The purpose of this study is to estimate the hypothesized benefit of sedation interruption protocol on mechanical ventilation duration and PICU length of stay. The study will evaluate recruitment rates, and adherence rates of such protocol.

This is a prospective single-center, superiority, open randomized controlled trial comparing sedation interruption protocol and routine continuous sedation in mechanically ventilation (MV) children.

The study will be conducted in the twelve beds Pediatric Intensive Care Unit (PICU) at the Montreal Children's Hospital, a pediatric tertiary care and teaching hospital.

Patients will be enrolled prospectively within 24 hours of intubation and MV. After obtaining written consent patients will then be randomized to interrupted sedation or standard sedation protocol. The investigators will randomize using a computer-generated sequence of random numbers.

A Sedation protocol will be used for both groups to adjust continuous infusions of sedatives/analgesics to a targeted Comfort-Behavior scale. In the intervention group, sedation infusions will be interrupted daily at 8:00 AM, this interruption will be continued until the patient is under-sedated according to the Comfort Behavior scale goals or in the presence of symptoms of hemodynamic instability or respiratory distress. Then the patient will receive a bolus of sedation and the infusion will be restarted at a dose 50% less than the previous dose to return to the Comfort Score goal.

Inclusion Criteria:

• Intubated and mechanically ventilated patients due to respiratory failure of multiple etiologies or after major surgical procedures for more than 24 hours.
• Sedation managed by benzodiazepines and opioids infusions

Exclusion Criteria:

• If sedation is required as part of medical management (Pulmonary hypertension, Increase intracranial pressure, Seizures
• Trauma & burn admissions
• Patients resuscitated from cardiac arrest
• Allergy to sedation (midazolam)
• Allergy to analgesia (fentanyl, morphine)
• Difficult airway including post-operative airway surgeries. (As deemed by ICU physician in charge)
• High frequency oscillator
• Special gas as inhaled nitric oxide, or isoflurane.
• Chronic ventilatory support
• Neuromuscular diseases
• Corrected Gestational age less than 37 weeks.
• Patients not expected to survive to discharge as per attending physician.
• Palliative care patients.