**Question:** The dose of non-depolarising muscle relaxants in a neonate is

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

**Correct Answer:** C. 0.25 mg/kg

**Core Concept:** Non-depolarising muscle relaxants (NDMRs) are a class of drugs that inhibit neuromuscular transmission, leading to muscle relaxation. They are typically used during surgery or invasive procedures to facilitate intubation and maintain a stable respiratory status. Non-depolarising muscle relaxants work by blocking the interaction between the acetylcholine and its receptor at the neuromuscular junction.

**Why the Correct Answer is Right:** In neonates, the dose of NDMRs should be adjusted due to their immature neuromuscular system and higher propensity for complications, such as respiratory depression. The most appropriate dose for a neonate is 0.25 mg/kg, as it ensures effective muscle relaxation while minimizing the risk of adverse effects.

**Why Each Wrong Option is Incorrect:**

A. 0.1 mg/kg: This dose is too low, potentially resulting in inadequate muscle relaxation.

B. 0.2 mg/kg: This dose is too high for neonates and may lead to adverse effects.

D. 0.5 mg/kg: Similar to option B, this dose is too high for neonates and may cause complications.

**Clinical Pearl:**

When administering muscle relaxants to neonates, consider their immature respiratory system and potential for complications. Adjust the dose based on the child's weight and monitor vital signs closely, particularly respiratory rate and depth, to ensure safety and optimal therapeutic effect.