Radioloksabha



TRANSJUGULAR INTRAHEPATIC PORTO-SYSTEMIC SHUNT (TIPS)Percutaneously created connection within the liver between the portal and systemic circulations Placed to reduce portal pressure in patients with complications related to portal hypertensionLess invasive alternative to surgery in patients with end-stage liver disease. Mainstay of nonsurgical treatment of PHT due to cirrhosis.Highly effective as salvage therapy in high-risk patient with active variceal hemorrhage with failed endosopic scleropathy.Goal – To reduce portal vein-hepatic vein gradient to ≤12mm Hg.INDICATIONS : 1)Accepted indications -A) Acute variceal bleeding that cannot be successfully controlled with medical treatment, including sclerotherapy B) Recurrent and refractory variceal bleeding or recurrent variceal bleeding in patients who cannot tolerate conventional medical treatment, including sclerotherapy and pharmacologic therapy.2) Unproven but promising indications -A) Therapy for refractory ascites B) Portal decompression in patients with hepatic venous outflow obstruction (Budd-Chiari syndrome), hepatic hydrothorax, or hepatorenal syndrome3) Unproven uses -A) Initial therapy of acute variceal hemorrhage B) Reduction of intraoperative morbidity during liver transplantationCONTRAINDICATIONS 1) Absolute contraindications ----Right-sided heart failure with increased central venous pressure Polycystic liver disease Severe hepatic failure2) Relative Contraindications-Active intrahepatic or systemic infection Severe hepatic encephalopathy Hypervascular hepatic tumors PV thrombosis PATIENT PREPARATION : Prophylactic broad-spectrum antibioticsAppropriate resuscitation with fluid and blood products prior to the procedureConfirmation of PV patency by ---1) Doppler sonography 2) arterial portography via the splenic or superior mesenteric artery3) In the presence of reversed intrahepatic portal flow, the PV may not fill during arterial portography, than Magnetic resonance venography may have a promising role in assessing PV patency prior to TIPS If platelet counts are less than 50,000 mm3 – administration of platlet an international normalized ratio (INR) of greater than 2.0.= give FFPCommercially available sets ----Colapinto transjugular and biopsy set --16-gauge Colapinto puncture needle. Rosch-Uchida transjugular liver access set Angiodynamics TIPS set Ring transjugular intrahepatic access set APPROACH---Right internal jugular- preferred becoz it provides direct straight line needle access to liverOther- external jugular left internal jugular femoral v.Procedure – Initially, placement of 9F hemostatic sheath advanced into right atrium. Recording of atrial pressureSheath is threaded into IVC 5F diagnostic catheter passed through sheath & advanced to liver Balloon catheters introduced via the internal jugular vein can be passed down the superior and inferior vena cava into the hepatic veins(Usually right hepatic v; if blocked, than middle or left hepatic v. If all are blocked or stenosed, than creation of TRANSCAVAL INTRAHEPATIC PORTOSYSTEMIC SHUNT)WEDGED CONTRAST VENOGRAPHY– to attempt to visualize intrahepatic portal vein - Typically, a 50-mL manual injection of CO2 is given which usually demonstrates the location of the main PV, as well as that of the left and right branches. Now diagnostic catheter exchanged for COLAPINTO needle (length- 50 cm, 16 G,curved needle with 45 cm long teflon sheath).Under radiological guidance, puncture across an appropriate strip of liver tissue can be achieved into a dilated portal branch. Balloon rupture and dilatation of this tissue 'window' can then be performed with relative safety, since the surrounding liver tissue provides some degree of support to the damaged tissue. Deployment of metallic stent within the shunt tractTypes of metallic shunts-----Palmez Gianturco Wallstent Strecker Postplacement venography - pressures are measured to confirm adequate stent positioning, good flow through the TIPS, and reduction in the portosystemic gradient COMPLICATIONSRelated to the puncture site pneumothorax, vessel or tissue injury arteriovenous fistula formationPlacement of the catheter in the right atrium cardiac dysrrhythmias During the creation of the intrahepatic tractInjury to the hepatic artery or bile ductsCapsular tears result in life-threatening hemorrhage when they occur in association with a hepatic artery puncturePortal venous puncture After a newly placed TIPS New onset or worsened encephalopathyPredisposing factors -preprocedural hepatic encephalopathy Child class C cirrhosis Large diameter and degree of portosystemic gradient reduction Shunt stenosis and occlusionEarly shunt thrombosis (often within 24 h) is usually believed to be secondary to extension of the intrahepatic tract across a bile ductAnd treated with balloon dilation of the stent. The use of covered (polytetrafluoroethylene [PTFE], polyester) stents Deterioration of the patient's hemodynamic status Due to increases in cardiac output and central venous and pulmonary wedge pressures can result in acute pulmonary edema and congestive heart failure ADVANCED TIPS TECHNIQUESIf standard portal venous access fails ---to percutaneously place a transhepatic Chiba (Cook) needle, which can be used as a target under fluoroscopy to advance the Colapinto needle Alternatively, puncture of a patent umbilical vein If direct PV and right atrial pressures (measured to determine the portosystemic gradient) show a less-than-expected gradient, a competitive shunt (spontaneous splenorenal or large varices) should be excluded by advancing the catheter into the splenic or mesenteric vein and injecting bolus of contrast agent with digital imaging If competitive shunt is present then Competitive shunts can be selectively embolized with coils If no competitive shunt is found and if the gradient is less than 12 mm Hg, TIPS is not indicated CLINICAL IMAGING FOLLOW-UPpatients undergo a baseline Doppler study within 24 hours of the procedure to document functional parameters Doppler criteria for high sensitivity and specificity of shunt function Surveillance ultrasonography is recommended at 3 and 6 months after the procedure and twice yearly thereafter CAUSES FOR SHUNT FAILURE1) Technical failure due to an anatomic situation that prevents acceptable portal venous puncture2) Late stenosis and occlusion due to pseudointimal hyperplasia within the stent more commonly, intimal hyperplasia within the hepatic vein. TIPSS MalfunctionDirect signsNo flow – consistent with shunt occlusion or thrombosis.Low-velocity flow – especially at portal venous end of shunt.Change in peak shunt velocity – increase or decrease from baseline of 50cm/s.Reversal of flow in hepatic vein.Hepatopetal intrahepatic portal venous flowSecondary signs Reappearances of varices Reaccumulation of ascitesReappearance of recanalized paraumbilical vein10% risk of encephalopathyShunt stenosis in 50% cases by 6 months ----- narrowing progresses with time ................
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