From the Guidelines
The recommended intramuscular (IM) dose of ketamine is 4 mg/kg, as supported by the study by Green et al 1. This dose is typically used for procedural sedation and analgesia in children. When administering ketamine IM, it is essential to inject it deeply into a large muscle, such as the gluteal muscle or lateral thigh. The onset of action occurs within 3-4 minutes, with peak effects at 10-15 minutes, and the duration of action is typically 30-60 minutes.
Some key points to consider when using ketamine IM include:
- Monitoring equipment should be ready and available to ensure patient safety
- The patient should be positioned to maintain airway patency
- Consider pretreatment with an anticholinergic like glycopyrrolate (0.01 mg/kg) to reduce secretions
- Ketamine can cause dissociative anesthesia, increased blood pressure, heart rate, and respiratory secretions
It is also important to note that the study by McCarty et al 1 found that IM ketamine had a slower onset of action compared to IV ketamine, but both routes allowed for adequate sedation for fracture and/or joint reduction without serious adverse effects. Additionally, the study by Green et al 1 found that recovery agitation was associated with higher ASA status and decreasing age, while emesis was associated with increasing age.
Overall, the use of ketamine IM should be carefully considered and monitored to ensure patient safety and effective sedation. The dose of 4 mg/kg is recommended based on the available evidence 1, and it is essential to follow proper administration and monitoring protocols to minimize the risk of adverse events.
From the FDA Drug Label
The initial dose of ketamine hydrochloride injection administered intramuscularly may range from 6.5 to 13 mg/kg. A dose of 9 to 13 mg/kg usually produces surgical anesthesia within 3 to 4 minutes following injection, with the anesthetic effect usually lasting 12 to 25 minutes. The recommended IM dose of ketamine is 6.5 to 13 mg/kg, with 9 to 13 mg/kg typically producing surgical anesthesia. 2
From the Research
Ketamine IM Dose
- The intramuscular (IM) dose of ketamine is not explicitly stated in all studies, but according to 3, dosing simulations suggest that doses of 8 mg/kg or 6 mg/kg IM, depending on age, provide adequate sedation for procedures lasting up to 20 minutes.
- The bioavailability of IM ketamine in children is estimated to be 41% 3.
- In adults, a study used a combination of midazolam and ketamine for procedural sedation and analgesia, with a mean dose of ketamine of 159 +/- 42 mg, which is approximately 2 mg/kg 4.
- Another study mentions that ketamine is most commonly administered in the dose of 0.5 mg/kg, but some patients may respond to doses as low as 0.1 mg/kg, and others may require up to 0.75 mg/kg 5.
Administration Considerations
- Ketamine can be administered through various routes, including intravenous, intramuscular, subcutaneous, oral, sublingual, transmucosal, and intranasal 5.
- The choice of route and dose may depend on the specific clinical scenario, patient population, and desired effect.
- Bolus administration is safe and effective when the drug is administered intramuscularly or subcutaneously 5.
Clinical Applications
- Ketamine is used for various clinical applications, including procedural sedation and analgesia, treatment of acute pain, and management of depression 5, 6, 7, 4.
- The efficacy and safety of ketamine have been demonstrated in various studies, but the optimal dose and administration route may vary depending on the specific clinical context.