Digestive Flashcards
Describe the splenic vasculature?
Celiac a.
- hepatic
- left gastric
- splenic
- pancreatic
- left gastroepiploic
- short gastic
Splenic v. ⇒ gastrosplenic v. ⇒ portal v.
What is the storage capacity of the spleen for rbc and platelets?
10-20% rbc mass
30% of platelet mass
What are the 3 major functions of the spleen?
- hematopoiesis: EMH fetal development, maturation of rbc, destruction of rbc, store iron (hemosiderin, ferritin). EMH dogs (uncommon cats)
- Reservior function: 3 pools - rapid (30 sec), intermidate (8min), slow (1hr)
- Immune: B-cells, T-cells, IgM, removal of IgG coated rbc/platelets.
What are the 4 mechanisms of generlized splenomegally?
inflammation, congestion, neoplasia/cell infiltration, cellular hyperplasia.
Difference between cat and dog spleen?
Dog: sinusoidal - combinaiton of direct arteriovenous AND areas where rbcs have transverse the red pulp before entering a sinus/venous side.
Cat: nonsinusoidal - open ended venous channels and perofrated endotheial channels = direct communication between arterial and venous vasculature.
Name causes of localized splenomegally - nine.
- Nodular hyperplasia: splenoma, fibrohistiocytic nodules (Cocker spaneils)
- Pseudotumor - benign lesion (plasma cells, histiocytes and lymphocytes)
- Hemangioma
- Haratoma - mature splenic tissue,, not normal structure
- Ascess - torsion, bacteremia, FB
- Cysts - humans
- Segemental infarction - poor profusion, hemobartenella
- Plaques - hemosiderosis, siderocalcific = hemosiderin, calcium, bilirubin
- Neoplasia: hemic vs. non-hemic
What are predisposing factors for splenic infarcts (9-10)?
Hypercoaguable = sx not recommended for seg. infarct due to risk
splenomegaly
cardiac, liver or renal disease
neoplasia
excessive corticosteroids
sepsis
splenic hematoma
vasculitis
On splenic US what is generally associated with the following:
Hypoechoic nodules
Diffuse hypoechogenicity
Hyperechoic nodules
Target lesions
multiple descreate lesions
Hypoechoic: lymphoid infiltration, infarction, necrosis
Diffuse hypoechoic: passive congestion, splenic torsion
Hyperechoic - nodular hyperplasia, neoplasia, fibrosis
Target lesions (hypoechoic rim): positive predicitve for malignacy
Multiple similar descreate lesion associated with maligancy
How does contrast enhanced (microbubble) US help define malignancy?
Malignant lesions have a different pattern than surrounding tissue. Accuracy similar to contrast MRI and CT
What changes are consistenty with malignancy on CT and MRI?
CT: lower Hounsfild units (pre and post contrast)
MRI: malignant hyperintense on T2 and postgadolinium
How does cytology compare to histopathology for splenic masses?
Variable but overall good for dx hematopoietic neoplasia and hyperplasia.
59% agreement, 29% partial agreement and 12% disagreement in one study
What stain can help ID cells of hmic origin?
Romanowsky
When dividing the spleen for a partial splenectomy, what are options?
TA stapler
2 clamps, cut inbetween and suture
CO2 laser
Ultrasonic cutting device
Biopolar electrosurigcal device
Ultrasongraphic appearence of splenic torsion?
Splenomegally, diffusely hypoechoic (also seen with necrosis and infarction)
6/7 dogs had hilar perivenous hyperechoic triangle
chronic may demonstrate gas shadowing
Absence of blood flow on color flow doppler US
What is the signalment for dogs with splenic torsion?
Large/giant deep chested dogs, MALES
Danes, St. Bernard, GSD, Irish setters
Poss. associated with spontaneous resolved GDV??
Percent of non-traumatic hemoabdomens with maligant cancer and what percent of these were HSA?
up to 80% malignant
of these 63-88% HSA
Percent of non-traumatic hemoabdomens with splenectomy that had arrythmias postop?
44%
What is the percent of arrhythmias associated with splenectomy for neoplasia and when are they more common?
35%
More common with anemia, hypotension, leukocytosis, and splenic mass rupture
What is it called when poor organ profusion occurs due to too tight of a closure of an abdominal hernia?
Abdominal compartment syndrome - associated with loss of domain.
What are the 4 priniciples of hernia repair?
- ensure viability of entrapped hernia contents
- release and return viable hernia contents into normal location
- remove reduntant hernia sac
- Provide tension free closure
Name 8 common sites for abdominal hernias
Paracostal, dorsal lateral, inguinal, femoral, perineal, cranial pubic ligament rutpure, umbilical, scrotal, ventral (subxyphoid)
How is the abdominal wall formed in embyro?
And what is the cause of an umbilical hernia?
Migration of the lateral, cephalic and caudal folds
Failure of the lateral folds to close
What passes through the umblicus?
umbilical blood vessels - (vein = faliciform lig)
Vitelline duct
stalk of the allantosis
What disease have been associated with umbilical hernias?
Fucosidosis = inherited neurovesical lysosomal storage disease
Ectodermal dysplasia
Cyrptorchidism
Other hernias and incomplete sternal fusion can co-exsist: ventral abdominal, diaphragmatic
Other midline defects and cardiac defects
What is gastroschisis and how is it different than an omphalcele?
It is a congential paramedian defect (omphalocele midline) exposing abominal contents.
What breed are at increased risk for umbilical hernia?
Airedale, basenji, Pekingese, pointers, weimerainers
Describe the boundries of the internal and external inguinal ring.
Internal: Medial rectus m., cr. internal abdominal oblique, lat/caudal: inguinal lig.
External: slit in apopneurosis of external abdominal oblique
Together form inguinal canal
What passes through the inguinal rings?
Gential branch of the gentifemoral a,v,n.
External pudendal vessels
Round lig (female), or spermatic cord
What is an inguinal heria that contains a gravid uterus?
Hysterocele
Three methods to repair a large inguinal hernia?
Own tissues
polyethylene mesh
cr. sartorius flap
Describe the femoral canal.
2 areas within the limits of the inguinal lig and pelvis.
- Muscular lacuna: Femoral n, and illiopsoas m.
- Vascular launa: femoral a, v, n and saphenous
Lacuna divided by the iliopectinal arch (iliac and transverse fascia = surrounds vasculature forming the femoral sheath)
What are risk factors for abdominal incision dehisence?
Increased intraabdominal pressure (pain), entrapped fat btwn edges of repair, inappropriate surture, infection, chronic steroid and poor postop care
What are methods to increase the strength of a prepubic tendon repair with mesh?
Mesh cuff with vertical mattress sutures
double layer mesh technique
What are factors associated with chronic incisional hernias
obesity, hypoproteinemia, cardiopulmonary complicaitons, absominal distension skin wound dehisence, and deep fasical infection
Local wound complcaitons most improtant
What are characteristerics of a desirable vascular muscle flap?
Avoid bulkiness
Avoid tension
Consistent vascular supply that is resistent to superfical trauma
Not result in significant loss of function
Be readily excessible
What are 3 major vascularized muscle flaps?
Cranial sartorius musle flap
External abdominal oblique myofascial flap
Latissimus dorsi
What is the origin and blood supply of the crainal sartorius flap?
What is it useful for?
iliac crest and lumbodorsal fascia
Branch of femoral a/v supplies proximal 1/3
Area covered: 30% caudal abdomen = transverse, 80% length btwn pubis and ribs
Used for prepubic, femoral and inguinal hernias
Delayed flap (distal blood supply) caudal abdominal repair in cats.
Describe the external abdominal oblique flap
Myofasical island flap (middle zone of the lateral abdominal wall)
Cr. branch of the cranial abdominal a. (hypogastric n and satellite v)
ventral, cranial to mid abdominal wall
10cm x 10cm area
Describe Marlex mesh.
Polypropylene mesh
inert
monofilament
woven
4-5mm fibrous tissue ingrowth by 6 months
Other meshes: Gore-tex (teflon) - permanent microporus, polygalctin 910 absorable
List biologic tissue grafts and their potential use?
SIS, dermis, pericardium
maybe useful for infected locations, avoids acute/chronic infection/inflammation
completely replaced with collagen in 4 months
Experimentally for abdominal wall defects, clinically for perneal hernias
What are three methods of mesh reconstruction? Which is better?
Onlay - more complications (_<_69% in people) increased infection, seroma, hematoma, extrusion = potentially due to more undermining/being superficial
Inlay - poor tissue interface
Underlay - best - lowest rate reherniation and wound complications = adhesions and enterocutaneous fisulas have been found in humans = need to use omentum
What are the surgical goals of abdominal herniorraphy?
Asepsis
tension free closure
use of strong tissue only
anatomaic closure
proper technical execution
What are the 4 major muscular and tendinous portions of the diaphram?
- central tendon: 21%
- Pars sternalis - xyphoid and 8th
- Pars lumbaris = left and right crus (R>L, lateral, intermediate and medial portions) - L3,L4 medial to psoas minor
- Parscostalis - 8-10th costal cart, 11 chostrochondral, 12th (ventral), 13 (dorsal)
What are the 3 opening of the diaphragm and what passes through?
Esophageal hiatus between 2 medial division of right crus: esophagus, blood supply, dorsal/vental vagal trunck
Aortic hiatus dorsally vertebral, L/R crucal tendons: aorta, azygos, hemiazygos, lumbar cysterna of thoracic duct
Caval foramen: within central tendon with fused adventia (only imobile of the 3): vena cava
What is the difference between cats and dogs phrenic nn?
Dogs: C5-7
Cats: C4-6, 5&6 most important
Described the embyrologic development of the diaphram
Transverse septum: central tendon
Dorsal esophageal mesentary (similar to transverse septum: crua, aortic and esophageal hiatus
Pleuroperitoneal folds: lateral portion that completes diaphram, myoblasts invade to form costal mm
What are 2 apporaches for a diaphragmatic hernia?
Ceiliotomy
9th lateral thoracotomy - need to know side, containdicated for bilateral or PPHD
WIth taumatic diaphragmatic hernias, what is the distrubution of the tears in dogs vs. cats?
Dogs: 40% circumferential, 40% radial, 20% combination
Cats: >59% cricumferential, 18%radial
What is the normal pleuroperitoneal pressure gradient?
normal 7-20 cmH20, during maximal inspiration PPG >100mmHg
What is the normal pressure gradient between the liver and vena cava?
Portal v: 8-12 mmHG
intrahepatic sinusoids: 3-4mmHg
Hepatic v and cd vena cava 0.5-1mmHg
What are contrast studies that can be used to diagnose a diaphragmatic hernia?
oral barium studies
pneumoperitoneography
positive contrast pleurography
portographycholecystography
angiography
What are alternative options of closure of a diaphragmatic defect if primary not possible?
Omentum
muscle
liver
fascia
mesh
silicon rubber sheeting
What is the Valsalva effect?
decreased venous reuturn from prolonged pulmonary expansion
What are the physiologic effects of compartment syndrome?
Decreased renal functoin
hypotension from decreased CO
Hypoxia reduced ventilation and lung compliance
Visceral hypoprofusion
acidosis
ICP
What are 2 types of congential diaphramatic hernias?
Pleuroperitoneal
Peritoneopericardial
What are compilcations of PPDH that are not commonly reported with traumatic hernia?
RHF, cardiac tamponade, hepatic cysts, gallbladder torsion/rupture, myelolipomatosis, chylothorax.
What are the bounderies of the epiploic foramen?
dorsally by the caudal vena cava, ventrally by the portal vein and hepatic artery, cranially by the caudate lobe of liver, and caudally by the celiac artery.
What are the 3 portions of the greater omentum?
Bursal (pars superficialis, pars profundus)
Splenic (gastrosplenic lig)
Veil
What are the size of the stomata in the peritoneum?
4-16 um mesotheilial process regulate size
What is the classification of peritoneal fluid?
Normal: cells <300, protein <3, colloid osmotic pressure 28mmHg
Transudate: cells <1500, protein <2.5g/dL
Modefied transudate: cells 1000-7000, protein 2.5-7.5
Exudate: cells>5000, protein >3
What are factors effecting particulate clearence via lymphatics from the abdomen?
Size
gravity
respirtatory and diaphragmatic movement
intestinal activity
Intraperitoneal pressure
What rate can the peritoneal cavity absorb fluid?
3-8% of body wt in Kg/ hour
What is normal intra-abdominal pressure?
2-7.5 cm H20
What are signs of increase IAP (20m h20) ?
increased HR, BP, bacterial translocation
decreased CO, GI blood flow
What are acute phase pro-inflammatory mediators?
What is an anti-inflammatory mediator?
Proinflammatory: TNF alpha, IL-8, IL-6, IL-1beta
Anti-inflam: IL-10
Macro produce TNF alpha, IL-1beta ~ recruit neutro, increase prosteglandins
Lymph = IL-6
mesothelial produce IL-8
Mast cell = histamine (+prosteglandin = vasdilation, increased permiability)
List adjuvants in peritonitis.
Gastic mucin: inhibits phagocytosis
Bile salts: alter cell adhesion, lyse rbc (increased Hb)
Hb: interferes with chemotaxis, phagocytosis, lymphcytic clearence
Barium
Peritoneal fluid: increased bacterial proliferation, slowed clearence
In dogs vs cats with primary peritonitis, what is the rate of monoclonal bacteria and what kind is present?
Dogs: 56% monoclonal, 80% gram +
Cats: 100% monoclonal, 60% gram +
Other organisms FIP, salmonella, chlamydia, clostridium, blasto, mycobacterium, citrobacter
What are indications of a retained surgical sponge on US and cytology?
US: hypoechomass with hyperechoic center
cyto: mononuclear cells with mulinucleat giant cells +/- fibers
Particles <15um can be removed by lymphatic circulation
What are causes of aseptic peritonitis?
chemical peritonitis
bile peritonitis
uropertoneum
peritoneal FB
starch granulamatous peritonitis
mechanical peritonitis
sclerosing encapsulating peritonitis
What has talcom powder in the abdomen been associated with?
Starch granulomatous peritonitis
granulomas, fecal fistula, sinus formation, intestinal obstruction, delayed wound healing
What has sclerosing encapsulating peritonitis been associated with?
Steatitis
fat necrosis
finerglass
bacterial peritonitis
chylous effusion
leishmaniasis
GI leakage is the cause of what % of secondary peritonitis in dogs and cats?
Dogs: 60%
Cat: 47%
What are possible risk factors after dehisence/peritonitis after GI surgery for incrased mortaliity?
longer duration of CS
linear FB
multiple intestinal procedures
How does alpha hemolysin facilitate E.coli and bacteriudes fragilis in septic peritonitis?
toxic to cells
decrease pH
lyse rbc
reduces viable leukocytes
presense increases patient mortality and increases likihood of recovery of these 2 species
What is the criteria for SIRIS in 1) dogs and 2) cats?
3 or more of these criteria
Dogs: Temp <100.4 >104, HR >120, R >20, WBC <5000 >18,000
Cats: Temp: >103.5, <100. HR >225 < 140. R >40. WBC <5000 >19500. Bands >5%
What is normal sonographic intestinal wall thickness?
Dogs:
<20kg: duodenum 4.7mm, jejunum 4.2mm
>20kg: 5.5mm, 4.7mm
Cats:
duodenum 2.7mm, jejunum 2.1mm
How does the accuracy of a single needle tap compare to a pertioneal catheter vs. a DPL for septic abdomen?
Needle: 43%
catheter: 83%
Diagnostic peritoneal lavage: 95%
How much fluid is instilled in diagnostic peritoneal lavage?
20-22ml/kg
How does serosal patching protect an R&A site and what % does it decrease mortality in patients with colonic perforation?
proteolytic activity degrades collagen and ECM
mortality decreased from 82% vs %56
What are advantages of open peritoneal drainage?
Increased efficiency removal bacteria
Improved metabolic state
Decreased abominal adhesions
Ease of inspection of abodmen
Unsuitable enviorment for bacteria
How do you diagnose uroabdomen?
Cre Fluid > 2.4x serum
Potssium fluid >1.4x serum
What is this?
Penrose sump drain
How is enteral feeding beneficial?
Good for enterocytes
Decreases bacterial translocation
Decreases mucosal permiabiliyt
Preserves secratory IgA conc in billary secreations
Maintains intestinal structure and function
What are benefical effects of low dose heprin therapy?
Improved clotting function
improved bacterial clearence
Decrased fibrin formation
Increased survivial
Decreased abodominal abcess formation
Dose 100-200 U/kg SC TID or QID
What is the mortality rate for septic peritonitis and what are indicators of a poor prognosis?
20-70%
Refracotry hypotenision
CV collapse
Resp. distress
DIC
pre-op elevated ALT and GGT
MODS
What is the formula for determining blood volume inthe abdomen from DPL?
(Venous PCV)(V in abodomen) = PCV fluid ((V in abdomen) + (V infuse))
What is the nerve supply and vascular supply to the muzzle?
nerve CN VII motor, CN V sensory
Facial a = lower lip and cheek
Infaorbital a = uper lip and cheek
What mm. make up the root of the tongue?
Styloglossis
Hypoglossus
genioglossus
Innervate by hypoglossal
What is the tube like structure under the tongue (made of mm, fat, cartilage)?
Lyssa
Name the gustatory and non-gustatory taste buds.
Gustatory: fungiform, vallate, foliate
Non-gustatory: filiform, conical
What are the 3 tonsils?
palatine
linguial - tongue
pharyngeal - nasopharx
Describe the 3 phases of deglutinion
1. Oropharyngeal
- oral = bolus CN5, 7, 12
- pharyngeal = base tongue to pharynx CN9, 10. phayrngeal constrictor mm→food aborally, palatal/pharyngeal mm. close nasopharynx, caudal epigastric reflexion & vocal folds block trachea.
-
pharyngosesophageal or cricopharyngeal = pharynx - circopharyngeal sphinter - eso, CN 9,10. Relax thyropharyngeaus and cricopharyngeaus.
2. Esophageal - primary parastolic wave +/- secondary wave
3. Gastroesophageal - muscularis relaxes in front of bolus
Reveiw mm. of tongue and pharynx
Borders of the parotid gland?
rostral: masseter m. TMJ
caudal: sternomastodideus
ventral: Mandibular SG
superfiical: parotidoauricularis, platysma m
What is the blood supply of the parotid gland, zygomatic gland, M SG, andsublingual SG?
Partoid: parotid (external carotid), superficial temporal v., great auricular v.
zygomatic: infraorbital a, deep facial v.
Mandibular: gladular br. of facial a., br. lingual v.
Sublingual:
- glandular br. facial a (monostomatic)
- sublingual br. of lingual a. (polystomatic - rostral to lingual n)
What mm. does the SL/Mandibular salivary duct run between?
Styloglossis
mylohyoideus
What are the minor salivary glands?
Buccal
labial
lingual
tonsillar
palatine
molar (cats - buccal, angle mandibile)
Functions salivary glands?
lubricate ingesta
pack food
thermoregulation
oral cavity clensing
buffering week acids
decrease bacteria
protect epithelium
Describe the pathway of saliva
intercalated ducts
intralobular ducts
interlobular ducts
lobular ducts
lobar ducts
major excretory ducts
Which salivary glands produce a more mucus secreation?
SL/zyomatic - mucus
parotid/mandibular -serous
A sliding bipedicle flap repair may be used to repair a congenital oronasal fistula. A, The dotted lines represent the mucoperiosteal incisions necessary to create two sliding flaps. B, The mucoperiosteum is elevated from the hard palate with the major palatine artery. C, The nasal mucosa and mucoperiosteum are apposed in two layers over the defect in the hard palate. D, Cross-sectional view of the repair.
A congenital oronasal fistula may be repaired with an overlapping flap technique. A, The dotted lines represent the incisions necessary to allow soft tissue closure. B and C, Elevate the mucoperiosteal flap and rotate it medially to cover the hard palate defect. Insert the edge of this flap between the hard palate and the mucoperiosteum on the opposite side of the defect. Secure the flaps in position with horizontal mattress sutures (inset). D, Complete the repair by apposing the incised edges of the cleft soft palate in three layers. Make lateral relief incisions (broken lines) to reduce tension on the repair.
A, Schematic drawing of a repair of a primary cleft palate involving the lip, premaxilla, and nostril. B, Create a flap from the nasal wall and suture it to a labial mucosal flap to separate the nasal cavity from the oral cavity. C, Repair the cleft lip with one or a series of Z-plasties: (1) Make incisions from A to B and a to c; (2) place a suture between A and a, and B and b, to transpose the flaps; (3) place additional sutures as needed.
Single-flap technique for fistula repair. A, Incise mucosa around the fistula to create the buccal flap (dashed line), then débride the fistula. B and C, Advance a buccal flap over the defect and suture into place. D and E, After débriding the fistula, create a hard palate rotational flap (dashed line) and rotate the mucoperiosteal hard palate flap over the defect. Suture the flap to surround the mucoperiosteum. F and G, To repair lesions at the junction of the hard and soft palates, débride the defect, then create and close the defect with a soft palate advancement flap (caudal dashed line).
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 insert). Cover this flap (bottom insert)with a rotational mucoperiosteal hard palate flap (palatal dashed).
A double-layer flap technique for fistula repair may be performed using a mucoperiosteal hard palate flap (palatal dashed line) and a buccal flap (buccal dashed lines). A and B, Create a flap from the mucoperiosteum of the hard palate (palatal and gingival dashed lines); rotate and suture to gingival margin. C and D, Cover it with a second flap created from the buccal mucosa (inset), then advance and suture over the first flap
Abdominal wall mm. anatomy
What is a direct vs. indirect inguinal hernia?
Describe scrotial hernia repair when castration not intended?
Repair of a scrotal hernia when castration is not intended. A, Proposed skin incision. B, Approach to the inguinal canal by blunt dissection. Evaluation of the hernia contents is made through an incision in the parietal vaginal tunic (hernial sac). The broken line indicates the direction of the abdominal incision if canal enlargement will facilitate reduction or resection of the hernia contents. C, After reduction, a transfixing ligature closes the enlarged vaginal process. D, Simple interrupted suture closure of the abdominal wall, the cranial part of the external inguinal ring, parietal vaginal tunic, and subcutaneous tissues.
Describe en bloc removal of an inguinal hernia?
En bloc technique for removal of the hernial sac and macerated hernia contents, thereby reducing contamination at the surgical site. A, Scrotal hernia with necrotic bowel segment. The broken line indicates the proposed skin incision for exposure. B, Ventral midline approach with ligation of the involved vessels, including isolation, transection, and Parker-Kerr oversewing of stumps leading to diseased intestine. Viable intestinal stumps are anastomosed. C, Reduction of oversewn intestine by minimal opening of the hernial ring; simultaneous cross-clamping of the hernial sac neck allows complete removal of the intact hernial sac and autolytic contents.
Describe how to repair a prepubic hernia with mesh?
Cuff mesh reinforcement of prepubic hernia. A, Ventral view showing damage and shredding of prepubic ligament. B, Interrupted vertical mattress suture fixation of mesh to the abdominal wall with interrupted sutures placed between reinforced prepubic tendon and pubic bone. C, Completed prepubic repair. D, Double-layer mesh technique to help prevent suture pull-out caused by weak hernia tissue edges
Describe the external oblique release and lateral sheath release.
Rectus advancement techniques demonstrating possible dissection planes through abdominal muscle fascia to release tension on a midline defect.
Describe the underlay mesh technique for hernia repair
Underlay mesh technique. A, Preplaced horizontal mattress suture catching omentum deep to the folded edge of the mesh. B, Rough edge of overlapped mesh faces away from abdominal viscera. C, Series of preplaced mattress sutures around the defect.
How can the abdomen be divided into quardants or 9 sections?
he right and left hypochondriac regions, the epigastric or xyphoid region, the umbilical region, the right and left lateral regions (including the flanks and paralumbar fossae), the right and left inguinal regions, and the pubic region
Structures of the oral cavity
General view of the oral cavity of the dog. 1, Vestibule; 2, canine tooth; 2a, philtrum; 3, hard palate; 4, soft palate; 5, tongue; 6, sublingual caruncle; 7, palatoglossal arch; 8, palatine tonsil; 9, frenulum
Frontal section of the head and neck, ventral aspect.
Antidrool cheiloplasty. A, Elevate the everted lip dorsally until it is taut when the dog’s mouth is opened maximally. B, Make a 2.5- to 3-cm horizontal, full-thickness incision through the maxillary skin at the site of tautness near the upper fourth premolar, with the caudal edge of the incision ending at a line parallel to the medial canthus and the caudal labial commissure. C, Remove a 2-mm wide strip of mucosa 2.5-cm long from the mucocutaneous junction of the lower lip, beginning 2 cm rostral to the commissure. D, Create 0.5- to 0.75-cm flaps. E, Evert the flaps through the skin incision, using a hemostat or stay sutures to grip the flap. F and G, Secure with vertical mattress sutures. Dashed line (F) represents the mucosal flap from the lower lip
What are phases of excretion of saliva?
Phase 1:
- acinus make saliva, (cells absorb Na, draws in water, Na rich)
Phase 2:
- intralobular duct epithelium: resorb Na, secreate bicarb and K
What does parasympathetic stimulation do to saliva production?
Increase
= blood vessel dialation and stimulation of cGMP ⇒ upregulate acinar cell activity
Via facial n. and mandibular nn.
sympathetic = minor inhibition after initial myoepithelial cell contraction
What are non-surgical disease of salivary tissue?
Sialoadenosis - treatment phenobarbital, limbic epilpsy
- esophageal abnormalities may also be present (sx, abx, and steriods do not help CS)
Sialoadenitis - terrier breeds predisposed
- possible link to hyperstimulation of the vagas n. = neural reflex syndrome
- may have similar cause as sialadenosis, some respond to phenobarb
Leakage from which salivary gland is most common?
Sublingual SG and duct
What dog breeds are predisposed to sialoceles?
poodles, GSD, Australian silky terriers, dachshunds
What are the 4 kinds of sialoceles?
Pharyngeal - caudodorsal or lateral pharynx, rostral to epiglotis = dsypnea
Zygomatic - orbital swelling, exopthalmous, elevated 3rd eyelid
Sublingual
Cervical
What is a stain that is specific for mucin?
Periodic acid-schiff
What is a differential dx for cervical mucocele?
Brachial cleft cyst - has true secretory lining
What is the recurrence rate of siaocele post sx removal?
5%
What are possible treatment strategies for sialoliths?
gland/duct removal
duct ligation
duct R & A
duct marsupialization into the mouth
incision over the stone +/- repair
Where are sialoliths most commonly found?
Parotid duct
What % of dogs and cats had regional lymph node involvement for sialoliths?
Cats: 39% regional, 16% distant
Dogs: 17% regional, 8% distant
What is the prognosis for salivary neoplasia?
MST 74-550d
correlated with stage, not grade
Describe approach to removal of the zyogmatic salivary gland
horizantal incision over dorsal aspect arch
Aponeurosis of masseter m. reflected ventrally
Orbital fascia reflected dorsally
remove portion of the arch
dissect gland - ligate br. infraorbital a. (malar a.)
do not repalce bone
Describe the approach to the parotid sialoadenctomy.
Incise over vertical ear canal (level fo the acoustic meatus) to angle mandible
incise platysma and parotidoauricularis m
ligate caudal auricualr v.
ligate duct
remove accessory parotid SG dorsal to the duct
What are the orgin and attachments of the major mm of mastication?
Masseter: zygomatic arch → lateral surface caudal body/ramus
Tempoalis: temporal skull → dorsal ramus
Pterygoideus: pterygoid, palatine, sphenoid bones → angular process
Digastricus (open): occiptal skull → ventral body
What is the blood supply of the mandible?
Maxillary a. → mandbiluar foramen → mandibular alveolar a. → mental foramen
Nervous supply of the mandible
Trigeminal n. → mandibular foramen → mandibular alveolar n. (sensory) →mental foramen →mental n. (incisors)
What are the 3 bones of the maxilla?
Maxilla: canine through molars
Incisive/premaxila: incisiors
Nasal: dorsal midline
What is the blood supply to teh maxilla?
Maxillary a → major palatine a. → caudal palatine foramen
Maxillary a. →maxiallary foramen → infraorbital a. → infraorbital foramen
What is the innervation of the maxilla?
CN 5 → maxillary n. →infraorbital canal
Muscles of the mandibule and blood supply
What are the 5 most common oral tumors? and what breeds are associated?
Melanoma: cockers, poodles, chows, goldens (small breeds)
SCC: older large breeds
FSA: middle to older large breeds: labs, goldens
OSA: medium to large breeds
Acanthomatous ameloblastoma: medium to large breeds
What are the 3 epulidides and their origins?
Acanthomatous: odontogenic epithelium
Fibroumatous eplis: peridontal lig.
Ossifying epulis: unknown
The last 2 can be cured with local excision, no bone removed
What percent of gingival bone tumors causes radiographic osteolysis?
60-80%
How does lymph node size relate to metastasis?
Inaccurate for metastatic disease
sens 70%, spec 51%
What are different types of mandibulectomeis?
What is the general prognosis for oral tumors?
70-90% 1 year survival with aggressive surgery
local recurrence <50% usually much less
What aspects of oral tumors are associated with a worse prognosis?
tumor type - melanoma and OSA worse bc malignant
Location - caudal location
incomplete excision: local reccurence complete ~20%, incomplete ~65%
Overall recurrence rates and survival best for SCC and ameloblastoma
What are the most common feline oral tumors?
SCC - 20-30% have nodal metastasis
What is the prognosis for feline SCC: mandibulaectomy +/- RT?
Mandibulectomy: progession free survival 56% 1yr, 49% 2yr
- 48% incomplete, 43% recurrence
RT alone MST 3 months
Mandibuletomy + RT = MST 14m 86% local recurrence
What are the 4 layers of the esophagus?
Adventitia
Muscularis - striated in dogs, caudal 1/3 smooth cats: arises from cricopharyngeus m and cricoesophageal tendon
Submucosa
Muscosa: stratified squamous epithelium
What composes the upper and low esophageal sphincters?
Upper: thyroipharyngeus, cricopharyngeus
Lower: thickended circum. striated mm, diaphragmatic crua, anlge meets stomach and the fold of the gastroesophageal mucosa
What is the blood supply of the esophagus?
Cerival: cranial and caudal thyroid aa.
Crainal 2/3 thoracic: bronchesophageal a.
Caudal: esophageal br arota or intercostal a
Terminal portion: left gastric a.
Venous: cervical external jugular vv. , thoracic azygous v.
What is the nervous supply of the esophagus?
branches of the vagus nn.
- paried pharyngeal esophageal nn
- recurrent laryngeal nn.
- paralaryngeal n.
- dorsa and ventral vagal trunks
How do you do a hemi-mandibulectomy?
Total hemimandibulectomy. A, Position the patient in ventral recumbency. B, Incise the mucosa 1 to 2 cm from the lesion. Incise the commissure to allow better exposure of the caudal mandible. Separate the mandibular symphysis and identify and transect (broken line) the muscles. C, Dissect and transect the lateral mandibular muscles and expose the temporomandibular joint. D, Dissect and transect the medial muscles of the mandible and identify the mandibular artery entering the mandibular foramen. Ligate the mandibular vessels, disarticulate, and remove the mandible. E, Appose the buccal and sublingual mucosa with approximating sutures
What are the transit times through the cervical esophagus?
Liquid in sternal: 2.54 cm/sec
Liquid in lateral: 7.23cm/sec
Kibble in sternal: 4.44cm/sec
Kibble in lateral: 8.92cm/sec
Reflex control of swollowing
What are potential reasons that the esophagus has a higher dehisence rate?
lack of serosa (elaboration of fibrin seal, source pluripotent mesothelial cells)
segmental blood supply
lack omentum
comstant motion
tension at site
What happens if disrupt segmental blood supply?
Can disrupt throacic if cervial and abdominal intact
disruption of cerival and thoracic = necrosis at inlet
most ischemic necrosis due to intramural vascular supply damage
What sx appraoches should be performed to reach the cervical, cr. thoracic and caudal esophagus?
- Cervical ventral midline
- Left 3-4 intercostal (brachiocephalic trunk and subclavian ventallly), right 3-5 intercosal (ventral trachea, ligate/retract azygous v.)
- left 7-9 (avoid vena cava and dorsal/ventral vagus nn)
How is the esophagus sutured and with what type of suture?
polydiaxonone or polyglyconate
2mm from edge and 2mm apart
single layer simple interrupted, continous (worse wound strength and apposition) and double layer interupted described. interrupted prefered and double layer seems standard.
How much esophagus can be removed in an R&A?
Clinically >3-5cm increased risk dehisence
Experimentally 20% of cervical esophagus or 50% thoracic esophagus
Describe how to do an a circimferential partial myotomy for esophageal R&A.
Outter longitudial layer incised 2-3cm cranial or caudal to R & A. If inner muscular incised = damage to submucosal vascualr plexus and necorsis
What was the mortality rate and complications with stapler and biofragmentable anastomsis ring devices?
No difference in complication rate or healing between the 2 devices
- 3% mortality rate - all biofrag
- 3% leak - all biofrag
11% stricture - all stapler
What are 2 types of esophageal patching?
inlay = partial circumferntial replacement
onlay = reinforce primary closure dt tension/decreased vascularity
What are materials that can be used for patching?
Omentum = mimize stricture formation → need to ligate right gastroepipolitc a.
Pericardium = increase strength without increased risk stricture
Local muscle flaps: sternohyoideus, longus coli (decrease stricture formation), free buccal mucosal graft, vascularized pedicle graft of internal/external intercostal mm (elevate periosteum), diaphram pedicale graft
Stomach, Jejunum (post mucosal stripping)
Lung
Porcine SIS, lyophilized dura mater, collagen coated vicryl mesh, expanded polytetrafluroehtylene patches
What are some options for esophageal substitution?
Cervical:
- Inverse tube skin graft: crainally based pedicle, inverted tube, sutured to distal esophagus, 2-3 weeks later cut pedicle. ALT: suture cranial and caudal esophagus to skin and 3-4 weeks later make tube.
- omocerival cutaneous island axial pattern flap - one stage tube skin graft
- possible complications; obstuction with hair, lack peristalsis and indistensibility
Thoracic:
- tubed inercostal musculopleural pedicle graft
- diaphragmatic pedicle graft
- tub lat dosi flap based on thoracoforal vessels
- gastric advancement and esophagogastric anastomosis
- isoperistalitc and antiperistaltic gastric tubes from greater curvature stomach (splenectomy required, consider pyloromyoplasty to enhance emptying since likely disrupt vagal innervation)
- jejunum (free microvascular graft)
- colon: more tolerent to ischemia than jejunum
What is the normal embryonic fate of the arches?
Ventral arotas = (1-2) external carotid aa, (3-4) common cartid aa.
Dorsal arotas = (1-2) internal carotid aa., (3-4) involution, (>4) desecending aorta
Left and right 1&2 = involution
Left 4th root/arch = adult arotic arch
Right 4th root = brachocephalic trunk
Right 4th arch = right subcalvaian a.
Left and right 5th = involuation
6th = pulmonary aa., left pulmonary retain connection to arota (left ductus arteriosus = ligamentum areriosum)
Left 7th intersegmental a = left subclavian a.
What are the most common vascular ring anomalies?
PRAA + left ligmentum ateriosum (C)
PRAA + aberrent left subcalvian= incomplete ring = (described with both left LA (2 structures) or right LA(single structure (G,F)
Double AA = both aortic arches persist, trachal stenosis (D)
Persistent right LA with normal left AA (mirror image PRAA) - cannot do left thorcotomy to correct (E)
Aberrant right subclavian a with normal left AA (incomplete ring) (H)
Persistent left cr. vena cava with non-elastic band around esophagus
What are vascular ring anomalies in cats?
PRAA with left LA
PRLA with left AA
PRAA with right LA and aberrent left SC
double AA
What is the general % of congenital abnormalities in dogs and cats/
Overall 20% - most not clinically sig.
Aberrant right SC most common, 6% - not clinically sig
95% clinical cases PRAA with left LA,
Ductus arteriosis patent in 10% with PRAA
Persistent left cr. vena cava in 45% - complicate approach
What breeds are predisposed to VRA?
Irish setters, GSD, breeds >15kg
siamese, persians
What is the prognosis for VRA?
No difference if operated early or late, survival at 2 weeks 92%, maybe good with some persistence of megaesphagus
Factors that effect prognosis include:
- degree of esophageal dialation
- severity of debilitation
- presence of aspiration pneumonia
- medical management before and after surgery
What breeds are effected by generalized megaesophagus and what is the suspected underlying cause?
Irish setters, GSD, danes, labs, shar-peis, newfies, mini schanauzers, fox terriers
defect in vagal afferent innervation
74% dead by 1 year age
What is a possible sx treatment for congenital megaesphagus?
Esophagodiaphargmatic cardioplasty - pulls caudally on esophagus during respiration
Good outcome in 50%
What is a esophageal duplication cyst?
Often fluctuant mass cranioventral cervial region
2 muscle layers and epithelium
Can excise with good outcome
Where do esophageal foreign bodies generally lodge for bones, fish hooks and dental chews?
Bones: heart- diaphram 65-79%, heart base 11-39%
Fish hooks: pharyngeal esophag 34%, thoracic inlet 11%, heart bse 30%, heat-diaphram 5%
Dental chews 74% in distal esophagus
What are reasons for surgical removal of an esophageal forgein body?
Inability to remove endoscopy: 63% remove with endo, 29% pushed into stomach, 8% need sx
If contrast migrates away (if compartamentalized around perf can med mang)
pleural effusion
pneumothroax
pneumomediastinum
sepsis
endoscopic risk laceration
What is the prognosis for penetrating forgein bodies?
Mortality rate 26% with stick penetration
acute penetrating FB worse that oropharyngeal pentration
What percent of post-anesthesia esophageal strictures are single or multiple?
Single 62-75%
Multiple 38%
What is the difference in force between bougienage or ballon dialation?
Bougies - longitudinal shear
Balloon - radial force
What is the incidence of perforation for ballon dialtion and bougienage of the esophageal strictures?
Balloon = 3.6-11%
Bougienage 3.6%
What are options for treatment of esophageal strictures?
bougienage
balloon dialation
steroids (oral/intralesional) - no evidence
Esophageal stents
Surgery: esophagoplasty - transverse closure, esophageal R&A, patch esophagoplasty - (incise longitudinally and inlay sternohyoid, incostal, diaphram, or pericardium), esophageal substitution
What is the prognosis for general treatment of esophageal stricutre?
Good: 71-88%
Surgery associated with high rate of stricture recurrence and dehisence
What are 3 types of esophageal diverticulums?
Pulsion: outpouching of mucosa through tunica muscularis
traction: full thickness deviation (assumed from inflammation of adjacent organ)
Epiphrenic: between heart base and diverticulum
What percent of canines with an esophageal diverticulum had a bronchoesophageal fistula?
50%
If impacted
→ obstruction
→chronic esophagitis → stricture
→ peridiverticulits → adhesion/fistula
→ rutpure
What breeds tend to get an esophageal diverticula?
Small breeds
Cairn terriers (propensity for FB??), mini poodles, Parson Russel terriers
How are esophageal diverticula treated?
Small diverticula: conserative, guel diet
Large: lateral thoracotomy
Excision via stapler, partial resection and in-lay, complete R&A, esophageal substitution
PX: good for simple, guarded for extensive repair
How is a congenital esophageal fistulae caused?
Incomplete separation of the tracheobronchial tree from the digestive tract
aquired due to FB
Bronchoesophageal > tracheoesophageal
What is the most common lung lobe effected by esopheal fistula?
Right caudal (66%)
Others: right cranial, middle, accessory and left caudal
What is cricopharyngeal dysplasia?
Swallowing disorder characterized cricopharyngeal achalasia or asynchrony
Usually congenital and dx by 12 m, older may be aquired
What cricopharygeal achalasia? asynchrony?
Achalasia: upper esophageal sphincter fails to open during cricopharyngeal phase
Asynchrony: incoordination between contraction of pharyngeal contractor mm. and relaxion of upper sphincter
What is the treatment for cricopharyngeal dysphagia?
CP myotomy or myectomy
Ventral or lateral approach
Place orogastric tube, remove 2cm of m. → place metal clips for post-op fluroscopy
Also described with thyropharyngeal myotomy
Descrine the origin, insertion and innervation of the criopharyngeal m.?
Singel muscle
Origin: lateral surface of cricoid cartilage → spreads over esophagus → attaches on other side.
Innervation: CN9 (glossopharyngeal n.) and pharyngeal br. of vagus n.
Blood supply: cranial thyroid a.
How do you differeniate pharyngeal dysplasia from criocopharyngeal dysphagia?
barium study for CP dyplasia
Lateral fluoroscopic view of barium swallow. Barium appears black on fluoroscopy. Row 1, Normal dog; 1A, liquid barium bolus in the pharynx; 1B, closure of the epiglottis at the onset of swallowing; 1C, opening of the cranial esophageal sphincter; and 1D, closure of the cranial esophageal sphincter and reopening of the epiglottis. Row 2, Dog with cricopharyngeal achalasia; 2A, liquid barium bolus in the pharynx; 2B, contraction of pharynx without opening of the cranial esophageal sphincter; 2C, opening of cranial esophageal sphincter and reopening of the epiglottis; and 2D, closure of the cranial esophageal sphincter.
Lateral approach to the pharynx
What is the prognosis for CP dysplasia?
Complete resolution CS in 49% dogs, another immediate resolution in 13/14 dogs
Poorer px: failure to transect all bands, incorrect diagnosis, concurrent pharyngeal/esophageal dysfunction, structural problems (fibrosis), esophageal stricture, function disease, masticatory myosti, myasthenia gravis, aspiration pneumonia, malnutrition
What the most common esophageal tumors in dogs and cats?
Dogs: SCC leiomyosarcoma, ODA, FSA < sarcoma, leiomyoma, plasmacytoma
- most common site caudal esophagus
Cats: SCC
- most common site cranial thoracic esophagus
What parasite is associated with esophageal nodules in dogs?
Spirocerca lupi
Dogs definative host: ingest coprophagous beatle → larvea gastric mucosa to aa. → thoracic aorta wall to caudal esophagus
What tumors are associated with Spirocerce lupi?
OSA, FSA, undiffereniated sarcoma
What are clinical signs assocaited with maligant spirocera tumors?
HO 38%, none with benign had
Lower Hct, higher WBC and platelets
Malignant masses larger (6x7cm) and more likely to cause bronchia displacement (52% vs 17%)
Diagnostic findings consistent with spirocera?
Microcytic anemia
Rads: masses, mets, HO
Caudal thoracic spondylitis and aortic mineralization
What % of esophageal tumors have mets at diagnosis?
50%
Name important structures of the stomach.
4 parts: cardia, fundus, body, distal 1/3 (pylorus (double mm layer) , pyloric antrum, pyloric canal)
Cardiac notch: btwn cardia and blind outpouching of stomach
Angular incisure: where papliary process of liver lies
Describe the blood supply of the stomach
Celiac a.
- splenic → pancreatic and L. gastroepipolic (greater curve, anastoms with R. GE) , short gastric aa.
- Hepatic → br. to liver and gallbladder
-
Right gastic → pylorus
-
Gastroduodenal
- Right gastroepipolic
- Cr. Pancreaaticoduodenal
-
Gastroduodenal
-
Right gastic → pylorus
- Left gastric → lesser curvature
Portal v.
- Gastroduodenal → Right, gastric, R. gastroepiploic
- Gastrosplenic → Left gastric, Left gastroepipolic
What is the innervation to the stomach?
Parasymphathetic → vagus n. → ventral vagal truck (pylorus, liver, lesser curve), dorsal vagal (lesser curve, ventral wall → then follows celiac and cr. mesenteric a.)
Sympathetic → celiac plexus (arise from celiacomesenteric plexus and follow gastric br celiac a)
Describe the gastric layers.
Serosa
Muscularis
- Circular = cardia to pylorus except fundus, Longitudinal = esophagus to pylorus on greater curvature (not lesser, ventral and dorsal body), Fundus and body = inner oblique fibers
Submucosa
Mucosa
- Columnar surface epithelium, Glandular lamina propria and Lamina muscularis mucosa
Describe the locations and gland types of the stomach.
3 types: cardiac, pyloric and gastric.
Cardiac (cardia and antrum): serous
Pyloric (pylorus and gastric body): mucus
Gastric (fundus and body):
- Parietal
- Cheif
- Mucous neck
- endocrine
Describe the functions of the gastric cell types:
Parietal (oxyntic):
- maintain gastric acid pH (pump H+ into lumen), allows activation of gastric enzymes food breakdown
- produce intrinsic factor: mucoprotein that binds to B12 to allow absorption SI
Cheif: pepsinogen → converts to pepsin (protein breakdown)
Mucous: mucous to protect glandular cells from acid and enzymes
Endocrine: gastrin, histamine, serotonin
Describe the different mechanisms of healing in the stomach
Superfical: epithelial migration
Mucosa erosions: epithelial regeneration
Injury to submucosal = ulcer
- short-term fibrous protein synthesis > wound contration and scar resorbed
- long-term: exuberant fibrotic repair with permanant scar
Incisional healing:
- similar to other areas: inflammation, debridment, repair, maturation
- In contrast other tissue, GI smooth muscle contribute to collagen production
What is the downside to withholding food 8-12 hours prior to sx?
Decreased gastric pH = increased GE reflux (57% ortho procedures, 14% clinically noted. In post-anesthesia esophageal dysfunction, only 46% clincially noted)
Doesn’t reliably decrease contents
May help to feed small amounts q3hr
What anesthestic agents may be beneficial for gastic sx?
Anticholingerics - decreased gastic secreations
H2 blockers
AVOID nitrous = rapid diffusion into gas filled organs
Transection of which lig. may help with exposure of the stomach?
Hepatogastric
hepatodoudenal
What is a disadvantage of flush that is warmer than normal body temp?
Increase body temp
vasodilation/hypotension
increased adhesion formation
Describe paracostal approch to stomach
In rare instances when exposure of only a portion of the stomach is required, a paracostal approach may be used. A paracostal approach is achieved by making a curved incision approximately 2 cm caudal to the last rib. The underlying muscle layers, including the external and internal abdominal oblique and transversus abdominis muscles, are split longitudinally along the direction of the muscle fibers. When ventral extension of the incision is necessary for visualization, the rectus abdominis muscle may require transection. Closure is achieved with a simple continuous pattern in each muscle layer
What is the half life of PDS, maxon and monocryl in gastric fluid?
PDS: 12d - only suture tensile strength effected, @ 2pH 10x shorter than at 7.4
Monocyrl 15d
Maxon 75d
Polyglycolide and poly l-lactidie coglycolide had inital delays in linear absorption = coating
What staples have been reported for stomach closure? And pexy?
TA, GIA, skin stapler (oversew of line recommended)
Pexy: GIA or skin staples (with skin staples tensile strength similar to belt loop)
What are methods of determining viabillity of the stomach?
Subjective (85% accurate): Wall thickness, perastalsis, serosal capillary profusion, serosal color
- incise seromuscular layer = evaluate a. blood supply
Objective:
Fluorescein dye injection: 58% accurate
Lazer flow doppler = to subjective
Scintigraphy: 79%
List types of gastropexy.
Incisional - 4-5cm, parralel or perpendicular to long axis
Belt-loop
Circumcostal - double or single hinged
Incorporating - no inicison in stomach
Tube gastropexy - highest recurrence rate 5-29%
gastrocolopexy - nonabsorbable suture, scarified/not incised
Lap/Lap-assited
Endoscopically assicsted
Grid approach - mini-lap
What is a Fredet-Ramstedt myotomy? Disadvantages?
Longitudinal seromuscular inision through the pylorus
Does not allow: visualization gastric mucosa, relieve restrictions of the mucosa/submucosa, provide full thickness biopsy
What is a Heineke-Mikuliez pyloroplasty?
What is a Y-U pylorplasty?
What are indictions for a bilroth 1?
Neoplasia confined to pyloric region
Ulceration of outflow track
Pyloric hypertrophy
Describe technique for Bilroth 1.
Pylorectomy with end to end gastroduoenostomy
No difference in leakage between a single and double layer closure
What is the prognosis of a bilroth 1?
75% survive 2 weeks, but only 33.3% alive at 3 months
Complications:
- 63% hypoalbuminemia
- 58% anemia
- Decreased survial with preop weight loss
What is a bilroth 2?
Partial gastrectomy with gastrojejunal anastomosis
(duodenum and gastrotomy close, jejunum anastomsed to the side)
poor results
What is the classification system for hiatal hernia?
I: sliding hernia: intermittent movement GE junction into thoax, congenital common (Shar peis and English bulldogs). Aquired = BAS or upper resp. disease
II:Paraesophageal: GE junct normal postion, fundus herniated
III: Elements both I and II
IV: herniation of other organs besides stomach
A, Normal anatomy of the junction of the esophagus and stomach. B, Type I sliding hiatal hernia in which the gastroesophageal junction has moved cranial to the diaphragm. C, Type II paraesophageal hernia occurs when a portion of the stomach moves into the caudal thorax through the hiatus adjacent to the esophagus. D, Type III hiatal hernia combines the movement of the gastroesophageal junction into the thorax as well as movement of a portion of the stomach into the thorax adjacent to the esophagus. E, Gastroesophageal intussusception.
What are the goals of medical management of hiatal hernia?
- Reduce gastric acid: H2 blockers and proton pump inhibtors
- Esophageal mucosas protection: sucralfate (polyaluminum sucrose - binds denuded mucosa)
- Increase gastric emptying: prokinetics, low fat diet in elevated postion (if megaesophogus)
- Enhance LES tone: prokinetics
How many hiatal hernias improve with medical management? And how long should it be attempted prior to surgery?
53% (8/15)
recommend for 30 days
How is hiatal hernia treated surgically?
- Phenoplasty = Phernicoesophageal lig. transection OR horizantal mattress sutures with nylon 2-0. Alone = reherniation
- Esophapexy: left esophagus to diaphram
- Gastropexy: left body wall (increases LES tone)
Before performing need to transect the hepatogastic lig. and place orogastric tube
What is the nervous supply to the small intestine?
splanchnic n. via celiac and cranial mesenteric plexus
vagas
Abdominal autonomic nervous system, left lateral view. The cranial mesenteric ganglion (34) is located on the sides and caudal surface of the cranial mesenteric artery. 1, Stomach; 2, ventral trunk of vagus nerve; 3, esophagus; 4, dorsal trunk of vagus nerve; 4a, celiac branch of dorsal vagal trunk; 5, aorta; 6, intercostal artery and nerve; 7, ramus communicans; 8, sympathetic trunk; 9, celiac artery; 10, quadratus lumborum; 11, major splanchnic nerve; 12, cranial mesenteric artery; 13, lumbar sympathetic ganglion at L2; 14, minor splanchnic nerve; 15, tendon of left crus of diaphragm; 16, psoas major; 17, lumbar splanchnic nerve; 18, transected psoas minor; 19, deep circumflex iliac artery; 20, caudal mesenteric artery; 21, left hypogastric nerve; 22, caudal mesenteric plexus; 23, caudal mesenteric ganglion; 24, testicular artery and vein; 25, descending colon; 26, cranial ureteral artery; 27, jejunum; 28, caudal vena cava; 29, greater omentum; 30, renal artery and plexus; adrenal gland; 32, common trunk for caudal phrenic and cranial abdominal vein; 33, adrenal plexus; 34, celiac and cranial mesenteric ganglia and plexus.
What are the electrolyte changes associated with a proximal duodenal obstruction?
hypochloremia, hypokalemic, metabolic alkalosis
not proximal = metabolic acidosis from loss of bicarb
Arterial supply to the small intestines
Venous supply to SI
The mesentery gathers and attaches to the abdominal wall opposite the second lumbar vertebra by a short peritoneal attachment known as the root of the mesentery (1) through which the proximal portion of the cranial mesenteric artery passes.
The small intestines are structurally composed of four layers: the mucosa, submucosa, muscularis, and serosa. The cells at the base of the villi are dividing, undifferentiated epithelial cells that are primarily involved in fluid secretion. The cells mature and differentiate into immature enterocytes as they pass up the crypt.
What is a modefied Gambee stitch?
Emerges at the mucosa/submucoas junct = can help mucosal eversion
What are the three stapling techniques for SI R&A?
Triangulating end to end anastomosis with TA 30 staplers (3 cartridges - attached pic)
Inverting end to end with EEA stapler
Side to side (function end to end) using GIA
End-to-end anastomosis using a triangulation technique and a skin stapler. Place three stay sutures to appose the ends of the intestine and divide the circumference into three equal parts. Apply tension between two sutures. Center the skin stapler between the two segments, then apply staples with gentle pressure approximately 2 to 3 mm apart. Apposed edges of the intestinal wall be slightly evected
For an inverting end-to-end anastomosis, use an EEA stapler and a transverse stapler. Insert the stapler cartridge into the intestinal lumen through an enterotomy 3 to 4 cm from the transection site. Insert the anvil into the other intestinal end. Tie purse-string sutures securely around the shaft of the stapler. After completing the anastomosis, close the enterotomy with sutures or a transverse stapler
Colonic orifaces?
Colonic blood supply
Cr. mesenteric a.
-
common trunk
- Middle colic - desending colon
- Right colonic - transverse colon
- Illeocololic
- Cd pancreaticoduodenal
- Jejunal aa.
- Ileal aa.
Caudal mesenteric a.
- cr. rectal
- left coloic (anastomosis with middle colic)
Left colic → caudal mesenteric (middle colic), (ileocolic (right colic and cecal)) → portal v.
Describe electorlyte and water transport in colon
Electrical gradient: basolateral Na/K pump, apical brush border K selective channels
Na/k pump (elecrogenic), Na/H 1-3 or Cl/HCO3 (electroneutral
Aquaporins: Colon absorbs 1.5L fluid/d
What is a Parker-Kerr pattern?
Cushing pattern over a clump, then oversewn with Lembert
What is a Furniss clamp?
Auto-suturing for purse string placement
How to discern primary from seconday megacolon in cats
How to manage idopathic megacolon
how to manage seconday megacolon
What is the vascular supply to rectum/anus?
Vaculature: intrapelvic
- Cranial rectal a. (majority)
- Internal iliac → Internal pudenal a
- Middle rectal
- Caudal rectal
- Cats = intraplevic adequately supplied by middle and cd. Rectal (NOT dogs, need cr. Rectal)
General anatomy of rectum
- Retroperitoneal portion: lacks serosa – implications for healing
- Anal canal – 1cm length
- Columbar zone
- Intermediate zone = anocutaneous line
- Cutaneous zones
- Internal zone
- Anal glands
- Anal sacs - ivaginations
- External zone
- Circumanal glands (perianal, hepatoid)
- Internal zone
- Anal glands (tubular swear glands): columnar and intermediate zones
- Glycoproteins (alpha-l-furctose) = viscoelastic properties mucus
Describe the ventral approach to the rectum
- Pubic symphysiotomy
- Pubic or pubic and ischial osteotomy increses exposure
- Ideally at least 2cm normal tissue should be removed on either side
Describe dorsal approach to the rectum
- U shaped incision between anus and tail (extend to tubur ischium)
- Rectococcygeus mm, dorsal rectum and sphinctes are visible
- Rectoccygeus mm transected at attachement on coccygeal vertebra
- Blunt dissect between the levator ani and sphintermm. And levator ani transected if needed
Describe rectal pull though
- Rectal pull through, transanal pull through
- If incison made at anal-cutaneous junct = incontence and removal of anal sacs, start 1.5cm internally to avoid this
Describe Lateral approach
- Resection of a rectal diverticulum, rectocutaneous fistula, repair laceration of rectum
- Curvilinear perianal incision – tail base to ischium
- Dissect between external anal sphincter and levator ani
What is a anogenital cleft?
- Have cloaca, ventral aspect anus incomplete and forms dorasal part of cleft
- Males often have hypospadias
What are methods of treatment of rectal prolapse?
-
Reduce prolapse/edema: saline, lubricants, 50% dextrose, liver yeast cell derivative, systemic furosemide
- Apply purse string 3-5d (time to tx underlying cause)
- Dicyclomine anticholinergic-antispasmatic
- Retention enema with hydrocortisone or mesalamine
- Rectal resection and anastomosis – place tube and cut full thickness (see Fig 94-12).
- Multiple recurrence = colopexy
- No difference between incisional colopexy and scarifcation with 2 rows of 5 or 6 simple interrupted sutures
Perineal anatomy
- Levator ani: attach 7th cd vertebra, external anal sphincter
- Iliocaudalis
- Pubocaudalis – inserts perineal body
- Coccygeus: originates spine of ishium, attach transvers process 2-5th lumber vertebra
- External anal sphincter: 3rd cd vertebra and levator ani
- Internal obturator
- Sacrotuberous lig: ischiatic tuberosity to sacrum and 1st cd vertebra
- Ischiorectal fossa: laterally levator ani/coccygeus, dorsal/lat superficial gluteal, dorsal external anal sphincter and ventral internal obturator, constrictor vulae female, retractor penis make
Blood supply:
- Internal pudendal: courses over internal obturator m.
Surgical preparation of the perineal area. Incision A, traditional perineal herniorrhaphy; incision B, superficial gluteal transposition; 1, purse-string suture in the anus; 2, iliac crest; 3, greater trochanter of the femur; and 4, ischial tuberosity. The incision for the internal obturator muscle transposition should extend 2 to 3 cm ventral to the ischial tuberosity.
uture placement for traditional herniorrhaphy (caudolateral view). 1, external anal sphincter; 2, coccygeal muscle; 3, superficial gluteal muscle; 4, ischial tuberosity; 5, internal obturator muscle elevated from ischial table; and 6, retractor penis muscle.
emitendinosus muscle transposition for repair of recurrent bilateral perineal hernias in a Yorkshire terrier (also pictured in Figure 94-30). Previous bilateral internal obturator transpositions and subsequent unilateral prosthetic mesh placement had failed. A, The circumference of the semitendinosus muscle is isolated, taking care to avoid injury to the caudal gluteal artery and vein (visible at the tip of the electrocautery unit). B, The muscle is transected distal to the midbody and freed with gentle dissection as it is reflected dorsally. Lateral tendinous attachments can be incised to improve mobility. C, The muscle has been sutured to external anal sphincter medially, levator ani and coccygeus remnants dorsally, and superficial gluteal muscle laterally. D, Final appearance 1 day after surgery. The dog maintained a rounded appearance of the dorsal perineal region because of obesity and thickness of the transposed muscles; however, the hernias did not reoccur.
Anatomic arrangement of the liver lobes and extrahepatic biliary tract. A, Diaphragmatic aspect of the liver. B, Visceral aspect of the liver. C, Liver lobes, gallbladder, and hepatic ducts, visceral aspect
Describe the flow of bile.
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Canaliculi
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interlobular ducts
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Lobar ducts (inside parachyma) = Hepatic ducts (2-8 ducts)
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Common bile duct (where 1st hepatic joins cystic)
- Sphincter of Oddi (CBD enters duodenum)
- Duodenum (major duodenal papilla)
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Common bile duct (where 1st hepatic joins cystic)
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Lobar ducts (inside parachyma) = Hepatic ducts (2-8 ducts)
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interlobular ducts
List the tributaries to the portal v. (caudal to cr)
Cr. Mesenteric vessels
Cd mesenteric vessels
Splenic
Gastroduodenal
Hepatic veins
Describe the embyronic deveolopment of the liver
vitelline vessels = hepatic sinusoids, cr. right becomes cd. vena cava in liver, right and left cd segements anastomos to become portal v.
umbilical v = hepatic sinusoids
cardinal = anastomse with vitelline to make cd vena cava, right suprecardinal = azygos, left supracardinal = hemiazygos
Embryology of liver development. 1, Sinus venosus; 2, superior cardinal vein; 3, inferior cardinal vein; 4, left common cardinal vein. 5, right umbilical vein; 6, liver; 7, anastomosis between the left and right omphalomesenteric vein; 8, right umbilical vein (prehepatic); 9, left umbilical vein; 10, right omphalomesenteric vein; 11, umbilical vein (unpaired); 12, inferior vena cava; 13, ductus venosus; 14, portal vein; and 15, splenic vein.
Types of PSS
Types of portosystemic shunts in dogs and cats. A, Portal vein to caudal vena cava. B, Portal vein to azygos vein. C, Left gastric vein to caudal vena cava. D, Splenic vein to caudal vena cava. E, Left gastric, cranial mesenteric, caudal mesenteric, or gastroduodenal vein to caudal vena cava. F, Combinations of the above.
What are the methods for scintigraphic ID of shunts and what are the limitations?
Dx: arrives sooner and in higher conc. than expected to heart, PSS shunt fract >60-80%, 52% cats
Transcolonic: (99mTcPertechnetate) shunt fraction <15% normal, false + if injected too caudal, heart visible 8-14sec, higer dose = isolate for 16-24hr
Transsplemic: (99mTcO4-) lower shunt fraction, 100% sens/spec for PSS, in heart 2-4 sec, uptake poor with portal hypertension, cleared 30 min
Increased shunt fraction with: PSS, aquired PSS, and AV malformations. Doesn’t distinguish intra from extra or intra, single from multiple and MVD from normal…at least reliably for the first 2.
Transsplenic scintigraphy. A, Extrahepatic portocaval shunt in a Labrador retriever. Blood flow from the spleen enters the heart at its caudodorsal aspect. B, Portoazygos shunt in a Yorkshire terrier. Blood flow from the spleen enters the heart at its craniodorsal aspect. C, Multiple acquired shunts in a Chihuahua. Blood flow travels caudally from the spleen before entering the caudal vena cava
Intravascular hepatic shunt - left division
Venous dilatation at junct. left hepatic v. patent ductus venosus and left phrenic v = ampulla
Usually ligate shunt (bwteen papillary process and L lat lobe before enters L hepatic v. ) OR heptatic v.
If shunt can’t be ID then left portal v.
The left hepatic vein (LHV) enters the left side of the caudal vena cava (CVC) just cranial to the diaphragm. The central hepatic vein termination is indicated with an asterisk. B, The space between the CVC and LHV is gradually enlarged with right-angle forceps, which are advanced in a dorsolateral position
Intravascular hepatic shunt - right division
In dogs, the portal vein (PV) bifurcates approximately 1 cm distal to the termination of the gastroduodenal vein (GDV). The left hepatic vein (asterisk) is much smaller in this dog with a right intrahepatic portosystemic shunt
Ligate portal v. (see above) or intravascular technique
If can’t directly disect, then can do indirect suture passage
Indirect suture passage for ligation of a right intrahepatic portocaval shunt. In a dog with a right-sided shunt, the portal vein would be much larger than the left
Intravascular approach Portal venotomy
Need total inflow occlusion = pre/post hepatic cd. vena cava, thoracic aorta, and portal v./hepatic a. through epiploic foramen
- mean arterial P = 30mmHg, mean CVC pressure = 25mmHg
Intravascular repair of an intrahepatic portocaval shunt through a portal venotomy. A, The portal vein is exposed and the dilated prehepatic segment (star) is identified. B, After inflow occlusion, a venotomy is performed. The edges of the portal venotomy are retracted with stay sutures (arrows), and the shunt ostium is identified. C, A suture (5-0 prolene) is passed across the shunt ostium and though pledgets. D, The venotomy is closed with a simple continuous pattern, and inflow occlusion is released. The attenuating suture is subsequently tightened. CVC, Caudal vena cava; LL, left lateral; PV, portal vein; QU, quadrate; R, rumel; RHV, right hepatic vein; RL, right lateral; RM, right medial; S, shunt.
Intravascular approach transcaval approach
Intravascular repair of an intrahepatic portocaval shunt, diaphragmatic view. The suture is passed through extraluminal and intraluminal Dacron pledgets in a mattress pattern
Bile duct anatomy near major duodenal papilla
How to place pharyngostomy tube
Nerve damage, hemorrahge, if not caudal dorsal enough interfers with epiglotis = aspiration, cough, knking, dyspnea, etc.
Indictor for oral disease
Percutaneous tube esophagostomy. A, Stiff guide tube placed in midesophagus. B, Catheter passed through the skin and into the tube. C, Forceps placed in the catheter hub and advanced into the guide tube. D, Forceps pulls large feeding tube out through skin. E, The tip of a large feeding tube is sutured to tip of esophagostomy tube. F, The large feeding tube pulls esophagostomy tube into the mouth. A stylet is placed in the esophagostomy tube. G, The esophagostomy tube is withdrawn until it can be redirected distally. H, The tip of the esophagostomy tube is advanced to the distal esophagus.
Percutaneous esophagostomy using an Eld applicator. A, The Eld applicator is placed in the esophagus, and the trocar is advanced through a small skin incision. B, The feeding tube is sutured to the eyelet of the Eld trocar. C, After the feeding tube is pulled into the oral cavity, a stylet helps to redirect the feeding tube into the esophagus
What is this?
Feeding tube applicator
Placement of percutaneous endoscopic gastrostomy tube. A, An over-the-needle catheter is placed through the skin and into the air-distended stomach. B, A suture threaded through the catheter is grasped by endoscopic forceps and pulled out through the mouth (C). D, An over-the-needle catheter is threaded onto the suture, which is tied to the gastrostomy tube (E) and subsequently pulled into the stomach and out the gastric and body wall. F–G, The tube is pulled through the skin and secured with a flange. The mushroom-tipped end of the gastrostomy tube should press snugly against the gastric mucosa.
Tube-assisted percutaneous nonendoscopic gastrostomy. The angled tube is inserted through the esophagus into the stomach at a level caudal to the last rib. Extending the patient’s head over the end of the table facilitates palpation of the tube through the abdominal wall. A, The flared end of the tube in the stomach is pressed against the left abdominal wall, displacing other intra-abdominal organs. B, A needle is passed through the skin into the flared end of the tube, and a strand of heavy suture or wire is passed through the needle into the stomach and advanced out of the mouth. The remainder of the placement is the same as that for a percutaneous endoscopic gastrostomy tube.
Percutaneous nonendoscopic gastrostomy with an Eld device. A, The device consists of a cannula with a handle and a trocar that is passed through the cannula after it is properly positioned. B, The device is advanced through the esophagus and into the stomach so it is beyond the last rib. The trocar is pushed through the cannula until the tip exits the skin, and a suture is tied onto the tip (inset). C, The trocar is retracted into the cannula (inset), and the device and attached suture are withdrawn through the animal’s mouth. The remainder of the placement is the same as that for a percutaneous endoscopic gastrostomy tube.
Low-profile gastrostomy device (arrowhead). Pressure on the obturator (solid arrow) elongates the mushroom tip for placement through the gastrocutaneous fistula (open arrow). The mushroom tip regains its conformation when the obturator is removed
Enterostomy tube placement. A, An antimesenteric incision is made through serosa and muscularis, and the feeding tube is advanced through a mucosal perforation at the aboral end of the incision. B, Serosa and muscularis are sutured with an appositional pattern over the tube, and a purse-string or mattress suture is placed around the tube at its orad seromuscular exit site.
Needle-assisted enterostomy. A, A needle is passed obliquely through the center of a purse-string suture, creating a subserosal tunnel in the antimesenteric intestinal wall. B, A feeding tube is passed through the needle and advanced 20 to 30 cm aborally. The needle is removed, and the purse string is tied
Examples of commercially available clamps designed for use with linear external skeletal fixation systems. A, Kirschner-Ehmer clamp; single and double clamps (IMEX Veterinary Inc., Longview, TX). B, SK clamp; single and double (IMEX Veterinary Inc.). C, Securos external skeletal fixator clamp (Securos, Sturbridge, MA). D, Titan external skeletal clamp (Securos). Black arrow, position for transfixation pin; white arrow, position for connecting bar
What is this?
Robinson sling
Other wierd slings = schroeder thomas
