definitive effectiveness trial of CPAP in the NHS is therefore not recommended.
急性呼吸衰竭（ARF）是一种常见且危及生命的医疗急症。持续气道正压通气（CPAP）是一种可能有益的替代治疗方法；然而，在英国国民医疗服务体系（NHS）的救护服务中，这是否能改善重要结局尚不确定。ACUTE研究旨在评估院前CPAP大规模实用试验的可行性。
该研究是一项关于O-Two系统CPAP面罩与标准氧疗的试点随机对照试验，采用在相同密封盒中进行隐蔽分配的方式。可行性目标包括估计符合条件患者的发生率；招募并适当分配至治疗组的比例；对分配治疗的依从性；以及保留率和数据完整性。主要临床终点是30天死亡率。辅助研究包括ARF发病率研究、ARF诊断一致性研究、临床医生对CPAP的混合方法研究以及分配隐蔽性调查。
在12个月期间，共纳入77例患者（目标为120例）。74%的患者完全接受了CPAP治疗（目标为75%）。没有重大的方案违规/不依从情况。所有关键结局均有完整数据（目标≥90%）。30天死亡率为27.3%。在死亡患者中，14/21（68%）要么没有呼吸系统疾病，要么实施了包括不进行医院无创通气和重症监护在内的治疗上限决定。
ACUTE试验的招募率低于目标率，且未证明其可行性。识别可能从院前CPAP中获益的患者具有挑战性。似乎难以排除CPAP无效或可能有害的情况，以及选择有显著成功机会或院前CPAP潜在优势超过更高级和积极治疗负担的合适患者。对CPAP的依从性有限，以及难以识别能从CPAP中获益的患者，表明院前CPAP不太可能实质性降低死亡率。因此，不建议在NHS中进行CPAP的确定性有效性试验。
