Table 2: Commonly available intravenous medication used for sedation in cardioversion^15,21–23.

Sedative	Dose	Comments
Midazolam15,21,22	0.10–0.20 mg/kg once repeat 2 mg IV every 2 min as needed	Most commonly used for induction; Onset 1–2 min, duration 30 min; Small drop in blood pressure; Flumazenil antagonist available
Propofol21	1.0–2.5 mg/kg once	Onset 20–40 s, duration 5–10 min; Small drop in blood pressure; More apnoea events
Fentanyl22	1.0–1.5 μg/kg once repeat as needed	Onset 1–2 min, duration 30 min; Minimal cardiovascular depression
Etomidate22	0.2 mg/kg over 30–60 s	Onset <1 min, duration 3–5 min; Minimal cardiovascular or respiratory depression
Ketamine22,23	1.0–4.5 mg/kg (2 mg/kg) IV over 60 s	Approximately 6–12% of patients exhibit symptoms of emergence phenomenon or delirium, including hallucinations, flashbacks, unusual thoughts, extreme fear, excitement and irrational behaviour

IV = intravenous; min = minutes; s = seconds.