How does the cardiovascular system (CVS) typically respond to overdose of local anesthetics?

In an overdose of local anesthetics, the cardiovascular system often exhibits an initial response characterized by an increase in heart rate (HR) and blood pressure (BP). This response is primarily due to the stimulation of the sympathetic nervous system. Local anesthetics can cause vasodilation, but at low levels of toxicity, they may first induce a sympathetic response, leading to an increase in myocardial contractility and heart rate.

As the overdose progresses or if toxicity becomes more severe, the cardiovascular system can become depressed, potentially leading to bradycardia and hypotension. However, during the early stages of local anesthetic overdose, the sympathetic stimulation and catecholamine release can cause these initial increases in heart rate and blood pressure before serious challenges arise.

The statement about the cardiovascular system being more sensitive than the central nervous system refers to the different ways in which local anesthetic toxicity can affect these systems, but it is in the early phase where the cardiovascular reactions typically manifest as increased HR and BP. Thus, understanding the typical physiological response to local anesthetic overdose is crucial for the effective management of such occurrences.