Which of the following is a cardiovascular systemic sign of local anesthetic toxicity?

• A. Arrhythmia, cardiac arrest, hypotension
• B. Metallic taste, numbness
• C. Flushing, sweating
• D. Hives, angioedema

Answer: (A)

The main idea is that local anesthetic toxicity can progress from neurological symptoms to cardiovascular collapse as the drug concentration rises. Local anesthetics block sodium channels in cardiac tissue, which disrupts conduction and depresses the heart’s ability to pump. This leads to arrhythmias, hypotension, and in severe cases cardiac arrest. So the sign described as arrhythmia, cardiac arrest, and hypotension best represents cardiovascular involvement of LAST. By contrast, metallic taste and numbness are early CNS symptoms; flushing and sweating can occur with stress or autonomic activity but are not specific cardiovascular toxicity signs; hives or angioedema suggest an allergic reaction rather than LAST.