GI Flashcards
List and briefly explain 7 possible causes of perineal hernias in dogs
There are many proposed causes of perineal herniation in the dog. These include:
1) rectal abnormalities (rectal deviation, rectal diverticulum- likely a result of herniation but contributes to straining and further weakening of the pelvic diaphragm)
2) The effect of androgens (predominantly observed in intact males; neutering significantly decreases the chance of recurrence)
3) Gender-related anatomic differences (the female pelvic diaphragm is larger, broader and stronger than that of males)
4) Relaxin hormonal effect (affects collagen metabolism, causing relaxation and stretching of inelastic tissues. Affected dogs have higher expression of relaxin receptors within the pelvic canal)
5) Prostatic disease (Observed in 25 to 50% of dogs with perineal hernias. Possible due to prostatomegaly leading to increased abdominal pressure during urination, caudal displacement of the prostate or periprostatic cysts.
6) Testicular disease (observed in 69% of dogs with perineal hernias – cause-effect no established)
7) Neurogenic atrophy (neurogenic atrophy of the coccygeus and levator ani muscles due to nerve damage to the muscular branches of the pudendal and pelvic nerves. Possibly resulting from a degenerative neurogenic myopathy. Tenezmus from prostatic enlargement has been suggested as the cause of traction applied to the sacral plexus nerves.
A patient presents with a large perineal hernia. He is also unable to urinate. You perform a paracentesis and obtain fluid similar to urine, suggesting urinary bladder retroflexion into the hernia. How can you determine if the fluid is really urine?
Compare creatinine and potassium levels to that of peripheral blood. These values should be about twice as high in the urine.
You can also perform a positive contrast retrograde urethrocystogram
Vessels and nerves that must be preserved while performing a perineal herniorrhaphy
Internal pudendal and caudal rectal vessels
Caudal rectal nerve
What two major veins form the portal vein?
Cranial and caudal mesenteric veins
What are the major tributaries to the portal vein after its formation by the confluence of the cranial and caudal mesenteric veins?
Splenic, gastroduodenal and right gastric vein
What structures are drained by the portal vein?
“collects blood from the pancreas, spleen, and the entire gastrointestinal tract except the caudal rectum and anal canal. ”
Excerpt From
Miller’s Anatomy of the Dog
Howard E. Evans & Alexander de Lahunta
https://books.apple.com/us/book/millers-anatomy-of-the-dog/id875302085
This material may be protected by copyright.
Describe the blood supply to the maxilla and mandible
Maxilla: blood supply originates from the common carotid arteries. Paired major and minor palatine arteries emerge from the major Palatine foramen on the caudal edge of the fourth upper premolar. Major palatine arteries course rostrally, anastomosing caudal to the incisors. The minor palatine arteries enter the palate at the level of the last molar, caudal and slightly lateral to the major palatine foramen. The minor palatine arteries course caudomedially and ramify in the caudal hard palate and soft palate. The soft palate is also supplied by branches of the ascending pharyngeal artery.”
Mandible: the mandibular alveolar artery enters the mandibular canal on the medial surface of the mandible and ends at the middle mental foramen, where it branches to form the caudal, middle and rostral mental arteries which exit via the mental foramina.
What is known as the Von Langerbeck technique? What is the main disadvantage? What age consideration should be taken into account? What technique can be used instead and why?
“The two procedures most often used to repair secondary clefts are sliding bipedicle flaps and overlapping flap techniques. Sliding bipedicle flaps (von Langenbeck technique) are created to close hard palate defects. The disadvantage of this technique is that the repair is unsupported and directly over the defect. Staged repair can be done to increase coverage of palatal defects.
“Palatoplasty performed before 16 weeks of age may hinder maxillofacial growth and development. Although rare, a narrower maxilla and occlusal problems may result. ”
“An alternate technique for repair of hard palate defects is the overlapping “sandwich” technique (Figs. 18.19 and 18.20). This technique is advantageous because it does not place the repair over the palate defect.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What muscle must be apposed/included in the correction of a primary palatal defect to avoid premature dehiscence?
Orbicularis oris
Which axial pattern flap is considered the most robust choice for the repair of palatal fistulas ?
Angularis oris artery (A branch of the facial artery)
What mucosal flap technique is preferred for the repair of large, centrally located palatal fistulas? how is it performed?
Double flap technique
“A double-layer flap technique may be performed using tissue surrounding the fistula and a flap from the mucoperiosteum of the hard palate. Create the first flap (gingival dashed line) by rotating the gingival margins of the fistula medially and apposing with sutures (top inset). Cover this flap (bottom insert) with a rotational mucoperiosteal hard palate flap (palatal dashed line).”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What technique can be used in cats for the repair of small palatal fistulas?
Conchal cartilage graft repair
What cartilage based technique can be utilized for the repair of small, centrally located palate defects in dogs?
Vertical ear canal graft repair
Name 4 drugs associated with the development of esophageal strictures
“tetracycline, doxycycline, nonsteroidal antiinflammatory drugs, or ciprofloxacin”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Following injury caused by foreign body, what is the process by which an esophageal stricture will develop?
“To produce a stricture, esophageal damage must generally involve the muscular layers and affect most of the circumference in a focal area. The mucosal defect is then replaced by epithelial migration. The gap in the muscle is filled by fibrous connective tissue, and wound contraction and collagen remodeling reduce the width of the scar. This leads to narrowing of the esophageal lumen, which may cause obstruction.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
In what part of the esophagus are strictures most likely to be observed?
Lower 1/3 (high pressure zone)
Name 8 possible differentials for regurgitation other than esophageal strictures
“Vascular ring anomalies, extraluminal masses, esophageal neoplasia, foreign bodies, esophagitis, gastroesophageal intussusception, esophageal diverticulum, hiatal hernias, megaesophagus, and cricopharyngeal dysfunction are other possible causes of regurgitation that must be differentiated from esophageal stricture.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the two techniques most commonly utilized in the treatment of esophageal stricture’s?
Ballon dilation or bougienage
Explain the difference between a pulsion diverticulum and a traction esophageal diverticula
“A pulsion diverticulum is a herniation of the mucosa through the muscular layers of the esophagus. These diverticula are produced by exaggerated intraluminal pressure in association with abnormal regional peristalsis or when obstruction interferes with normal peristalsis. “The wall of a pulsion diverticulum consists of only esophageal epithelium and connective tissue.”
“Traction diverticula are distortions, angulations, or funnel-shaped bulges of the full-thickness wall of the esophagus caused by adhesions resulting from an external lesion. “The wall of a traction diverticulum consists of adventitia, muscle, submucosa, and mucosa.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the two most common sites for esophageal diverticula ?
Distal cervical esophagus cranial to the thoracic inlet or distal thoracic esophagus just cranial to the diaphragm
Diagnostic test most commonly utilized to diagnose esophageal strictures an diverticula
Esophagogram
What two conditions (1 pathologic and another breed related) can be misdiagnosed as esophageal diverticula?
“Dogs and cats with generalized megaesophagus tend to have greater outpouching of the esophageal wall cranial to the base of the heart. Brachycephalic dogs and shar peis often have a loop of redundant esophagus cranial to the base of the heart. Do not misdiagnose these animals as having diverticula.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
List three methods by which an esophageal diverticula might be surgically treated
“Position a thoracoabdominal (TA; linear) or GIA (gastrointestinal anastomosis) stapling device along the base of the diverticulum and fire. Transect and remove the diverticulum without contaminating the surgical site. If stapling equipment is not available, suction the esophageal lumen and place noncrushing forceps across the proposed transection site. Transect the diverticulum and appose the edges as for esophagotomy with a one- or two-layer simple appositional pattern”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What parasite is associated with the development of esophageal masses similar to neoplasia? What clinical findings may also be observed in these patients?
Spirocerca lupi
Intermediate host is a beetle which must be ingested for infection to occur.
Hypertrophic osteopathy maybe observed
Best diagnosed via CT scan or esophagoscopy
What are the four main types of esophageal hernias?
Sliding hernia
Paraesophageal hernia
Combined sliding and Paraesophageal
gastroesophageal intussusception
What is the main radiographic difference between hiatal hernias and peritoneopericardial or traumatic diaphragmatic hernias?
Hiatal hernias are typically located in the plane of the caudal mediastinum (dorsal 1/3 of thorax on lateral projection)
Describe the typical approach and surgical technique utilized for the treatment of hiatal hernias
“Make a cranial ventral midline incision extending caudal to the umbilicus to expose the diaphragm and stomach. Retract the left lobes of the liver medially to expose the esophageal hiatus. Pass a stomach tube (28- to 32-Fr) to help identify and manipulate the esophagus. Grasp the stomach and reduce the hernia with gentle traction. Examine the hiatus. Dissect the phrenicoesophageal membrane, freeing the esophagus from the diaphragm ventrally. Preserve the vagal trunks and esophageal vessels during dissection. Place an umbilical tape sling around the abdominal esophagus to displace it caudally and facilitate manipulations. Perform a diaphragmatic hiatal plication-reduction, esophagopexy, and left-sided fundic gastropexy. Accomplish diaphragmatic hiatal plication-reduction by excoriating or debriding the margins of the hiatus and then place three to five sutures (2-0 polydioxanone or polypropylene) to appose the edges and narrow the hiatus. “Perform plication around a large stomach tube (28- to 32-Fr) (see Fig. 18.60). Reduce the hiatus to 1 or 2 cm, a size that allows passage of one finger. Accomplish esophagopexy by placing sutures (3-0 or 2-0 polydioxanone or polypropylene) from the remaining margin of the hiatus through the adventitia and muscular layers of the abdominal esophagus. Complete the repair with either a left-sided tube gastropexy or incisional gastropexy (see pp. 406–408). Fix the fundus with slight to moderate caudal traction to prevent cranial movement of the gastroesophageal junction into the thorax. Evacuate air from the chest by thoracentesis or tube thoracostomy and lavage and close the abdomen.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the most common Complications observed after surgical treatment of hiatal hernias?
Dysphasia is common for several days
Over reduction of the hernia, requiring reoperation
Infection (typically caused by penetration of the esophagus or gastric lumen with sutures or tubes
What kind of patient is considered at highest risk for the development of gastroesophageal intussusception?
Immature animals with megaesophagus
German Shapherd
What is the typical presentation of a patient with gastroesophageal intussusception?
Acute onset of regurgitation, vomiting, dyspnea, abdominal discomfort and possibly death. Rapid deterioration within 1 to 3 days. Mimics aspiration pneumonia, making diagnosis difficult. Approximately half of affected animals have a history of esophageal disease.
What is the mortality rate for patients with gastroesophageal intussusception?
95%
What caution must a surgeon observe when incising the pyloric area during a Billroth I procedure?
“Use extreme care when incising in the pyloric area to avoid damaging the common bile duct where it traverses the lesser omentum.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Heineke-Mikulicz pyloroplasty - describe
“Heineke-Mikulicz pyloroplasty allows limited exposure of the pyloric mucosa for biopsy and is easy to perform. Make a full-thickness, longitudinal incision in the ventral surface of the pylorus (Fig. 18.73). Place traction sutures at the center of the incision, and orient the incision transversely. Suture the transverse incision in a one-layer pattern (simple interrupted or crushing) using 2-0 or 3-0 absorbable suture. Place the sutures carefully so that the incision edges are properly aligned and tissue inversion is avoided.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
How long must a tube gastropexy remain in place before it can be safely removed?
10 days
GDV Mortality rate in treated animals
20-45%
GDV risk factors (7)
“Male sex, increasing age, being underweight, being fed a large volume of food per meal, eating one meal (especially a large volume meal) per day, eating rapidly, having a raised feeding bowl, and having a fearful temperament are predisposing factors that may increase a dog’s risk of GDV. Having a deeper and narrower thorax may change the anatomic relationship between the stomach and esophagus such that the dog’s ability to eruct is impaired. Feeding dogs from a raised feed bowl may increase the risk of GDV because it may promote aerophagia.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
7 recommendations for owners of dogs at high risk for GDV
“Feed several small meals a day rather than one large meal.
• Avoid stress during feeding (if necessary, separate dogs in multiple-dog households during feeding).
• Restrict exercise before and after meals (of questionable benefit).
• Do not use an elevated feed bowl.
• Do not breed dogs with a first-degree relative that has a history of gastric dilatation-volvulus.
• For high-risk dogs, consider prophylactic gastropexy.
• Seek veterinary care as soon as signs of bloat are noted.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the expected position of the spleen in a case of GDV ?
“The spleen is usually displaced to the right ventral side of the abdomen.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Discuss the cardiovascular consequences of GDV, with mentioning of cardiac arrhythmias and reperfusion injury
“Caudal vena cava and portal vein compression by the distended stomach reduces venous return and cardiac output, causing myocardial ischemia. Central venous pressure, stroke volume, mean arterial pressures, and cardiac output are reduced. Obstructive shock and inadequate tissue perfusion affect multiple organs, including the kidneys, heart, pancreas, stomach, and small intestine. Cardiac arrhythmias occur in many dogs with GDV, particularly those with gastric necrosis. Arrhythmias may contribute to mortality and require appropriate monitoring and treatment (see discussion under Postoperative Care and Assessment on p. 423). Myocardial depressant factor has also been recognized in affected dogs, and cardiac damage is common, as seen by increased serum concentrations of troponin. Reperfusion injury has been implicated as causing much of the tissue damage that ultimately results in death after correction of GDV. Early treatment with IV lidocaine (2 mg/kg IV bolus) before decompression followed by CRI of lidocaine (0.05 mg/kg per min) for 24 hours appears to decrease the occurrence of cardiac arrhythmias, acute kidney injury, and hospitalization in dogs with GDV, possibly by mitigating reperfusion injury.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What precautions must be taken when obtaining radiographs in a patient with suspected GDV?
“Caution! Positioning these animals for a ventrodorsal view may lead to aspiration. Remember that the right lateral and dorsoventral views are preferred when attempting to diagnose GDV.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Statistically speaking, what can be said of the use of lactate to determine the presence of gastric necrosis and estimate prognosis in patients with GDV?
Reasonably specific (88%) but not very sensitive (50%)
When do ventricular arrhythmias typically begin following GDV?
12 to 36 hours
What percentage of GDV dogs develop DIC?
30%
Percentagent of dogs who develop a recurrence of GDV if gastropexy is not performed?
80%
What is the recommended procedure for treatment of pyloric mucosal hypertrophy?
Y-U pyloroplasty
What is the recommended procedure when both the mucosa and muscular layers of the pylorus are so thick as to make the area inflexible?
Billroth I
What is the difference between a gastric ulcer in a gastric erosion?
An ulcer is a mucosal defect that extends through the muscularis mucosa and into the submucosa or deeper layers. Erosions do not penetrate the muscularis mucosa.
Where is gastrin produced? What is its effect?
Gastric antral G cells, in response to vagal stimulation and gastric distention
Stimulates gastric acid secretion
Zollinger-Ellison syndrome - explain
“Zollinger-Ellison syndrome is a condition in which hypersecretion of gastrin is associated with neoplasia of the non-β pancreatic islet cells. Severe duodenal ulceration is seen with this disease, and removal of the pancreatic mass may be necessary to alleviate clinical signs (see p. 613). Because of the aggressive biological behavior of this malignant neoplasm, the prognosis for long-term cure is poor; however, aggressive medical management with omeprazole (1–2 mg/kg given orally twice a day) may palliate the disease for a year or more.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
When is dehiscence most likely to occur after intestinal surgery? Why?
“Healing is functionally weakest at the end of the lag phase because of fibrinolysis and collagen deposition; therefore dehiscence most commonly occurs 3 to 5 days after intestinal surgery. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the most common gastric tumor found in dogs and cats? Malignant or benign? What percentage of gastric tumors are expected to be consistent with this kind of neoplasia?
Adenocarcinoma
Malignant
60-70% of cases
Why should hypotension/dehydration be corrected ASAP, particularly prior to GI surgery?
“Alleviating hypotension is important because it is associated with intense portal vasoconstriction that causes the breakdown of the intestinal mucosal barrier, allowing increased endotoxin absorption”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What biochemical abnormalities are expected to be observed in patients with reoccurring vomiting? Is there a difference between gastric and duodenal vomiting?
“Profuse vomiting typically results in dehydration and may cause hypochloremia, hypokalemia, and/or hyponatremia. Duodenal vomitus may cause greater sodium, potassium, and water losses than gastric vomiting. Alkalosis generally occurs with loss of gastric fluid; however, metabolic acidosis may occur due to fluid depletion from vomiting, insensible water losses, lack of intake, and/or catabolism of body stores. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
At what serum albumin level should whole blood, plasma or hetastarch transfusion be considered?
“Administration of plasma (5–20 mL/kg), whole blood transfusions, or hetastarch several hours before surgery should be considered if serum albumin concentrations are below 1.5 g/dL”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
You are presented with a hypoalbuminemic patient also affected by protein-losing enteropathy. What fluid/transfusion choice is most likely adequate to increase coloidosmotic pressure?
“If the patient has a severe protein-losing enteropathy, administration of plasma is seldom effective in raising the serum albumin concentration because most of the albumin is quickly lost into the GI tract. Therefore hetastarch is usually preferred.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the vertebral ratio scoring system utilized to gauge intestinal distention in cats
“A ratio of the maximum diameter of the small intestine to the height of the cranial end plate of the second lumbar vertebrae of greater than 3 is strongly associated with intestinal obstruction in cats, whereas a ratio of greater than 4 is nearly always associated with obstruction.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Dog with suspected intestinal perforation. Which diagnostic modality should be avoided? What can be used instead?
“Do not use barium sulfate for a gastrointestinal radiographic study if intestinal perforation is suspected. Instead, document peritonitis by abdominocentesis, diagnostic peritoneal lavage, or exploratory surgery. Iodinated contrast media can be used, but U/S is typically favored.
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Reasons why a patient should undergo emergency abdominal ex-loration (7)
1) Penetrating abdominal injury
2) Effusion with intracellular bacteria
3) Blood-to-peritoneal fluid glucose difference >20 mg/dL
4) Peritoneal fluid lactate >2.5–5.5 mmol/L
5) Imaging reveals spontaneous extraluminal gas bubbles or volvulus
6) Esophageal or gastric intussusception is identified
7) Bacteria isolated from peritoneal fluid”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What opens in the major duodenal papilla in the dog? How about the minor duodenal papilla?
“The common bile duct and pancreatic duct open in the first few centimeters of the duodenum at the major duodenal papilla in dogs. The accessory pancreatic duct enters caudal to this at the minor duodenal papilla.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Is the ascending duodenum located to the right or left of the mesenteric roote?
Left
What is the recommended biopsy technique for intestinal masses prior to surgery?
Ultrasound guided, fine meedle aspirate using spinal needle or Wescott biopsy needle. Tru-cut needle if mass larger than 2 cm. Do not penetrate mucosa.
What precaution should be taken when performing a laparoscopic small intestinal exploration?
Each intestinal segment must be returned to the abdomen as exteriorization of the entire small intestine is not possible without compromising blood supply. The duodenum and ileum are not readily accessible. 
You are performing an abdominal exploratory with the intention of obtaining multiple organ biopsies, including G.I. tract. In what order should the biopsies be obtained? What should be done before obtaining the samples? How large should the small intestinal samples be?
Begin by performing a thorough exploratory before obtaining any samples. Obtain samples of lymph nodes, liver and other tissues before gastric or intestinal procedures to prevent contamination. Obtain reasonably large intestinal samples (4 to 5 mm in diameter), using longitudinal or transverse enterotomy incisions. 
How do stapled anastomosis perform in comparison to suture anastomosis?
“Stapled anastomoses have a higher tensile strength than sutured anastomoses after 7 days. They heal by primary intention with minimal inflammation.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
List the advantages associated with the use of a serosal patch to protect small intestinal suture line. What serosal surfaces can be utilized?
“Serosal patching provides support, a fibrin seal, increased resistance to leakage, and blood supply to the damaged area plus it may prevent intussusception. Patches are commonly used after intestinal surgery when closure integrity is questioned or when dehiscence is repaired. Patches that span visceral defects are covered with mucosal epithelium within 8 weeks. Most commonly, jejunum adjacent to the defect or area of questionable viability is used for the serosal patch. Other sources could include the stomach, other intestinal segments, abdominal wall, or the urinary bladder. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the three most important factors that determine the optimal healing conditions for the small intestines?
Good blood supply
Accurate mucosal apposition
Minimal surgical trauma
What are the current thoughts regarding inverting or everting patterns for intestinal anastomosis?
“Inflammation is more severe and healing time is slower with inverting patterns than with approximating patterns. Everted intestinal anastomoses have reduced tensile and bursting strength during the lag phase and therefore have a greater tendency to leak. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the three phases of intestinal healing and their approximate duration?
Lag phase (days 0 to 5)
Proliferative phase (days 3 to 14)
Maturation phase (days 10 to 180)
What are the current thoughts regarding the timing of feeding after intestinal surgery? What are the proposed benefits of this approach?
“Small amounts of water may be offered 8 to 12 hours after surgery. If no vomiting occurs, small amounts of food may be offered 12 to 24 hours after surgery. Early feeding is important as it preserves or increases GI blood flow, prevents ulceration, increases IgA concentrations, stimulates other immune system defenses, and stimulates wound repair.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What three IN-HOUSE diagnostic tests should be immediately performed if you suspect that a patient may be developing peritonitis after a gastrointestinal surgery?
“abdominocentesis, chemistry profile, and CBC ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Your suspect that a patient who underwent gastrointestinal surgery is developing Peritonitis. You obtain abdominal fluid for culture, but while the results are pending you must begin antibiotic therapy. List three antibiotic combinations that would be adequate in this case. 
“cefazolin, cefoxitin, enrofloxacin plus ampicillin, clindamycin plus enrofloxacin”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
 List three risk factors associated with a high risk of developing small intestinal leakage after enterotomy
Pre-operative peritonitis
Intestinal foreign body
Serum albumin concentration less than or equal to 2.5 g/dL
What is the approximate mortality rate associated with small intestinal dehiscence?
83%
How much of the small intestines must be resected to create a significant risk of developing short bowel syndrome? What are the typical clinical signs associated with his syndrome?
70 to 80% of the small intestine must be resected
Weight loss, diarrhea and malnutrition
How is short bowel syndrome typically treated?
Nutritional support (most important factor)
Glutamine supplementation (2012 study)
Proton pump inhibitors
Antibiotics (Tylosin)
Anti-diarrhea opioids (loperamide)
What is the major cause of mortality associated with upper small intestinal obstruction?
“The major cause of mortality from upper small intestinal obstruction is severe hypovolemia with electrolyte disturbances. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the normal intraluminal pressure within the small intestines during resting and during peristalsis? At what pressure does venous drainage cease, leading to intestinal wall hypoperfusion and ischemia?
Resting pressure 4 mmHg
Peristaltic pressure 15 to 25 mmHg
Venous drainage is interrupted at 50 mmHg
Ileus may be physiologic or a result of intestinal obstruction. In general terms, what is the difference between the two on radiographs?
“anatomic or mechanical ileus is often focal, whereas physiologic or functional ileus is usually generalized.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What precaution should be taken immediately before taking a patient suspected of having a gastric or intestinal foreign body into surgery?
Repeat abdominal radiographs to make sure the foreign body has not already moved into the colon
List three common causes of physiologic ileus
Parvovirus, peritonitis, pancreatitis
What approach can be taken to a cat presented with a linear foreign body under the tongue who is still not grossly dehydrated or painful?
“Linear foreign bodies lodged at the base of the tongue in cats that are presented 1 to 3 days after ingestion may be cut and then monitored for passage, depending on how ill the cat appears. If the cat does not obviously feel better within 6 hours of cutting the foreign body off the tongue, it should be taken to surgery.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe which alternative technique can be used for the removal of linear foreign bodies which have not penetrated the mucosa and are not embedded in the mesenteric border
“Make an incision into the stomach or intestine at the site where the object is fixed. Suture the linear object to a soft catheter and then completely advance the catheter into the distal intestine. Close the enterotomy site and milk the catheter and foreign body through the intestinal tract and out through the anus. This technique reduces the number of enterotomies and may thereby reduce the risk of leakage and dehiscence.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Intestinal tumors: where do they most commonly occur in the dog versus the cat?
Dog: Rectum or colon
Cat: Small Intestines
Where are the three most common small intestinal malignancies and dogs and cats?
Adenocarcinoma, lymphosarcoma and leiomyosarcoma
What suture type should be used when performing an enterotomy or RNA in a hypoalbuminemic patient?
Monfilament non-absorbable (nylon, prolene or polybutester)
What is the typical ultra sonographic appearance of intestinal intussusception?
“Ultrasound reveals target or bull’s-eye pattern (concentric intestinal layers).”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the most common causes of intussusception in young versus old dogs?
Young animals: enteritis secondary to parvovirus infection or parasitism
Older animals: enteritis, systemic ilness, neoplasia
Describe the sequence of events that leads to the formation of an intussusception
“Initially, invagination causes partial intestinal obstruction, which may progress to complete obstruction. Vessels attached to the intussusceptum collapse because of increased intraluminal pressure or kinking, and those vessels may avulse. The wall becomes edematous, ischemic, and turgid. Blood extravasates into the lumen, and the serosa fissures. Fibrin seals the layers of the intestine together and may help localize peritonitis as wall necrosis occurs. Eventually intestinal devitalization occurs, with subsequent contamination of the abdominal cavity. Intussusceptions may occur as agonal events (i.e., are incidental findings and not the cause of death). Agonal intussusceptions are easily reduced and are associated with minimal inflammation; intestinal walls are not edematous, and fibrin does not seal the layers of intestine together.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Canine and feline breed predisposed to intussusception
German Shepherd and Siamese
What should be done at the time of surgery to correct and intussusception in hopes of determining the cause?
Intestinal biopsy
Roughly what percentage of patients with intussusception will reoccur if enteroplication is not performed?
30%
Describe the sequence of events following intestinal (mesenteric) torsion
“Twisting compromises the cranial mesenteric artery and all its branches, compromising blood flow to the distal duodenum, jejunum, ileum, cecum, ascending colon, transverse colon, and proximal descending colon. The ensuing rapid cascade of vascular obstruction, intestinal anoxia, circulatory shock, endotoxemia, and cardiovascular failure results in death if the condition is not corrected immediately. Mesenteric twisting reduces venous return and arterial perfusion. The arteries and veins may thrombose. Edema and congestion of the intestinal wall lead to anoxia. Blood is lost into both the intestinal lumen and the abdominal cavity. Motility is disrupted, and the normal bacterial flora proliferates rapidly both proximal to and within the strangulated intestine. Small intestinal bacterial concentrations may increase to 108 to 1011/mL within 6 hours of strangulation. Endotoxins (primarily from E. coli) and exotoxins from Clostridium spp. are produced. These toxins and bacteria escape into the abdomen through the damaged mucosal barrier and are absorbed into the systemic circulation. Significant production of inflammatory mediators locally and in other organs such as the liver and lung promote systemic inflammation, leading to systemic compromise and organ dysfunction. Death from strangulation obstruction usually results from a combination of hypovolemic shock, sepsis, and products of tissue necrosis[…]”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the main type of bacteria producing endotoxins and exotoxins in a case of G.I. obstruction?
E. coli (endotoxin)
clostridium (exotoxin)
Risk factors for the development of mesenteric torsion your dogs
Vigorous activity
Dietary indiscretion
Recent G.I. surgery
Enteritis
Parvovirus infection
Exocrine pancreatic insufficiency
Concurrent GDV
Foreign bodies
Intussusception
Typical Signalment of dogs affected by mesenteric torsion 
Mail medium to large sporting or working dog. German Shepherd’s (often with concurrent pancreatic insufficiency and English pointers. Typically young (3 to 4 years of age)
Radiographic appearance of mesenteric torsion
The entire intestinal tract is uniformly distended with gas
Intestinal loops lying parallel to each other
Loss of serosal detail
“A “coiled spring” appearance when the colon is filled with air (or barium) indicates a possible…
Cecal-colic intussusseption
What measures can be taken to reduce colonic bacterial numbers prior to surgery?
Switch diet to highly digestible option (hamburger with rice) 72 hours pre-op
Withhold food for 24 hours
Administer enema with colon lavage solution like Colyte to clear the colon, followed by a 10% povidone iodine enema to reduce bacterial numbers

Describe the arterial, venous and nervous supply to the large intestines
“The blood supply to the large bowel is from the ileocolic artery, a branch of the cranial mesenteric artery, and the caudal mesenteric artery. These major branches run parallel to the intestine, giving off short vasa recta vessels, which penetrate the intestinal wall. Branches of the ileocolic and left colic artery anastomose. The ileocolic artery supplies the ileum, cecum, and ascending and transverse colon. It gives rise to the middle colic and right colic arteries. The right colic artery supplies the cecum, the ascending colon, and part of the transverse colon. The middle colic artery supplies part of the transverse colon and half of the descending colon; it anastomoses with the left colic artery, which supplies the distal half of the descending colon. The left colic and cranial rectal arteries originate from the caudal mesenteric artery. The cranial rectal artery primarily supplies the cranial rectum but also sends several vasa recta to a short segment of the terminal colon. The internal iliac artery supplies branches to the rectum via prostatic or vaginal artery branches. Venous drainage essentially mirrors arterial supply. The caudal mesenteric vein is short and enters the portal vein. The vagus and pelvic nerves supply the colon[…]”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
How do stapled colonic anastamosis compare to suturing techniques?
“Although more expensive, stapled anastomoses show less tissue reaction, more mature fibrous connective tissue, greater tensile strength, fewer mucoceles and necrotic areas, and less luminal stenosis than suture techniques. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Discuss the limitations associated with the use of staplers for intestinal anastomosis in the colon
“Thick, inflamed, and edematous tissues may prevent proper firing of the stapler by preventing complete penetration and formation of the staples into the B-shape. Dilatation causes thinning of the visceral walls and may result in tissues that are too thin for the staples to be effective. In such cases, a suture anastomosis should be performed. Circular, inverting, end-to-end staplers are often used to anastomose the colon. It is easier to use end-to-end staplers in the colon than in other areas of the GI tract because the instrument can be introduced through the anus rather than a separate enterotomy or gastrotomy incision. The colon of most adult animals can accommodate the size of available staplers. Transanal introduction of the stapler may not be possible in all cats and small dogs because of the small anus and narrow pelvic canal.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
How much of the colon can be resected in small animals without adverse effects? Which species tolerate even more aggressive resections?
70%. Cats can tolerate up to 90 to 95%, but this should be avoided in dogs.
What vessels are ligated when performing a subtotal colectomy with preservation of the ileocolic junction?
Right Colic artery
Middle colic artery
Left colic artery
Cranial rectal artery (cats only)
What arteries are ligated when performing a subtotal colectomy and ileocolic anastomosis?
Ilial arteries
Right colic artery
Middle Colic artery
Left colic artery
Cranial rectal artery (only cats)
What suturing technique can be used to avoid excessive mucosal protrusion during intestinal anastomosis?
“Angle the needle such that slightly more serosa than mucosa is engaged with each bite to help prevent the mucosa from protruding between sutures ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe one technique that can be used to overcome luminal diameter disparity between intestinal segments during a resection and anastomosis
“Luminal disparity that cannot be accommodated by the angle of the incisions or suture spacing is usually correctable by resecting a small wedge (1–2 cm long, 1–3 mm wide) from the antimesenteric border of the intestine with the smaller lumen (see Fig. 18.107). This enlarges the stomal perimeter and gives it an oval shape.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Briefly discuss the technique for performing a functional end to end stapled anastomosis
“For a functional end-to-end anastomosis, use a linear cutting stapler and a transverse stapler. Fully insert (50 mm) the linear cutting stapler into the stomas of each intestinal loop and activate it. Separate the stapled suture line, and apply the transverse stapling instrument to close the anastomosis.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the technique utilized to perform a typhlectomy
“Begin typhlectomy for a noninverted cecum by double ligating the cecal branches of the ileocecal artery in the ileocecal mesenteric attachment (ileocecal fold) (Fig. 18.131A). Dissect the ileocecal fold, freeing the cecum from the ileum and colon (see Fig. 18.131B). Place a clamp across the base of the cecum (see Fig. 18.131C). Milk intestinal contents from the ascending colon and ileum adjacent to the cecocolic orifice and occlude the lumen. Transect the cecum where it joins the ascending colon. Close the defect with simple interrupted sutures. As an alternative, place a transverse or linear cutting stapling instrument across the base of the cecum. Activate the stapler. Transect the cecum before removing the transverse stapling instrument. Lavage, then cover the surgical site with an omental or serosal patch (see p. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the four most important factors upon which optimal healing of the colon depend?
“Optimum healing depends on a good blood supply, accurate mucosal apposition, minimal surgical trauma, and a tension-free closure. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Name three of the most common anaerobic bacteria found in the colon
“Bacteroides spp.
• Bifidobacterium spp.
• Lactobacillus spp.
• Clostridium spp.
• Fusobacterium spp.
• Anaerobic Streptococcus spp.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Name the three most important gram-negative bacteria found in the colon
‘PEK”
• Proteus spp.
• Escherichia coli
• Klebsiella spp.
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Name the three most important gram-positive bacteria found in the colon
“SEC”
•Staphylococcus spp.
• Enterococcus spp.
• Corynebacterium spp.
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
How long should antibiotics be used after colonic surgery if no signs of peritonitis are present?
“Antibiotics may be discontinued 2 to 4 hours after surgery unless peritonitis is present”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the possible complications associated with bilateral pubic and Ischial osteotomy, typically performed to improve the access to the pelvic colon/rectum?
“Animals undergoing bilateral pubic and ischial osteotomy for pelvic dissection are expected to become ambulatory within 3 days of surgery but may exhibit signs of lameness prior to becoming fully ambulatory by 7 days after surgery. Towel support when walking on slick floors is recommended due to exposure of and potential compromise of the obturator nerves.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Is the frequency of leakage at the anastomotic site for the colon different between stable and suture techniques? What can be done to minimize the chance of leakage?
“The frequency of leakage at the anastomotic site is similar for staple and suture techniques. Leakage may be minimized by placing a serosal patch around the anastomosis”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the overall frequency of fecal incontinence after rectal pull-through surgery? How long does it usually last?
“One study showed that complications of rectal pull-through are frequent (78%), with the most common being fecal incontinence (56%).45 Incontinence may be transient (45%) and lasting approximately 2 weeks. The likelihood of permanent incontinence was 13 times greater with complete rectal pull-through surgery compared with a partial procedure. Diarrhea (55%), tenesmus (39%), stricture (27%), constipation (12%), rectal bleeding (14%), dehiscence (10%), and infection (7%) were also reported.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What to dog breeds are predisposed to histiocytic ulcerative colitis?
Boxers and French bulldogs
Which three groups of differential diagnosis must be ruled out before the diagnosis of idiopathic megacolon can be made?
Mechanical, neurologic and Endocrine causes
Describe the anatomy of the rectum, including the mesorectum, pertinent inervation, and musculature composing the pelvic diaphragm
“The cranial rectum is attached to the sacrum by the mesorectum. The mesorectum does not cover the entire rectum; the terminal rectum is retroperitoneal. At the level of the second caudal vertebra, the mesorectum reflects onto the sides of the pelvis as parietal peritoneum, forming a pararectal fossa on each side. The peritoneal reflection is cranial to the rectococcygeus muscles and contains the autonomic nerve fibers of the pelvic plexus that innervate the rectum. The pelvic plexus is paired, composed of parasympathetic pelvic and sympathetic hypogastric nerves, and lies dorsal to the prostate in males (see p. 727). The caudal part of the rectum is supported by the levator ani muscles medially and coccygeus muscles laterally. The external anal sphincter muscle demarcates the caudal limit of the rectum.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What nerve structures are contained within the peritoneal reflection?
“The peritoneal reflection is cranial to the rectococcygeus muscles and contains the autonomic nerve fibers of the pelvic plexus that innervate the rectum”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the three zones of the rectal canal? What do they contain?
“the columnar zone, the intermediate zone, and the cutaneous zone. The innermost (columnar) zone has a series of longitudinal mucosal and submucosal ridges called anal columns or pillars. The pockets between these columns are the anal sinuses, which extend caudally and end in blind pouches under the anocutaneous line. The columnar zone varies from 3 to 25 mm in length. The intermediate zone is usually less than 1 to 2 mm wide but forms a distinct, raised, circumferential ridge called the anocutaneous line. Anal glands are found in the columnar and intermediate zones. The outermost (cutaneous) zone has fine hairs but appears as hairless skin. Sebaceous, circumanal, and apocrine sweat glands are found only in the cutaneous zone. The anus is the external opening of the anal canal.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the blood supply to the rectum and why this matters when performing rectal surgery in the dog
“The cranial rectal artery is a branch of the caudal mesenteric artery and is the major blood supply to the rectum. Blood supply from the middle rectal artery (from the internal pudendal branch of the internal iliac artery) and caudal rectal artery (from the middle caudal branch of the median sacral artery or from the internal pudendal branch of the internal iliac artery) varies and is relatively insignificant. To ensure an adequate anastomotic blood supply, the cranial rectal artery in dogs should be preserved unless the intrapelvic rectum is resected. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the muscular anatomy, nerve supply and blood supply to the anus
“The internal and external anal sphincter muscles surround the terminal rectum and anal canal to control defecation. The anal sacs lie between these two muscles on each side of the anus (see p. 494). The internal anal sphincter is a caudal thickening of the circular smooth muscle lining the anal canal. It is an involuntary smooth muscle that works with other muscles of defecation to prevent indiscriminate defecation. It is innervated by the parasympathetic branches of the pelvic nerve (S1–S3), which are inhibitory. Motor fibers from the hypogastric nerves are sympathetic to the internal anal sphincter. The external anal sphincter is a large, circumferential band of skeletal (striated) muscle chiefly responsible for fecal continence. It is wider dorsally than ventrally where its fibers decussate and spread to insert on the urethra and bulbospongiosus muscle. The only voluntary nerve supply to the external anal sphincter comes from the caudal rectal branches of the pudendal nerves. The blood supply to the external anal sphincter is from the perineal arteries. See p. 499 for the surgical anatomy of the pelvic diaphragm.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Where does the external anal sphincter derive its voluntary nerve supply?
“The only voluntary nerve supply to the external anal sphincter comes from the caudal rectal branches of the pudendal nerves”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What three structures (one nerve and two vessels) should be carefully preserved when performing a lateral approach to the rectum?
Caudal rectal nerve (branch of pudendal N)
Internal pudendal artery
Internal pudendal vein
There are two main techniques utilized for the removal of the anal sacs. Which one is preferred and why?
“The closed technique is preferred because the external anal sphincter muscle is not transected, and the lumen of the anal sac remains closed, preventing contact between secretions and adjacent tissues. See p. 495 for a description of open and closed anal sacculectomy techniques.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the most common cause of incontinence during rectal surgery?
“Incontinence with extensive rectal resection results from loss of rectal afferent nerves or from disruption of the pelvic plexus at the peritoneal reflection”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the approximate complication rate for anal sacculectomy? What percentage can affect defecation?
“Complications associated with anal sacculectomy may be self-limiting (32%) or may affect defecation (14%).”
Permanent incontinence is unusual.
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Perianal adenomas are the most common canine perianal tumor (80%). They are frequently observed in dogs also affected by another tumor. Which and where?
Testicular interstitial cell tumor
How much of the anal sphincter can be removed with hopes that fecal continence will return within a few weeks?
50%
And what kind of monitoring should be performed in a hypercalcemic patient who just underwent the removal of an apocrine gland adenocarcinoma (anal sac)
“The serum calcium concentration should be monitored at least daily for the first 2 days. Hypercalcemia should be treated until the serum calcium level is normal. Most animals become normocalcemic within 24 hours of primary tumor resection; however, some become hypocalcemic and require calcium supplementation to prevent tetany.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the four types of perineal hernias including muscles involved? Which one is the most common?
“Most herniations occur between the levator ani, external anal sphincter, and internal obturator muscles (caudal hernia); however, some occur between the sacrotuberous ligament and coccygeus muscle (sciatic hernia), levator ani and coccygeus muscles (dorsal hernia), or ischiourethralis, bulbocavernosus, and ischiocavernosus muscles (ventral hernia).”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the anatomy of the pelvic diaphragm including muscles, their origin and insertion, nerves and blood vessels.
“The pelvic diaphragm is composed of the paired medial coccygeal and levator ani muscles. The paired levator ani muscle originates from the floor of the pelvis and medial shaft of the ilium, fans out around the sides of the rectum, and then narrows and inserts ventrally on the seventh caudal vertebra. The paired coccygeus muscle is a thick muscle lying lateral to the thin levator ani. The coccygeus originates from the ischiatic spine on the pelvic floor and inserts ventrally on the second to fifth caudal vertebrae.
The paired rectococcygeus muscle arises from the external longitudinal musculature of the rectum caudal to the levator and coccygeus muscles and inserts on the ventral surface of the fifth to sixth caudal vertebrae. The rectococcygeus muscle shortens the rectum when the tail is raised during defecation. The peritoneal reflection is cranial to the rectococcygeus muscles. The sacrotuberous ligament in the dog is a fibrous band running from the transverse process of the last sacral and first caudal vertebrae to the lateral angle of the ischiatic tuberosity rostral to the pelvic diaphragm. Cats do not have a sacrotuberous ligament. The sciatic nerve lies just cranial and lateral to the sacrotuberous ligament. The internal[…]”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What procedure can be used at the time of castration and herniorrhaphy to prevent recurrence of bladder or prostate retroflexion?
Ductus deferopexy
You suspect a patient has perianal fistulas. What other conditions must you rule out how can this be done?
“Examination of the perineal area establishes the tentative diagnosis; however, histologic examination is necessary to rule out SCC (primary rule-out!), pythiosis, and other erosive conditions.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What kinds of bacteria (4) can you expect to isolate from a sample obtained from deep within a perianal fistula?
“E. coli, Staphylococcus pseudintermedius, α-hemolytic streptococci, and Proteus mirabilis.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the treatment goals and the three tenants of medical management of perianal fistula?
“Goal 1: Alleviate signs of tenesmus, dyschezia, hematochezia, constipation, diarrhea, and pain. Reduce defecation frequency. Obtained by induction phase treatment lasting 8 to 20 weeks.
Goal 2: Reduce diameter, depth, extent, and recurrence of fistulae. Obtained by maintenance therapy at the lowest effective dose every 24–72 hours; may be required for life”
“immunosuppression, hygiene, and dietary therapy”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Both cyclosporine and tacrolimus can be used for treatment of perianal fistula’s. The latter is typically used for mild cases or for chronic control after the former. What is the mechanism of action of these drugs?
They inhibit the phosphatase activity of calcineurin, thereby suppressing the activity of activated T-lymphocytes. 
What are the options for surgical management of perianal fistula‘s? When are they indicated?
Surgical treatment is only recommended for fistulae resistant to medical therapy or those associated with anal sacs.
Radical resection of disease skin, subcutaneous tissue, muscle and fascia, Followed by opposition of the rectum to skin using widely spaced sutures is typically performed. The remaining tissue is allowed to heal by second intention. Anal sacculectomy should also be performed if the anal sacs are involved. Chemical calterization with a strong iodine solution can be considered for mild cases.  cryotherapy is not recommended given the difficulty controlling the extension of tissue damage (nearly 50% of cases will develop anal strictures0
What are possible complications associated with the wide resection of perianal fistulas?
“• Fecal incontinence
• Flatulence
• Diarrhea
• Tenesmus
• Dyschezia
• Constipation
• Anal stenosis
• Recurrence”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the main differential diagnosis for a rectal prolapse? How are the two conditions differentiated?
Iliocolic intussusception
Introduce a finter of probe around the everted tissue. A rectal prolapse will have a fornix (finger cannot be advanced into the pelvic canal). A intussusseption will not.
What are two measures that can be taken to counteract tenezmus is a patient with a rectal prolapse?
Barium sulfate retention enema and epidural anesthesia
What muscles are involved in fecal continence (5)?
“Muscles involved in fecal continence include the internal anal sphincter, external anal sphincter, rectococcygeus, levator ani, and coccygeus muscles”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What two functions does fecal continence depend uppon?
Colonic reservoir function and sphincter control
List two possible causes of colonic reservoir and sphincter incontinence
“Reservoir Incontinence
• Diffuse colonic disease resulting in decreased distensibility
• Reduced colonic length after resection (e.g., two-thirds or more)
Sphincter Incontinence
• Rectal resection (>4 cm of terminal rectum)
• Inadequate cuff of terminal rectal mucosa (less than approximately 1.5 cm)
• Damage to the caudal rectal nerves
• Sacral spinal cord lesions of S1–S3 cord segments (L5 vertebral level in dogs and L6 in cats)
• Peripheral pudendal nerve damage
• Physical disruption of the external anal sphincter after:
• Anorectal trauma
• Rectal prolapse
• Severe perianal disease (e.g., inflammation, tumors)
• Surgical resection
• Resection of more than half the external anal sphincter”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What additional physical exam findings may you encounter in a patient presented with fecal incontinence?
Diminished anal sphincter tone
Distended and turgid or flaccid urinary bladder
Evidence of self-inflicted skin trauma due to paresthesia
Lumbosacral hyperesthesia (suggesting cauda equina syndrome
How can the anal reflex be tested?
 “A Foley catheter can be inflated in the rectum to determine if the dog has a normal anal reflex.”
“Manometry gives anal and colorectal pressure profiles and evaluates the degree of impairment of anorectal tone and internal and external anal sphincter function. The presence of an intact reflex arch may be determined more simply by inflating a Foley catheter in the rectum and observing the response.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the symptomatic medical treatment of fecal incontinence based upon?
“The goals of medical management are to reduce fecal water content and fecal bulk, slow transit time, and increase anal sphincter tone. Symptomatic medical management includes dietary change, pharmacologic therapy, and induced defecation. A low-residue diet (i.e., cottage cheese and rice) reduces fecal volume by up to 85% and lessens the frequency of defecation. Opioids (Box 18.72) promote segmental contractions, slowing bowel transit time and increasing water absorption. Enemas and rectal stimulation can promote colonic evacuation at appropriate times and help prevent inappropriate defecation.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the three described techniques to address fecal incontinence in the dog?
“fascial sling, silicone elastomer (Silastic sheeting #501-3), or dynamic myoplasty.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the elastomer technique utilized to improve anal function in patients with fecal incontinence
“Make 3- to 4-cm incisions on each side of the anus. Connect the incisions with a tunnel dorsal and ventral to the anus (dashed lines). (B) Direct the implant through the tunnels. (C) Secure the implant to the coccygeus muscle, pull it snug around a probe, and secure it to itself.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
You are presented with a patient who underwent a celiotomy three days ago. The suture line has the highest in the animal is eviscerated. How is the situation handled? Specifically refer to the existing sutures, wound edges and infection control measures
“entire suture line should be removed and replaced. Debridement of the wound edges is unnecessary and delays wound healing. The intestine should be closely inspected for viability and damaged sections resected if appropriate (see p. 440). The abdominal cavity should be lavaged copiously with warmed, sterile saline. Open abdominal drainage (OAD) (see p. 534) or suction drainage may be considered in animals with generalized peritonitis.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the most common complication associated with the use of non-absorbable suture material for the closure of abdominal incision?
Suture sinus formation
What is the prognosis for a patient with major abdominal wall evisceration following ovariohysterectomy who is promptly treated?
“Survival after major abdominal wall evisceration following ovariohysterectomy is high. The low mortality may be due to the fact that it most commonly occurs in young, otherwise healthy animals and is promptly recognized and treated.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What causes Zolliger-Ellison syndrome? What hormone is secreted in excess?
“Zollinger-Ellison syndrome is a condition caused by non–β-islet cell tumors, in which excess gastrin is secreted.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Sensitivity of ultrasonography for pancreatitis? How can it be improved? What’s the diagnostic of choice for pancreatitis in humans?
40 to 60%
Sensitivity can be improved with repeated scans every 24-48 hours as the apearence of the pancrease can change significantly.
Human standard: CT
How should Spec cPL and fPL tests be interpreted?
“Spec cPL and Spec fPL tests are sensitive enough to detect histologic pancreatitis that is not clinically important; therefore one should not blindly use these tests as a “litmus” test.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Endoscopic findings of a patient with Zollinger-Ellison syndrome
“On endoscopy, patients typically have esophagitis (because of profuse vomiting of acid) and duodenal ulcers or erosions. Duodenal biopsies typically have minimal inflammation. Gastric ulceration is much less common, but erosions and/or mucosal hypertrophy may be seen.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Zollinger-Ellison syndrome can be diagnosed based on a blood test. What is this test and how should the sample be obtained?
“Blood samples for serum gastrin analysis should be obtained after a 12-hour fast and before treatment with any antacid drug. Serum gastrin levels of animals with Zollinger-Ellison syndrome may exceed 1000 pg/mL.
”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
List five risk factors for the development of GDV
Pure breed large or a giant
Increased thoracic depth to width ratio
History of GDV in a first-degree relative
Feeding fewer meals per day
Eating rapidly
Aggressive or fearful temperament
Decreased food particle size
Increased hepatic gastric ligament length
Exercise or stress after a meal
Gastric foreign bodies increased the chance of GDV by 5 times (Battisti et al)
The role of splenectomy in the development of GDV remains controversial (studies disagree)

How can lactate be used to predict gastric necrosis as well as overall survival in patients with GDV?
De Papp et al, JAVMA 1999 - lactate more than 6.0 mmol/liter was 61% sensitive and 88% specific for gastric necrosis

Zacher LA et al, JAVMA 2010 - 90% of dogs with initial lactate of 9.0 mM/liter or less survived, versus 54% of dogs with initial lactate of 9.0 mmol/liter or more
What potential complication of long-standing extrahepatic biliary obstruction should be accounted for during pre-op planning of a patient who will undergo a cholecystectomy?
“Prolonged EHBO may cause vitamin K malabsorption, resulting in deficiencies of factors VII, IX, and X. Animals with clinical evidence of bleeding or increased mucosal bleeding time should receive vitamin K1 (subcutaneous [SC], not intravenous [IV] or intramuscular [IM]) for 24 to 48 hours before surgery (Box 21.1) or fresh whole blood (see p. 33).”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Why is antibiotic therapy recommended prior to operating on patients with extrahepatic biliary obstruction?
“Partial or complete biliary obstruction may allow ascending aerobic and anaerobic infection and subsequent bacteremia; therefore perioperative antibiotic therapy is indicated (see Chapter 9).”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the five most common bacterial agents isolated from the biliary tract of dogs? What antibiotics should be considered as part of intra-operative prophylaxis?
EEPPK
“Organisms most often isolated from biliary infection are Escherichia coli, Klebsiella spp., Enterobacter spp., Proteus spp., and Pseudomonas spp. Antibiotics excreted in active form into the bile, which are commonly used to treat biliary disease, include amoxicillin, cefazolin, and enrofloxacin ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Are gallbladder stones typically radiopaque or radiolucent? What is their clinical significance in dogs?
“however, most animals with gallstones do not have radiopaque stones, and even when stones are present, they are often incidental findings. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
How long after complete obstruction of the bile duct does it take until the gallbladder becomes distended? How about the extrahepatic and intrahepatic bile ducts
“With experimental bile duct ligation, the gallbladder becomes distended within 24 hours, and the extrahepatic bile ducts distend within 48 to 72 hours. Intrahepatic ducts take longer to dilate (approximately a week). Remember that dilation from a previous obstructive episode may not resolve; thus it may be difficult to discern whether the present dilation is due to recent or past disease.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
When is surgical treatment of EHBO recommended? (Time under medical management, clinical status). What techniques can be considered? Risks/success rate?
“The treatment of animals with EHBO secondary to pancreatitis consists of aggressive medical management. If clinical or laboratory improvement (not necessarily resolution) is not seen within 10 to 14 days of initiation of appropriate therapy, or if clinical deterioration occurs despite excellent medical therapy, cholecystoduodenostomy or cholecystojejunostomy may be considered despite the high morbidity/mortality associated with the procedure. In extremely ill patients with biliary obstruction that cannot undergo surgical exploration, temporary decompression of the gallbladder may be warranted using ultrasound-guided aspiration, choledochal tube (bile duct) stenting, or a Foley or self-retaining accordion catheter.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Choledochal tube stenting can be used in cases of reversible disease processes (i.e. pancreatitis, inflammatory lesions of the biliary tract or duodenum) to allow stabilization before definitive surgical treatment. Describe the technique for choledochal tube stenting. 
“After abdominal exploration, perform a longitudinal duodenotomy of the antimesenteric border of the duodenum over the major duodenal papilla. Flush the biliary tract as necessary, and treat primary disease (cholecystotomy, cholecystectomy, biliary duct repair). Pass a 5 to 10 cm fenestrated segment of red rubber catheter up the common bile duct via the duodenal papilla so that approximately one-half of the stent lies within the common bile duct and the other half resides within the duodenal lumen. Suture the stent to the submucosa of the duodenum aboral to the duodenal papilla using absorbable suture. Stents should be passed in the feces in 1 to 11 months or can be removed endoscopically if inflammation or infection is suspected.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Which technique has a lower morbidity/mortality - cholecystectomy or cholecystotomy?
“Cholecystotomy is rarely indicated to remove some choleliths (see p. 579), or when the contents of the gallbladder are inspissated and cannot be aspirated into a syringe. However, in almost all cases, cholecystectomy, which has a lower morbidity/mortality rate, is the preferred technique.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the technique for cholecystotomy
“Pack the area surrounding the gallbladder with sterile, moistened laparotomy sponges. Place stay sutures in the gallbladder to facilitate manipulation and reduce spillage. Make an incision in the fundus of the gallbladder (Fig. 21.3). Remove the gallbladder contents and submit for culture. Lavage the gallbladder with warmed, sterile saline. Catheterize the common bile duct via the cystic duct with a 3.5- or 5-Fr soft catheter, and flush it to ensure patency. Close the incision with a one- or two-layer inverting suture pattern using absorbable suture (3-0 to 5-0).”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the technique for cholecystectomy
“Expose the gallbladder and use Metzenbaum scissors to incise the visceral peritoneum along the junction of the gallbladder and the liver (Fig. 21.4A). Apply gentle traction to the gallbladder and use blunt dissection to free it from the liver. Free the cystic duct to its junction with the common bile duct. Be sure to identify the common bile duct and avoid damaging it during the procedure. If necessary, identify the common bile duct by placing a 3.5- or 5-Fr soft catheter into the duct via the duodenal papilla. Make a small enterotomy in the proximal duodenum, locate the duodenal papilla, and place a small red rubber tube into the common bile duct (see Fig. 21.4B). Flush the duct to ensure its patency. Clamp and double ligate the cystic duct and cystic artery (see Fig. 21.4C) with nonabsorbable suture (2-0 to 4-0). Sever the duct distal to the ligatures and remove the gallbladder. Submit a portion of the wall, plus bile, for culture if infection is suspected. Submit the remainder of the gallbladder for histologic analysis if indicated (for cholecystitis or neoplasia). Close the duodenal incision in a simple interrupted pattern with absorbable suture (2-0 to[…]”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What intra-operative step must always be taken prior to performing a cholecystectomy?
“Be sure that the common bile duct is patent before performing a cholecystectomy. The animal must have a pathway for biliary drainage into the intestinal tract.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the preferred method for treatment of bile duct rupture? Explain your reasoning based on the process of biliary tract healing
Studies have shown that even if just a small strip of the common bile duct remains intact, the duct regenerates. however, longitudinal tension on the suture line tends to lead to severe stenosis here do use of intraluminal tubes has been proposed and they also contribute to stenosis through foreign body reaction. Because of these uncertainties, drainage procedures such as cholecystojejunostomy , rather than direct repair of the common bioduct, is commonly performed. 
What is the reported mortality rate for dogs undergoing biliary surgery?
15 to 25%
List two negative post-operative prognostic indicators for dogs undergoing biliary surgery
Postoperative hypotension and dyspnea
List 5 Potential postoperative complications after cholecystectomy.
Generalized peritonitis, shock, sepsis, hypertension, hypokalemia, hypoproteinemia
What is the most common long-term complication of biliary diversion procedures such as cholecystojejunostomy? What are the potential long-term complications? 
Ascending cholangiohepatitis may occur, particularly if the stoma is too small and intestinal contents remain in the gallbladder lumen for prolonged periods. Long-term complications include cholangiohepatitis, recurrence of obstruction and chronic weight loss
What biochemistry abnormalities can you expect in a dog with EHBO?
Significantly elevated ALP and cholesterol, followed by ALT. Hyperbilirubinemia is typical in partial or complete obstruction and when ascending cholangitis occurs.
What is the most reliable laboratory indicator of biliary tract disease in cats?
Urinalysis is especially useful in cats because bilirubinuria is ALWAYS abnormal in this species, and it always presages hyperbilirubinemia
What are the first and the second most common causes of extrahepatic biliary obstruction in dogs?
1) pancreatitis
2) gallbladder mucocele
List three risk factors for the development of gallbladder Mucocele in dogs
1) Hyperadrenocorticism
2) hypothyroidism
3) excessive androgens
4) abnormal lipid metabolism
List 4 breeds predisposed to gallbladder disorders and Gallbladder mucocele
Shetland sheepdog
Cocker spaniel
Scottish terrier
Miniature schnauzer
Reported sensitivity and specificity of traditional ultrasound versus contrast enhanced ultrasound for the diagnosis of gallbladder wall rupture. 
In one study (Bargellini et al, Vet Rad Ultrasound 2016) Contrast enhanced ultrasound was 100% sensitive and specific for necrosis and rupture of the gallbladder.
Conventional ultrasonography is reportedly 75% sensitive and 81% specific
What type of suture material is recommended for the ligation of the cystic duct during cholecystectomy?
“Nonabsorbable monofilament suture should be used on the cystic duct during cholecystectomy (see p. 576).”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Where is rupture of the biliary tree most commonly observed after blunt force trauma?
“Trauma usually causes rupture of the common bile duct rather than the gallbladder. Ductal rupture probably occurs when a force is applied adjacent to the gallbladder sufficient to cause rapid emptying, combined with a shearing force on the duct.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What is the best diagnostic test to determine whether surgical intervention is necessary if bile peritonitis is a suspected?
“Comparing bilirubin concentrations in serum and abdominal fluid is 100% effective in diagnosing bile leakage. Bilious effusions have bilirubin concentrations greater (typically two times) than those found in serum.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
List 4 biochemistry abnormalities frequently observed in patients with bio peritonitis
“Serum biochemical abnormalities commonly found in dogs with bile peritonitis include hyperbilirubinemia, increased ALP, increased ALT, hypoalbuminemia, and hyponatremia.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
List some of the typical clinical findings (abnormalities) and recommended stabilization therapy for a patient with bile peritonitis prior to pursuing surgery
Anemia, requiring blood transfusion if PCV <20%
Hypoproteinemia, requiring plasma transfusion if severe
Dehydration and electrolyte imbalances, such as hyponatremia) requiring IV fluid therapy
Sepsis, requiring antibiotic therapy
Coagulation abnormalities due to vitamin K malabsorption or DIC, requiring vitamin K1 or fresh frozen plasma transfusion
How would you address a damaged hepatic duct?
“A damaged hepatic duct may be ligated because alternative routes for biliary drainage from a single liver lobe will develop.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Describe the local protective mechanism that prevents ascending bacterial infection from the intestines into the liver via the bile duct
“Normally, ascending infection is prevented by pressures at the major duodenal papilla, flushing of the ducts during bile flow, and the bacteriostatic action of bile salts. Kupffer cells, secretory immunoglobulin A, and mucus in the liver provide immunologic protection from portal blood as a source of infection.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What are the three most common clinical signs associated with cholecystitis?
“In the aforementioned study, the most common findings on physical examination included jaundice (56%), abdominal discomfort (56%), and fever (33%). Ascites was present on physical examination in 18%.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Suture filament structure and material recommended for oral surgery. Why?
“Monofilament suture material (i.e., 4-0 or 3-0 poliglecaprone 25, polyglyconate, polydioxanone, or polypropylene) minimizes wicking and tissue reaction. ”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
What does the oral mucosa heal faster than skin?
“The oral cavity and oropharyngeal mucosa heal more rapidly than skin because phagocytic activity (primarily monocytes rather than polymorphonuclear leukocytes) and epithelialization are more extensive and occur earlier in mucosa. An excellent mucosal blood supply, warmer temperatures, higher metabolic activity, and a higher mitotic rate contribute to rapid healing of mucosa. Apposed wounds reepithelialize within a few days, and defects heal by second intention.”
Excerpt From
Small Animal Surgery E-Book
Theresa Welch Fossum DVM, MS, PhD, Dipl ACVS
https://books.apple.com/us/book/small-animal-surgery-e-book/id1367916984
This material may be protected by copyright.
Reported survival rate, esophageal perforation rate and most common foreign body for surgically treated esophageal foreign bodies (Beer et al, JAVMA 5/2022)
(Rounded numbers)
Survival rate: 75%
Perforations observed at time of surgery: 35%
Most common foreign body associated with perforation: bone (but did not affect survival)
According to Cantatore et al.; what was the overall complication rate, overall recurrence rate and the two most common complications associated with the resection of rectal masses via the submucosal dissection approach?
What were the only two factors associated with the development of recurrence?
•Overall complication rate 29%
•Recurrence rate 21%
• Dyschezia (14% of cases), lasting median 24 days
• Tenezmus (12%); median 14 days
“none of the preoperative parameters and tumor characteristics was a predictor for recurrence or survival. Development of complications and incomplete margins on histopathology were the only factors associated with development of a recurrence. Development of recurrence was the only predictor significantly associated with the risk of tumor-related death.”
Cantatore, M, Jimeno Sandoval, JC, Das, S, et al. Submucosal resection via a transanal approach for treatment of epithelial rectal tumors – a multicenter study. Veterinary Surgery. 2022; 51( 3): 397- 408. doi:10.1111/vsu.13766
Is there a canine breed predisposed to colorectal tumors?
West Highland white terriers appeared to be overrepresented in this study, a finding that concurs with the results of previous studies.
Cantatore, M, Jimeno Sandoval, JC, Das, S, et al. Submucosal resection via a transanal approach for treatment of epithelial rectal tumors – a multicenter study. Veterinary Surgery. 2022; 51( 3): 397- 408. doi:10.1111/vsu.13766
Differences between Fredet-Ramstedt, Heineke-Mikulicz and Y-U pyloroplasties
Fredet-Ramstedt - partial thickness longitudinal incision through serosa and muscularis, allowed to remain open to relieve obstruction. Does not provide the option of inspecting the mucosa or obtaining biopsy samples.
Heineke-Mikulicz - full thickness longitudinal incision, closed transversely. Allows mucosa inspection and biopsy.
Y-U - full thickness Y-shaped incision closed as a U-shaped incision. Allows mass removal, mucosa, inspection, and biopsy.
Breed predisposed to gastroesophageal intussusception
“Although fewer than 30 cases of gastroesophageal intussusception have been reported, more than 75% were in dogs younger than 3 months of age, and more than 50% of cases occurred in German Shepherds.4”
Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.
Is gastro-esophageal intussusception a surgical emergency?
YES
A mortality rate of 95% was reported in a series of 22 cases described in 1984.111 However, more recent individual case reports document successful treatment and long-term survival in dogs diagnosed promptly and treated aggressively.32,76,79,126,193 Management of esophageal abnormalities and aspiration pneumonia is also critical for long-term survival. Whether megaesophagus resolves in affected dogs is unknown.”
Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.
Contrast the typical signalment for dogs with congenital versus acquired hypertrophic piloric gastropathy
Congenital obstructions - generally muscular - brachycephalic breeds younger than 1 year of age
Acquired obstructions - mucosal or a combination of mucosal and muscular - small-breed dogs (<10 kg) such as Shih Tzus, Maltese, and Lhasa Apsos
Reported more frequently in males than females
Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.
What are the five most common causes of gastric ulceration in dogs?
hepatic disease
neoplasia
renal disease
non-steroidal antiinflammatory
corticosteroid
Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.
Time from production to shedding of intestinal cells in dogs and cats
2 to 6 days
What is the purpose of the migrating myoelectric complexes observed in the small intestines in the period between meals?
To sweep residual and digested material throughout the G.I. tract
Cycle occurs every 1.5 to 2 hours, beginning with a latency phase, followed by roughly 15 minutes of fast rhythmic and fast contractions, extending from the pylorus to the colon.
The pylorus remains open (in contrast with the digestive/peristaltic phase)
Concerning intestinal absorption of nutrients, define the process of facilitated diffusion
Facilitated diffusion is a passive process by which molecules can cross the cell membrane using a protein which spans the distance across the membrane. The molecule can “slide” onto the protein, which undergoes structural changes to move it across the membrane following the concentration gradient. Being a passive diffusion process, it does not require energy (ATP)
Is the transport of water through the intestinal tract, active or passive? How much water is absorbed from intestinal contents in the jejunum versus the ilium?
Passive; follows the concentration gradient created by the transport of solutes across the cell membrane (which is an active process)
Jejunum > 50%
Ileum > 75%
What is the function of the hormone cholecystokinin and secretin?
Cholecystokinin: Produced by the small intestines in response to the presence of food. Responsible for the release of enzymes to begin the digestive process.
Secretin: stimulates the release of bicarbonate from the pancreas into the duodenum to neutralize acids deriving from the stomach.
Describe the synthesis and transport of chylomicrons
“Inside the enterocyte, fatty acids and monoglycerides are used to synthesize triglycerides, which are packaged with cholesterol, lipoproteins, and other lipids into chylomicrons. Chylomicrons undergo exocytosis and are transported into the lacteal that is associated with each villus. Chylomicron-rich lymph then drains into the lymphatic system, which flows into the blood”
Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.
Short bowel syndrome is raring, dogs, and cats. Approximately how much of the small intestines must be removed for this syndrome to occur? Is the risk higher with upper or lower small intestinal resections?
“In laboratory dogs with resection of either 50% of the proximal small bowel or the distal small bowel, proximal resection was better tolerated than distal resection. Twelve weeks after resection, body weight and serum cholesterol and albumin concentrations were lowest after distal resection. In addition, distal resection leads to persistent steatorrhea because the specific absorptive functions of the ileum cannot be assumed by the jejunum”
Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.
How does the prognosis for gastrointestinal foreign body, particularly linear foreign bodies, compare between dogs and cats?
“Prognosis after uncomplicated linear foreign body removal in cats is good.Intestinal perforations, which are uncommon in cats, are more likely to be associated with death after surgery. The prognosis for dogs is more guarded; the probability of peritonitis and death is nearly double that reported in cats. More than 30% of dogs have gross contamination of the abdomen from intestinal perforations, and more than 40% require intestinal resection and anastomosis. The need for multiple enterotomy incisions or extensive small bowel resection may be associated with higher mortality”
Excerpt From
Veterinary Surgery: Small Animal Expert Consult
Spencer A. Johnston VMD, DACVS & Karen M. Tobias DVM, MS, DACVS
https://books.apple.com/us/book/veterinary-surgery-small-animal-expert-consult/id1250368401
This material may be protected by copyright.
List 4 conditions or factors associated with increased incidence of colonic torsion
Exocrine pancreatic insufficiency
Lymphoplasmacytic enteritis
History of resection and anastomosis for foreign body obstruction
Previous gastropexy
Diagnose this condition with reference to what the white arrow is indicating.
Colonic torsion
The arrow points to the classic “pinching” characteristic of the radiographic diagnosis of this condition.
Three breeds that account for 80% of dogs diagnosed with colonic torsion
Labrador Retrievers, German Shepherd
Dogs, and Great Danes
Name three methods to increase the imaging diagnostic sensitivity for colonic torsion
CT scan
Barium enema
Pneumocolonogram
