Preoperative Testing And Preparation

In the elective or reasonably stable patient, preoperative testing is desirable for planning the approach to the shunt and alerting to the risk of preventable complications. Keep in mind that patients requiring emergency TIPS for catastrophic bleeds may not have time for any preoperative imaging at all. Imaging is focused on the evaluation of patency of the portal vein and hepatic veins and in planning approach to the more challenging patients. Doppler ultrasound is the easiest and least invasive way to do this, although CT, MRI, and angiography have all been used. CT scanning can be useful for understanding the morphology of the liver. Keep in mind that in advanced

Right hepatic vein

Right hepatic vein

Superior mesenteric vein

Fig. 5. Completed TIPS.

Superior mesenteric vein

Fig. 5. Completed TIPS.

cirrhotics, atrophy of the right lobe, hypertrophy of the left lobe, and hypertrophy of the caudate lobe are all common, and can require alteration of the plan of attack. Endoscopy is very desirable preoperatively in cases done for upper gastrointestinal bleeding. Although common, varices are not the only possible reason for upper gastrointestinal bleeding in alcoholic patients. TIPS has no beneficial effect on common nonvariceal causes of bleeding such as Mallory-Weiss tears or gastritis. Blood tests include LFTs, BUN, and Creatinine determination, PT/PTT, hemoglobin, hematocrit, and platelet count. Hydration of the patient is desirable, particularly in those with any degree of renal insufficiency. Radiographic contrast presents a special risk to those patients. Prophylactic antibiotics are generally given to patients preoperatively. Many regimens exist. Correction of coagulapathy is sometimes desirable, but fairly controversial. So many of these patients have baseline coagulopathies that many operators treat only severe coagulopathy (PT>20, plts<50,000). Meticulous technique and avoidance of capsular puncture are probably more important than medical pretreatment in coagulopathic individuals. Renoprotective drugs are a new, but promising preopera-tive treatment for patients with renal insufficiency. Mucomyst and Fenaldopam are the most promising. Paracentesis is usually not necessary, but in extreme cases ascites will degrade the fluoroscopy image or distort the liver orientation enough to require pre-operative drainage. Keep in mind that high volume paracentesis followed by TIPS creation adds up to significant hemodynamic alteration over a short period of time, and obligates careful monitoring of the state of hydration of the patients, particularly in those who also have GI bleeding.

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