Surgery Abdo Module 1 Flashcards
What are classifications of wounds at surgery?
Clean: non-traumatic, uninfected operative wounds that only involve skin and musculoskeletal soft tissues
*Prophylactic abs in clean contaminated or worse
Clean-contaminated: Operative wounds where a hollow viscus (GIT/Resp/Urinary tract) is opened in a controlled manner with no spillage or contamination of surrounding tissues
Contaminated: During surgery bacteria has entered a normally sterile environement but for too brieg a period to allow infection to become established (leakage of intestinal contents into abdo cavity)
Dirty: Surgery is carried out to control an established infection (peritonitis/total ear canal abalation)
What are predictors of SSI?
- Wound classification system (clean, clean-contaminated, contaminated, dirty)
- Operative technique
- Length of surgery - 30% greater risk of infection with each hour of surgery
- Health of the patient
What is the MIC breakpoint?
the chosen concentration of an antimicrobial which indicates whether a species of bacteria is susceptible or resistant to the antimicrobial
What are the 5 regions the abdomen can be divided into for exploration?
- Cranial abdomen
- Caudal abdomen
- GIT
- Right paravertebral region
- Left paravertebral region
What are Halsted 6 surgical principles
- Asepsis and aseptic surgical technique: patient prep, surgical approach
- Sharp anatomic dissection - transecting ligaments and falciform fat to improve exposure
- Atraumatic tissue handling and surgical technique - stay sutures, haemostasis, lavage and suction, correct instruments, preventing tissue dessication,
- Removal of devitalised tissue from the surgical wound - lavage, packing off and isolating organs, regloving to close
- Haemostasis and preservation of bloody supply to tissues - packing off and allowing normal haemostatic process v. active stoppage by ligating/monopolar/bipolar
- Accurate tissue apposition, minimising tissue dead space without excess tension on tissue
- when closing abdo peritoneum inclusion not recommended
- choosing the right suture material for the closure
- correct knots and sutures
What are the layers of the GIT
- Mucosa
- Submucosa - important suture holding layer
- Muscularis - smooth muscle
- Serosa
What are the stages of GIT healing
Lag phase: 1-3/4 days fibrin clot stage, minimal strength but will prevent some leakage - most likely stage to break down (72-96hrs)
Proliferation phase: 3/4-14 days fibroblasts causing epithelial migration and increased wound strength and immature collagen
Maturation phase: 14-180 days, less clinical importance reorganisation and remodelling of collagen
What can the omentum be used for?
helps to seal leaks
helps bring nutrients and lymphatic drainage
sutures v. wrapping
What is the use of serosal patching?
- Useful in reinforcing and sealing intestinal wounds where leakage is anticipated
- Good where multiple GI wounds are present in the
intestinal tract or used following perforation and necrosis - Reinforces seromuscular and submucosal layer which provides resistance to intraluminal pressures
How to carry out an enterotomy
- Exteriorise bowel to be incised and pack off from abdominal cavity
- Milk away contents cranially and caudally
- Incision is made distal to the obstruction: longitudinal incision with 15 blade in the antimesenteric portion of the intestine
- With eliptical biopsy cats need transverse closure
- Serosal patching
Closing an enterectomy
- Sutures on mesenteric and anti-mesenteric border and then simple continuous
- cats: simple interrupted to avoid purse string sutures
Disparity of the lumens:
- spatulating smaller lumen at antimesenteric border
- larger lumen be partially closed with a simple continuous pattern until to matches that of remaining colon or proximal duodenum
What are alternatives to suturing GIT
- Stapling devices
- main advantage of stapling is the ease in which c
intestine of different diameters can be
anastomised - less tissue manipulation
- no difference in wound bursting strength or
absolute strength - same disadvantages as hand suturing: leakage,
abscess formation, late FB obstruction at staple
site - larger dogs
- reduced surgical time
- main advantage of stapling is the ease in which c
What are causes of small bowel obstruction
Intraluminal, Intramural, Extramural
1. FB
2. Tumors
3. Strictures due to trauma/prior surgery
4. Intussusception
5. Strangulation
6. Abscesses
7. Adhesions
Pathophysiology of invagination and causes
Invagination of a portion of intestine due to vigorous contraction of one segment into a relaxed segment.
Causes: young dogs: parasitism due to enteritis, older dog: neoplasia
Blood supply to intussuscepted portion of intestine is compromised due to inclusion in invagination. Initially venous occlusion with edema of the bowek and if prolonged arterial occlusion and necrosis
Eventually fibrous adhesions can form making spontaneous or surgical reduction difficult
following surgery can recurr up to 20% with 72hrs of procedure
Prognostic factors useful for GDV
- Lactate reduction with stabilisation - if doesnt drop or persistently high = poor prognosis (particularly 12hrs)
- Radiographs: dilation v. GDV
- Free abdominal air on x-ray - signs of necrosis
- Thoracic rads: cardiomegaly - poorer prognosis
