there's a condition called hepatorenal syndrome it's kind of similar to someone having severe liver failure so let's say that someone has really really bad liver failure right whenever you have really bad liver failure there's a condition that can happen as a result of this called portal hypertension it's basically you know there's veins that actually come to the liver from your gi tract they're called the hepatic portal circulation right and you're supposed to be able to take blood via the hepatic portal circulation take it to the liver and then what happens is there's another big vessel here called the ivc the liver will actually clean all the blood that's coming via the hepatic portal system and then once it cleans it it puts it into the inferior vena cava to go to the right heart and then distribute to the lungs get oxygenated and so on and so forth and the patient who has hepatic portal hypertension these vessels are so fibrotic and there's so much inflammation in the liver that it reduces the portal blood flow and so the liver says oh man i'm not getting enough blood to be able to deliver to the ivc so what i'm going to do is i'm going to start releasing some chemicals i'm going to start releasing some vasodilators okay some vasodilators and the hope is that these vasodilators will counteract this actual high pressure and so if i counteract the high pressure i'll get more blood flow hopefully going through the liver and then getting filtered into the ivc but you know what actually happens as an unfortunate result you do cause some splenic vessel vasodilation but these vasodilators actually get into your systemic circulation and when they get into the systemic circulation guess what they do to multiple blood vessels in your systemic circulation it causes the systemic vessels to undergo a vasodilatory effect what happens when you vasodilate multiple systemic vessels well it's going to actually lower your blood pressure you know when your blood pressure lowers and actually kind of lowers your effective arterial blood volume when you lower your systemic blood pressure what does your body try to do in response it says hey blood pressure is low i need to try to increase the blood pressure so i can perfuse vital organs and i need to constrict the vessels to organs that are viewed as non-vital guess what the kidney unfortunately is viewed as non-vital in low blood pressure situations so when this happens this low blood pressure will actually cause intense renal artery and afferent arterial vasoconstriction and so it'll stimulate this vasoconstrictive mechanism which reduces the significant amount of blood flow to the glomerulus reducing your glomerular filtration rate and another thing that also happens is whenever you have low blood pressure you know it actually activates what's called the renin angiotensin aldosterone adh system and you know what they do what are they supposed to do they're supposed to cause a little bit of renal artery vasoconstriction that worsens that and then also you know adh and aldosterone they're supposed to reabsorb sodium and reabsorb water if you reabsorb
NO_SEGMENT_TOKEN