What is the recommended dose of ketamine infusion for sedation?

Ketamine Infusion Dosing for Sedation

For procedural sedation, administer ketamine at 1.5-2 mg/kg IV bolus, which provides effective sedation in the emergency department and procedural settings. 1

Intravenous Bolus Dosing

The standard IV dose of 1.5-2 mg/kg is significantly more effective than lower doses, with only 5.5% of patients requiring additional doses compared to 54% when using 1.0 mg/kg. 1 This dosing has been validated in multiple emergency department studies for procedural sedation and analgesia. 2

Low-Dose Alternative Approach

For select patients, lower doses of 0.5-1.0 mg/kg IV may provide adequate sedation, particularly in pediatric populations:

• 88% of pediatric patients achieved successful sedation with initial doses ≤1 mg/kg 3
• 44% required only 0.75 mg/kg or less 3
• 25% achieved adequate sedation with just 0.5 mg/kg 3

However, this approach requires careful titration with additional 0.25-0.5 mg/kg aliquots as needed. 3

Continuous Infusion Dosing

For pain management in critically ill adults, use 0.5 mg/kg IV bolus followed by 1-2 μg/kg/min continuous infusion as an adjunct to opioid therapy. 1, 4

Alternative infusion protocols include:

• Emergency department pain management: 15 mg IV bolus followed by 20 mg/hour infusion for 1 hour 5
• Pediatric ICU sedation: 0.5-1.0 mg/kg bolus followed by 10-15 μg/kg/min continuous infusion 6
• Perioperative setting: Maximum 0.5 mg/kg/hour after induction, with continuous infusion at 0.125-0.25 mg/kg/hour 7

Onset and Duration

IV ketamine has rapid onset of 30-96 seconds, allowing immediate procedural intervention. 1 Average recovery time is approximately 84 minutes (range 22-215 minutes). 1

Intramuscular Dosing

For pediatric procedural sedation when IV access is unavailable, use 4 mg/kg IM with repeat doses of 2-4 mg/kg after 5-10 minutes if needed. 1 IM administration combined with 0.01 mg/kg atropine results in faster onset (3 minutes vs 18 minutes) compared to other sedatives. 1

Critical Monitoring Requirements

Continuous monitoring of oxygen saturation, heart rate, and blood pressure is mandatory during ketamine administration. 1, 7 Practitioners must be able to identify and rescue patients from unintended deep sedation or general anesthesia. 7 Maintain vascular access throughout the procedure until the patient is no longer at risk for cardiorespiratory depression. 7

Target oxygen saturation >93% on room air during the procedure. 1

Common Adverse Effects

• Mild recovery agitation: 17.6% of patients 1
• Moderate-to-severe agitation: 1.6% 1
• Emesis without aspiration: 6.7% 1
• Respiratory depression requiring intervention: Rare but possible, requiring bag-valve-mask ventilation in some cases 2

Critical Contraindications

Avoid ketamine in patients with:

• Ischemic heart disease 1, 7
• Cerebrovascular disease 1
• Uncontrolled hypertension 1
• Active psychosis 7
• Severe hepatic dysfunction 1
• Elevated intracranial or intraocular pressure 1, 7

Combination Therapy Considerations

Ketamine combined with midazolam (0.05-0.1 mg/kg) provides equally effective sedation with potentially reduced emergence reactions, though studies show mixed results on whether midazolam significantly reduces agitation. 2 The combination of 0.07 mg/kg midazolam followed by 2 mg/kg ketamine provides effective procedural sedation in adults. 2