Chapter 31 - Stomach and Duodenum Flashcards
What is the approximate capacity range of the equine stomach?
5 L to 15 L.
Where is the equine stomach primarily located?
On the left side of the abdomen with only the pyloric
region of the stomach to the right side of the midline. Its most
caudal component is the fundus, which lies adjacent to the 14th and 15th rib spaces
What is the most caudal component of the equine stomach?
The fundus.
What anatomical feature attaches the cardia to the diaphragm?
The gastrophrenic ligament.
What ligaments comprise the lesser omentum?
Hepatogastric and hepatoduodenal ligaments.
What artery provides blood supply to the equine stomach?
The celiac artery.
Where does venous drainage from the stomach occur?
Via gastric veins to the portal vein.
What marks the start of the duodenum?
The pylorus.
Which ducts open into major papila of the duodenum?
The bile and pancreatic ducts.
What is the role of the duodenocolic fold?
It attaches the duodenum to the transverse colon and proximal descending colon.
How many portions has the stomach?
The stomach can be divided
into several regions, including the 1. cardia at the opening of the
esophagus, the 2. fundus (which forms a blind sac), the 3. body, and
4. the pyloric region.
The greater omentum attaches along the
the greater curvature of the
stomach, and it blends into the gastrophrenic ligament
The greater omentum forms a blind potential space called the _________________(2w)
omental bursa
The entrance to this bursa is the _____________(2w)
entrance to this bursa is the epiploic foramen,
Where is located the epiploic foramen?
Between the caudate process of the liver
Right lobe of the pancreas
Borded dorsally caudal vena cava
Ventrally by portal vein
The lesse omentum connects the ____________(1w) and ____(1w) to the liver and consists of two ligaments the _____________ and _________________
The lesser omentum, which connects
the stomach and duodenum to the liver, consists of the hepatogastric
and hepatoduodenal ligaments
The duodenum makes a curving sharply toward the dorsal aspect of the abdomen this curve creates the ________ ___________ ___________(3w) within which the pancreas lies
The duodenum makes a curving sharply toward the dorsal aspect of the abdomen this curve creates the cranial duodenal flexure within which the pancreas lies
The bile and pancreatic dutcs open within the _____ _________ ____________(3w) and enter the duodenum at the ____ ______________ ___________(3w)
The bile and pancreatic ducts open within the cranial duodenal flexure, and enter the duodenum at the major duodenal papilla
What is the primary function of pepsinogen in the stomach?
To begin breaking down proteins.
What are the four regions of the stomach based on mucosal lining?
Nonglandular, cardiac, proper gastric, and pyloric mucosa.
What does the margo plicatus signify in the equine stomach?
The abrupt transition from stratified squamous mucosa to cardiac glandular mucosa.
What type of cells are found in the proper gastric mucosa?
Parietal cells and zymogen cells.
What hormone do G-cells secrete?
Gastrin.
Which type of cells secrete somatostatin?
D-cells.
What specialized glands are found in the proximal duodenal submucosa?
Brunner glands.
What is the role of Brunner glands?
To secrete mucin and factors that protect and repair the duodenal mucosa.
What mediates bicarbonate secretion in the duodenum?
Prostaglandin E2 (PGE2).
What is the principal secretory channel in the jejunum and ileum?
Cystic fibrosis transmembrane conductance regulator (CFTR).
What is the migrating myoelectric complex (MMC)?
A pattern of myoelectrical activity in the gastrointestinal tract.
Where is the MMC initiated in horses?
In the duodenum.
What can cause bile to appear in the stomach?
Reflux of duodenal contents during gastric emptying.
What effect does detomidine have on duodenal motility?
It markedly reduces duodenal motility.
What is transepithelial electrical resistance a measure of?
Ion permeability.
What layers comprise the stratified squamous mucosa?
Stratum corneum, stratum transitionale, stratum spinosum, and basal stratum germinativum.
Which layer primarily contributes to barrier function in the squamous mucosa?
Interepithelial tight junctions.
What is the pH at which exposure to acid significantly damages equine stratified mucosa?
pH 1.7.
What does the gastric mucosa secrete to protect against acid injury?
Mucus and bicarbonate.
What mechanism does the gastric mucosa use to expel H+ ions?
Epithelial Na+/H+ exchangers.
What region of the stomach is often referred to as a blind sac?
The fundus.
What anatomical structure is located between the caudate process of the liver and the right lobe of the pancreas?
The epiploic foramen.
What does the term “omental bursa” refer to?
A potential space formed by the greater omentum.
What significant transition occurs at the margo plicatus?
The transition from stratified squamous mucosa to cardiac glandular mucosa.
What is the clinical significance of preserving the C1 nerve during surgery?
To maintain function of the thyrohyoideus muscle.
What factors can stimulate bicarbonate secretion in the duodenum?
Factors released in response to pH changes.
What cells in the gastric mucosa amplify HCl secretion?
Enterochromaffin-like (ECL) cells.
How does the equine stomach’s size compare to its body size?
It is relatively small compared to the horse’s body size.
What anatomical feature is primarily responsible for the attachment of the greater omentum?
The greater curvature of the stomach.
What are the main protective mechanisms of the equine stomach against injury?
Stratified squamous mucosa and the secretion of mucus and bicarbonate.
Which structures enter the major duodenal papilla?
bile and pacreatic duts
Which structures enter the minor duodenal papilla?
acessory ancreatic duct
The dilated ampulla taht comes out from pylorus and goes dorsal towards the dorsal aspect of the abdomen is the cranial duodenal flexure. The cauda duodenal flexure resumes to what?
At its most dorsal aspect, the duodenum forms the caudal duodenal flexure that runs across the base of the cecum and curves caudally around the root of the mesentery to reach the left side of the abdomen.
duodenum then attaches to the transverse colon what is the name of the fold?
duodenocolic fold
Name the irrigation of the duodenum
Celiac artery that gives off–> gastrodudodenal artery and more distaly cranial mesenteric artery
There is potential collateral circulation for the duodenum?
Yes, the duodenum receives its blood supply from both the celiac artery, which gives off the gastroduodenal artery, and more distally the cranial mesenteric artery
What are the four regions of the stomach based on mucosal lining?
nonglandular stratified squamous epithelium,
cardiac epithelium,
proper gastric mucosa (glandular mucosa),
and pyloric mucosa.
What do the hormones gastrin and somatostatin promote?
they promote ehnance or reduce gastric acid secretion
The duodenal mucosa has a single layer of columnar epithelium. what is the function?
serving both secretory and absorptive functions
proximal duodenal submucosa contains specialized Brunner glands. Brunner glands are unusual in horses in that they are comprised of both ______ and_______ glands
Brunner glands are unusual in horses in that they are comprised of both mucous and serous tubuloacinar glands
These glands empty into a common duct that enters the base of the duodenal mucosal crypts, and collectively secrete 3 things
mucin
trefoil peptides
epidermal growth factor
bicarbonate to elevate the pH coming from the stomach
What senese the pH in the duodenal mucosa?
prostaglandin E2 (PGE2)
migrating myoelectric complex (MMC) consists in how many phases?
three phases of myoelectrical activity, is initiated in the horse in the duodenumthree phases of myoelectrical activity, is initiated in the horse in the duodenum
What is the baseline transepithelial resistance measurement of equine stratified squamous epithelium?
Approximately 2000 to 3000 Ohms·cm².
Which layer of the stratified squamous epithelium primarily contributes to barrier function?
Interepithelial tight junctions in the stratum corneum.
What does the gastric mucosa secrete to protect against acid injury?
Mucus and bicarbonate.
How do epithelial Na+/H+ exchangers function in the gastric mucosa?
They expel H+ ions once the cell reaches a critical pH.
What is the main mechanism of defense in stratified squamous mucosa?
Its exceptional impermeability due to high transepithelial resistance.
What portion of the stomach is most commonly involved in ulceration in horses?
The stratified squamous epithelium.
What factors can enhance the damaging effects of HCl in the equine stomach?
Bile salts and short-chain fatty acids.
What role do short-chain fatty acids play in gastric ulceration?
They damage Na+ transport activity in the stratum germinativum.
How does bile reflux impact the equine stomach?
Bile salts adhere to the squamous epithelium and can trigger damage at low pH levels.
What condition can disrupt the normal pH stratification in the equine stomach?
Periods of fasting.
Which bacteria is commonly associated with gastric ulcers in humans but not in horses?
Helicobacter pylori.
What are the key injurious factors contributing to equine gastric ulcer disease?
Gastric acid, bile, and nonsteroidal anti-inflammatory drugs (NSAIDs).
How do NSAIDs contribute to gastric ulcers?
By inhibiting prostaglandin production, which reduces mucus and bicarbonate secretion.
What dietary conditions can influence the development of gastric ulcers in horses?
High-protein diets and intermittent feeding.
What are some risk factors for the development of gastric ulcer syndrome in horses?
Stress, transportation, stall confinement, racing, and management changes.
What effect does intensive training have on equine gastric health?
It can induce squamous epithelial ulceration.
How does the route of NSAID administration affect the development of ulcers?
The route (oral or parenteral) has little influence on ulcer development.
What is a significant consequence of gastric acid in the context of ulceration?
It plays a key role in the induction of squamous epithelial ulceration.
What happens to the gastric mucosa’s protective mechanisms in the presence of NSAIDs?
Their efficacy is reduced, leading to a higher risk of ulceration.
What is the primary mechanism for healing superficial gastric erosions?
Epithelial restitution, involving the migration of adjacent epithelial cells.
What characterizes full-thickness ulceration in the gastric mucosa?
Disruption of mucosa that penetrates the muscularis mucosae.
What role does nitric oxide (NO) play in gastric repair?
It is critical for the formation of granulation tissue and proliferation of endothelial cells.
What is granulation tissue, and why is it important for gastric healing?
It provides connective tissue elements and microvasculature necessary for mucosal reconstruction.
What growth factor is expressed by repairing epithelium to facilitate wound healing?
Epidermal growth factor (EGF).
What does the mucoid cap do in the context of gastric ulcer healing?
It retains reparative factors and maintains a neutral pH to facilitate healing.
What is the time required for adult horses to be held off feed before gastric endoscopy?
24 hours.
How long should foals up to 20 days of age be fasted before endoscopy?
3 hours.
What is a significant limitation of using endoscopy for diagnosing gastric ulcers?
It may underestimate the number and severity of ulcers, especially in the nonglandular stomach.
What is the typical imaging approach for evaluating gastric outflow obstruction in foals?
Ultrasonography, particularly imaging from the left side of the abdomen.
What is the significance of barium sulfate in radiographic studies of the equine stomach?
It allows visualization of the stomach and assessment of gastric emptying and obstruction.
What are the normal gastric emptying times for liquid-phase and solid-phase in horses?
30 minutes for liquid-phase and 90 minutes for solid-phase.
What is the technique used for scintigraphic determination of solid-phase gastric emptying?
Administration of technetium-99m sulfur colloid incorporated into egg albumin.
How does breath testing with 13C-octanoic acid assess gastric emptying?
It measures the appearance of the isotope in breath samples after ingestion.
What fasting duration was required for ponies in breath testing trials?
14 hours.
How does acetaminophen absorption correlate with gastric emptying?
It closely correlates with scintigraphic measurements, showing similar clearance rates.
What is the potential finding in the stomach during ultrasonography if gastric outflow obstruction is present?
A distended stomach with a gas-fluid interface.
What diagnostic technique can reveal complications like megaesophagus in foals?
Contrast radiography using barium sulfate.
How is double-contrast radiography performed, and what is its purpose?
It involves insufflation of air followed by barium sulfate to enhance visualization of the stomach.
What is the importance of the 12- to 18-hour fasting period before administering barium sulfate for gastric emptying tests?
It ensures complete gastric emptying and accurate assessment of gastric function.
The stomach is best imaged on left side between which rib spaces?
8-14 ICS
What are the three age categories associated with gastric ulceration in horses?
Neonates, weanling foals, and horses older than 1 year.
What is the most clinically important type of ulceration in neonates?
Ulceration of the glandular mucosa.
What are common clinical signs of gastric ulceration in neonates?
Poor appetite, colic, and diarrhea.
At what age group is ulceration frequently seen in the squamous mucosa adjacent to the margo plicatus?
Suckling and weanling foals.
What is a notable clinical sign of severe ulceration in weanling foals?
Diarrhea, along with a rough hair coat and pot-bellied appearance.
What differentiates ulceration from desquamation in foals?
Desquamation involves shedding epithelium without ulceration and is less clinically significant.
What is the recommended dosage of ranitidine for treating gastric ulcers in horses?
6.6 mg/kg orally every 8 hours or 1.5–2 mg/kg intravenously every 6–8 hours.
What dietary factors can contribute to gastric impaction?
Excessive dry, fibrous ingesta, persimmon seeds, mesquite beans, and feeds that swell, like wheat and barley.
How long did colic last in horses with gastric impaction in one reported case?
Colic duration ranged from 8 to 12 hours in some cases.
What is a typical clinical sign of gastric impaction?
Colic, which may range from acute and severe to chronic and mild.
What fasting duration is recommended before diagnosing gastric impaction via endoscopy?
A minimum of 16 hours, although some reports suggest 24 hours.
What medical treatment is commonly used for gastric impaction?
Nasogastric intubation to soften ingesta with water and frequent refluxing.
What was the success rate of enteral fluid therapy via nasogastric tube for treating gastric impaction?
Successful in 18 out of 20 horses.
What surgical technique is mentioned for treating gastric impaction?
Massage and infusion via a needle adjacent to the greater curvature of the stomach.
How is chronic gastric impaction different from acute impaction?
Chronic impaction develops slowly over weeks or months, often with minimal signs of pain.
What may abdominal radiographs or ultrasonography reveal in cases of chronic gastric impaction?
A large distended and impacted stomach.
What findings are observed postmortem in chronic gastric impaction cases?
Transmural hypertrophy of the nonglandular region and large chronic ulcers along the margo plicatus.
What specific changes in gastric contents are noted after a 24-hour starvation in chronic cases?
Fibrous ingesta that does not change after starvation.
What are common clinical signs of chronic gastric dilation?
Mild weight loss, reduced performance, bruxism, and salivation.
What type of incision was used in a surgical report for gastric impaction?
An incision parallel and caudal to the attachment of the omentum on the greater curvature of the stomach.
How was the closure of the stomach after evacuation of contents?
The stocmach was closed with double-layer inverting closure
Voss EVE 2020 Which surgical techniques were used to ligate the splenic artery and vein during the splenectomy?
A) Single ligature and electrocoagulation
B) Triple ligature with encircling ligatures and electrosurgery
C) Double ligature with absorbable sutures
D) Hemostasis using mechanical clamps only
B) Triple ligature with encircling ligatures and electrosurgery.
Voss EVE 2020 What technique was used to ensure the stomach was isolated during the partial gastrectomy?
A) Use of large Doyen bowel clamps
B) Intraoperative ultrasound guidance
C) Application of a purse-string suture
D) Laparoscopic isolation
A) Use of large Doyen bowel clamps.
Voss EVE 2020 What was identified as the cause of the granulomatous inflammation in the mare’s stomach?
A) Neoplastic disease
B) Dietary indiscretion
C) Penetrating injury to the stomach
D) Chronic infection
C) Penetrating injury to the stomach.
Bauck 2021 VS What was the primary objective of the study described in the abstract?
A) To evaluate the long-term outcomes of horses after gastric surgery
B) To compare different surgical techniques for celiotomy
C) To describe a modified celiotomy to improve access to cranial abdominal structures
D) To assess the effectiveness of herniorrhaphy in horses
C) To describe a modified celiotomy to improve access to cranial abdominal structures.
Bauck 2020 VS What type of incision was utilized in the modified celiotomy approach?
A) Vertical midline incision
B) J-incision along the paracostal arch
C) Laparoscopic incision
D) Transverse incision across the abdomen
B) J-incision along the paracostal arch
Bauck VS 2020 What was the only surgical complication reported in the case series?
A) Hemorrhage
B) Organ perforation
C) Midline incisional infections
D) Anastomotic leak
C) Midline incisional infections.
What are the two general causes of gastric rupture?
Primary (excessive ingesta) and secondary (associated with another condition).
What percentage of horses with colic surgery experienced death due to gastric rupture?
11%.
What is the most common site for gastric rupture?
Greater curvature of the stomach.
What percentage of colic cases reported gastric rupture in a separate study?
5.4%
What type of closure was used to repair a subserosal hematoma associated with a gastric perforation?
Two-layer inverting closure.
What is the survival rate for horses with gastric rupture when surgery is performed?
The condition is almost universally fatal.
What breed of horses was overrepresented in gastric rupture cases?
Draft horse breeds and Friesians.
What percentage of horses with gastric ruptures had elevated blood lactate levels?
Not specified as a percentage, but noted as significant.
What is the median time from onset of clinical signs to death for gastric neoplasia cases?
4 weeks.
What is the most common type of gastric neoplasia in horses?
Squamous cell carcinoma typically in the cardia –> cause recurrent esophageal obstruction
How many horses in one report had neoplastic cells in peritoneal or pleural fluid?
Approximately 50%.
What surgical technique can relieve pyloric stenosis in foals?
Heineke-Mikulicz technique.
What is pyloric stenosis?
Gastric outflow obstruction may be the result of pyloric stenosis, which can be caused by congenital muscular hypertrophy or development of a mass at the pylorus
What is the typical age of the foal with gastric outflow obstruction?
2-6 months old with history of enteritis and an absence of clinical signs typical of foals with gastric ulcers
How can you diagnose gastric outflow obstruction?
using endoscopy, radiography, ultrasonography, and gastric emptying tests,
What is the medical tx of gastric outflow obstruction for foals?
Medical treatment for foals includes decompression of the stomach, antiulcer medications, broad-spectrum antibiotics, prokinetics, and intravenous fluids. However, surgery is indicated if medical treatment does not reverse clinical signs within 2 to 3 days
What is the principle of Heineke-Mikulicz technique?
Surgery in which a full-thickness longitudinal incision through the pylorus was closed transversely
Figure 31-2. (A) Locations for incisions for a gastroduodenostomy to bypass a pyloric stenosis. (B) A three-tiered, hand-sutured anastomosis to complete the gastroduodenostomy. (Redrawn from Orsini JA, Donawick WJ. Surgical treatment of gastroduodenal obstruction in foals.
Figure 31-3. Partial gastrectomy (A) and gastroduodenostomy (B) to relieve pyloric obstruction. Stapling instruments have been applied proximal and distal to the obstruction, allowing resection of the distal stomach. Care is taken to avoid the hepatic duct in the proximal duodenum by stapling proximal to it. The blind-ending duodenum is subsequently anastomosed to the distal stomach using an automated stapling device.
Figure 31-4. Duodenojejunostomy. The duodenojejunostomy and jejunojejunostomy are performed using an automated stapling device or a three-tiered suturing technique. The duodenojejunostomy is performed with the duodenal component proximal to the hepatic duct, and the jejunojejunostomy is performed with a segment of jejunum distal to the duodenocolic ligament.
How should be placed the jejuno in case of gastrojejunostomy?
Aligning the jejunum from left to right (oral to aboral portions of the jejunum) along a relatively avascular region of the caudal ventral aspect of the stomach for a gastrojejunostomy has been reported to substantially improve long-term outcome in 40 foals
Figure 31-5. Completed left-to-right gastrojejunostomy with jejunojejunostomy. Black arrow indicates the oral-to-aboral direction of the jejunum.
What is the prognosis for foals after surgical intervention for gastric outflow obstruction?
Fair to guarded.
What percentage of foals in one report survived after surgery for gastroduodenal obstruction?
46%.
What is the common surgical approach to treat gastric outflow obstruction?
Gastrojejunostomy.
How many layers are described for a three-layer hand-sewn anastomosis between stomach and and intestine?
Three layers (seromuscular, muscular, mucosal).
Which factors were associated with decreased long term survival in grastic outflow obstruction?
Obstructions of duodenum. adhesions to the duodenum, postoperative ileus
What key feature differentiates DPJ from small intestinal obstruction?
Elevated levels of abdominal fluid protein.
What is the reported frequency of abdominal fluid protein >2.5 mg/dL in Duodenitis-proximal jejunitis cases?
Elevated protein levels are typical, but a specific frequency is not given.
What is the typical surgical approach for duodenal obstruction?
Enterotomy to remove the obstructive mass.
What type of obstruction can occur from a congenital diaphragm in foals?
Duodenal obstruction.
What common feed-related obstruction was reported in horses?
Duodenal impaction from cracked corn.
What other conditions can cause gastric outflow obstruction besides pyloric stenosis?
Gastroduodenal ulceration or neoplasia.
What is a key clinical sign of gastric neoplasia?
Anorexia.
What is one significant prognostic indicator for survival in DPJ cases?
Level of abdominal fluid protein.
What percentage of horses with gastric rupture had a primary cause?
60% of the cases.
What is the surgical approach used for a leiomyosarcoma found in stomach of a horse?
Typically not operable, with histopathologic analysis confirming diagnosis.
What was the common treatment approach for DPJ?
Gastric decompression and analgesics.
What complication is often associated with a gastric rupture?
Septic shock.
What is the etiology of duodenitis proximal jejunitis?
The etiology of this disease is poorly understood, although several authors have proposed pathogenic bacteria such as Clostridium difficile
Duodenal obstracion has been reported with two types of mass name them
intraluminal masses or congenital structures limiting the size of the lumen
Bauck et al 2020 mention the performance of J-incision to approach the cranial abdomen in adult horse with what type of problem?
Gastric impaction
Bauck et al 2020 perfomed the J incision where?
ventral midline incision was performed 10 cm cranial to umbilicus and ending in the xiphoid cartilage and followed teh costal arch to the left where improved access to the stomach
In Bauck et al 2020 which vessel was likely encountered in the J incision?
cranial superificial epigastric artery
diagnosis
Squamous gastric ulceration complicated by gastric stenosis in a
foal EVE 2022 Witt Fig 3: Post-mortem macroscopic evaluation of a 2-month-old
foal showing a severely reduced circumferential diameter of the
stomach at the level of the margo plicatus (arrow), dividing the
stomach into a smaller (*) and larger (#) compartment (a and b).
Severe ulceration and fibrosis with granulation tissue, at the level
of the margo plicatus (c).
diagnosis and describe image
Squamous gastric ulceration complicated by gastric stenosis in a
foal EVE 2022 Witt Fig 2: Gastrointestinal contrast radiography of a 2-month-old
Warmblood foal, showing the presence of barium (*) in the
stomach and constriction in the horizontal plane in the middle of
the stomach (arrows).
Tessier et al 2019 EVJ the administration of systemic morphine (0.1mg/kg) can cause what changes in the stomach?
changes such as gastrointertinal depression, gastric distension and hyperphagia were registered
Ricord et al 2020 EVJ studied the impact of omeprazole with phenylbutazone. Did omeprazole improve the grade of ulceration? what happened to total protein []?
Omeprazole improved ulceration grade BUT incremented intestinal problems
TP [] decrease in plasma
Omeprazole is what type of molecule?
acid suppressants, such as the proton pump inhibitor, omeprazole
Bishop et al 2021 concluded that omeprazole is better or worse than sucralfate?
Omeprzole was superior to sucralfate to mitigat gastric lesion severity in healty horses exposed to NSAIDS
diagnosis hewetson EVJ 2021
Fig 9: Contrast radiography of the stomach of a foal with a pyloric outflow obstruction. (a) 5 min, (b) 60 min. Delayed gastric emptying
can be assumed if no contrast material is observed aboral to the stomach or the duodenum after 30–90 min. Images courtesy of Dr
Bonnie Barr.
diagnosis Rijkenhuizen EVE 2021
Fig 1: Laparoscopic view of the right side of the abdominal cavity showing the volvulus.
