Drowning-related Acute Respiratory Failure

The purpose of this study is to assess the Non-Invasive Ventilation-Continuous Positive Airway Pressure efficacy (experimental group) for drowning related Acute Respiratory Failure compared to Oxygen Supply by face mask (15Liters/minutes) (control group).

Open-label, multicenter, prospective, cross-over cluster randomized (ratio 1:1), conducted in 16 Emergency Medical Service centers in France :

* Experimental group: Non-Invasive Ventilation-Continuous Positive Airway Pressure (Arm 1)
* Control group: Oxygen Supply by face mask (Arm 2)

Drowning-related acute respiratory failure has important clinical consequences (4 to 18% mortality). No national/international medical consensus exist for its management.

Our team has successively demonstrated that:

* The acute respiratory failure related to drowning in salt or fresh water presented the same clinical pathway and prognosis ;
* Most victims with drowning related acute respiratory failure do no present hemodynamic instability ;
* If the oxygenation is rapidly improved, neurological status is also maintained in acute respiratory failure victims ;
* Pediatric and adult presentations are similar.

Facing an acute respiratory failure, emergency medical service must rapidly choose between oxygen supply by face mask (15 liters /minutes), mechanical ventilation or non-invasive ventilation. mechanical ventilation as non-invasive ventilation present interests and side arms. No comparative study has been conducted between these strategies. The arguments for non-invasive ventilation use specifically in a continuous positive airway pressure mode are:

* Fast recovery of acute respiratory failure in 24h
* Retrospective publications showing that the benefit of non-invasive ventilation probably based on continuous positive airway pressure mode
* Easy implementation of continuous positive airway pressure in the pre-hospital setting (adults, children, newborns)
* Complexity of mechanical ventilation in pre-hospital setting. Our working hypothesis is the efficacy of early use of non-invasive ventilation-continuous positive airway pressure in drowning related acute respiratory failure.

Eligibility Criteria:
Inclusion Criteria:

* Man/boy or woman/girl, 1yo and older.
* Subject suffering from drowning related-Acute Respiratory Failure (whatever the nature of water, salt or fresh) and benefiting from the Emergency Medical Service intervention;
* Acute Respiratory Failure defined as the presence of:

  * Capillary O2 saturation \<92% upon Emergency Medical Service first clinical analysis at the drowning scene;
  * Need for oxygen supply 15Liters/minutes to reach capillary O2 saturation ≥ 95%;
  * Combination of Acute Respiratory Failure clinical signs: at least 1 of the following items: respiratory rate \>30/min, sternal or clavicular indrawing, abdominal breathing, cyanosis.
* Individual affiliated to or beneficiary of a French health insurance system;
* Individual with the ability to benefit from the two strategies (ambivalence clause);
* Adult Individual having signed written informed consent or child subject with an authorization of the parents.

Exclusion Criteria:

* Individual with hypothermia ≤ 34°C ;
* Individual with neurological distress defined by a Glasgow Coma Scale \< 13 at first clinical assessment and during the first 15 minutes of care ;
* Individual with hemodynamic distress defined by a systolic blood tension \< 90 mmHg at first clinical assessment and during the first 15 minutes of care ;
* Cardiac arrest or respiratory arrest ;
* Declared pregnancy or breastfeeding ;
* Patient under legal protection regime for adults.