SA Sx - Intestines 1

drraythe's version from 2017-09-15 00:32


Question Answer
Principals: If you want to open the intestines, WHERE do you do it?EXTERIORIZE the intestines & then pack off abdominal cavity
Principals: you should engage WHICH layer w/ all sutures?SUBMUCOSA (its the holding layer of the GI)
Principals: in general, what kinda suture?Use small size, monofilament synthetic absorbable or nonabsorbable suture swaged on taper needles (big suture = microtrauma)
Principals: after ur done w/ Sx, what do you wanna cover the Sx site with?Cover surgical site w/ omentum or w/ a serosal patch (check w/ water test - if needs more help, attach omentum)
Principals: before closing, always...LAVAGE ABDOMEN!
What level of contamination/sterility is intestinal Sx considered? What precautions should you take bc of this?Either Clean-contaminated, or contaminated! So, replace contaminated instruments & gloves before closing abdomen (change instruments & gloves!) & Use prophylactic ABx
Recommended prophylactic ABx for Sx, depending on location?(1) Upper & middle SI: 1st generation cephalosporins (cefazolin).
(2) Lower small intestine & large intestine: 2nd generation cephalosporins (cefoxitin) [he noted you could add metronidazole if you were worried about anaerobes (clostridium natural anaerobe of ileum), but for no longer than 48-72 hr]
3 main indications for intestinal Sx?(1) Obstruction
(2) Perforation
(3) Diagnosis (biopsy) → Chronic infiltrative bowel Dz
Basic dimensions of an intestinal biopsy?FULL thickness, about 1cm long, 5mm wide
Appose mucosa accurately w/ what kinda apposition?Simple


Question Answer
What bad problem comes w/ a complete intestinal obstruction?Pressure on the wall → necrosis → perforation → peritonitis
Exs of things that can cz intestinal obstruction?Foreign body
Ileus(mechanical vs Fnxnal)
Neoplasia (carcinoma = napkin ring lesion causing obstruction)
Pythiosis(hunting dog gulf states)
Mesenteric torsion
Who is more prone to mesenteric torsion? What is the characteristic look of these on rads? How quickly do you need to solve this prob?GSD, young animals, hunting dogs more prone. Characteristic "cinnamon bun" look on rads. Need to solve w/in 60min of intake (SUPER HIGH mortality rate...& reperfusion injuries)
Severity of signs depends on what 3 things? (Which combination leads to the most severe probs?)(1) Completeness
(2) Location
(3) Blood supply [Complete, high or strangulated obstruction results in more severe signs]
Explain the "completeness" of an obstruction - what are the 2 types of completeness & which is more severe?Can be either complete of incomplete. A complete is a more severe problem (pressure necrosis), incomplete is sometimes hard to Dx bc a little food DOES get past & might mimic or hide things
Explain the "high vs low" obstruction & which is more severeA high obstruction is more severe, keep in mind loss of electrolytes w/ the location of the blockage (high = alkalosis or & low = acidosis)
Blood supply → strangulated vs non-strangulated: which is more severe? How might appearance of this vary?Strangulated more severe - must consider if arteries are blocked, or veins, or both. If just veins blocked, aa keep trying to bring blood to tissues, tissues become super edematous
Which types of FBs are a cat prob, which are a dog prob?CATS: linear FBs (esp if thread, look out for needle puncturing root of tongue), dogs basically everything else
Whom is Intussusception most common in? Why?Young dogs! Often bc of heavy parasite burden - even after de-wormed, should do a re-check to make sure you got them all. If heavily parasitized, intestines trying to push it through, inc peristalsis → intuss.
How can you Dx intusseption via palpation? Cautions?Feels like a hard/semi hard cigar structure that suddenly tapers into normal bowel loop (dont squeeze too hard or can rupture).
Whom is Mesenteric torsion most common in?Adult dog, especially German shepherd
If you see there is mesenteric torsion & the bowel loops are black, what should you do? Not do?DONT UNTWIST IF BLACK. Resect but look out for short bowel syndrome. Look out for any reperfusion injury
2 types of ileus?Post-operative or post-obstruction
Usual signalment of a PTx w/ intestinal neoplasia?Middle-aged & old dogs & cats
If you see this, what is prolly going on? What is this radiographic look called? How might you go about trying to see things better? This is the "ground glass appearance" often seen w/ peritonitis/fluid in abdomen. So abdominocentesis - drain fluid to take another survey rads. Careful w/ contrast studies - if fluid removed shows things that hint toward perforation, dont do contrast (do US or exploratory)

Obstruction (hypoxia, more stuff)

Question Answer
Sensitivity to hypoxia → which structures are hurt when/at what time? (4 steps of destruction)(1) Superficial villus injury after 20 min
(2) Destruction of villus after 60 min
(3) Transmucosal necrosis after 4 hours
(4) Transmural infarction after about 8 hours
If you see "ground coffee" in the intestines after hypoxia, what do you know?Mucosa sloughed off
Grossly, wall edema & hemorrhage & mucosal sloughing are apparent w/in...(Time)1-3hr
After__(time)_________ the affected segment of intestine is turgid & whole blood collects w/in the lumen4 hr
At _________(time)_________ the affected gut appears black, distended & elongated8-12 hr
Gross necrosis is evident by__(time)_________20 hr
Gaseous bowel distention develops w/in the initial _________(time)_________ after obstruction & is followed by the loss of fluid into the intestinal lumen.12-36 hr
W/o any Tx, death due to hypovolemia occurs in about..3-4d
In short, list the order in which things die from hypoxemia (dont bother w/ times, other flashcards for that)superficial villus injury → destruction of villus → transmucosal necrosis → transmural infarction → wall edema & hemorrhage & mucosal sloughing are apparent → affected segment of intestine is turgid & whole blood collects w/in the lumen → affected gut appears black, distended & elongated → Gross necrosis → Gaseous bowel distention → loss of fluid into the intestinal lumen → death due to hypovolemia
Picture explaining the pathophysiology of intestinal obstruction
If the tissue is very edematous, are you concerned about suturing it?Oh yeah..Its like suturing jello
According to come pics, which part of the SI tends to get torsion?Jejunum
Vomiting more common when _________(where)_________ is obstructed, as opposed to diarrhea which is..Vomiting -upper intestine
Diarrhea - Lower intestine
So you open the abd of a dog & you see that the omentum is adhered onto a piece of intestine. What do you think happened?Greater omentum = police = trying to patch & bring blood supply & bring nourishment & get rid of debris (does adhesion by itself)
Pyloric/proximal duodenal obstruction leads to what acid-base imbalance?Metabolic alkalosis
Mid-duodenal to ileal obstruction leads to what acid-base imbalance?Metabolic acidosis
Fluid loss due to obstruction happens through what 3 ways?(1) Vomiting
(2) Sequestration in intestinal lumen (increased secretion & decreased absorption)
(3) Edema of intestinal wall, especially w/ venous occlusion of intestine
A strangulating obstruction is a simple obstruction + occlusion of the blood supply & results in what 4 problems?(1) Bacterial overgrowth
(2) Inc bowel permeability
(3) Perforation & escape of bowel contents
(4) Peritonitis
Why does strangulating obstruction lead to bact overgrowth?Bact replicate rapidly & no peristalsis to keep them away from abd wall - w/o peristalsis, get bacterial translocation after necrosis (going outside of lumen) → localized peritonitis → generalized peritonitis
5 possible czs of strangulating obstructions?Intussusception
Mesenteric torsion
Strangulated hernia
Some foreign body obstructions
Adhesions / bands
What are some things that inc the chances of adhesions? What might help avoid adhesions?If leave ovarian pedicle too long, if you let viscera get dry, adhesions. So makes sure to keep tissue moist by squirting/lavaging abd to help prevent
What problems can come from hairpin adhesions? peristalsis not working well--food accumulation - obstruction (PTx in pic had OVH a few mos before - must not have kept abd moist)
How would you describe what is going on in these pics? Ileus & dilation (as result of obstruction)
Main CSs of intestinal obstruction?Vomiting, Dehydration
Electrolyte imbalance
Acid-base abnormalities
Abdominal pain
Distended loops of intestine
Palpable abdominal mass
B-Day said...where do most FBs get stuck?Usually in jejunum or duodenum (usually not near ileocolic valve, if get that far, will prolly pass.)
If FB in lower SI, where does telescoping usually take place?Usually telescoping at ileocolic jnxn.
1st part of Tx is stabilizing PTx - how are some ways to do this?Correct acid-base
Fluid & electrolyte abnormalities
Tx for shock if necessary
If the FB gets to the colon, what are you thinking?Prolly will pass (monitor tho)
What are the 2 "worst enemy" FBs?BBQ skewers (perforate easily), tampons (expand a lot & are difficult to get out)
1 of the most common FBs?Socks

Linear FBs

Question Answer
Where might a linear FB be anchored?UNDER THE TONGUE. Always check under cats tongues! ESP if you feel bunching of viscera. Other place it can get stuck is at the level of the pylorus
If you see the linear FB under the cats tongue, what SHOULD you do? What SHOULDNT you do?DO release the attachment from the tongue. (Pick up, DONT pull, cut in half). DO NOT ATTEMPT TO PULL IT OUT FROM THE MOUTH
If you see linear FB coming out of anus, dont...DONT pull it out!
How can a linear FB cz a perforation?If gets embedded in mesenteric side of intestine & starts serrating & cutting through bc peristalsis against an immobile object → can cz preformation
Omg! You see a small thin elongated linear looking object near the thoracic inlet in a cat & you suspect a linear foreign body. Before you attempt Sx to remove this "needle" what should you keep in mind?DO NOT REMOVE THE CLAVICLE THINKING IT IS A NEEDLE.
If there is a needle attached to a FB in a cat, what other structure might you be super worried about?communication behind last molar into the floor of the orbit - CAN MOVE FROM MOUTH TO EYE
2 unique radiographically signs of linear FBs?(1) Intestine placated in cranial abdomen
(2) Teardrop shape of gas bubbles in intestine
What’s this? What usually czs this? Intestinal plication, usually czd by linear FBs
WHICH border of the intestine is usually lacerated by linear FBs?MESENTERIC border (MUST explore & assess it)
How should you approach doing an enterotomy if the linear FB in the intestines is long?Dont do 1 super long enterotomy - do mult normal sized ones
If the intestine is perforated by a linear FB, what is the recc course of action?Intestinal resection & anastomosis is indicated if the intestine is perforated
Once you have removed linear FB & the intestines are still placated, how can you try to return them to their normal position?Try to "milk" them back into place
So along w/ the linear FB pics, there was a pic of a STOMACH being held up w/ stay sutures...why?Bc need to CHECK PYLORUS for where the FB initially got stuck
What is the Anderson technique?Once FB has been freed up, thread it /pass though tip of red rubber feeding catheter. Try to push through normal digestive direction & push path & you are stretching intestine. Make sure no damage to mesenteric border or might get perforation. (Milking cath from outside)
Woah! What’s going on in this radiograph? if you press down on abd w/ a paddle you dec width & then get a more clear pic