22 – Adhesions Flashcards
1
Q
What are adhesions?
A
- Type of ‘scar tissue’ form b/w organs and tissue after abdominal surgery
o Form as result of injured tissues during surgery
2
Q
Dogs and cats: incidence of adhesions
A
- RARELY a problem after abdominal surgery
- *active fibrinolytic system
3
Q
What are the 2 species that have issues with adhesions?
A
- Horses
- Humans
4
Q
Horses: incidence of adhesions
A
- COMMONLY associated with surgical diseases of SI
- Most common cause of RECURRENT abdominal pain in horses after SI
- Most common reason for DEATH after surgery in horses with SI lesions
5
Q
What are the risk factors in horses?
A
- SI lesions
- Prolonged post-operative ileus
- Repeated exploratory celiotomy
- Age (HIGHER INCIDENCE IN FOALS) (link with human babies)
o <30 day old - Peritonitis and abdominal abscesses
6
Q
What is the pathogenesis of adhesion formation?
A
- Predisposes adhesions formation: inflammation and ischemia
o *Increased fibrin deposition and decreased fibrinolysis - Coagulation cascade
7
Q
What are the 2 categories of peritoneal injury that predispose to adhesions?
A
- Inflammation
- Ischemia
8
Q
Inflammation results from
A
- Peritoneal trauma
- Infection
- Bacterial contamination
- Foreign material
9
Q
Ischemia results from
A
- Strangulation lesion
- Vascular compromise (Strongylus vulgaris)
- Intestinal distention
- Tight suture placement
10
Q
EXAMWhat is the key regulator FIBRINOLYSIS?
A
- tPa (tissue plasminogen activator)
11
Q
In normal conditions: what does peritoneal fibrinolytic activity cause?
A
- Lysis of fibrin and fibrinous adhesion
- *lysis at 48-72hours
12
Q
When are ‘permanent’ fibrous adhesions formed?
A
- 7-14 days after surgery
13
Q
How do adhesions become a clinical problem?
A
- Compress or distort intestine
- Narrow intestinal lumen
- *impedes normal passage of ingesta
14
Q
Fibrinous adhesions
A
- Rarely causes clinical problems
- Undergo fibrinolysis
o Lysis 48-72hrs
15
Q
Omental adhesions: non-equine species and horses
A
- Develop primary to increased vascular supply
- Rarely cause clinical problems
- If in HORSES: could lead to strangulation
16
Q
Fibrous adhesions
A
- Form inadequate fibrinolysis
- Result from ingrowth fibroblasts and endothelium
- *cause clinical signs: already mature and we can’t break them down
17
Q
Omental adhesions: severity
A
- Most benign adhesion
- May entrap SI
- (take it out in horses?)
18
Q
Focal fibrous adhesions: severity
A
- Intestine to the mesentery
- Intestine to the incision
- Intestine to the peritoneum
- Do NOT cause distortion or kinking of intestine
- May predispose to obstruction or stricture in SI
- Ex. intestine-to-intestine adhesion leading to intestinal volvulus
19
Q
Steps for a focal fibrous adhesion leading to obstruction?
A
- Cause distortion of mesentery or intestine
- Sharp convolutions
- Impeded flow ingesta
- Cause obstruction
20
Q
What happens if you have adhesive fibrous bands between intestinal loops or between intestine and mesentery?
A
- Incarcerate SI
21
Q
Massive fibrous adhesions: severity
A
- Most severe form
- b/w multiple loops of SI
22
Q
What are the primary objective to prevent adhesions?
A
- Minimize peritoneal and serosal inflammation
- Maintain or enhance fibrinolysis
- Mechanically separate adhesiogenic surfaces
- Stimulate intestinal motility
- *prevent therapy should begin at surgery and continued for 3-4 days post-operatively
23
Q
What are some important intra-operative considerations to prevent adhesions?
A
- Meticulous aseptic surgical technique
- Halstead’s principles of surgery
- Starch gloves
- Keep bowel moist
24
Q
What is the most important principle to prevent adhesions?
A
- Meticulous aseptic surgical technique (intra-operative)
25
What are Halsted’s principles of surgery?
- Gentle handling of tissue
- Meticulous hemostasis
- Removal of damaged tissue
- Minimize exposure suture
- Minimize surgical time
26
Starch powder gloves
- Cause peritoneal inflammation
- Enhance post-operative adhesion formation
- *RINSE surgical gloves with sterile fluid (saline solution)
27
Keep bowel moist
- Avoid drying of serosa
o Continuous lavage
o Warm sterile isotonic fluid
o Prevents desiccation
28
Anastomotic technique: perianastomotic adhesion formation
- Mucosal exposure
- Leakage at anastomosis
- Suture exposure
29
Intra-operative abdominal lavage
- Sterile isotonic solutions
o Saline solution
o Lactated ringers solution
- Removal of blood, fibrin, and inflammatory mediators
- DECREASE adhesion formation
o Hydroflotation
30
If doing a contaminated procedures what should you do at end of surgery to reduce contamination and amount of fibrin?
- 10L of sterile saline
31
What are some examples of protective tissue coating solutions?
- Mechanical lubricating barrier (serosal and peritoneal surfaces)
- Application of viscous solution (serosal surfaces and before manipulation)
- High-molecular-weight viscous polymer solution (ex. 1% sodium carboxymethylcellulose)
32
1% sodium carboxymethylcellulose (“belly jelly”)
- Most commonly used
- Cheaper
- 1-2L for a 450kg horse
- ‘siliconizing’ effect on bowel
33
Omentectomy
- Controversial
- Omental adhesions can cause abdominal pain
o Tension of mesentery
o Serve focus intestinal obstruction/strangulation
34
Post-operative: abdominal lavage
- Hydroflotation effect
o Seperates intestinal serosal surfaces
o Remove inflammatory mediators
o Remove peritoneal fibrin
- Ex. pezzar catheter or indwelling chest tube
35
Post-operative: abdominal drain
- Drain placed at surgery
- Drain placed standing
- 10L LRS
- Lavage performed at: 12, 24 and 36 hours
36
What are some pharmacologic adhesion interventions?
- Broad spectrum antibiotics
- NSAIDs: flunixin
- DMSO
- Ex. heparin
37
Heparin
- Acts as anticoagulant via antithrombin III
o Minimize fibrin
- Enhances fibrinolysis (increased tPA)
- Systemic administration (decreased PCV in horses)
38
How can you prevent post-operative ileus?
- Stimulate intestinal motility
- Prokinetic agents
o Lidocaine CRI (stimulates motility and is an anti-inflammatory and analgesic)
o Erythromycin
o Metoclopramide
o Bethanechol
39
What happens with less severe adhesions? How do you treat it?
- Recurrent colic
- Managed medically: flunixin
- Low-residue diets
o Pelleted rations
o Grazing
40
Severe restrictive adhesions: treatment
- Intestinal obstruction
- Strangulation lesion
- Repeated celiotomy
- Euthanasia
41
What are some surgical treatments of adhesions?
- Removal of devitalized intestine
o Establish functional passage of intestinal contents
- Adhesiolysis: breakdown of adhesions
42
Adhesiolysis
- Risk of new adhesion formation: “de novo adhesions”
- Resection potential adhesiogenic tissues
- May need to do an intestinal bypass
