0:00
Hello, and welcome to this Henry
Stewart Lecture on Portal Hypertension.
My name is John Reinus,
an I am chief of Clinical Hepatology at
the Montefiore Medical Center in New York,
and Professor of Clinical medicine at
the Albert Einstein College of Medicine.
0:18
My thesis in this presentation is,
that portal hypertension causes multiple
regional circulatory derangements,
that result in extra and intravascular
volume overload and organ dysfunction.
It is this volume overload and
consequent organ dysfunction,
that are responsible for the clinical
signs and symptoms of portal hypertension,
in affected individuals.
0:43
The circulatory system can be compared
to the plumbing system of a large city.
At various times, different parts
of the city require a greater flow.
And similarly at different
times throughout the day,
different parts of the body require
greater circulation of blood.
The circulatory system, therefore
needs some form of regulatory control.
And this is provided by the autonomic
input from the central nervous system,
in response to signals from a variety of
receptors, including mechanoreceptors,
osmoreceptors, chemoreceptors and
thermoreceptors.
In addition, regulation is provided
by the endothelial release of
a number of short acting chemical
mediators, including nitric oxide,
carbon monoxide,
prostacyclin and endothelin.
1:36
The role of the liver is
to act as a metabolically
active filter within the circulation.
Blood enters the liver from the splanchnic
veins containing a variety of nutrients,
as well as potential toxins.
It is filtered, the nutrients
are acted on by the liver cells.
Toxins are removed, and then the blood
is returned to the central circulation.
