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Gastric Dilation/Volvulus 377

Gastric Dilation/Volvulus Client Education
Sheet
VetBooks.ir Diseases and Disorders

• Splenomegaly
BASIC INFORMATION
• Clinical signs of hypovolemic shock: weak ○ Free abdominal air suggests gastric
perforation.
Definition pulses, tachycardia, pale mucous membranes, • Quick assessment tests
Rotation of the stomach on its mesenteric axis prolonged capillary refill time, dyspnea ○ Packed cell volume/total solids (PCV/TS):
is associated with gastric distention and well often increased due to hypovolemia
recognized in large- and giant-breed dogs. Etiology and Pathophysiology ○ Serum electrolyte and glucose concentra-
• In most cases, the pylorus moves ventrally tions: +/− hypokalemia and hypoglycemia
Synonyms and from right to left; the rotation may be ○ Acid-base analysis: metabolic acidosis due
Bloat, gastric torsion, GDV 90°-360°. to lactic acidosis is frequently present.
• Gastric dilation occurs secondary to failure of • Coagulation panel and platelet count:
Epidemiology eructation and pyloric outflow obstruction. thrombocytopenia, increased prothrombin
SPECIES, AGE, SEX Dilation can occur before or after gastric time/activated partial thromboplastin time/
Risk of gastric dilation/volvulus (GDV) increases rotation. fibrinogen concentration and/or fibrin deg-
with age; rarely reported in small dogs or cats • The distended stomach results in caudal vena radation product concentration associated
cava and portal vein compression, causing with disseminated intravascular coagulation
GENETICS, BREED PREDISPOSITION decreased venous return to the heart. (DIC)
• Large- and giant-breed dogs • Decreased venous return results in decreased • Electrocardiogram (ECG [p. 1094]): ven-
• Great Dane, German shepherd, Weimaraner, cardiac output, decreased arterial blood tricular arrhythmias are common.
Saint Bernard, Gordon setter, Irish setter, pressure, and myocardial ischemia.
Doberman pinscher, Old English sheepdog, • Myocardial ischemia causes cardiac Advanced or Confirmatory Testing
and standard poodle are overrepresented. arrhythmias. • Definitive diagnosis confirmed at surgery
• Having a first-degree relative with GDV • In the case of volvulus, increased intralu- • Plasma lactate concentration: may assist in
confers an increased risk. minal gastric pressure, portal hypertension, determining prognosis. In dogs, a cutoff of
and avulsion of the short gastric vessels 7.4 mmol/L at admission correctly predicts
RISK FACTORS compromise blood flow to the gastric wall. presence or absence of gastric necrosis with
Increased risk may be associated with Gastric necrosis and perforation can result. 82% accuracy and survival versus euthanasia/
• Narrow and deep thoracic cavity Breakdown of gastrointestinal mucosa allows death with 88% accuracy.
• Stress bacterial translocation.
• Fearful temperament • Portal vein compression/hypertension TREATMENT
• Being underweight causes sequestration of splanchnic blood
• Nutritional risk factors include once-daily and decreased ability to clear gram-negative Treatment Overview
feeding, feeding dry dog food, rapid ingestion endotoxins. The initial therapeutic goal is to manage
of food, consumption of large volumes of • Endotoxemia further potentiates hypotension hypovolemia with intravenous (IV) fluids and to
food, and eating from a raised feeding bowl. and decreased cardiac output. decompress the stomach to re-establish systemic
• Conflicting reports regarding risk associated • Pressure on the diaphragm, decreased lung and gastric perfusion. Definitive treatment
with prior splenectomy perfusion, and decreased lung compliance involves surgery to correct the position of the
cause respiratory dysfunction and exacerbate stomach, remove devitalized tissue, and perform
GEOGRAPHY AND SEASONALITY tissue hypoxia. a gastropexy to prevent recurrence.
Possible increased incidence in the months of
November, December, and January (United DIAGNOSIS Acute General Treatment
States) • Place large-bore IV catheters in both cephalic
Diagnostic Overview veins or cephalic and jugular veins, and
ASSOCIATED DISORDERS GDV should be suspected in large- or giant- infuse isotonic crystalloids at an initial dose
• Inflammatory bowel disease breed dogs presenting with an acute history of of 20 mL/kg as fast as possible to effect
• Gastric foreign body or mass a distended or painful abdomen, often with (lowered heart rate, raised blood pressure).
• Hypovolemic shock preceding or concurrent attempts at vomit- Additional doses can be given if needed.
• Cardiac arrhythmias ing. Physical exam usually reveals a tympanic Colloids can be administered in combination
abdomen and often signs of shock. Treatment with crystalloids at 5-20 mL/kg over 15-30
Clinical Presentation for shock is initiated before confirming the minutes. For severe shock, hypertonic saline
HISTORY, CHIEF COMPLAINT diagnosis with radiography. can be administered at 4 mL/kg over 10-15
• Acute onset abdominal distention minutes, followed by crystalloids (p. 911).
• Abdominal pain Differential Diagnosis • Administer parenteral prophylactic antibiotics
• Restlessness • Gastric bloat associated with overeating (e.g., cefoxitin 30 mg/kg IV perioperatively,
• Ptyalism • Mesenteric volvulus then q 6h).
• Retching or vomiting (nonproductive with • Splenic torsion • Decompress the stomach by orogastric
volvulus) • Diaphragmatic hernia with stomach herniation intubation (p. 1117).
• Acute collapse • If orogastric intubation is not possible and
Initial Database patient has visible abdominal distention
PHYSICAL EXAM FINDINGS • Abdominal radiographs with a radiographically confirmed GDV,
• Abdominal distention and tympany ○ Right lateral view is preferred. perform percutaneous trocarization of the
○ Simultaneous auscultation and percussion ○ Shows gas-filled pylorus cranial and dorsal stomach:
of the abdomen may reveal a tympanic to the fundus (Popeye sign, C sign, or ○ Aseptically clip and prepare an area on
sound, indicating a taut, gas-filled stomach. double bubble) the dorsolateral abdomen, just caudal to

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