The aim of the study is to compare the use of dexmedetomidine + ketamine with dexmedetomidine + placebo for sedation in ICU patients in terms of safety and efficacy

Inclusion Criteria:

• Age between 18-80 years old
• Admitted to Intensive care unit at LAUMCRH
• Need for sedation for at least 24 hours
• Informed Consent Form signed by patient or surrogate

Exclusion Criteria:

• Pregnant patients
• At risk of increased intracranial pressure
• Aortic dissection
• Acute coronary syndrome
• Hypertension (SBP > 180 mmHg)
• Chronic alcoholism
• Acute alcohol intoxication
• Alcohol withdrawal
• Refractory status epilepticus
• History of psychiatric disorder
• Known allergy or contraindication to use of dexmedetomidine or ketamine
• Baseline hypotension (MAP<65 mmHg)
• Baseline bradycardia (HR<48 bpm)
• Patients receiving neuromuscular blocking agents
• Patients requiring deep sedation as determined by the ICU attending