inclusion criteria: ≥ 18 years of age; mechanically ventilated and expected to remain mechanically ventilated at the end of the next day; receiving iv sedation by infusion or bolus for ≤72 hours to facilitate mechanical ventilation. transferred patients with escalating ventilation needs are eligible for recruitment within ≤72 hours of sedation commenced within the participating trial site that they were transferred to. note: intravenous sedation required to support mechanical ventilation includes use of one or more of the following agents: benzodiazepines, propofol, ketamine, barbiturates, alpha-2 agonist, opioids. patients receiving intravenous opioids only i.e., fentanyl ≥ 50mcg/hour, hydromorphone ≥ 0.4mg/hour (or bolus q1h) for analgesia and sedation or agitation to assist mechanical ventilation are eligible for inclusion. a) proven or suspected (under investigation) covid-19, or b) covid-19 negative patients who have a pao2fio2 ratio ≤300 measured with arterial blood gas at least once during the 12 hours prior to enrollment.

inclusion criteria: ≥ 18 years of age; mechanically ventilated and expected to remain mechanically ventilated at the end of the next day; receiving iv sedation by infusion or bolus for ≤72 hours to facilitate mechanical ventilation. transferred patients with escalating ventilation needs are eligible for recruitment within ≤72 hours of sedation commenced within the participating trial site that they were transferred to. note: intravenous sedation required to support mechanical ventilation includes use of one or more of the following agents: benzodiazepines, propofol, ketamine, barbiturates, alpha-2 agonist, opioids. patients receiving intravenous opioids only i.e., fentanyl ≥ 50mcg/hour, hydromorphone ≥ 0.4mg/hour (or bolus q1h) for analgesia and sedation or agitation to assist mechanical ventilation are eligible for inclusion. a) proven or suspected (under investigation) covid-19, or b) covid-19 negative patients who have a pao2fio2 ratio ≤300 measured with arterial blood gas at least once during the 12 hours prior to enrollment.

inclusion criteria: 1. ≥ 18 years of age; 2. mechanically ventilated and expected to remain mechanically ventilated at the end of the next day; 3. receiving iv sedation by infusion or bolus for ≤72 hours to facilitate mechanical ventilation. transferred patients with escalating ventilation needs are eligible for recruitment within ≤72 hours of sedation commenced within the participating trial site that they were transferred to. note: intravenous sedation required to support mechanical ventilation includes use of one or more of the following agents: benzodiazepines, propofol, ketamine, barbiturates, alpha-2 agonist, opioids. patients receiving intravenous opioids only i.e., fentanyl ≥ 50mcg/hour, hydromorphone ≥ 0.4mg/hour (or bolus q1h) for analgesia and sedation or agitation to assist mechanical ventilation are eligible for inclusion. 4. a) proven or suspected (under investigation) covid-19, or b) covid-19 negative patients who have a pao2fio2 ratio ≤300 measured with arterial blood gas at least once during the 12 hours prior to enrollment.

inclusion criteria: 1. ≥ 18 years of age; 2. mechanically ventilated and expected to remain mechanically ventilated at the end of the next day; 3. receiving iv sedation by infusion or bolus for ≤72 hours to facilitate mechanical ventilation. transferred patients with escalating ventilation needs are eligible for recruitment within ≤72 hours of sedation commenced within the participating trial site that they were transferred to. note: intravenous sedation required to support mechanical ventilation includes use of one or more of the following agents: benzodiazepines, propofol, ketamine, barbiturates, alpha-2 agonist, opioids. patients receiving intravenous opioids only i.e., fentanyl ≥ 50mcg/hour, hydromorphone ≥ 0.4mg/hour (or bolus q1h) for analgesia and sedation or agitation to assist mechanical ventilation are eligible for inclusion. 4. a) proven or suspected (under investigation) covid-19, or b) covid-19 negative patients who have a pao2fio2 ratio ≤300 measured with arterial blood gas at least once during the 12 hours prior to enrollment.

inclusion criteria: 1. ≥ 18 years of age; 2. mechanically ventilated and expected to remain mechanically ventilated at the end of the next day; 3. receiving iv sedation by infusion or bolus for ≤72 hours to facilitate mechanical ventilation. note: intravenous sedation required to support mechanical ventilation includes use of one or more of the following agents: benzodiazepines, propofol, ketamine, barbiturates, alpha-2 agonist, opioids. patients receiving intravenous opioids only i.e., fentanyl ≥ 50mcg/hour, hydromorphone ≥ 0.4mg/hour (or bolus q1h) for analgesia and sedation or agitation to assist mechanical ventilation are eligible for inclusion. 4. a) proven or suspected (under investigation) covid-19, or b) covid-19 negative patients who have a pao2fio2 ratio ≤300 measured with arterial blood gas at least once during the 12 hours prior to enrollment.

inclusion criteria: 1. ≥ 18 years of age; 2. mechanically ventilated and expected to remain mechanically ventilated at the end of the next day; 3. receiving iv sedation by infusion or bolus for ≤72 hours to facilitate mechanical ventilation. note: intravenous sedation required to support mechanical ventilation includes use of one or more of the following agents: benzodiazepines, propofol, ketamine, barbiturates, alpha-2 agonist, opioids. patients receiving intravenous opioids only i.e., fentanyl ≥ 50mcg/hour, hydromorphone ≥ 0.4mg/hour (or bolus q1h) for analgesia and sedation or agitation to assist mechanical ventilation are eligible for inclusion. 4. a) proven or suspected (under investigation) covid-19, or b) covid-19 negative patients who have a pao2fio2 ratio ≤300 measured with arterial blood gas at least once during the 12 hours prior to enrollment.

inclusion criteria: 1. adults ≥18 years of age 2. mechanically ventilated ≤ 48 hours 3. proven or suspected covid-19 disease or hypoxic respiratory failure (pao2/fio2 <= 200)

inclusion criteria: 1. adults ≥18 years of age 2. mechanically ventilated ≤ 48 hours 3. proven or suspected covid-19 disease or hypoxic respiratory failure (pao2/fio2 <= 200)