Please select the eligibility criteria that correspond to the clinical trial below.
Title: Effect of Prone Positioning on Mortality in Patients With Severe and Persistent Acute Respiratory Distress Syndrome
Brief Summary: We project to test the effect of prone position on mortality in severe ARDS patients (PaO2/FiO2\<150 with FiO2 \> or = 0.6 and positive end-expiratory pressure \> or = 5 cmH2O). Ventilator will be set in accordance with current standards aiming at protecting the lungs from VALI. Patients will be randomized into two arms: prone group in which proning will be realized for at least 16 hours a day and supine group in which patients will stay in a semi-recumbent position. Primary end-point is 28-day mortality of all causes. Secondary end-points are 90-day mortality of all causes and incidence of ventilator-acquired pneumonia. Study sample was calculated to detect ability of proning to reduce mortality from 60 to 45% percent, at one-tailed alpha error of 5% and power of 90% and 230 patients are needed in each arm.


Options:
A: Inclusion Criteria:

* Invasive mechanical ventilation
* Acute respiratory insufficiency (within past 28 days)
* Bilateral infiltrates on frontal chest radiograph
* Hypoxemia, defined as PaO2/FiO2\<=250

Exclusion Criteria:

* Primary cause of respiratory failure is cardiac
* Anticipated duration of mechanical ventilation \< 48 hours
* Inability to wean other experimental ventilation strategies
* Severe chronic respiratory disease
* Neuromuscular disease that will prolong mechanical ventilation
* Conditions where hypercapnia-induced intracranial hypertension should be avoided
* Morbid obesity (\> 1Kg per cm body weight)
* Pregnancy
* Very unlikely to survive and lack of commitment to life support Underlying irreversible condition with 6 month mortality \>= 50%
* Greater than 48 hours elapsed since first eligible
* Current participation in competing trial
* Lack of physician, patient or proxy consent
B: Inclusion Criteria:

* Early Acute Respiratory Distress Syndrome
* PaO2/FiO2 \< 150 mm Hg at PEEP ≥ 8 cm H2O
* Age 18-75 years
* Body weight \> 40 kg

Exclusion Criteria:

* More than 1 chest tube/hemithorax with persistent airleak for \> 72 h)
* Systolic pressure \< 90 mm Hg with fluids/norepinephrine at ≥ 0.5 μg/kg/min
* Heart disease (defined in Detailed Description)
* Chronic obstructive pulmonary disease (defined in Detailed Description)
* Intracranial abnormalities (any cause of intracranial pressure \> 20 mm Hg)
* Chronic interstitial lung disease
* Lung biopsy or resection on current admission
* Previous lung or bone marrow transplant or immunosuppression
* Pregnancy or morbid obesity
* Inability to wean from prone positioning or inhaled nitric oxide
* Enrollment in another interventional study
C: Inclusion Criteria:

1. Adult patients aged 18 years or more, both gender
2. Receiving endotracheal intubation and mechanical ventilation for less than 36 hours
3. Presenting with a Severe ARDS :

   * Acute onset
   * PaO2/FiO2 ≤ 200 (≤ 26.7 kPa)
   * Bilateral pulmonary infiltrates on frontal chest radiography
   * Capillary wedge pressure \< 18 mm Hg if measured or no evidence for left atrial hypertension
4. During since 12-24 hours
5. AND with severity criteria : PaO2/FiO2 \< 150 mm Hg (\< 20 kPa) under FiO2 ≥ 0.6, PEEP ≥ 5 cm H2O and a tidal volume equal to 6 ml/kg PBW.
6. Written consent from patient's next of kin

Exclusion Criteria:

1. contra-indication to the prone position

   * Intracranial pressure \> 30 mm Hg or cerebral perfusion pressure \< 60 mm Hg
   * Massive haemoptysis needing urgent surgical or radiological treatment
   * Tracheal or thoracic surgery in the last 15 days
   * Facial trauma or surgery in the last 15 days
   * Deep venous thrombosis or pulmonary embolism treated in the last 2 days
   * Cardiac pace maker implantation in the last 2 days
   * Unstable bone dislocations of rachis, femur, rib cage, pelvis
   * Mean systolic arterial pressure less than 70 mm Hg despite vasopressive therapy
   * Pregnancy
   * Bronchopleural fistula treated with a single anterior chest tube (risk of kinking in prone position)
2. Exclusion criteria for respiratory raisons

   * Necessity to use NOi or almitrine
   * Extra body circulation for oxygenation and/or CO2 epuration
3. Exclusion criteria linked to clinical context

   * Pulmonary transplantation
   * Burns ≥ 20% of body surface
   * Chronic respiratory insufficiency under home oxygen therapy or non invasive ventilation
   * Chronic disease supposed to be fatal in less than 1 year
   * Non invasive ventilation for more than 24 hours before enrollment
4. Other exclusion criteria

   * Decision to stop life-supportive therapies before enrollment
   * Enrollment in an other trial testing an intervention and with mortality as primary end point in the last 30 days
   * Prior enrollment in the same study
   * Prone position before enrollment
D: Inclusion Criteria:

* Acute onset of respiratory failure, with fewer than 2 weeks of new pulmonary symptoms;
* Endotracheal intubation or tracheostomy;
* Hypoxaemia - defined as a partial pressure of oxygen in arterial blood (PaO2)/fraction of inspired oxygen (FiO2) less than or equal to 200mmHg on FiO2 greater than or equal to 0.5, regardless of positive end expiratory pressure (PEEP)
* Bilateral alveolar consolidation (airspace disease) seen on frontal chest radiograph

In addition, to qualify for randomization, patients are assessed on the following ventilator settings:

* Mode: pressure control or volume control or pressure support
* FiO2 greater than 0.6 (or higher if necessary to keep pulse oximetric saturation \[SpO2\] greater than 90%)
* PEEP greater than 10 cm H2O (or greater if necessary to keep SpO2 greater than 90%)
* Tidal volume 6 ml/kg predicted body weight (PBW)

After at least 30 minutes on these settings, we sample arterial blood to assess oxygenation. If PaO2 is less than or equal to 200 mmHg, the patient qualifies for randomization; if PaO2/FiO2 greater than 200 mmHg, standardized hypoxaemia assessments are repeated at least once daily for the following 72 hours (providing eligibility criteria are still met).

Exclusion Criteria:

* Remaining duration of mechanical ventilation less than 48 hours, as judged by the attending physician
* Primary cause of acute respiratory failure judged by attending physician to be circulatory overload due to, for example, congestive heart failure, hyper-resuscitation, or need for dialysis
* Suspected pulmonary haemorrhage syndrome
* Lack of commitment to ongoing life support (note that this does not include the presence of a "Do Not Resuscitate" order alone, if there is a commitment to ongoing life support
* Aged less than 16 years or greater than 85 years
* Weight less than 35 kg
* Severe chronic respiratory disease, as indicated by any of:
* Baseline forced expiratory volume in one second (FEV1) less than 20 ml/kg predicted body weight
* Pre-existing chronic interstitial lung disease with chronic interstitial infiltration on chest x-ray
* Documented chronic carbon dioxide (CO2) retention (partial pressure of carbon dioxide in arterial blood \[PaCO2\] less than 50 mmHg) and/or chronic hypoxaemia(PaO2 less than 55 mmHg on FiO2=0.21)
* Chronic restrictive, obstructive, neuromuscular, chest wall or pulmonary vascular disease resulting in severe exercise restriction (e.g., unable to climb stairs or perform household duties), secondary polycythaemia, severe pulmonary hypertension (mean pulmonary arterial pressure \[PAP\] greater than 40 mmHg), or ventilator dependency
* Morbid obesity - defined as greater than 1 kg/cm body height
* Underlying pre-existing condition with expected 6-month mortality greater than 50%
* Neurological conditions with risk of intracranial hypertension (where hypercapnia should be avoided)
* Neuromuscular disease that will result in prolonged need for mechanical ventilation, including (but not limited to):
* Guillain Barre syndrome
* Cervical spinal cord injury
* Previous randomization in this trial
* All inclusion criteria present for greater than 73 hours in study intensive care unit (ICU)
* On HFO at the time of screening

Answer: C