Surgical Treatment of Small Intestinal Disease Flashcards
1
Q
What is the duodenum suspended by?
A
Mesoduodenum
2
Q
he body of the pancreas and right limb of the pancreas are closely associated with the descending duodenum, what does it lie within?
A
Mesoduodenum
2
Q
What fixes the duodenum as it passes cranially?
A
duodenocolic lig
3
Q
What does the duodenocolic ligament attach?
A
Mesoduodenum to the mesocolon
4
Q
The duodenum continue as jejunum, being the portion of intestines at this transition termed
A
Duodeno-jejunal flexure.
5
Q
What is the majority of the SI?
A
Jejenum
6
Q
What suspends the jejenum?
A
Mesentery
7
Q
What distinguishes the ileum?
A
Vessels on ant mesenteric surface
8
Q
Where is common in SI for FB?
A
Foreign bodies can become lodged at the caudal duodenal flexure due to its change in direction (from passing caudally to cranially)
9
Q
How to access caudal duodenum?
A
Cut duodenocolic lig.
10
Q
The mesentery attaches the ?and the to the craniodorsal wall of the abdomen in the cranial sublumbar region by a short attachment called the root of the mesentery.
A
jejunum
ileum
11
Q
Do not twist the small intestines round the root of the mesentery because..?
A
This would occlude the intestinal vascular and lymphatic circulation;
12
Q
Do not leave holes in the mesentery that organs could herniate through and become..?
A
Strangulated
13
Q
Where does greater omentum attach in the abdo?
A
Drosally
14
Q
Where/which organ does the greater omentum attach?
A
Greater curvature
15
Q
Can you list the functions of the omentum? (4)
A
Provides a rich source of angiogenic and neurotrophic factors.
Acts as a reservoir of peritoneal immune cells.
Assists in peritoneal lymphatic drainage.
Has adhesive properties, contributing to encapsulation of inflammatory processes and haemostasis.
16
Q
Adhesion of the omentum over an intestinal wound provides..?
A
Oxygen needed for wound healing,
Allows early revascularisation,
Delivers immune cells to limit infection,
Isolates areas of inflammation and infection Drains lymphatic fluid away.
17
Q
The proximal duodenum receives blood from branches of the..?
A
Celiac artery
18
Q
What artery supplies the caudal half/two thirds of the descending duodenum and the remainder of the small intestine?
A
Cranial mesenteric
19
Q
In dogs, small islands of lymphoid tissue are often identified as raised circumscribed oval “masses” - what are these?
A
Peyers patch
20
Q
What are the 4 layers of intestine?
A
Mucosa
Submucosa
Muscularis
Serosa
21
Q
Total replacement of mucosa epithelium takes how long?
A
2-6 days
22
Q
What are present in the submucosa? (3)
A
Blood vessels
Lymphatics
Meissener plexus
23
Q
What is the submucosa rich in?
A
Collagen
24
Muscularis:
This has a A) circular layer of smooth muscle and a thinner b) outer layer of smooth muscle.
A) thicker inner
B) longitudinal
25
What plexus is located between the circular and longitudinal muscle layers?
Auer myenteric
26
What is the serosa continuous with?
Peritoneum
27
Which intestine layers is the strength holding layer when placing sutures in the intestines?
Submucosa
28
Basic functions of the intestine? (4)
- Digestion
- Nutrient absorption
- Motility
- Secretion and absorption
29
Diseases of the small intestines can broadly be categorised by the main initial pathophysiologic event which can be...? (5)
- Inflammation
- Infection
- Obstruction
- Altered motility
- Disruption of vascular integrity
30
IS the following condition; intramural, extramural or mural?
Intussusception
Intramural
31
IS the following condition; intramural, extramural or mural?
Malposition/volvulus
Extramural
32
IS the following condition; intramural, extramural or mural?
Adhesions
Extramural
33
IS the following condition; intramural, extramural or mural?
FB
Intramural
34
IS the following condition; intramural, extramural or mural?
Stricture
Mural
35
CS of small intestine dx? (8)
V+
D+
Inappetence
weight loss
abdominal pain
Abdo distension
Lethargy
Collapse
36
What are indications to perform an exploratory celiotomy? (7)
Suggestion of abdominal mass;
External evidence of a penetrating abdominal injury;
Signs of intestinal obstruction
Radiographic or more typically ultrasound diagnosis of intussusception;
Free abdominal fluid containing mainly neutrophils, especially if degenerate neutrophils and intra and extracellular bacteria seen on cytological evaluation;
Pneumoperitoneum in absence of recent abdominal surgery;
Further investigation of gastrointestinal disease by intestinal biopsy.
37
Why does free abdominal fluid containing mainly neutrophils (especially if degenerate neutrophils and intra and extracellular bacteria seen on cytological evaluation) indicate surgery?
Suggests septic peritonitis - This is a surgical condition that requires exploratory celiotomy to identify and address its cause and to lavage the abdomen.
38
Why is pneumoperitoneum in absence of recent abdominal surgery is also an indication for exploratory celiotomy? (2)
-Gastrointestinal perforation
- Penetrating injury
39
What bloods should be included with an acute abdomen?
Lactate
40
Disadvantage of abdo U/S for assessment of SI dx?
- Hampered by gas in GIT
41
Advantages of GI u/s? (3)
Sensitive for identification of free abdominal fluid;
Can allow a crude assessment of motility;
Can be performed in the conscious patient.
42
Pros (1) and cons (2) of CT scan for SI dx?
Pro - Excellent anatomy detail
Cons - Not that available, expensive
43
Pros (2) and cons (2) of endoscope for SI dx?
Pro:
Can be therapeutic in addition to diagnostic (retrieval of gastric foreign bodies);
not seen;
Mucosal biopsies can be collected for histopathology.
Cons:
Limited to assessment of the stomach and proximal duodenum;
Only shows mucosal lesions, deeper lesions are
44
Where are SI surgical biopsies taken?
Antimesenteric wall
45
Dehiscence rate of surgical SI biopsy?
1-2%
46
Pros of surgical biopsies? (2)
- Full thickness biopsies
- Maximise hiso interpretation
47
How to approach a linear FB where attached to tongue (and no septic peritonitis)
The string anchor point can be cut and removed from the mouth whilst the distal portion is allowed to pass distally. In many of these cases the foreign body will be passed uneventfully in 1-3 days.
(progress to Sx if complications)
48
What is an intussusception?
Section of intestines invaginates into an adjacent segment
49
Which direction does an intussusception tend to happen?
normal peristalsis (a direct or normograde intussusception
50
What leads to intramural haemorrhage, loss of blood into intestine lumen and subsequent bloody D+ with an intussusception?
The low-pressure veins in the affected segment will be compressed before compression of the arteries
51
What type of obstruction do intussusceptions cause?
Partial
52
How to distinguish between rectal prolapse and an intussusception protruding?
Passage of a probe between the prolapsed segment and the rectum; if the tissue is prolapsed rectum insertion of the probe between the tissue and the rectal wall will be impossible.
53
Neoplasia causing intussusception is more likely in?
Cats
54
Inflammatory dx causing intussusception is more likely in?
Dog
55
How is enterioplication performed?
he theory behind enteroplication is that it stops the intussusception reforming. It is performed by placing sutures through the submucosal layer, midway between the mesenteric and antimesenteric borders of two adjacent intestinal loops. The entire jejunum is plicated.
56
If intussusception is reduced - what should happen next?
Biopsy! For underlying cause (of if end to end send segment)
57
The most prevalent intestinal tumours in dogs are? (3)
Adenocarcinoma
Lymphoma
Mesenchymal tumour
58
What do intestinal tumours in dogs tend to develop as?
Localised annular or expansile mass lesions.
59
How does lymphoma lesions develop as in dogs?
Commonly - diffuse and infiltrative.
Also as localised
60
Most common intestinal tumour in cats?
Lymphoma
61
Common intestinal tumour sign in cats/dogs?(4)
- V+
- Lethargy
- Weight loss
- Inappetence
Occasionally can palp mass
62
For diffuse and infiltrating tumours, what can be see on ultrasound?
Loss of layering
63
What should on u/S of abdo mass? (2)
- Assess local LN
- Aspirate LN/other lesions
64
What additional imaging should be taken for intestinal neoplasia?
Thorax radiographs
65
Tx of intestinal neoplasia?
Enterectomy with margins of 5-10cm
66
Where is a wide margin of intestinal neoplasia difficult and why? (2)
Duodenum - access difficult
+ presence of panc + common bile duct
67
How common are intestine strictures?
Rare
68
What is the causes of an intestinal stricture? (3)Highlight most common
Previous surgery ****
Local severe inflammation
2ry to annular neoplasia
69
How to treat intestinal stricture?
Resection
70
When are intestinal biopsies indicated? (3)
- Chronic D+ (when blood/faecal -ve)
- U/S shows abnormal thickness/wall layers
- Grossly abnormal at ex lap.
71
How are intestinal biospies made with a scalpel:
Include length, where, distance.
A longitudinal incision approximately 15 mm long along the antimesenteric border of the intestines. A second incision is made parallel to the first incision at a distance approximately 2-3 mm away from the first incision. The incisions are joined to complete collection of the intestinal biopsy.
72
Other than an incision, how else can an intestinal biopsy be made?
Dermatology biopsy punch to collect the biopsy; 4-6 mm diameter
73
Care when using biopsy punches for intestine biopsy - why? (2)
- Ensure does go through to far side!
- Make sure doesnt drop into lumen
74
Breed at risk of mesenteric volvulus? (2)
GSD
Pointer
75
What is a mesenteric volvulus?
The intestines twists around the root of the mesentery resulting in obstruction of the lymphatic vessels and cranial mesenteric artery and vein.
76
What results in vascular engorgement and oedema of the small intestinal wall followed by ischaemic necrosis with mesenteric torsion?
Firstly, the low-pressure veins and lymphatic vessels are obstructed, followed by obstruction to flow through the cranial mesenteric artery and its branches
77
What is the onset of clinical signs with mesenteric volvulus?
Clinical signs are peracute to acute, with rapidly progressive abdominal distension, haematochezia, and shock.
78
Tx for a mesenteric root torsion?
Treatment includes rapid and aggressive fluid resuscitation and immediate surgery to reduce the torsion of the mesenteric root.
79
Why do dogs with mesenteric volvulus normally die?
Circulatory, endotoxic and cardiogenic shock because by the time of diagnosis the intestines are necrotic.
80
If there is a volvulus is only segmental, resection and anastomosis; what is prognosis?
Good
81
Surgery: Enterotomy for FB; minimal contam
Class this surgery?
Antibiotic use?
Class: Clean contaminated
ABx: Antibiotics given at induction, repeated every 90 minutes throughout the surgical procedure and discontinued postoperatively
82
Surgery: Enterectomy for FB; minimal contam
Class this surgery?
Antibiotic use?
Class: Clean contaminated
ABx: Antibiotics given at induction, repeated every 90 minutes throughout the surgical procedure and discontinued postoperatively
83
Surgery: Enterotomy for FB; contaminated; lavaged and suction
Class this surgery?
Antibiotic use?
Class: Clean contaminated
ABx: Antibiotics given at induction, repeated every 90 minutes throughout the surgical procedure and discontinued postoperatively
84
Surgery: Enterectomy for FB; contaminated; lavaged and suction
Class this surgery?
Antibiotic use?
Class: Clean contaminated
ABx: Antibiotics given at induction, repeated every 90 minutes throughout the surgical procedure and discontinued postoperatively
85
Surgery: Enterectomy for FB; septic peritonitis due to perfroration
Class this surgery?
Antibiotic use?
Class: Dirty
ABx: Antibiotics given at induction, repeated every 90 minutes throughout the surgical procedure and continued postoperatively for a 7-10 days course according to patient progress
86
Maximum ABX use post op following contmaination?
An additional dose or two of antibiotics may be warranted to suppress the late growth of contaminating organisms that were not killed by the first doses administered intraoperatively, however, antibiotics should be continued for a maximum of 24 hours postoperatively.
87
The proximal small intestine contains mainly what tpy eof bacteria aorganism? E.g?
Gram-positive organisms including Staphylococcus spp., Streptococcus spp., Lactobacillus spp. and Clostridium spp
88
In the middle and distal small intestine, the total number of bacteria increases and there are larger quantities of (2)
E. coli and Enterococcus spp.
89
The feline small intestine contains primarily what type of bacteria (2) e.g.?
Aerobes like Pasteurella spp., Enterococcus spp., Streptococcus spp. and Staphylococcus spp., and anaerobes including Bacteroides spp., Fusobacterium spp. and Clostridium spp.
90
Appropriate ABx choice for GI surgery?
First generation cephalosporins (cefazolin 22 mg/kg IV)
(Although clavulanate-potentiated amoxicillin has more than 90% efficacy against the common aerobic pathogens.)
91
Loss of sodium, water and bicarbonate leads to ..?
Metabolic acidosis
92
excessive loss of gastric hydrochloride in proximal intestinal obstructions and frequent vomiting may result in..
Metabolic alkalosis
93
What fluid are retained in the circulation and have a longer duration of effect than crystalloids? And may be superiod for SI disturbances
colloid solutions used in combination with isotonic crystalloids
94
Where correction of hypokalaemia is required, potassium infusion rate should not exceed
0.5mol/kg/hr
95
To perform an exploratory celiotomy the incision should extend ..?
xiphoid to the pubis
96
What retractors for ex lap? (2)
Balfour
Gossett
97
How to protect ex lap wound edges?
Saline soaked swabs
98
Other than the GI organs, during Ex lap for FB - what else should be checked? (2)
- Pancreas!
- Mesenteric LN
99
Surgical textbooks suggest various methods for assessing intestinal viability that have been reported in research studies. Name these (2)
- intraoperative injection of fluorescein dye into the mesenteric circulation
- Intraoperative pulse ox
100
Choose the four practical assessments of the intestines that can be used to give subjective information about intestinal viability.
- Intestine wall colour
- Active bleed when incise
- Arterial pulse
- Peristalsis
101
If the viability of the intestines at the site of obstruction is initially unclear; what should you do?
An enterotomy can be performed to remove the foreign body and the intestinal segment allowed 5-10 minutes to recover before reassessment.
102
How to handle SI which has been exteriorised?
- Lay on drapes (jejenum + ileum)
- Pack with saline swabs
103
What are the intestine clamps?
Doyen
104
Which side is intestinal incision?
Anti mesenteric
105
IDEALLLY which side is the FB intestine incision?
Distal
106
End to end anastomosis Mild luminal disparity can be accounted for by...?
Placing the sutures closer together in the narrower (non-dilated) distal segment
107
End to end anastomosis; When there is greater luminal disparity how can this be resolved?
The narrower (normal) distal segment can be cut obliquely and /or cut along the antimesenteric border.
108
Effect of albumin on suture material choice.
In patients that have low serum albumin and may have delayed wound healing a longer lasting monofilament suture such as polydioxanone or polyglyconate is preferred.
109
Needle type for intestine?
Tape point swaged on to minimise trauma associated with passage of the needle through the intestinal wall.
110
What properties of monofilament suture material are of particular benefit when suturing the intestines? (3)
- Do not allow wicking of fluid (and bacteria)
-Less susceptible to bacterial adhesion
-Easier clearance of bacteria by the immune system,
111
Which layer is important because it results in primary intestinal healing with rapid mucosal reepithelialisation and with direct bridging of the defect?
Submucosal
112
To aid accurate apposition of tissue layers everted mucosa can be trimmed from the edges of the intestinal incision using what scissors?
Metzenbaum
113
What activity within the wound and what result responsible for intestinal wall strength, on either side of the incision?
Collagenase activity within the wound will result in loss of collagen,
114
What is probably responsible for most cases of wound dehiscence and septic peritonitis with SI suturing?
If the sutures are placed too close to the wound edges they may “pull through” as the collagen is lost, and the wall weakens.
115
When does intestine wound breakdown happen?
Day 2-5
116
What distance should intestine wound sutures be placed?
3mm from the intestinal wound edge and 3mm apart
117
Which pattern in suture?
Continuous or interrupted patterns approximating patterns
118
What patterns do not compromise the lumen diameter?
Approximating
119
What patterns may result in initial narrowing of the intestinal lumen?
inverting
120
What intestine patterns are more likely to cause adhesion formation?
Everting
121
The use of surgical staplers, however, is often limited by (3)
Cost
Lack of familiarity
Size of device (with cat/small dog)
122
How do stapling devices suture?
Lay a double or triple line of overlapping staples.
123
How can staplers be used for a functional end to end anastomosis
A GIA can be used (with two firings) or in combination with a TA stapler
124
T or F
When closing a shorter enterotomy incision (less than 3 cm) there is often no need to pick the wound edges up at all with forceps; accurate suturing can be done without this.
True
125
What forceps to manipulate large enterotomy incisons?
DeBakey
126
How to place sutures for end to end anastomosis
Pre-place the first suture at the site of mesenteric attachment then pre-place a simple interrupted suture on either side of the first suture at a distance 2-3 mm away from the first.
Once these three sutures are placed these can be tied and the rest of the anastomosis can be completed
127
What size needle to leak test?
22/23 gauge
128
There is no evidence from the veterinary literature that leak testing has any effect on the incidence of postoperative peritonitis. T or f?
True
129
When is leak testing appropriate vs inappropriate for FB removals.
nappropriate for enterotomy it is useful for intestinal anastomoses where it is much more likely that gaps may be present along the suture line,
130
When there is insufficient omentum - what can be used over wound?
Serosal patch can be performed by suturing an adjacent loop of healthy intestines over the intestinal suture line.
131
How to lavaeg abdo - volume/type?
200-300 ml/kg of warmed saline or Hartmann’s solution; this should be removed by suction.
if suction is unavailable large abdominal swabs or sterilised tea towels can be used to soak the lavage fluid, wrung out and the process repeated
132
What catheter is used for abdo suction? Pros of this (2)
A Poole suction catheter
- atraumatic
- less likely to become occluded with omentum compared to other suction catheters.
133
Following surgery before closre - what should you do?
Instruments and gloves should be changed on completion of the intestinal surgery and prior to closure of the abdominal wound.
134
A feeding tube and should always be placed in the following situations (5)
If the patient is debilitated;
If the patient has been inappetent for more than 3-5 days;
If the patient has lost more than 10% of body weight recently;
If the patient is hypoproteinaemic;
If the patient is considered unlikely to eat in the recovery period.
135
What size for esophagostomy tube?
12-20 French gauge
136
How long must an oesophagostomy tube be in place for?
No time
137
How is patient positioned under GA for oesophagostomy tube?
R lateral with the neck extended and forelimbs pulled caudally)
Place sadbag/towel under neck
138
Why is a patient in R lateral for oesophagostomy tube?
Cervical oesophagus lies to the left of midline
139
Placing oesophagostomy;
How to know where to make incision
Carefully place a long-curved pair of narrow tipped Carmalt forceps (or similar) into the patient’s mouth and advance caudally into the oesophagus.
Tilt the forceps laterally so that the tips can be seen “bulging” the skin in the mid third of the patient’s neck.
140
To place oesophagostomy tube; where must the jugular be in relation?
Ventral
141
How to make the incision for oesophagostomy tube?
Using a number 11 scalpel blade make a small (3-5 mm) incision through the skin, subcutaneous tissues and wall of the oesophagus over the tips of the forceps.
142
After a skin incision how is the oesophagstomy tube positioned?
Gently push the tips of the forceps through the incision.
Grasp the distal tip of the oesophagostomy tube in the tip of the forceps.
Pull the forceps, with the feeding tube grasped in the tips, through the incision and out of the oesophagus and then out of the mouth.
Release the feeding tube from the forceps and pass the feeding tube down the patient’s oesophagus to the pre-measured level.
143
When the oesophagostomy tube is correctly placed the wide end of the tube should be pointing ..?
Towards patient head
144
How to confirm correct placement of oesophagostomy tube?
Lateral x ray
145
How to secure an oesophagostomy tube?
Finger trap
