Triggers of portal vein thrombosis.
Slowed portal blood flow, structural changes in the liver, portal vein endothelial injury, plasma fibrinogen FIB, liver transplantation, diabetes, braking, oral contraceptives, history of smoking, tumors, surgery, etc. Fang Tianling, Department of General Surgery, The First Hospital of Guangzhou Medical University
Portal vein thrombosis after surgery.
6-10% of patients already have thrombosis in the portal vein before surgery (?) The patients with portal vein thrombosis are: the diameter of portal vein/splenic vein, size of spleen, postoperative portal vein flow rate, pre- and postoperative portal vein pressure, postoperative complications, coagulation function (platelets) after splenectomy, mechanical damage to blood vessels by surgery, blind end of splenic vein, coagulant use, volume deficiency, abdominal inflammation or infection.
Morbidity characteristics.
High incidence of 22%-39%, acute onset (1-3 weeks postoperatively, as early as 3 days postoperatively), often lack of clinical specificity, insidious or even asymptomatic onset easily overlooked and missed, slow chronic thrombosis with collateral angiogenesis, individual empirical treatment (lack of guideline guidance).
Typing.
I. Thrombosis limited to intrahepatic portal branches.
II. Restricted to the main portal vein.
III. Restricted to the portal vein trunk and portal vein branches.
IV. Limited to the superior mesenteric vein and/or splenic vein.
V. Restricted to the main portal vein, superior mesenteric vein and/or splenic vein.
VI. Involvement of portal vein trunk, branches, superior mesenteric vein, and/or splenic vein
Yerdel classification.
Grade I: less than 50% of the portal vein lumen, limited without extension to the superior mesenteric vein.
Grade II: 50 to 100% portal vein obstruction, with or without extension into the superior mesenteric vein.
Grade III: complete obstruction of the portal vein and proximal superior mesenteric vein, while the distal superior mesenteric vein is still patent.
Grade IV: complete obstruction of the portal, proximal and distal superior mesenteric veins.
Monitoring: signs and symptoms (abdominal pain, diarrhea, fever), D-dimer, FIB, leukocytes, ascites, ultrasound/CT, liver function
Prevention: reduction of surgical risk, protection from spontaneous shunts, low molecular heparin, enteral aspirin (50 mg qd orally), warfarin. Can prevention reduce portal vein thrombosis?
Treatment goals: eliminate thrombus or stop further spread in acute phase, improve symptoms; “recanalization” in chronic phase – restore portal blood flow
Individualized treatment.
Mild disease – no special treatment, volume expansion treatment, close observation.
If platelets > 800×109/L or fibrinogen Fbg > 4.0g/L, thrombolytic and anticoagulant treatment should be carried out for those who are diagnosed with grade II or above or grade I with severe clinical symptoms. Thrombolysis was performed by peripheral intravenous administration of urokinase 200,000-400,000 units/d , or low-molecular dextrose 250-500 mL 2 times/d for 3-5 d.
Heparinization and warfarin maintenance for 2 months
International normalized ratio (INR ) at 2-3 , PT 1.5-2.5 times.
Percutaneous transhepatic therapy (TIPS), indirect method (superior mesenteric artery route), thrombolysis
Outcome.
Portal vein cavernous degeneration.
Aggressive portal vein dissection and embolization if thrombolytic anticoagulation is ineffective and intestinal necrosis is suspected.
If intestinal necrosis has occurred, intestinal resection is performed.