Why do our bodies maintain blood pressure but not the flow rate?

Question

This might be a silly question but i'm not not clear I'm always told that blood pressure is homeostatic parameter and can't not be changed but isn't what important is the flow rate to the organs? why not maintain flow rate Doesn't having enough blood flow to the organ already satisfy our bodies to function properly or do pressure play any role? what happens if blood flow is constant but blood pressure drop below normal there's some case when one have blood lost , pressure drop and our bodies respond by constricting artery and that results in decreased cardiac output.Isn't that worst? decrease cardiac output just to maintain blood pressure Forgive my little understanding out this I know my thought is kind of logically wrong but please help me understand. thank you

Answer 1

Blood flow = Change in pressure (pressure gradient) divided by resistance. Therefore, blood flow and pressure are directly related, meaning that when you increase the blood pressure (pressure gradient between two points) blood flow will increase if resistance remains the same. So the way to think about it is that you shouldn't try to separate the two, just know the relationship between them, which is that they are directly proportional and that blood flow is indirectly proportional to resistance. Message me and we can talk more about this topic. I'd be more than happy to help. Cheers! -Dr.B-