From the Research
For post-intubation sedation, ketamine is typically dosed at 0.5-2 mg/kg/hr as a continuous infusion, while midazolam (Versed) is usually administered at 0.02-0.1 mg/kg/hr, with careful consideration of the most recent evidence from 1 that suggests adjunctive ketamine may have a moderate meaningful net benefit. When considering the use of ketamine and midazolam for post-intubation sedation, it is essential to prioritize the most recent and highest quality evidence. The study by 1 provides the most up-to-date information on the effectiveness of ketamine as adjunctive or monotherapy for post-intubation sedation in patients with trauma on mechanical ventilation. Key points to consider when using ketamine and midazolam for post-intubation sedation include:
- Initial bolus dosing before starting the infusion is often helpful: ketamine 0.5-1 mg/kg IV and midazolam 0.02-0.05 mg/kg IV.
- Dosing should be individualized based on patient response, with careful titration to achieve the desired level of sedation while monitoring for side effects.
- Lower doses are recommended for elderly patients or those with hepatic or renal impairment.
- Regular sedation assessment using validated scales (such as RASS or SAS) should guide dose adjustments.
- Ketamine may cause increased heart rate and blood pressure, while midazolam can cause respiratory depression and hypotension, particularly in volume-depleted patients.
- Both medications can accumulate with prolonged use, potentially delaying emergence from sedation when discontinued. It is also important to note that the use of higher doses of ketamine (> 2 mg/kg) has been associated with increased odds of adverse events, including hypotension, laryngospasm, bradycardia, repeat medications, oxygen desaturation, multiple attempts, and failed airway, as reported in the study by 2. Therefore, careful consideration of the potential risks and benefits of using ketamine and midazolam for post-intubation sedation is crucial.