意大利米兰圣心天主教大学Domenico L. Grieco团队比较了头盔式无创通气与高流量鼻氧对COVID-19和中重度低氧性呼吸衰竭患者无呼吸支持天数的影响。2021年3月25日，该研究发表在《美国医学会杂志》上。

高流量鼻腔吸氧是急性低氧性呼吸衰竭的首选治疗方法，广泛应用于COVID-19患者。

为了评估头盔式无创通气与单用高流量鼻氧比较，是否能增加COVID-19患者的无呼吸支持天数，2020年10月至12月，研究组在意大利4个重症监护室（ICU）进行了一项多中心随机临床试验，包括109名COVID-19和中重度低氧性呼吸衰竭患者（动脉氧分压与吸入氧分数之比≤200）。将参与者随机分组，其中54例采用头盔式无创通气持续治疗至少48小时，随后接受高流量鼻氧；55例患者仅接受高流量鼻氧治疗。主要结局是登记后28天内没有呼吸支持的天数。

110例患者中有109例（99%）完成了试验，中位年龄为65岁，女性占19%。头盔组患者随机分组后28天内无呼吸支持的中位天数为20天，高流量鼻氧组为18天，差异无统计学意义。在9个预先指定的次要结局中，有7个无显著差异。头盔组的气管插管率为30%，明显低于高流量鼻氧组（51%）。头盔组28天内中位无创机械通气为28天，显著高于高流量鼻氧组（25天）。头盔组的住院死亡率为24%，高流量鼻氧组为25%，差异不显著。

研究结果表明，对于COVID-19和中重度低氧血症患者，采用头盔式无创通气治疗与高流量鼻氧治疗相比，28天内无呼吸支持天数无显著差异。

附：英文原文

Title: Effect of Helmet Noninvasive Ventilation vs High-Flow Nasal Oxygen on Days Free of Respiratory Support in Patients With COVID-19 and Moderate to Severe Hypoxemic Respiratory Failure: The HENIVOT Randomized Clinical Trial

Author: Domenico Luca Grieco, Luca S. Menga, Melania Cesarano, Tommaso Rosà, Savino Spadaro, Maria Maddalena Bitondo, Jonathan Montomoli, Giulia Falò, Tommaso Tonetti, Salvatore L. Cutuli, Gabriele Pintaudi, Eloisa S. Tanzarella, Edoardo Piervincenzi, Filippo Bongiovanni, Antonio M. Dell’Anna, Luca Delle Cese, Cecilia Berardi, Simone Carelli, Maria Grazia Bocci, Luca Montini, Giuseppe Bello, Daniele Natalini, Gennaro De Pascale, Matteo Velardo, Carlo Alberto Volta, V. Marco Ranieri, Giorgio Conti, Salvatore Maurizio Maggiore, Massimo Antonelli, COVID-ICU Gemelli Study Group, Gian Marco Anzellotti, Laura Cascarano, Francesca Ceccaroni, Paolo De Santis, Mariangela Di Muro, Miriana Durante, Nicoletta Filetici, Veronica Gennenzi, Antonio Gullì, Gianmarco Lombardi, Alessio Maccaglia, Riccardo Maviglia, Alessandro Mele, Giovanna Mercurio, Teresa Michi, Tony C. Morena, Martina Murdolo, Mariano Alberto Pennisi, Stefania Postorino, Antonella Potalivo, Francesca Pozzana, Carlotta Rubino, Martina Savino, Roberta Scarascia, Angela Scavone, Donatella Settanni, Serena Silva, Flavia Torrini, Joel Vargas, Carmelina Zaccone

Issue&Volume: 2021-03-25

Abstract:

Importance  High-flow nasal oxygen is recommended as initial treatment for acute hypoxemic respiratory failure and is widely applied in patients with COVID-19.

Objective  To assess whether helmet noninvasive ventilation can increase the days free of respiratory support in patients with COVID-19 compared with high-flow nasal oxygen alone.

Design, Setting, and Participants  Multicenter randomized clinical trial in 4 intensive care units (ICUs) in Italy between October and December 2020, end of follow-up February 11, 2021, including 109 patients with COVID-19 and moderate to severe hypoxemic respiratory failure (ratio of partial pressure of arterial oxygen to fraction of inspired oxygen ≤200).

Interventions  Participants were randomly assigned to receive continuous treatment with helmet noninvasive ventilation (positive end-expiratory pressure, 10-12 cm H2O; pressure support, 10-12 cm H2O) for at least 48 hours eventually followed by high-flow nasal oxygen (n=54) or high-flow oxygen alone (60 L/min) (n=55).

Main Outcomes and Measures  The primary outcome was the number of days free of respiratory support within 28 days after enrollment. Secondary outcomes included the proportion of patients who required endotracheal intubation within 28 days from study enrollment, the number of days free of invasive mechanical ventilation at day 28, the number of days free of invasive mechanical ventilation at day 60, in-ICU mortality, in-hospital mortality, 28-day mortality, 60-day mortality, ICU length of stay, and hospital length of stay.

Results  Among 110 patients who were randomized, 109 (99%) completed the trial (median age, 65 years [interquartile range {IQR}, 55-70]; 21 women [19%]). The median days free of respiratory support within 28 days after randomization were 20 (IQR, 0-25) in the helmet group and 18 (IQR, 0-22) in the high-flow nasal oxygen group, a difference that was not statistically significant (mean difference, 2 days [95% CI, 2 to 6]; P=.26). Of 9 prespecified secondary outcomes reported, 7 showed no significant difference. The rate of endotracheal intubation was significantly lower in the helmet group than in the high-flow nasal oxygen group (30% vs 51%; difference, 21% [95% CI, 38% to 3%]; P=.03). The median number of days free of invasive mechanical ventilation within 28 days was significantly higher in the helmet group than in the high-flow nasal oxygen group (28 [IQR, 13-28] vs 25 [IQR 4-28]; mean difference, 3 days [95% CI, 0-7]; P=.04). The rate of in-hospital mortality was 24% in the helmet group and 25% in the high-flow nasal oxygen group (absolute difference, 1% [95% CI, 17% to 15%]; P>.99).

Conclusions and Relevance  Among patients with COVID-19 and moderate to severe hypoxemia, treatment with helmet noninvasive ventilation, compared with high-flow nasal oxygen, resulted in no significant difference in the number of days free of respiratory support within 28 days. Further research is warranted to determine effects on other outcomes, including the need for endotracheal intubation.

DOI: 10.1001/jama.2021.4682

Source: https://jamanetwork.com/journals/jama/fullarticle/2778088