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46 GASTRIC DILATATION AND VOLVULUS PEER REVIEWED A rationale exists for the use of antibiotics in patients with GDV: there is the presumed risk for bacterial translocation with gastric mucosal compromise and increased mucosal permeability, as well as venous stasis and poor hepatic perfusion, likely resulting in inhibition of reticuloendothelial function. Ventricular arrhythmias are reported in up to 40% of dogs with GDV; therefore, continuous ECG should be monitored. 1 Ventricular arrhythmias that could decrease cardiac output or develop into ventricular fibrillation (specifically, ventricular tachycardia, R-on-T phenomenon, or multiform ventricular premature contractions) should be treated with IV lidocaine boluses initially, followed by a constant rate infusion if the bolus is successful in converting the rhythm to a sinus rhythm. If lidocaine is not successful in converting the rhythm, procainamide or sotalol can be administered ( Box 2 ). Other therapeutic modalities to consider include oxygen supplementation, especially in patients with signs of poor perfusion; fresh frozen plasma transfusion if indicated based on prolonged coagulation times or evidence of disseminated intravascular coagulation; or dextrose supplementation if a patient is hypoglycemic from septic shock. There may be a role for pharmacologic methods to reduce reperfusion injury, but consistent data on their efficacy are lacking. 16 When possible, complete fluid resuscitation (characterized by normalization of perfusion measures listed in Box 3 ) should be attempted before surgery because increased time from presentation to surgery has been associated with a lower mortality rate. 17 Survival is positively affected by the time spent adequately stabilizing the patient; however, surgery should always be performed in a timely manner to limit the duration of splenic and gastric ischemia. General anesthetic protocols vary depending on patient status; anesthetic agents that are arrhythmic or cardiac depressants should be avoided. Typical premedications consist of a pure mu agonist opioid and a benzodiazepine, induction agents (such as etomidate or propofol), and an inhalant to maintain anesthesia. Monitoring of response to treatment and adjusting fluid therapy accordingly are still crucial during the intraoperative period. SURGERY Surgery has 3 goals: 1. Reposition the abnormally positioned stomach. Typically, a clockwise volvulus has occurred; therefore, the fundus can be pushed dorsally while pulling the pylorus ventrally and toward the right. 2. Critically evaluate the abdominal viscera. Allow time for organs to reperfuse, and confirm correct gastric positioning. If necessary, perform partial gastric resection or splenectomy to remove necrotic tissue. 3. Perform a right-sided gastropexy to create a permanent adhesion between the pyloric antrum and the adjacent right body wall. Gastric Repositioning A ventral midline celiotomy is performed. Adequate exposure is essential and the incision should extend from xiphoid to pubis. When the surgeon first enters the abdomen, the greater omentum is usually covering the stomach and should be gently retracted. Derotation of the stomach is facilitated by decompressing the gas distention, either by the anesthetist passing an orogastric tube or by the surgeon evacuating the air with a large-gauge needle. The typical direction of volvulus is clockwise, with rotation of 180° to 270° being most common. In most cases, the stomach can be repositioned with the surgeon standing on the dog's right side to push the fundus dorsally and to the dog's left while simultaneously gently pulling the pylorus (located on the left initially) ventrally and toward the surgeon on the right. After repositioning, confirmation of normal gastric position is crucial. Although rare, a counterclockwise volvulus or a rotation through a rent in the splenic mesentery is possible, so the surgeon should always verify correct stomach positioning via careful observation and palpation of the gastroesophageal junction. Evaluation of Abdominal Viscera There is often free peritoneal blood due to avulsion of the short gastric arteries and veins when the stomach distends and rotates. Bleeding has typically Survival is positively affected by the time spent adequately stabilizing the patient; however, surgery should always be performed in a timely manner to limit the duration of splenic and gastric ischemia.