What is True about mesenteric vein thrombosisa) Peritoneal signs always presentb) Thrombobectomy is always donec) Heparin is givend) Surgery can lead to short bowel synd. and explain in detail?
Mesentric vein thrombosis is cause of mesenteric ischemia in 5 to 15% of cases (others are due to mesenteric artery emboli & thrombosis)
Mesenteric venous thrombosis is mostly associated with a hypercoagulable state (eg. Protein C, S deficiency, Antithrombosis III def., Pregnancy, Polycythemia vera, Malignancy)
Other causes are


Abdominal sepsis - pancreatitis, peritonitis, intrabdominal abscess
Protal hypertension
Trauma

Symptoms and signs

MVT may present in acute, subacute or chronic form.
The major presenting symptom is non specific abdominal pain, followed by diarrhoea and nausea and vomiting.
Occult blood in stools is seen in about half of patients.
Some patients may have lower GI bleeding. Rarely hematemesis may occur.
Peritoneal signs are present in less than half of MVT patients.

Diagnosis

Contrast enhanced CT scanning is the diagnostic study of choice.

Management

Patients with MVT are given adequate fluid resuscitation and anticoagulated with heparin.
Urgent laparotomy is indicated for patients with peritoneal findings
Nonviable bowel along with its mesentry is resected and primary anastomosis done. Viable but suspicious bowel is not resected, but a second look operation is recommended within 24 to 48 hrs.
Thrombectomy has not been proved to be successful. However, thrombectomy is indicated if a long segment of nonviable bowel is found and the angiogram or operative findings indicate complete thrombosis of SMV.
Note that MVT is usually due to thrombosis of small peripheral venous branches. Thrombosis of SMV or IMV is not common.
Patients without peritoneal sign can be managed on heparin, bowel rest and fluid resuscitation.
Heparin is replaced with oral anticoagulants in 3 to 4 days and is usually continued lifelong.
Prognosis is poor (mortality is as high as 50 %.)