Gastric dilatation Flashcards
GASTRIC DILATATION AND VOLVULUS (GDV) IS
AN ACUTE, LIFE-THREATENING DISORDER IN DOGS,
CHARACTERIZED BY ABNORMAL TWISTING OF THE STOMACH ON ITS MESENTERIC AXIS, WITH SUBSEQUENT GASTRIC GAS ACCUMULATION AND DISTENTION.
(can even be chronic!)
- A SERIES OF PERACUTE PaTHOPSYSIOLOGICAL CHANGES OCCUR
- ETIOPATHOGENESIS IS STILL NOT UNDERSTOOD
- HIGH MORTALITY
Risk factors for developing GDV. (10)
large & giant breeds
GDV history in family
deep narrow chest
underweight
increasing age
prev. splenomegaly or splenectomy
aerophagia, gulping food
stress
feeding once a day
small food particle size
How to lower risk of GDV development. (5)
“happy” dogs
supplementing diet with egg/fish
feeding more than once a day
large food particle size
moderate postprandial exercise
Clinical signs of GDV. (6)
restlessness
non-productive vomiting or retching
hypersalivation
abdominal distentsion
weakness
circulatory collapse
Pathophysiology of GDV. (5)
is typically clockwise rotation
can be acute or chronic
not clear if dilation or volvulus appears first
delayed gastric emptying contributes maybe
once rotation has occurred, number of local and systemic affects
Describe Gastric and splenic ischemia and necrosis. (3)
Gastric necrosis develops as result of torsion of the gastric arteries.
Necrosis of the fundus appears first.
Spleen moves and rotates with the greater curvature and can lead to splenic infarcts or necrosis.
Name the main gastric arteries espesh which are located along the lesser curvature, and which along the greater.
Celiac artery divides into splenic, hepatic and left gastric arteries around the lesser curvature. Then, gastroduodenal artery in region of lesser curvature.
Greater curvature area: left gastroepiploic artery, right gastroepiploic artery.
Diagnosis of GDV, firstly:
Normal abdo xray.
radiographs are the initial diagnostic method for GDV
you need to differentiate between plain GD and GDV
If there is volvulus, the gas filled pylorus is seen dorsal to the gas filled stomach.
typical GDV xray
whats this?
atypical GDV xray
whats this?
not GDV. pyorus is ventral, no smurf hat.
whats this?
GDV, gas filled smurf hat like pylorus dorsally is very typical.
Management of GDV, 7 steps.
- Restore perfusion (IVFT, cannula into FRONT leg)
- Gastric decompression
- Anesthesia for exlap
- Gastric derotation and decompression
- Resection of non-viable tissue
- Gastropexy
- Post-op care
Decompression of GDV.
Once GDV is confirmed, gastric decompression should be attempted.
Main 2 methods: orogastric intubation (stomach tube) and trocharization via flank.
Describe orogastric intubation. (5)
Dog sternal (and anesthetized & intubated).
Large gauge stomach tube lubed and measured.
Place tube into esophagus SLOWLY.
If you cannot advance the tube into the stomach, trocharization should be performed. Do not try to force the stomach tube!
Describe trocharization. (3)
Clip area, prepare surgically over dorsal abdo wall in area of palpable gaseous distention.
Use 14-16 gauge catheter.
Once flow of gas stops (liquid may leak out at that point), catheter should be removed.
Lactate and GDV.
Lactate is a marker of hypoperfusion and anaerobic cellular metabolism. Its a prognostic tool for GDV cases.
LAC <4 mmol/L = 99% survival
LAC >6.4 mmol/L = 23% survival
Regardless of the LAC, surgery is always recommended.
Operative techniques that you must perform in GDV. (4)
Decompression and repositioning of stomach.
Assessment of gastric and splenic viability.
Resection of devitalized tissue.
Gastropexy.
Describe respositioning of the stomach. (4)
Decompression has been attempted before exlap (via stomach tube or trochar).
Can be repeated after abdo is opened (needle into stomach wall).
Pay attention to the position of the omentum before doing anything.
In most cases, the stomach can be repositioned while surgeon stand on right side. Manually manipulate it into the anatomically correct position.
Further decompressiono and lavage can be performed if needed.
How can the omentum tell you which way the volvulus is?
If omentum is overlaid on the stomach, the volvulus is clockwise. In this case, find the pylorus on the left side where it shouldn’t be, pull on it while pushing on the fundus - this flips the stomach.
If it is not over the stomach, the volvulus is most likely anti-clockwise. To reposition, you reach your hand underneath (dorsal of animal).
Describe assessing gastric viability. (4)
Once the stomach is decompressed and repositioned, assess the gastric wall (serosa).
The greater curvature, between fundus and body, is the most common site for necrosis.
Monitor/assess the gastric serosa for 5-10 min. Do the gastropexy while you wait. Then reassess the color of the tissue.
The gastric wall should be palpated and the gastric vessels should be palpated for pulse.
Severe necrosis -> euthanasia.
Describe gastric resection. (3)
Areas of ischemia or necrosis are txed with partial gastrectomy and primary closure.
Main 3 techniques include:
open resection (self-explanatory),
stapled resection,
gastric invagination (fold in and stomach “eats” necrosed tissues)
Healthy stomach wall should be sutured with 2-0, 3-0 suture.
Nick recommends regular gastectomy over invagination technique.
Describe splenectomy & GDV. (3)
The spleen is closely associated with the greater curvature of the stomach, as a result, splenic torsion is common.
After resposition of the stomach, assess the spleen for good perfusion. Give it 5-10 min (do gastropexy while you wait).
If spleen is black, it indicates infarction. In case of changes in it, remove it.
What is that white-yellow stuff on what organ.
Splenic siderotic nodules or plaques are benign golden brown or black patches that are frequently seen on the surface of the spleen.
They result from focal accumulations of stored iron (hemosiderosis) derived from erythrophagocytosis and subsequent hemoglobin breakdown.
Not a reason to remove the spleen, seen in some animals.
Describe gastropexy. (4)
Gastropexy is the creation of a permanent adhesion between the stomach, at the level off the pyloric antrum, and the adjacent right body wall.
Numerous technique for gastropexy: incisional, belt-loop, circumcostal, ventral incision/incorporating, stapled, tube and laparoscopic.
For successful adhesion formation, the muscular layers of the body wall and the stomach should be joined.
Achieving an anatomically correct gastroepxy is important to prevent potential re-torsion or complications.
