The effects of a 2-h trial of high-flow oxygen by nasal cannula versus Venturi mask in immunocompromised patients with hypoxemic acute respiratory failure: a multicenter randomized trial

Abstract

Introduction: In immunocompromised patients, acute respiratory failure (ARF) is associated with high mortality, particularly when invasive mechanical ventilation (IMV) is required. In patients with severe hypoxemia, high-flow nasal oxygen (HFNO) therapy has been used as an alternative to delivery of oxygen via a Venturi mask. Our objective in the present study was to compare HFNO and Venturi mask oxygen in immunocompromised patients with ARF.

Methods: We conducted a multicenter, parallel-group randomized controlled trial in four intensive care units. Inclusion criteria were hypoxemic ARF and immunosuppression, defined as at least one of the following: solid or hematological malignancy, steroid or other immunosuppressant drug therapy, and HIV infection. Exclusion criteria were hypercapnia, previous IMV, and immediate need for IMV or noninvasive ventilation (NIV). Patients were randomized to 2 h of HFNO or Venturi mask oxygen.

Results: The primary endpoint was a need for IMV or NIV during the 2-h oxygen therapy period. Secondary endpoints were comfort, dyspnea, and thirst, as assessed hourly using a 0-10 visual analogue scale. We randomized 100 consecutive patients, including 84 with malignancies, to HFNO (n = 52) or Venturi mask oxygen (n = 48). During the 2-h study treatment period, 12 patients required IMV or NIV, and we found no significant difference between the two groups (15 % with HFNO and 8 % with the Venturi mask, P = 0.36). None of the secondary endpoints differed significantly between the two groups.

Conclusions: In immunocompromised patients with hypoxemic ARF, a 2-h trial with HFNO improved neither mechanical ventilatory assistance nor patient comfort compared with oxygen delivered via a Venturi mask. However, the study was underpowered because of the low event rate and the one-sided hypothesis.

Trial registration: ClinicalTrials.gov identifier: NCT02424773 . Registered 20 April 2015.

Fig. 1

Patient flowchart. HFNO high-flow nasal oxygen, ICU intensive care unit, IMV invasive mechanical ventilation, NIV noninvasive ventilation, VAS visual analogue scale

Fig. 2

Changes in dyspnea, thirst and discomfort during the 2-h study period. Dyspnea (panel a), thirst (panel b) and discomfort (panel c) were assessed using 0–10 visual analogue scales on which 0 indicated absence of dyspnea, thirst, or discomfort and 10 signified the worst possible dyspnea, thirst, or discomfort. The open bars represent the high-flow nasal oxygen group and the gray bars the Venturi mask group

Fig. 3

Respiratory rate (panel a) and heart rate (panel b) changes during the 2-h study period. The open bars represent the high-flow nasal oxygen group and the gray bars the Venturi mask group. ∆60-0 indicates the difference between randomization and the 1-h time point. ∆120-60 indicates the difference between the 1-h and 2-h time points. ∆120-0 indicates the difference between randomization and the 2-h time point