## **Core Concept**
Intra-arterial injection of thiopentone is a serious complication that can lead to severe arterial spasm, inflammation, and potentially gangrene. Thiopentone is a barbiturate that is highly soluble in blood but can cause significant local tissue damage if accidentally injected into an artery.

## **Why the Correct Answer is Right**
The correct answer, ., implies that one of the statements provided is not true regarding the consequences or management of intra-arterial thiopentone injection. Typically, intra-arterial injection of thiopentone can lead to severe pain, arterial spasm, and potential necrosis of the affected limb. Management involves immediate discontinuation of the injection, administration of vasodilators, and potentially surgical intervention.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Typically, intra-arterial thiopentone injection can cause severe pain, which is a true statement. Therefore, this option is incorrect if it suggests that pain is not associated with intra-arterial thiopentone injection.
- **Option B:** Inflammation and arterial spasm are known complications, making any statement denying these consequences incorrect.
- **Option C:** Gangrene is a potential complication of intra-arterial thiopentone injection due to prolonged ischemia from arterial spasm, making any statement that excludes this risk incorrect.
- **Option D:** (Correct Answer) This option would represent a statement that is not true regarding intra-arterial thiopentone injection.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that intra-arterial injection of thiopentone can lead to severe limb ischemia and potential gangrene. Immediate action, including the use of vasodilators like papaverine or phentolamine, is crucial to prevent long-term damage.

## **Correct Answer: D.**