TIPS procedure:
Effect on kidneys, history and more
Robert Fontana, MD (internal medicine), University of Michigan,
What is the effect of low blood pressure in a patient with Hep C who is waiting
for a liver transplant?
1. TIPS is an acronym for Transjugular Intrahepatic Portosystemic Shunt. This
is a procedure performed by angiographers (vascular radiologists) at many major
medical centers throughout the country for patients with various complications
from their advanced liver disease. Initial work with the placement of TIPS devices
in humans was first reported in 1982 by Colapinto but the more modern use of
expandable metal mesh stents with significantly improved results was not reported
till 1990 by Richter. Since 1990 refinements in technique and a growing experience
with the method have made TIPS widely available in many major medical centers,
particularly in liver transplant centers.
Patients with cirrhosis develop high pressures in the main blood vessel that
supplies the liver called the portal vein due to the increase resistance to
blood flow in the diseased and scarred liver. A TIPS involves the creation of
a tissue tract from the low pressure venous system that drains the liver to
the high pressure venous system that feeds the liver in cirrhosis. The tract
is made by inserting a catheter through a large blood vessel in the neck which
communicates with the blood vessels draining the liver. Under X-RAY guidance,
doctors are then able to establish within the substance of the liver an artificial
tract or shunt to directly drain the portal vein into the general circulation.
This is done via the use of several inflatable balloons followed by the careful
insertion of an expandable, wire mesh stent. Doctors insert TIPS devices in
patients with liver disease who have serious and life threatening complications
such as the prescence of hemmorhage from the stomach or esophagus, problematic
fluid accumulation in the abdomen, and also for a form of kidney failure that
arises in some patients with advanced liver failure. In addition to sucessfully
decompressing the portal venous system in over 95% of cases, blood flow to the
kidneys frequently improves. The increased blood flow to the kidneys will not
injure them and in fact can lead to an overall improvement in kidney function
in some patients with cirrhosis.
A TIPS device is most commonly placed in a patient with chronic liver disease
resulting from cirrhosis or scarring of the liver. TIPS were originally employed
in patients as a "bridge" to liver transplantation. Nowadays, TIPS are being
placed in some centers for non-transplant patients as well to treat life-threatening
complications of cirrhosis. It should be kept in mind that a TIPS does not improve
the overall functioning of the diseased liver and really only treats the complications
of advanced liver disease. Therefore, the placement of a TIPS device is not
a permanent soloution for a patient with advanced liver disease. Many such patients
have gone on to successful transplantation without any complications related
to the placement of the TIPS device. During the transplant surgery, the TIPS
device is removed in total along with the diseased liver.
2. Many patients with cirrhosis or scarring of the liver develop abnormalities
in their cardiovascular system as a result of their liver disease. All diseases
that result in cirrhosis can lead to these cardiovascular changes but they occur
more frequently in patients with more advanced disease. It is believed that
substances circulating in the blood that are normally cleared by a healthy liver
can cause a generalized dilatation of the blood vessels throughout the body
(except in the kidney where they are intensely constricted) . The generalized
vasodilatation then results in a low blood pressure. Most patients with this
form of low blood pressure are asymptomatic because of its very gradual onset
and because of a compensatory increased blood flow from the heart. There is
no specific treatment for the development of low blood pressure in patients
with cirrhosis other than general, supportive care. The blood pressure will
normalize after removal of the diseased liver and transplantation of a healthy
liver.
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