By Col. Stefanos Kladakis, Veterinary Surgeon

GENERAL

Gastric dilatation and volvulus (GDV) is an acute life-threatening disorder in dogscharacterized by abnormal twisting of the stomach on its mesenteric axis, withsubsequent gastric gas accumulation and distension. Dogs of any breed can developGDV with deep chested and large breeds being the most at risk. Immediatetreatment goals include correction of hypovolemia and gastric decompression tomake the patient as stable as possible for anaesthesia. Surgery is advised to addressthe disorder.

DIAGNOSIS

Patients suffering from GDV may have a history of a progressively distending andtympanic abdomen, or the dog may be found recumbent and depressed with adistended abdomen. Non-productive retching, hypersalivation, and restlessness arecommon.Clinical signs associated with shock (weak peripheral pulses, tachycardia, prolongedCRT, pale mucous membranes, dyspnea) may be present.Regarding laboratory findings, CBC is seldom informative unless DIC causesthrombocytopenia. Potassium concentrations vary, but hypokalemia is morecommon. Vascular stasis may cause increased lactic acid and metabolic acidosis.Plasma lactate should be measured at presentation and 12 hours after resuscitationwith fluids administration. A decrease in plasma lactate concentrations ≥ 50% within12 hours may be a good indicator for survival.

DIAGNOSTIC IMAGING

Radiographs can help to differentiate simple dilatation from dilatation plus volvulus.Affected animals should be decompressed before radiographs are taken. Right lateraland dorsoventral radiographic views are preferred. Presence of free air in theabdominal cavity suggests gastric rupture and air within the wall of the stomachindicates necrosis, both of which are indications for an emergency surgery.

MEDICAL MANAGEMENT

Stabilizing the patient’s condition is the initial objective. So, fluid resuscitation andadministration of bactericidal antimicrobials are mandatory for initial managementof GDV patients.Crystalloids are administered iv and patients are re-evaluated every 20 minutes. Ifhypokalemia is present potassium supplementation of iv fluids is advocated.Gastric decompression should be performed while shock therapy is initiated. Thestomach may be decompressed percutaneously with several large-bore IV cathetersor (preferably) a stomach tube may be used. Stomach tube passing does not excludethough presence of volvulus.Please refer to emergency and critical care papers for additional informationregarding medical management of GDV patients.

SURGICAL TREATMENT

The animal should be given IV fluids and antibiotics before surgery. Numerousanesthetic protocols have been described for GDV cases. Patients are placed in dorsalrecumbency, and their abdomen is prepared for a midline abdominal incision (prepthe area from mid-thorax to the pubis).

Which are the goals of surgical treatment? What we should perform?

• Gastric decompression. In case of volvulus the abnormally positioned stomachshould be repositioned.

• Abdominal exploratory paying attention to stomach and spleen. Any necrotictissue present should be removed.

• Gastropexy.

Step 1: Abdominal exploratory and gastric decompression

At the operating room the surgeon should reposition the abnormally positionedstomach and critically evaluate the abdominal viscera. Upon entering the abdominalcavity of a dog with GDV, the first structure noted is the greater omentum, whichusually covers the dilated stomach. Typically, a clockwise volvulus has occurred.Therefore, the gastric fundus can be pushed dorsally while pulling the pylorusventrally and toward the right. Surgeons must always confirm that the stomach hasreturned to its original position in the abdominal cavity and allow time for organs toreperfuse after that. The greater curvature and fundus of the stomach are examinedfor areas of necrosis.

Factors that can be used to assess the viability of the stomach wall afterdecompression and repositioning include color, pulse in gastric arteries, peristalsisand stomach wall texture. Viability of spleen should also be assessed. If, any necrotictissue is identified partial gastrectomy or splenectomy should be performed.If necrosis is present, the prognosis is unfavourable to grave.

Step 2: Gastropexy

A right-sided incisional (or modified incisional) or belt-loop gastropexy is performedto create a permanent adhesion between the pyloric antrum and the adjacent rightbody wall. This technique is based on the construction of a seromuscular antral flapattached to a scarified segment of transversus abdominis muscle. A 4-6 cm incisionis made in the antral portion of the stomach. The bleeding surface of the antrum isbrought to the right body wall. With the stomach in a normal position, the bleedingantral surface is touched to the peritoneal wall to create a blood mark on theperitoneum. This is the location of the gastropexy. The peritoneum and transversusabdominis muscle are incised creating a mirror image defect of the stomach flap.The stomach incisional defect is sutured to the abdominal wall incisional defect witha simple continuous appositional suture pattern with a synthetic absorbablemonofilament suture material like polydioxanone or polyglyconate.

POSTOPERATIVE MANAGEMENT

Postoperative management is typically a continuum of care from pre- andintraoperative therapy. For analgesia, injectable opioids are recommended.Gastroprotectants and prokinetics can be administered. Antibiotic administration forsome days after surgery is often indicated based on the presumed risk for bacterialtranslocation. Usually 3-4 days of intensive monitoring and treatment is necessaryfor the successful management of GDV patients.

COMPLICATIONS

Cardiac arrhythmias, hypokalemia, gastric hypomotility, shock, gastric ulcerations ornecrosis, peritonitis and recurrence are the most common complicationsencountered.

PROGNOSIS

Animals treated surgically for GDV have an overall 10% to 28% mortality rate. Poorprognostic factors include lactate level not responding to fluid resuscitation, need forsplenectomy, gastrectomy and preoperative arrhythmias. With timely admission andsurgery, the prognosis for most patients is fair.