Adjunct Methadone to Decrease the Duration of Mechanical Ventilation in the Medical Intensive Care Unit

Adjunct Methadone to Decrease the Duration of Mechanical Ventilation in the Medical Intensive Care Unit

Adjunct Methadone to Decrease the Duration of Mechanical Ventilation in the Medical Intensive Care Unit

The purpose of this study is to determine if administering methadone to mechanically ventilated patients in the medical intensive care unit (ICU) requiring continuous infusions of sedatives and analgesics will decrease the time of mechanical ventilation, when initiated within 48 hours of their admission. Patients meeting enrollment criteria will be randomly assigned to receive methadone or placebo in addition to standard care. Methadone is a long acting pain medication that is approved by the Food and Drug Administration (FDA) to manage withdrawal from opioids and moderate to severe pain. Both of these indications are a frequent concern for critically ill patients that require mechanical ventilation. These patients often require intravenous (IV) opioids to manage the pain they experience due to their illness, procedures, and mechanical ventilation. During this time patients can develop physical dependence, which leads to withdrawal symptoms when the opioids are stopped or the dose is reduced. These symptoms can include agitation, pain, diarrhea and several others. Currently this is managed by a slow reduction in the dose of the IV opioid, but this can lead to prolonged time on mechanical ventilation, which has been associated with increased morbidity. Administering oral methadone to patients experiencing withdrawal symptoms has been shown to reduce and even eliminate these symptoms in the outpatient setting. This should also benefit patients in the ICU experiencing withdrawal from intravenous opioids required during their stay. It may allow for the other opioids to be discontinued more quickly, allowing for a shorter duration of mechanical ventilation. The level of pain and sedation will be assessed between groups randomized to either methadone or placebo in addition to current intravenous sedative and analgesic agents. The duration of mechanical ventilation will be assessed between both groups. Opioid withdrawal symptoms may manifest or be mistaken for delirium symptoms. ICU delirium is often managed with antipsychotic medications. To assess if methadone can reduce the need for antipsychotic medication, all administered antipsychotic doses will be recorded and total consumption will be compared between the two groups. Methadone has been associated with abnormal heart rhythms in rare instances. To ensure patient safety, data from the heart monitor will be collected and compared between the two groups to assess for QT interval prolongation.

Iatrogenic opioid abstinence syndrome, Methadone, Mechanical ventilation, ICU delirium, Continuous sedation

Methadone will be administered at a dose calculated from the subjects total daily opioid requirements, with a maximum methadone dose of 60 mg per day. The methadone will be administered every 8 hours as 5 mg capsules that will be given via an enteral feeding tube.

This will be a capsule containing only lactose and will be given every 8 hours via an enteral feeding tube. The number of placebo capsules will be calculated based on the subjects opioid requirements. This will ensure the same number of capsules will be given despite which arm the patient is enrolled in.

Levels of pain and sedation will be assessed per institutional policy, which utilizes the Motor Agitation Assessment Scale (MAAS). Average daily scores will be collected and compared for each group.

QTc intervals will be calculated and documented at baseline and every 24 hours after to ensure it does not become prolonged. These values will be compared between groups.

The number of doses of antipsychotic medications will be collected and compared as a surrogate marker for presumed delirium.

Doses of all benzodiazepines will be collected and compared between groups to determine if methadone reduces consumption.

Inclusion Criteria: Mechanically ventilated patients with opioid consumption greater than or equal to 1,200 mcg of fentanyl or equivalent consumption of another opioid per day during the first 48 hours of intubation. Exclusion Criteria: Allergy to methadone Admitted for head injury Admitted for seizure Seizure during admission, prior to enrollment Subjects at high risk for developing a prolonged corrected QT (QTc) interval Gastric residual volume ≥200 mL Suspected obstruction or ileus Nausea and vomiting Recent abdominal surgery Active upper or lower gastrointestinal bleeding Active order for no medications by mouth or Total parenteral nutrition (TPN) Pregnancy Subjects receiving neuromuscular blocker infusions Subjects taking antipsychotics at baseline

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