Dose of ketamine by IM route is (in mg/kg) –
**Question:** Dose of ketamine by IM route is (in mg/kg) –
A. 5
B. 7
C. 10
D. 15
**Core Concept:**
Ketamine is a dissociative anesthetic agent with both central nervous system and cardiovascular effects. It is commonly used for preoperative sedation, procedural sedation, and short-term anesthesia. Ketamine is administered primarily by intravenous (IV) route, but it can also be given intramuscularly (IM) in certain clinical situations.
**Why the Correct Answer is Right:**
The correct answer is **D. 15 mg/kg**. Ketamine is a highly protein-bound drug, which means that only a small portion (~10%) is unbound and available for binding to receptors. Intramuscular administration of ketamine results in slower absorption and distribution compared to intravenous administration. Consequently, the dose should be adjusted to ensure adequate anesthesia and sedation.
**Why Each Wrong Option is Incorrect:**
A. 5 mg/kg: This dose is too low for adequate sedation and anesthesia, especially considering the slower absorption and distribution with IM administration.
B. 7 mg/kg: Although higher than Option A, this dose may still be insufficient due to the reduced bioavailability of ketamine when administered IM.
C. 10 mg/kg: This dose is excessively high, potentially causing side effects such as hypertension, tachycardia, and hallucinations.
**Why Each Wrong Option is Incorrect:**
A. 5 mg/kg: This dose is too low for adequate sedation and anesthesia, especially considering the slower absorption and distribution with IM administration.
B. 7 mg/kg: Although higher than Option A, this dose may still be insufficient due to the reduced bioavailability of ketamine when administered IM.
C. 10 mg/kg: This dose is excessively high, potentially causing side effects such as hypertension, tachycardia, and hallucinations.
**Clinical Pearl:**
When administering ketamine for sedation or anesthesia, it is crucial to consider the route of administration and the patient's weight. The optimal dose should be tailored to the patient's body weight, ensuring adequate sedation and minimizing potential side effects. In this case, a dose of **15 mg/kg** is appropriate for IM ketamine administration, considering the reduced bioavailability and slower absorption of ketamine when administered IM.
**Core Concept:**
Ketamine is a potent anesthetic and sedative agent that acts as a N-methyl-D-aspartate (NMDA) receptor antagonist. It suppresses the central nervous system and produces dissociative effects, making it useful for procedural sedation and anesthesia.
**Why Each Wrong Option is Incorrect:**
A. 5 mg/kg: This dose is too low, providing inadequate sedation and anesthesia, especially considering the slower absorption and distribution of ketamine when administered IM.
B. 7 mg/kg: Although higher than Option A, this dose may still be insufficient due to the reduced bio