Acute respiratory failure is the leading cause of ICU admission of immunocompromized patients. In this subgroup of patients, the need for intubation and invasive mechanical ventilation occurs in about 50% of cases and is associated with very a high mortality rate, reaching 70% of cases. Therefore, noninvasive oxygenation strategies have been developed to avoid intubation.

More than 15 years ago, 2 trials have suggested that NIV could decrease intubation and mortality rates of immunocompromized patients as compared to standard oxygen through a mask. However these results have not been confirmed in a recent large trial.

HFNC is a recent and well-tolerated oxygenation technique. In a recent trial, HFNC alone could decrease mortality and intubation rates in patients with ARF as compared to NIV. Similar findings have been reported in a post-hoc analysis on immunocompromized patients excluding those with profound neutropenia. Likewise in a retrospective monocentric cohort of immunocompromized patients, we reported better outcomes with HFNC than with NIV.

Inclusion Criteria:

• Age ≥ 18

• Admission to ICU for acute respiratory failure defined by all of the following criteria:

  • Dyspnea at rest with RR ≥ 25 breaths/min
  • PaCO2 ≤ 50 mm Hg
  • PaO2/FiO2 ≤ 300 mm Hg under oxygen ≥ 10 l/min through a mask or HFNC or NIV (for patients under oxygen FiO2 will be calculated using the following formula: oxygen flow in liters per minute x 3 + 21)

• Immunosuppresion defined by 1 of the following criteria:

  • Hematological malignancy (active or remitting < 5 years)
  • Allogenic stem cell transplantation < 5 years
  • Solid cancer (active)
  • Leucopenia < 1 G/l or neutropenia ≤ 0.5 G/l after chemotherapy
  • Solid organ transplantation
  • AIDS (not only HIV)
  • Treatment with immunosuppressive or immunomodulatory drugs
  • Systemic steroids ≥ 0.5 mg/kg/d of prednisone-equivalent for ≥ 3 weeks

• Non opposition to participate obtained from the patient or their legally acceptable representative.

Exclusion Criteria:

• Contraindication of NIV (patient refusal, cardiac arrest, coma, not drained pneumothorax, unresolving vomiting, upper airways obstruction, hematemesis, severe facial trauma)
• Chronic respiratory failure with altered pulmonary function tests
• Overt cardiogenic pulmonary edema
• Urgent need for intubation
• Severe shock (vasopressors > 0.3 µg/kg/min to maintain SAP > 90 mm Hg)
• Impaired consciousness (Glasgow coma scale score ≤ 12) or agitation
• Surgery under general anesthesia < 7 days
• Previously included in the trial
• Do-not-intubate order
• Pregnancy or breastfeeding
• Persons benefiting from enhanced protection, namely minors, persons deprived of their liberty by a judicial or administrative decision, persons staying in a health or social institution, adults under legal protection