lunes, 25 de septiembre de 2017

Treatment of Gastric Varices

Download PDF Copy

By Jeyashree Sundaram (MBA)

Gastric varices occur in about half the total number of patients with cirrhosis. It is the most common reason for bleeding in upper gastrointestinal tract with high portal blood pressure and it usually occurs after esophageal varices.

Bleeding from gastric varices is the most serious condition which results to severe complexities, and needs to be controlled or managed by combination of treatment techniques.

The patients with cirrhosis or high portal blood pressure are highly prone to gastric variceal bleeding than the patients with splenic vein thrombosis (SVT).

The bleeding leads to heavy loss of blood, which should be compensated by blood transfusion to regulate the blood circulation and to maintain the hemoglobin level 7-8 g/dL.

This technique is a recovery approach to lower the risk of rebleeding and mortality. Gastric varices are treated by primary prophylaxis and secondary prophylaxis. The primary treatment includes drug therapy.

Primary Prophylaxis

The patients with variceal bleeding are immediately administered with prophylactic antibodies at the primitive stage to decrease fatality and infections.

The vasoactive drugs (somatostatin, terlipressin, or octreotide) are usually given to the patients with cirrhosis, which is considered as a first-line therapy.

It is evidenced that the vasoactive drugs are helpful in gastric varices associated with esophageal varices; however, further research is required to give evidence for the use of vasoactive drugs specifically for gastrointestinal bleeding.

Secondary Prophylaxis

The secondary prophylactic treatment includes endoscopic therapies and radiologist procedures.

Therapeutic endoscopy

Endoscopic therapies for gastric varices bleeding are endoscopic band ligation, sclerotherapy, cyanoacrylate glues, and thrombin.

Ligation: In band ligation process, the veins that profusely bleed are ligated using rubber bands to stop the blood loss. This approach is ineffective in gastric varices compared to esophageal bleeding, and has a high rate of recurrence and rebleeding.
Sclerotherapy: The endoscopic sclerotherapy involves a salt solution called sclerosant, which when injected into the veins blocks the bleeding veins by clotting the blood. Sclerotherapy is done with combination of cyanoacrylate glues for more efficient treatment. However, this method exhibits the secondary effects such as abdominal and retrosternal pain, fever, rebleeding, difficulty in swallowing, and ulceration. This treatment is also an incompetent approach for gastric varices.
Cyanoacrylate glues: Cyanoacrylate can polymerize rapidly with blood or tissue fluids. Hence, it is used as a tissue adhesive technique for treating gastric varices. In combination with N-butyl-cyanoacrylate and isobutyl-2-cyanoacrylate, it is injected into the veins through a needle by endoscopy. The bleeding vein is cleared with ethiodized oil and then glued together. This process is repeated until the varices are completely eradicated. This technique is efficient and safe to cure gastric varices, but results in uncommon complexities such as splenic infarction, adrenal abscess, and pulmonary embolism.
Thrombin: Thrombin compound influences hemostasis by clotting the blood. This method is utilized in gastric varices treatment. The most commonly used thrombin is bovine thrombin. They readily form the aggregation of the platelets when injected into the varix and results in blood clot. This approach is very effective and does not cause any undesired effects to the patients. Also, recent studies used human thrombin to control bleeding in gastric varices and resulted in greater extent of hemostasis. They are effective, safe, and no rebleeding occurs after treatment

Radiologist procedures

The gastric varices are treated through radiologist techniques, like balloon-occluded retrograde transvenous obliteration (BRTO) and transjugular intrahepatic portosystemic shunt (TIPS).

Transjugular intrahepatic portosystemic shunt: The procedure for connecting the intrahepatic veins is called TIPS. It has been well investigated in managing esophageal varices but less studies have been done on gastric varices. In TIPS, the connection between the veins is created using stents replacement. This procedure undergoes three difficulties: durability, hepatic encephalopathy, and its effect on the liver function. The main problem is TIPS is overcome by covering the stents with silicone and expanded polytetramethylene. Although the patency of the TIPS approach is extended by using covered stents, the other two problems still persist and are yet to be addressed. In addition to these prevailing drawbacks, there are other difficulties like selection of patient, where patients with deprived liver function are not suitable for TIPS.
Balloon-occluded retrograde transvenous obliteration: BRTO is used for treating gastric varices. A balloon catheter is inserted into the vein. The gastric varices is distinguished and drained through venography. Then the vein is embolized and a sclerosant is flushed to remove all varices. It is a successful and widely accepted treatment. It is used as either primary or secondary prophylaxis. This approach is found to control the bleeding rate compared with other treatments and also increases the hepatic portal blood flow, which in turn enhances the liver function. Although a more successful treatment than TIPS, it also causes some common side effects (abdominal pain, pyrexia, pleural effusion, and hemoglobinuria). The primary effect is atrial fibrillation, which results in stroke.

Reviewed by Chloe Barnett, BSc