Gastric Dilatation-Volvulus Flashcards
What is the difference between dilatation and dilatation-volvulus?
(dilation) - distension of the stomach with fluid, food, and/or gas, making a frothy mucoid substrate
enlargement of the stomach associated with rotation on its mesenteric axis (malposition/twisting)
(underlying motility problem needs to be addressed!)
How is the gastric flora affected by gastric dilatation?
ileus stops peristalsis, resulting in bacteria from gut translocating into the peritoneal cavity
What is the most common rotation seen in GDV?
clockwise rotation of pylorus over the fundus
- between 90-360 degrees
What is gastric torsion?
rotation of the stomach less than 180 degrees clockwise or 90 degrees counterclockwise, resulting in NO complete obstruction
How is exercise thought to affect development of GDV?
pre/post prandial exercise was believed to be a risk factor
- clinical data does not support this, has not been reproduced
What are some possible dietary influences in developing GDV?
- increased volume of food fed once daily
- table food
- canned food
- fats/oils
- raised food bowl
(not all bloats are filled with food)
What breed has an increased predisposition to developing GDV?
Great Danes —> 40% die of bloat if a gastropexy was not performed
What thoracic conformation is thought to predispose to GDV development?
increased thoracic depth to width ratio —> more room for movement
What temperament predisposes to GDV development?
- high anxiety
- working/military dogs
Should all dogs getting splenectomies also get a gastropexy?
NO —> same low risk for developing GDV, already high-risk surgery that commonly results in anemia
Pathophysiology of GDV:
What are the 4 major parts of the pathophysiology of GDV?
- myocardial ischemia and cardiac arrhythmias due to decreased tissue perfusion and gastric atony (sequestration = electrolyte imbalance)
- obstructive shock correction = reperfusion injury at kidneys, heart, pancreas, stomach, and small intestine
- systemic inflammatory response syndrome (SIRS)
- disseminated intravascular coagulation (DIC)
(3 and 4 = spiraling, 10% survival rate)
What clinical signs are associated with GDV?
ACUTE ONSET:
- abdominal distension and pain with “prayer position” to take pressure off the abdomen (tympanic and painful on palpation)
- retching, vomiting
- hypersalivation
- restlessness
- lateral recumbency
- panting, heavy breathing
- coughing
- collapse
What are signs of compensatory and decompensatory shock?
COMPENSATORY = tachypnea, tachycardia, bounding pulses, prolonged CRTs
DECOMPENSATORY = MM injected (bright red), weak, laterally recumbent
What bolus and maintenance fluids are recommended for stabilization?
BOLUS = crystalloid (LRS, plasmalyte), hypertonic saline, hetastarch
MAINTENANCE = crystalloid (LRS, plasmalyte), colloids (hetastarch)
What is recommended for gastric decompression? 2 other options?
OROGRASTRIC TUBE with sedation
- nasogastric tube
- trocharization, then OG/NG tube
What are the major pros and cons to nasogastric tubes for gastric decompression?
PROS: least invasive, provide continuous drainage when there is a delay between stabilization and surgery
CON: slowest, hard to pass through gastroesophageal sphincter
What is a major pro and con to trocharization for gastric decompression?
PRO = fastest
CON = highest complication rate
How are orogastric tubes placed?
- measure from nose to xyphoid process
- apply lube and gently pass the tube
- remove air, then lavage until fluid is clear
- can tape between incisors to avoid movement of the tube
How is a nasogastric tube placed?
- proparacaine (proxymetacaine) in the nostril
- measure from nostril to xyphoid process
- apply lube and gently pass 14 Fr catheter
- suture in place
How is a gastrocentesis performed?
- clip and prep
- apply sterile gloves
- palpate for widest region
- insert 14-16 IVC
- remove stylet
What complications are associated with gastrocentesis?
- peritoneal contamination
- splenic puncture
What is seen on CBC, chemistry, and PT/aPTT in patients with GDV?
CBC - thombocytopenia if DIC
CHEM - hypokalemia
PT/aPTT - prolonged PT, normal/prolonged aPTT if DIC
What is seen on blood gas and lactate in patients with GDV?
BLOOD GAS - metabolic alkalosis due to sequestration of H+ in gastric lumen and respiratory acidosis due to hypoventilation
LACTATE - < 6.0-7.4 may indicate increased survival/decreased gastric necrosis, may not be a valuable value
When should radiographs be taken in cases of GDV? What is diagnostic?
after stabilization, don’t add stress with restraint
RL (all 3 views still important) - compartmentalization (or double bubble) where the pylorus is displaced dorsally
What are the benefits of early surgery for treating GDV?
- gastric repositioning improves blood flow
- surgery can be done before onset of arrythmias
What are the 3 objectives in the surgical management of GDV?
- reposition the stomach
- assess the severity of ischemic injury to the stomach and spleen, and resect devitalized tissue
- perform a permanent gastropexy to prevent recurrence