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CHAPTER 30: Interventional Radiology 223

If there is megacava (IVC diameter >3 cm), bilateral iliac filters may be TIPS procedures done for variceal bleeding are done semiurgently in
placed. The Bird’s nest is another option for vena cava from 3 cm to patients already admitted to the ICU.
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4 cm in diameter but this device is not retrievable. 57 Development of varices is common in patients with portal hyperten-
■ IMMEDIATE POSTPROCEDURAL CARE sion and present in 30% to 70% of cirrhotics. Esophageal varices form
at a yearly rate of 5% to 8% in patients with cirrhosis but only 1% to 2%
The patient should be kept at bed rest with close observation of the are large enough to be at risk for bleeding. 62,63 Variceal bleeding from
puncture site for 4 hours if coagulation status is normal. For patient with portal hypertension is usually manifest as upper GI bleeding, although
a femoral vein puncture, the ipsilateral leg should be kept straight for occasionally, bleeding may occur distal to the ligament of Treitz. Variceal
4 hours, as bending at the hip can precipitate bleeding. If the puncture is bleeding is primarily managed pharmacologically and endoscopically
made in an anticoagulated patient, a temporary catheter may be placed with sclerotherapy and/or banding. However, endoscopic treatment is
at the puncture site to prevent bleeding. If there is oozing from the not always successful, and recurrent bleeding occurs in about 30% to
puncture site, a purse-string suture should be considered. If indicated, 50% of patients. Often, patients with refractory bleeding are then treated
heparin can be restarted immediately after local hemostasis is obtained. with TIPS creation. Similarly, portal hypertension–induced ascites or
Continued heparin therapy can be helpful to prevent extension of hydrothorax is managed medically and (if needed) with paracentesis/
thrombus in the legs or pelvis. thoracentesis. If ascites or hydrothorax is resistant to medical therapy,
■ RESULTS AND COMPLICATIONS or electrolyte imbalances, other types of therapy such as TIPS should be
or when conservative therapy results in the development of renal failure
The rate of breakthrough PE with indwelling filters varies with each par- considered.
Surgical creation of a shunt from the high-pressure portal system to
ticular filter design but ranges from 0.5% to 3% for permanent filters. 48,58 the central venous circulation allowing for decompression of the portal
For the newer retrievable filters, the rate ranges from 0.7% to 4%. system, was performed more frequently in the past but associated with
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However, these numbers should be interpreted with caution as it is significant morbidity and mortality, especially when performed emer-
difficult to compare one type of filter to another and most published gently. TIPS is performed percutaneously and it functions like a surgi-
reports are retrospective with variable study designs. Complications of cally created portosystemic shunt, but the TIPS procedure is associated
IVC filter placement include caval thrombosis, filter migration, DVT, with reduced morbidity and mortality.
and penetration of IVC to adjacent structures. Caval thrombosis var- Indications for TIPS that have been validated in controlled trials
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ies with filter design and ranges from 2% to 9%. In some patients, caval are (1) secondary prevention of variceal bleeding and (2) refractory
thrombosis should not be considered a “complication” of the filter but cirrhotic ascites. Other indications include acute variceal hemorrhage
rather, the filter functioning properly and preventing massive thrombus refractory to endoscopic treatment, portal hypertensive gastropathy,
from the legs from migrating to the lungs. For the retrievable filters, the bleeding gastric varices, gastric antral vascular ectasia, refractory hepatic
most common complications are filter migration and strut perforation hydrothorax, hepatorenal syndrome, Budd-Chiari syndrome, hepato-
of the IVC wall. In our experience, migration appears to be higher pulmonary syndrome, and venoocclusive disease. 64
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with some retrievable filter designs compared to others and compared Preprocedure evaluation of an ICU patient who might need TIPS
to permanent filters but there are no prospective comparative studies procedure should include a gastroenterologist or hepatologist in con-
confirming this observation. As stated above, retrievable filters should junction with an interventional radiologist and intensivist from the ICU.
be removed when caval filtration is no longer needed. It is impor- Although TIPS can be used in an urgent situation to control variceal
tant to recognize that as a rule of thumb, the longer a filter remains hemorrhage successfully, it must be recognized that urgency is an inde-
in vivo, the more difficult it will be to remove. The reported overall pendent predictor of early mortality and stabilizing a patient prior to
retrieval rates range from 12% to 45% with a mean indwelling time of the procedure is preferable when possible. Pre-TIPS evaluation includes
72 days. Technical success rates for retrieval are 99% at 1 month, 94% laboratory evaluation of hepatic and renal function, hepatic imag-
at 3 months, and 37% at 12 months with the most common cause of ing with Doppler US, and contrast-enhanced CT or MRI. Portal vein
retrieval failure being filter tilt and filter incorporation into IVC wall. As patency should be verified. If the portal vein is occluded, TIPS insertion
stated above, filter retrievable should be considered when the risk of PE at best, is technically very difficult and at worst, impossible.
is less than risk of having an indwelling IVC filter. 51
It is critical to objectively assess patient candidacy. In many patients,
TIPS will improve symptomatology and may be lifesaving. However,
TRANSJUGULAR INTRAHEPATIC in some, TIPS may result in fulminant liver failure, new or worsening
PORTOSYSTEMIC SHUNT encephalopathy, or premature death. In patients with variceal hemor-
rhage, pre-TIPS condition (MELD score, APACHE II score, urgent
indication) is a good indicator of the 30-day survival. Classifications have
KEY POINTS been developed in an attempt to stratify patient risk and predict survival
after TIPS. The Child-Pugh classification considers the presence and
• TIPS is a second-line therapy used to treat ascites or variceal bleed-
ing refractory to medical and endoscopic management. degree of ascites and encephalopathy, as well as the serum bilirubin
and albumin concentrations and the INR. The MELD score is based on
• Covered stents used currently have improved patency compared serum creatinine, bilirubin level, INR, and etiology of the underlying
to uncovered stents used in the past, improving the durability of liver disease. Prior to development of the MELD score the Child-Pugh
the procedure. score was used but it has been shown that the MELD score is a better
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■ INDICATIONS AND PATIENT SELECTION predictor of 3-month outcome than the Child-Pugh score and that
a low MELD risk score is associated with improved survival. MELD
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calculators are available online.
The transjugular intrahepatic portosystemic shunt (TIPS) is used to Once a TIPS is indicated, fluid resuscitation to treat ongoing bleed-
treat complications of portal hypertension, 60,61 typically variceal hemor- ing and correction of existing coagulopathies are important to achieve
rhage or ascites refractory to medical or endoscopic management. Portal and maintain throughout the periprocedural period. In patients with
hypertension is reduced by creating a shunt between the portal vein and ascites, paracentesis prior to the procedure can facilitate safe creation of
hepatic veins that enables portal venous blood to bypass the liver. Most a TIPS. In many instances, general anesthesia or at least involvement
TIPS procedures done for refractory ascites are done electively with of an anesthesiologist may be necessary to monitor and manage criti-
patients subsequently managed in the ICU after shunt insertion. Many cally ill patients with hemodynamic instability.

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