Upper GIT Surgery Flashcards
(109 cards)
1
Q
Which slaivary glands do dogs and cats have respectively?
A
» Dogs; 4 pairs = parotid, mandibular, sublingual, zygomatic
» Cats; 5 pairs = parotid, mandibular, sublingual, zygomatic and molar
2
Q
List some non surgical salivary gland diseases?
A
- Hypersialism (inc prod saliva)
- Sialoadenosis (bilat, non painful enlargement of mand salivary gland)
- Necrotising Sialoadenitis (rare)
3
Q
describe Hypersialism?
A
– Increased production of saliva
* Salivation in cats can be a sign of dental disease
* Ptyalism can be a sign of portosystemic shunt (more commonly cat)
4
Q
Describe Sialoadenosis
A
- Clinical signs: retching, gulping, hypersialism, weight loss
- No histopathological changes
- Treatment = oral phenobarbitone
- Most common in terriers
5
Q
Describe Necrotising Sialoadenitis
A
- Acute, painful enlargement of mandibular glands
- Clinical signs: dysphagia, vomiting, anorexia and weight loss
- Changes on histopathology
- Surgical removal of gland ineffective
- Some cases respond to phenobarbitone
6
Q
List some Surgical Salivary gland diseases
A
- Salivary mucocoele
- Sialoliths
- Neoplasia
7
Q
Describe Salivary mucocoele
A
- Saliva in subcut tissues
- Lined with inflammatory tissue (no epithelial lining)
- Traumatic
8
Q
How are mucocoeles classified?
A
cervical, sublingual (ranula), pharyngeal, zygomatic
9
Q
Presentation and CLS of Salivary mucocele ?
A
- Young animals; Poodles, Dachshunds, Australian Terriers
- Painless, fluctuant swelling
- Usually unilateral
- Often asymptomatic; ptyalism & dysphagia
10
Q
What signs with ygomatic mucocoele?
A
exophthalmos, strabismus, swelling in conjunctival fornix
11
Q
Signs of Pharyngeal Mucocoele?
A
; less common; dysphagia and dyspnoea
12
Q
What is sublingual mucocoele also called?
A
Ranula
13
Q
Diagnosis of Salivary Mucocoele ?
A
- Presentation & clinical signs
- Paracentesis – viscous, golden/brown or blood tinged fluid, low cell count
» Determining side of origination difficult
* Dorsal recumbency
* Sialography - useful but difficult to perform
14
Q
Tx for Mucocoele?
A
- Sialoadenectomy -> resection of gland & duct (excision of mucocoele not rq)
- Aspiration & drainage-> ineffective -> fibrosis & infection
- Marsupialisation -> ONLY for sublingual/ranula! -> relies on formation of permanent fistula
15
Q
Describe sialoliths?
A
- Diagnosis - CT
- Treatment – sialoadenectomy, duct ligation, duct resection&anastomosis, marsupialisation, removal and primary repair
16
Q
Neoplasia of salivary gland?
A
- Adenocarcinomas, mandibular gland most affected
- Locally invasive, met to LNs
- Unilateral, firm, painless swelling, halitosis, dysphagia
- Diagnosis - CT most useful + biopsies (+LN)
- Treatment – wide excision; difficult due to location/invasiveness
+/- post op radiation therapy
17
Q
Trauma of salivary gland?
A
- Most heal without treatment
- Cutaneous fistulas/mucocoeles can develop
- Treatment – sialoadenectomy and drainage of dead space
18
Q
Sialodenectomy recurrence rate & complications ?
A
- Recurrence low = 5% (failure to remove all tissue)
- Complications:
Seroma
Damage to neurovascular structures
19
Q
Step by step salivary gland removal?
A
20
Q
What are the four layers fo. the oesophagus?
A
- Mucosa
- Submucosa (holding layer for sutures)
- Muscularis
> entirely striated in dogs
>striated cranial to the heart, then smooth in cats - Adventitia (not serosa)
21
Q
What four locations does the oedophagus narrow?
A
- pharyngo-oesophageal sphincter
- gastro-oesophageal sphincter
- thoracic inlet
- base of the heart
22
Q
What sections of the oesophagus are there?
A
» Cervical
* Dorsal to trachea initially then deviates to the left
before thoracic inlet
» Thoracic
» Abdominal
23
Q
Why does the oesophagus not heal very well?
A
High rate of dehiscence; lack of
serosa & omentum, constant
movement
24
Q
What medical conditions of the oesophagus to be aware of?
A
▪ Oesophagitis
▪ Conditions causing megaoesophagus
* Myasthenia Gravis
* Dysautonomia in cats
25
What are thre 4 Surgical approaches to the oesophagus?
- Cervical
- Cranial thoracic
- Caudal thoracic
- Caudal oesophagus & stomach
26
Location of cervical approach?
Ventral midline incision (larynx to manubrium)
» can extend via median sternotomy
27
Locations for cranial thoracic approach?
: left 3rd/4th or right 3rd/4th/5th intercostal thoracotomy
28
Location fo caudal thoracic approach?
: left 7th, 8th or 9th intercostal thoracotomy
29
Location fo Caudal oesophagus & stomach approach?
cranial celiotomy & diaphragmatic incision or caudal median sternotomy
30
How do we suture the Oesophagus
* Monofilament, absorbable (PDS), round bodied needle
* 2mm from cut edge; 2-3mm apart
* Incorporate submucosa
* Two appositional layers
* Or single appositional full thickness
31
Describe Oesophagotomy/ gostomy?
* Foreign body removal, traumatic ruptures
* Isolate surgical site with swabs
* Occlude lumen cranially and caudally
* Stab incision, extended longitudinally as necessary
* Single or double layer interrupted or continuous sutures
incorporating submucosa
32
Oesophagela resection reasons?
Congenital ob structions, trauma, neoplasia, stricture
33
How would we resect oesophagus portion?
* Resections > 3-5 cm → risk dehiscence due to tension
* Circumferential partial myotomy may reduce tension
34
How do we anastamose the free ends after resection?
* Anastomosis may be performed with a circular EEAstapler
* Simple interrupted sutures
* +/- gastrostomy tube (bypass for healing)
35
What is Oesophageal patching?
* Toreinforce sutures/oesophagus
* Placed over incision site
36
What could we use for oesophageal patching
* sterno-thyroid muscle (cervical oesophagus),
* pericardium or intercostal muscles (thoracic oesophagus)
* omentum or diaphragm (distal oesophagus)
37
Describe prevalence/predisps to oesophageal FBs in dogs and cats
* Common in dogs; rare in cats
* Young Terriers; Bones
* Caudal thoracic oesophagus between heart & diaphragm (65-79%)
* pharyngeal opening, thoracic inlet, base of the heart
* Cat; needles & hooks
* Hooks; pharynx or base of the heart
38
CLS of Oesophageal FB?
* few hours to several months
* regurgitation minutes after eating, coughing, salivation, restlessness, lethargy, inappetence
39
What can perforation due. toFB cause?
pneumo-mediastinum, pneumothorax, mediastinitis, pleuritis, pyothorax, mediastinal
abscess or broncho-oesophageal fistula
* lethargy, tachypnoea, pyrexia, cough
40
Diagnostics for Oesophageal FB?
* Owner may report ingestion
* Radiographs: Neck & Thorax
* Endoscopy
41
Tx of choice for FB?
Endoscopy
* Retrieval orally
* Push into stomach & leave to digest
* +/- gastrostomy tube
* Post op rad to look for evidence of oesophageal tear
## Footnote
Otherwise surgery
42
Post op from oesophageal surgery we would give ...
* analgesia
* antacids
* omeprazole
* sucralfate
* anti-spasmodic (metoclopramide)
* antibiotics
* feeding tube
43
Describe use fo feeding tube post op?
* Must use gastrotomy tube
* PEG tube-endoscopically placed
* Surgically placed on left side
* Care with early removal
44
Complication after oesophageal FB removal ?
* Leakage
* Pleural effusion
* Stricture-can occur after endoscopic removal
45
What are some other siurgical diseases of the Oesophagus ?
- Vascular ring anomalies
- Oesophageal diverticula
- Oesophageal fistula
- Cricopharyngeal Achalasia (myotomy curative)
- Oesophageal neoplasia
46
Describe oesophageal neoplasia
* very rare, < 0.5% of tumours
* squamous cell carcinoma, leiomyosarcoma, fibrosarcoma and osteosarcoma
* Paraoesophageal tumours: thymic, heart base, thyroid
* Prognosis is poor for cure or palliation
47
How do we usually see GI issues present?
PE -> mass/fb, thickened intestines, organ displacement
Biochem & haem -> concurrent dx
Electrolyte and acid-base abnormalities
48
What electrolyte & acid base abnoramlities might we see?
* disease oral to major duodenal papilla
➢ hypochloraemic metabolic alkalosis (loss of chloride and hydrogen)
* disease aboral to major duodenal papilla
➢ hypokalaemic, hyponatraemic metabolic acidosis
49
Diagnostics for GI surgery?
50
What are some anaesthetic considerations for GI surgery?
* Fluid, electrolyte and acid-base disturbances
* Starve: 12-18 hours for elective procedure;
* Rapid induction; patients may vomit;
* Avoid Nitrous oxide
* Epidural/multimodal analgesia
* Minimize heat loss hot air warmers/water blankets
51
How to mitigate regurg/vomit ?
* stomach tubing may be necessary;
* well fitting/cuffed ET tube;
* suction available if regurgitation
52
How long should we starve paediatric patient or LI surgery patients?
* 4-6 hours for paediatric;
* 48 hours for large intestinal surgery
53
What are the bacteria found in diff parts of the gut?
» Intestinal tract bacteria: lots, E.coli and Clostridium
» Stomach bacteria: low numbers as acidic, Helicobacter spp.
» Colon bacteria: coliform and anaerobic
* Colonic surgery greatest risk of post-op peritonitis
54
When should we use Antibiotics for GI surgery?
➢ Clean-contaminated procedures; > than 90 min
➢ Contaminated procedures
➢ Dirty procedures (septic peritonitis, intestinal ischaemia, strangulating obstruction, colorectal surgery)
➢ Animals at increased risk (distant infection, prior irradiation of the surgical site, elderly, debilitated,
immunocompromised)
➢ Severe mucosal insult (haemorrhagic diarrhoea, pyrexia, leucocytosis/leucopaenia)
55
What AB would we use for GI sx?
» Broad-spectrum antibiotic: (cefuroxime or potentiated amoxicillin)
» 20mg/kg IV, q2 hrs during surgery, then q6-8 hrs for up to 24 hrs (longer if spillage)
» Administered 30-60 min prior to incision (at induction)
56
What sx has highest risk of spilling & therefore post of infection?
Colonic surgery
57
How can we minimise contamination in GI sx?
* **Exteriorise** & isolate with moistened lap swabs
➢ Layering swabs
➢ Cannot exteriorise stomach, proximal duodenum, descending colon
* **Milk** intestinal contents **away** & occlude lumen before incising
➢ **Stay** **sutures** stomach, decrease spillage
* Gloves, drapes, instruments changed for abdominal closure
* Copious lavage
58
Why do we need to handle GI gently?
* Handling→desiccation and abrasion
* →increased inflammation, adhesions, ileus, peritoneal fluid production
59
HOW do we handle GI tissue ?
* Stay sutures, atraumatic instruments (DeBakey forceps), fingers
* Cover tissues with moistened swabs
* Clamping intestines; assistant fingers=least traumatic technique
* Atraumatic intestinal forceps (Doyen); closed to one ‘click’
60
describe use fo sutures in GI tissue?
» Staples: decrease surgical time, blood loss, tissue manipulation & contamination
➢ limited availability and costly
61
what are the parts of the stomach?
Cardia, fundus, body (greater and lesser curvature), Pylorus (antrum & sphincter)
62
# Va
Vascularisation of Stomach?
* lesser curvature gastric arteries
* greater curvature gastroepiploic arteries fundus/body short gastric arteries
63
Describe the omentum?
» *Omentum*:
* angiogenic & growth factors
* increases serosal surface
* neutrophils, macrophages and lymphocytes
* Omental *bursa* – potential space for stomach to enter
64
Periop considerations of gastric sx?
- V+ -> dehydration, electrolyte inbalance
- Reflux -> premed with H2 blckers?
- Regurg -> pharynx suctioned before extubate
- Stomach distention -> Preoxygenate to dec hypoventilation/hypoxia & AVOID Nitrous oxide
- Pain -> inhibits motility, catcholamine release -> inhibits local perf -> prokinetics? analgesia!
- Nutritional support -> + motility (asap)
- Periop AB
65
Gastric risk of leakage usually within ..... hrs?
72-96 hours
66
Gastric closure options?
1. Single layer closure -> apposiitonal continuous (start and en in normal tissue)
OR
2. Two layer closure -> better
67
Describe your two layer closure
* appositional continuous mucosa/submucosal; appositional or inverting serosa/muscularis
* appositional continuous suture incorporating all layers; continuous inverting
MUST incorporate submucosa
68
What sutures would you use in the stomach closure?
» Absorbable synthetic monofilament sutures (PDS) 3-0
» Taper-cut or reverse cutting needle, swaged
» Stapling devices can be used
69
Describe Gastrotomy for FB removal or biopsy
1. Isolate stomach; stay sutures/lap swabs
2. Stab incision; centre of the body, between vessels
3. Extend with Metzenbaum scissors
4. Suction gastric fluid
5. Foreign body removal (spoon or forceps)
➢ minimize glove contamination
6. Close as described
7. Lavage abdomen
8. Swab count
9.Change gloves/instruments
10.Close abdomen routinely
70
When would we perform Partial Gastrectomy? ( & invagination)
» necrosis, ulceration/perforation, neoplasia in greater curvature or fundus
71
detail the partial gastrectomy?
* Excise necrotic tissue
* Atraumatic forceps - Doyen
* Ligate vessels & resect omentum
* Facilitated by surgical staplers
72
Detail gastric invagination?
* Continuous inverting pattern
* Suture bites in healthy tissue ~ 0.5-1cm apart
* Appose healthy serosal surfaces
➢ necrotic tissue inverted into lumen
* Second inverting layer if possible
73
How can we assess tissue viability ?
» Ischaemic necrosis; secondary to dilatation, obstruction or strangulation
* Re-assess tissue 10-15 min after derotation or removal of foreign body
74
Ischaemia is more subtle - what to assess?
➢ colour
➢ thickness of tissue on palpation
➢ texture
➢ peristalsis
➢ vessel pulsation
➢ bleeding on cut surface
75
Describe GDV
» acute gastric dilation, acute gastric dilatation-volvulus and chronic gastric volvulus
» Increased intra-gastric pressure →cardiovascular, respiratory & gastrointestinal systems
» Exact cause unknown,
76
What are some risk factors to GDV?
* Large- and giant-breed dogs.
* First-degree relative had a GDV
* Large thoracic depth to width ratio
* Underweight dogs
* Increasing age
* Splenomegaly and splenectomy
* Behaviours/conditions that promote aerophagia
* Eating from a raised food dish
* Stress
77
CLS of GDV?
* acute onset retching, regurgitation or vomiting
* hypersalivation
* agitation
* palpable abdominal distension
* Shock; tachypnea, dyspnea, tachycardia, pale, dry, mucous membranes, lethargy
78
Diagnosis of GDV?
* right-lateral radiography
* “double bubble”, ‘reverse C’ = compartmentalisation
* +/-pneumoperitoneum, if rupture
79
What diagnostics for GDV?
» Collect biochemistry, haematology, electrolytes and (blood gas)
» ECG; VPCs/ventricular tachycardia
- Radiography
80
Describe the pathophysiology of GDV
» gastric distension → compression of caudal vena cava & portal vein
» Lack of venous return → decrease in cardiac output
» →poor perfusion and oxygen delivery to tissues
81
What are some further consequences of the pathophys of GDV?
» Cardiac arrhythmias due to myocardial ischemia
» ↓ gastric perfusion →serosal hemorrhage and oedema→necrosis & perforation → peritonitis
» Infarction of splenic arteries and thrombosis of splenic veins→splenic necrosis
82
what about effect of stomach pressing on diaphragm?
» hypercapnia (respiratory acidosis) and hypoxaemia, further decreases oxygen delivery to poorly perfused tissues
83
What are the 4 principles of GDV surgery
1. Aggressive Stabilisation of circulatory collapse/shock
2. Reposition the stomach
3. Remove devitalised tissue
4. Gastropexy to prevent recurrence
84
How do we stabilise the shock at first?
1. Two large bore cannulas placed into cephalic (or jugular) veins
2. Crystalloids bolus given at shock rate (45-90ml/kg) or colloids at 10-20ml/kg
➢ careful monitoring for response to treatment
3. Decompress the stomach
85
How would you decompress the stomach ?
a) pass orogastric tube
➢ If fluid is red/brown/haemorrhagic then gastric lavage
b) flank trochar decompression
➢ large bore catheter or needle;area of greatest tympani on percussion or ultrasound guided
86
GDV pre-op considerations?
* Antibiotics are indicated perioperatively
* Corticosteroids is controversial (best avoided)
* Pre-oxygenate
* Opioid analgesia (methadone)
* Rapid intravenous induction and intubation
* Intravenous fluids are continued at 10-20ml/Kg/hr (monitoring)
* Avoid nitrous oxide
* Avoid NSAIDS initially
87
Prevalence of cardiac arrythmia with GDV?
* 40-50%
* 25% at presentation or develop post op (reperfusion injury)
* Unlikely to cause sudden death
88
If. wehave an arrythmia what do we need to treat?
* hypotension/poor pulses
* pre-existing cardiac disease
* VPCs or R-on-T phenomenon
89
How do we do this?
* Lidocaine bolus(2-4mg/kg)
* CRI if bolus effective
* Supplement if hypomagnesaemic, (low magnesium arrhythmic in any patient)
* Check K+, lidocaine is ineffective with hypoK+
* Only use lidocaine without adrenaline
90
What do we see /do when going into sx of a GDV?
* usually twists clockwise 180-270º
* →pylorus left cranial and body bulging ventrally and to the right
* greater omentum stretched over the stomach
91
Give steps to repositioning
1. Surgeon stands on right of patient
2. Grasp pylorus (on left) with right hand
3. Pull ventrally while pushing body dorsally with left hand
4. Pass orogastric tube
5. Lavage (7-10ml/kg of warm water/saline) until gastric contents removed
6. Evaluate organs for necrosis
➢ partial gastrectomy, invagination
➢ +/- splenectomy
92
What is often done after repositioning and why
» prevent recurrence GDV, (Hiatal hernias)
* Permanent adhesion between pyloric antrum and right abdominal wall
93
What types of gastropexy can we do?
➢ Belt-loop gastropexy
➢ Circumcostal gastropexy
➢ Tube gastropexy
➢ **Incisional gastropexy**
## Footnote
recurrence 75% lower if gastropexy done
94
How do we do gastropexy
1. 5cm incision right ventrolateral abdominal wall
2. 5cm seromuscular incision pyloric antrum midway between greater and
lesser curvatures
3. Suture cranial incision edges with continuous suture starting dorsally
4. Suture caudal incision edges
95
When might we do a prophylactic gastropexy
» Dogs at risk
* relative or Great Dane or previous dilatation with no volvulus
» When neutering – OVH, more invasive if male
» Can be done easily laparoscopic assisted or endoscopic assisted
96
What post op GDV care?
* Continued fluid therapy
* monitor inputs/ouputs (urinary catheter) and vital parameters
* Arrhythmia monitoring and management
* Oxygen supplementation
* Water when able to drink and food soon after
* smaller meals if gastric resection
* Pain control - opioids
* Pro-kinetics (metoclopramide)
* H2 blockers, sucralfate
97
What are some prognostic indicators ?
* recumbency, depression, coma on presentation, gastric necrosis, arrhythmia → increase mortality
* time between onset of signs and presentation & time between presentation and surgery not related to outcome
98
Describe tube gastrostomy
* Prolonged inappetance
* Bypass oral cavity/pharynx/oesophagus
* Gastric decompression
* Gastropexy –GDV, hiatal hernia, Gastroesophageal intussusception
* CI – gastric disease, vomiting
99
What is Hypertrophic pylorogastropathy?
Pyloric outflow obstruction
100
How is Hypertrophic Pylorogastropathy classified?
1. muscular hypertrophy
OR mucosal hypertrophy
2. Congenital - muscular
* young Boxers, Bulldogs, Boston Terriers and Siamese cats.
OR
Acquired - mucosal or mucosal & muscular
* small /toy breed dogs (Lhasa Apso and Maltese)
101
What CLs & Dx of Hypertrophic Pylorogastropathy
* Clinical signs: vomiting partially digested food (6-7 hours after eating)
* Diagnosis: history, delayed gastric emptying on barium meal (> 12-24 hours), ultrasound and endoscopy
102
What surgical technique based on type ?
* muscular – pyloromyotomy
* muscular & mucosal – Transverse or Y-U advancement pyloroplasty
* [Pylorectomy with gastroduodenostomay (Bilroth1) = excision and anastomosis of stomach to the duodenum]
➢ Difficult, risks, rarely considered
103
What is the most common cause of gastric neoplasia
* ADENOCARCINOMA -70-80% in dogs;
but also : leiomyosarcoma, gastrointestinal stromal tumour (GIST), lymphoma, mast cell tumour, extramedullary
plasmacytoma and fibrosarcoma
104
What are some other types of gastric neoplasia might see
* Lymphoma most common in cats
* Benign; leiomyoma, hypertrophic gastropathy or adenoma
105
CLS of Gastric neoplasia
* progressive vomiting, haematemesis, anorexia and weight loss
* Microcytic hypochromic anaemia, faecal occult blood
106
Tx of gastric neoplasia?
surgical (apart from lymphoma)
* non resectable if on lesser curvature
* pyloric resection high morbidity
* check for mets
107
What happens with gastric adenocarcinoma?
➢ Diffuse infiltration (hard stomach wall, difficult to distend and biopsy on endoscopy
➢ Ulcerated mucosal plaques
➢ Discrete polypoid mass
108
What common signs for gastric adenoC?
- Pyloric antrum or lesser curvature (not good)
- High metastatic rate, regional LNs, liver and lung
109
Dx for gastric adenoc?
- Positive or double contrast radiography
- US
- Gastroscopy & Biopsy
- CT
