Principles of GIT surgery 1, 2 + 3 Flashcards
List Halsted’s 7 principles of surgery
- Gentle tissue handling
- Meticulous haemostasis
- Preservation of blood supply
- Strict asepsis
- Minimal tension
- Accurate tissue apposition
- Obliteration of dead space
Once in the abdomen during surgery, what is the first step?
- Systematically explore the abdomen before you do anything else.
- Complete the whole exploration even if you find an obvious lesion, otherwise you might miss something.
- Evaluate the size, shape, location, colour, consistency and surface contour of organs/tissues.
What is the duodenal dam manoeuvre?
Useful when exploring the abdomen
Grasp the duodenum and retract most of the intestines over to the left to expose the right abdominal roof.
What is the best instrument to use for mobilising/examining gut?
Hands
Why should excess handling of the gut be avoided?
Can cause ileus: temporary lack of the normal muscle contractions of the intestines
Before making an incision into the stomach what should you do?
Use 3-4 stay sutures to stabilise the stomach
Which tissues in the abdomen require extra care when handling? Why?
Liver capsule and parenchyma - friable
List some instruments specialised for use in abdominal surgery
- Self-retaining abdominal retractors.
- Malleable retractors.
- Suction: this is essential for adequate lavage
- Doyen bowel forceps or Allis tissue forceps padded with swabs can occlude the gut lumen when an assistant isn’t available
Describe/name the type of forceps used on abdominal tissue
- Debakey thumb forceps are the least traumatic forceps for handling gut: don’t use large “rat-tooth” types. Use the tip of the forceps on the serosa of the organ or adventitia of vessels, don’t grab a section and crush it
- Use crushing forceps to occlude the lumen of gut that is to be resected but never use them on tissue that you aren’t going to excise.
What abdominal structures / organs do you need to evaluate in an exploratory coeliotomy?
What order should you look at them in?
- Parenchymatous organs first: liver, spleen, pancreas, right kidney and adrenal, left kidney and adrenal
- Intestines: stomach, duodenum, colon, caecum, ileum, jejunum, mesenteric lymph nodes
- Bladder and ureters, reproductive tract (if present)
- Anything else specific to the patient’s problem
When incising into the GI tract you want to incise the least vascularised part of the gut wall, where is this in each part of the gut?
Stomach = Midway between the greater and lesser curvatures
Duodenum, jejunum or colon = the antimesenteric border
Ileum = approximately 2/3 of the way from the mesenteric to the antimesenteric border
Do you need to worry about ‘capillary ooze’ bleeding?
Usually stops spontaneously when the incision is sutured, if not before
How are larger blood vessels vigated?
Synthetic absorbable suture material or vascular clips
Which vessels should be ligated in the SI?
Both the branches of the cranial mesenteric artery running up the mesentery and the terminal arcade vessels running along the mesenteric border of the intestine
In dogs which artery of the colon should not be ligated?
Cranial rectal artery
In dogs, which arteries of the colon can you ligate?
Vasa rectae
Left colic artery
Name some topical haemostatic agents that you may use in the liver
Absorbable gelatin foam or collagen felt can halt diffuse parenchymal haemorrhage
Why is electrocautery of limited use in the liver?
Can ablate the parenchyma, making bleeding worse
Describe the pringle manoeuvre
Can occlude blood flow to the liver for up to 15 minutes by applying pressure to the celiac artery and portal vein at the epiploic foramen
Haemostasis near the border of liver lobes may be achieved using …?
Bulk ligation of tissue (the “guillotine method”)
Which technique is used for a partial lobectomy away from the border of the lobe or for a total lobectomy? Why?
The “finger-fracture” technique
- It allows large vessels and bile ducts to be identified and individually ligated: safer
How is the “finger-fracture” technique carried out?
Carefully incise the liver capsule (or score with the blunt end of a scalpel handle – probably safer) along the line of resection then crush/separate the parenchyma along that line with fingers to expose the large vessels and bile ducts so you can ligate them.
Describe how to perform haemostasis in the pancreas
- Pass a ligature around the area of pancreas containing the lesion or haemorrhaging vessel and tighten, crushing tissue and occluding vessels and ducts. Excise tissue distal to ligature.
- Bluntly separate pancreatic lobules around lesion, isolate blood vessels and ducts supplying affected part and ligate or cauterise, excise tissue.
How can planning your incisions help preserve blood supply to tissues/organs?
When removing a section of gut, incising at approximately 30° to the transverse ensures adequate blood supply to the antimesenteric border and increases the luminal diameter at the anastomosis
How can you assess the viability of intestine?
- Colour should be a healthy pink.
- Arterial pulsations should be present.
- Peristalsis should be present.
Describe the blood supply to the oesophagus and how to preserve it
Segmental blood supply
Rich submucosal plexus
Preserve this by:
- Avoid excessive cautery
- Handle tissue gently
- Place sutures carefully
The blood supply to the the stomach, duodenum, pancreas and spleen arises from which artery?
Celiac artery
Resection of the descending duodenum may compromise the blood supply to where?
The pancreas
When performing a splenectomy which artery should be preserved?
Left gastroepiploic artery - terminal branch of the splenic artery
When working around the pylorus take care to preserve which 2 arteries?
Cranial pancreaticoduodenal and hepatic arteries
List the ways of minimizing contamination of the peritoneal cavity when you open the intestine
- Use moistened abdominal swabs to isolate the area you are working on from the rest of the abdomen before making your incision
- Before opening the intestine, gently “milk” the contents away from the incision site orally and aborally then keep them away by occluding the lumen with atraumatic forceps or an assistant’s fingers
- Elevate the oesophagus and stomach with stay sutures to reduce spillage.
- Discard contaminated instruments and gloves and use clean ones for abdominal closure
Once you have finished an abdominal procedure what should you do before closing up to reduce contamination?
Lavage the abdomen with 1-3L of warm saline before closure.
“Dilution is the solution to pollution.”
Prophylactic antibacterials should be used in which procedures?
Clean-contaminated or contaminated procedures (e.g. gastrotomy, enterotomy or enterectomy, colotomy or colectomy) and in hepatic surgery
When should prophylactic antibacterial be administered?
Give them intravenously just after induction of anaesthesia, continue through the operative period then stop before 24hrs postoperatively
Which antibiotic has good activity against the common GIT contaminants?
Clavulanate amoxicillin
For colonic or hepatic surgery, add an antibacterial effective against anaerobes e.g. …?
Metronidazole