What is the Ketamine dose for analgesia during synchronized cardioversion?

• A. 0.5 mg/kg
• B. 0.25 mg/kg
• C. 0.2 mg/kg
• D. 0.1 mg/kg

Answer: (C)

Ketamine used for analgesia during synchronized cardioversion is given at a low, subanesthetic dose to provide pain relief without deep sedation. The analgesic dose that is most appropriate is 0.2 mg/kg IV. This amount offers rapid onset—typically within seconds—and a short duration that matches the brief nature of the procedure, helping prevent movement and discomfort during the shock while allowing the patient to maintain protective airway reflexes.

Lower amounts, like 0.1 mg/kg, may not provide sufficient analgesia for the pain of the procedure, while higher amounts such as 0.25 or 0.5 mg/kg increase the risk of deeper sedation, dissociation, and more pronounced hemodynamic effects. Those risks are less desirable in a cardioversion setting where airway protection and stable perfusion are important. Ketamine’s analgesic effect at this dose, plus its relatively rapid offset, makes 0.2 mg/kg a good balance for synchronized cardioversion, with IV administration and close monitoring of vitals.