Please select the eligibility criteria that correspond to the clinical trial below.
Title: N/A
Brief Summary: Patients undergoing open appendectomy for acute appendicitis were enrolled in a randomized prospective study.


Options:
A: Inclusion Criteria:

* Consent was given
* 15 years old or older
* Underwent acute appendicitis

Exclusion Criteria:

* Lack of follow up
* Younger than 15 years
* Not eligible according to physician decision
B: Inclusion Criteria:

* Major patients with mechanical ventilation
* ARDS according to Berlin definition:Hypoxemia defined with PaO2 FiO2 ratio less or equal to 300 mmHg with Positive End Expiratory Pressure higher or equal to 5 cmH20, Less than seven days between a known clinical insult or new or worsening of respiratory symptoms, Bilateral opacities on chest Imaging not fully explained by effusions, lobar or lung collapse, or nodules, Respiratory failure not fully explained by cardiac failure or fluid overload
* Less than twelve hours following initiation of mechanical ventilation.

Exclusion Criteria:

* Pregnancy
* Patient less than 18 years old
* Sickle cell disease
* Patient deprived of freedom, Under a legal protective measure
* Cardiac arrest as the reason for ICU hospitalisation
* Traumatic brain injury as the reason for ICU hospitalisation
* Hemoptysis with embolization or surgery
* Extracorporeal life support or Extracorporeal Membrane Oxygenation before randomization
* Chronic Obstructive Pulmonary Disease with oxygen or non invasive ventilation at home (obstructive sleep apnoea syndrome is not an exclusion criteria)
* Patient with very high risk of death with IGS II (Simplified Severity Index II) than 90
* Indication of hyperbaric oxygenation : carbon monoxide intoxication, gas embolism, necrotizing fasciitis
* Cyanide intoxication, methemoglobinemia
* Untreated pneumothorax
* Lymphangitis carcinomatosa
* Eosinophilic pneumonia
* Intensive care management for organ donation
* Participation in another interventional study with mortality as a major outcome to avoid confounding factor
* Patient not affiliated to social security
C: Inclusion Criteria:

* Acutely admitted to the ICU AND
* Aged ≥ 18 years AND
* Receives supplemental oxygen with a flow of at least 10 L per minutes in an open system including high-flow systems OR at least a FiO2 of 0.50 in a closed system including invasive or non-invasive ventilation or CPAP systems AND
* Expected to receive supplemental oxygen for at least 24 hours in the ICU AND
* Having an arterial line for PaO2 monitoring

Exclusion Criteria:

* Cannot be randomised within twelve hours after present ICU admission
* Chronic mechanical ventilation for any reason
* Use of home oxygen
* Previous treatment with bleomycin
* Organ transplant during current hospital admission
* Withdrawal from active therapy or brain death deemed imminent
* Fertile woman (\< 50 years of age) with positive urine human gonadotropin (hCG) or plasma-hCG
* Carbon monoxide poisoning
* Cyanide poisoning
* Methaemoglobinaemia
* Paraquat poisoning
* Any condition expected to involve the use of hyperbaric oxygen (HBO)
* Sickle cell disease
* Consent not obtainable according to national regulations
* Previously randomised into the HOT-ICU trial
D: Inclusion Criteria:

1. Age ≥ 18 years
2. Receiving mechanical ventilation through an endotracheal tube or tracheostomy
3. Admitted to the study ICU or admission to the study ICU from the emergency department is planned

Exclusion Criteria:

1. Known pregnancy or beta hCG level greater than the laboratory upper limit of normal in a patient capable of becoming pregnant
2. Known to be a prisoner

Answer: A