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abdominal structures. The author prefers a cranio-caudal method starting with the diaphragm and liver and ending with the caudal GI tract. Closure of the abdomen is performed by a continuous closure pattern of absorbable monofilament suture material.
Hemorrhagic abdominal emergencies
Pathophysiology
Hemorrhagic abdominal emergencies develop secondary to direct extension and ulceration of various malignant tumor types into the peritoneal cavity, or to rupture of
an organ enlarged from tumor invasion. Abdominal hemorrhage is most frequently associated with splenic or hepatic tumors. The most common canine splenic tumor is hemangiosarcoma. It usually affects older animals
and metastasizes in more than 50% of cases to other organs including lungs, heart, liver, kidney, omentum, and peritoneum. Mast cell tumor and malignant lymphoma occur most frequently in the spleen of cats.65 Any enlarged spleen may rupture, resulting in internal blood loss and hypovolemic shock.
Primary hepatic tumors occur in older dogs and cats but are rare. Hepatocellular carcinoma is most common and it frequently metastasizes to regional lymph nodes, lung, and peritoneum. More common than primary hepatic tumors, metastatic tumors include malignant lymphoma, pancreatic adenocarcinoma, and hemangiosarcoma. Massive hemorrhage can occur from any hepatic tumor and may require emergency laparotomy.
Clinical presentation and diagnosis
Abdominal hemorrhage results in abdominal enlargement, pale mucous membranes, lethargy, abdominal pain, tachycardia, tachypnea, and vomiting. Clinical signs vary with the severity of bleeding. In patients with exsanguinating hemorrhage, clinical signs of hypovolemic shock will predominate.
Once a diagnosis of abdominal effusion is made, little additional information is obtained by radiographic examination. The presence of fluid decreases
the value of radiography but enhances the use of ultrasonography. Radiography after removal of fluid by abdominal paracentesis may improve visualization of intra-abdominal structures and assist in diagnosis. Fluid obtained should be examined cytologically. Neoplastic cells may be identified in aspirated fluid but neoplastic disease should not be excluded on basis of negative findings. To differentiate hemorrhage from serosanguinous exudate, the packed cell volume and white blood cell counts are compared
to those of peripheral blood. The packed cell volume of serosanguinous exudates rarely exceeds 5%. An increase in packed cell volume in sequential samples may indicate continuing intraabdominal bleeding.
An Urban Experience
Alternatively, intraabdominal masses can be diagnosed by ultrasonography and guided fine needle aspiration. Non-diagnostic samples are relatively common because of sampling errors and because little material is obtained from some tumor types. Definite diagnosis may require histologic examination of a surgical biopsy specimen.
In patients with abdominal hemorrhage, clotting ability should be investigated before surgery since disturbances can be caused by the tumor. In up to 50% of dogs with splenic hemangiosarcoma there is diffuse intravascular coagulation.
Surgical therapy and aftercare
The clinical status of the patient dictates the type of treatment. An initial period of medical stabilization prior to surgical intervention may improve prognosis. Supportive therapy consists of intravenous fluid, hypertonic saline, or colloid therapy, blood transfusions, and pressure wraps. Blood transfusions are often necessary in dogs with exsanguinating abdominal hemorrhage. Autotransfusion, rather than heterologous blood transfusion, is contraindicated in tumor-induced abdominal hemorrhage, because it can spread tumor cells. Increased intraabdominal pressure by application of an abdominal pressure wrap may help control hemorrhage. Compressive abdominal and pelvic bandages are the practical alternative for seldom available antishock garments.
Emergency laparotomy is indicated if, despite fluid
and blood replacement, the animal deteriorates. The abdomen should be thoroughly explored to locate the source of bleeding and search for signs of metastases. Total splenectomy often is life-saving in hemorrhaging splenic malignancies, but a cure is rarely obtained. The prognosis for dogs with a ruptured hemangiosarcoma after splenectomy is poor, because of the tumor’s aggressive metastatic behavior. An average survival time of 2 months without and 6 months with adjuvant chemotherapy has been reported. In contrast to malignant tumors, benign splenic tumors have an excellent prognosis after surgical removal. The use of ligating-dividing staplers (LDS) allow expedient and safe surgical removal of hemorrhaging splenic neoplasms.
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