National Dental Examining Board of Canada (NDEB) Practice Exam 2025 – The Comprehensive All-in-One Guide to Exam Success!

Cardiovascular collapse can occur when individuals inadvertently receive a large dose of local anesthetic. This can cause severe systemic toxicity, resulting in a decrease in heart rate, blood pressure, and cardiac output. This is known as myocardial depression, which can lead to cardiovascular collapse. Option B, ventricular fibrillation, is incorrect as it refers to a specific type of arrhythmia that can occur in response to local anesthetic toxicity, rather than being the cause of cardiovascular collapse. Option C, arterial blockage, is incorrect as it does not specifically address the mechanism of cardiovascular collapse in response to high doses of local anesthetic. Option D, respiratory arrest, is also incorrect as it is not a direct cause of cardiovascular collapse, although it can contribute to it in certain cases.