Which parameters are final determinants of blood pressure as per the practical nurse (PN)?

The parameters that ultimately determine blood pressure are primarily related to cardiac output and peripheral resistance. Cardiac output is the amount of blood the heart pumps in a given period, influenced by heart rate and stroke volume. Both heart rate, which is how often the heart beats, and stroke volume, the amount of blood pumped with each heartbeat, play crucial roles in increasing or decreasing cardiac output.

When stroke volume increases, more blood enters the arterial system with each heartbeat, thereby increasing blood pressure. Similarly, if the heart rate rises, cardiac output also increases, leading to a potential rise in blood pressure.

While factors like blood viscosity and peripheral resistance also influence blood pressure, they are not the final determinants on their own. Cardiac output, which is derived from both heart rate and stroke volume, directly contributes to systemic vascular resistance and hence blood pressure. Thus, understanding the relationship among these components clarifies why heart rate and stroke volume are essential in determining blood pressure.