CARDIOPULMONARY RESUSCITATION AND OTHER EMERGENCIES: Edited by Marek A. MirskiAcute respiratory failure: nonintubation assist methods for the acutely deteriorating patientFrat, Jean-Pierrea,b; Marie, Damiena; Thille, Arnaud W.a,bAuthor Information aCHU de Poitiers, Médecine Intensive Réanimation, Poitiers bINSERM CIC 1402 - ALIVE, Université de Poitiers, Faculté de Médecine et Pharmacie, Poitiers, France Correspondence to Jean-Pierre Frat, MD, Médecine Intensive Réanimation, CHU de Poitiers, 2 rue la Milétrie, 86021 Poitiers Cedex, France. Tel: +33 549444007; e-mail: [email protected] Current Opinion in Critical Care: December 2019 - Volume 25 - Issue 6 - p 591-596 doi: 10.1097/MCC.0000000000000670 Buy Metrics Abstract Purpose of review Noninvasive ventilation is strongly recommended in acute hypercapnic respiratory failure, whereas high-flow nasal oxygen therapy could be an alternative in de novo respiratory failure. Recent findings High-flow nasal oxygen may improve the outcome of patients de novo respiratory failure as compared with standard oxygen. Its success within 2 h after initiation is well predicted by a ROX index (ratio of SpO2/FiO2 to respiratory rate) greater than 4.88, as failure when less than 3.85 at 12 h after initiation. However, the superiority of high-flow nasal oxygen to standard oxygen has not been confirmed in immunocompromised patients. Although noninvasive ventilation may be deleterious through barotrauma in patients with de novo respiratory failure, its use seems to be an optimal strategy for preoxygenation before intubation in preventing severe hypoxemia in most hypoxemic patients. In mild hypoxemic patient, high-flow nasal oxygen may be more efficient than bag-valve mask in preventing severe adverse events. After anesthetic induction further positive-pressure ventilation can better secure intubation procedure than absence of ventilation. Summary Despite the growing use of high-flow nasal oxygen, new studies are needed to confirm its superiority to standard oxygen in de novo respiratory failure and others causes of acute respiratory failure in place of standard oxygen. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.