SaSx FINAL - old material Flashcards
4 classifications of operative wounds
Clean - created in Sx, no infection
Clean-contaminated - Sx created but hollow viscus or organ w/ bacteria open, no contents spilled, minor break in technique
Contaminated - Sx but gross spillage in hollow viscus organ, minor break in technique
Dirty - implies infection
Risk of infection ______ every hour
doubles
MC source of surgical wound infection
patients endogenous flora, skin and GIT
Prophylactic antibiotic for wound contamination
Cefazolin IV, 30-60 min prior to incision, q90-120 mins intraop
Therapeutic antibiotics for wound contamination
continue 2-3d after resolution of infection
4 stages of wound healing
- Inflammation
- Debridement
- Repair
- Maturation
Inflammatory phase of wound healing
0-5 days
initiated by tissue damage, hemorrhage = 1st response to injury
vasoconstriction - fibrin clot - vasodilation + inc vascular permeability - leukocyte response (macrophages), platelets
WBC leaking from vessels into wound initiates debridement phase
Debridement phase of wound healing
2-5 days
neutrophils and monocytes initiate debridement phase
monocytes = primary cells for wound healing
macrophages - secrete collagenases to remove necrotic tissue, secrete chemotactic + growth factors, recruit mesenchymal cells
Repair phase of wound healing
3-5 days to 2-4 weeks
macrophages stimulate fibroblast and DNA proliferation
acidic + oxygen rich environment
Granulation tissue - barrier to infection, source of special fibroblasts, surface for epithelial migration
Epithelialization + wound contraction
Maturation/Remodelling phase of wound healing
strength of wound optimized d/t changes in the scar, collagen I increases, III decreases
most rapid gain in strength 7-14d post injury
Golden period of wounds
within 6 hours - insufficient microbial replication to cause infection, can usually manage with primary closure
T/F: alcohol is ideal to flush open wounds
false, damages open tissue, never use
Preferred lavage
sterile isotonic saline or LRS
7-8psi (1L saline bag w/ pressure cuff at 300mmHg)
Number one choice for empirical antimicrobial selection to treat a contaminated wound
Clavulanic acid - potentiated amoxicillin (clavamox)
2 antibiotics that you should take a culture before using
fluoroquinolone and aminoglycosides
Compare TAB to silver sulfadiazine
TAB (Triple Antibiotic Ointment)
broad spectrum, prevention, not effective vs Pseudomonas
can retard wound contraction
Silver Sulfadiazine
DOC for wounds, can tx most gram + and - including Pseudomonas
combine w/ aloe vera to reverse wound retardant effects
Layered vs En Bloc debridement
Layered - MC, excise contaminated SQ (careful in cats can delay wound healing), remove isthmus connections, excise in layers
En Bloc - entire wound excised then closed primarily
Debridement mechanism that is highly selective for devitalized tissue only: A) Layered B) En Bloc C) Autolytic D) Biosurgical
C) autolytic
A dog comes in with an infected wound. The owner said they tried to bandage it but it started smelling like tortillas so they came to the vet. You pull off the bandage and notice blue green pigment on the bandage. What is at the top of your differential list?
Pseudomonas. TAB wont work, will need silver sulfadiazine.
Penrose Drain
passive
fluid travels along drain not inside, don’t fenestrate, MC drain in vet med
remove 5-7d later or risk ascending infection.
daily bandage changes, don’t rely on owner
warm compress to promote drainage, not cold compression
don’t do double exit passive drain
make sure adequately clipped + prepped
Jackson Pratt drain
active
fluid travels inside fenestrated tubing, exits dorsal to wound
strict aseptic technique for placement
aggressive en bloc debridement before closure
remove when fluid: 5ml/kg/d or 0.2ml/kg/h
Modified butterfly catheter
small animals or wounds in challenging areas
Most common used bandage in vet med A) adherent B) non-adherent C) Occlusive D) Semi-occlusive
D - semi-occlusive, allows air to penetrate + exudate to escape from wound surface
Can you use a wet to dry bandage on granulation tissue?
No! Will disrupt healing tissue when removed
Match the moisture retentive dressing (MRD) with the exudate level.
Dressings: calcium alginate, hydrocolloid, hydrogel, polyurethane foam
Exudate feel: high, moderate, moderately high, low to minimal
Calcium alginate - high
Moderately high - polyurethane foam
Moderate - hydrocolloid
Low - hydrogel
T/F: all bite wounds are contaminated
true
4 depths of burns
1) superficial - 1st degree, outermost epidermis, moist, painful
2) Partial thickness - 2nd degree, epidermis + dermis, oedematous, painful, marked inflammation
3) full thickness - 3rd degree, epidermis + dermis, dark brown, non-painful, eschar
4) extension beyond dermis - 4th degree, needs Sx
Who described gentle tissue handling?
Halsted
4 types of pivotal skin flaps
1) rotation
2) transposition
3) interpolation
4) distant
Axial pattern flaps
rely on direct cutaneous artery + vein at base of flap
- caudal superficial epigastric
- thoracodorsal
also, cranial superficial epigastric, vehicular, deep circumflex iliac
A flap composed of skin with muscle, bone or cartilage
Composite flap
Skin grafts
Phase I - 0-72h - contraction of fibrin strands, graft pulled closer to bed
Phase II - 72h-10d - fibrin to fibroblasts, leukocytes, phagocytes (fibrous adhesion)
1) plasmatic imbibition
2) inosculation
3) revascularization
Nephrolithiasis
Ca oxalate + struvite
PE: abdominal discomfort, hydronephrosis
Dx: rads, US (echogenicity to see which stones) check contralateral renal function prior to tx
Tx:
- Nephrolithotomy via ventral midline celiotomy, clamp time = 20 min, sagittal incision, remove stone, culture renal pelvis, flush, catheterize to ensure ureter potency. Close futureless (hold 5 mins for fibrin seal), horizontal mattress. nephropexy to minimize entrapment/torsion
- Pyelolithotomy - incise renal pelvis instead of parenchyma (if dilated or if thats where calculi is) - no occlusion needed, dec hemorrhage risk, no nephron damage
Post op - diuresis, monitor, post op rads
Renal Trauma
CS: hematuria
Dx: contrast excretory urography - see contrast media leak into abdomen (uroabdomen)
Tx:
- minor: conservative
- moderate: Sx repair + omental patching
- severe: nephroureterectomy - ensure other kidney functioning
Hydronephrosis
dilation of renal pelvis + atrophy of renal parenchyma
death if bilateral
Dx: US
Tx: <1w obstruction = resolution, >4w = may regain 25%, nephroureterectmoy
Pyelonephritis
predisposed by damaged parenchyma
Tx: nephroureterectomy
Giant Kidney worm
Dioctophyma renale, fish or frog consumption
Tx: nephrotomy if early enough to cut out worm, otherwise nephroureterectomy
Renal neoplasia
mostly malignant, MC benign = renal adenoma
renal cell carcinoma - male dogs, older, MST 9m. Tx: nephroureterectomy + chemo
Renal lymphoma - MC cats, chemo
Embryonic nephroblastoma - congenital, young (4m), MST 6m - very aggressive
Dx: US best
Tx: exploratory laparotomy, check for metastatic lesions,, preferred Bx method, unilateral nephroureterectomy
Renal Biopsy
high risk of hemorrhage, only do if worth the risk
dont do if coagulopathies, hypertension, chronic hydronephrosis
sample CORTEX not medulla
collect at least 2 samples
US guided = preferred
Renal transplants
rare in dogs, more common in geriatric cats w/ chronic renal dz or failure, expensive
immunosuppression required
owner must adopt + take care of donor
Ectopic ureter
extramural or intramural
female young husky
CS: incotinence (difficulty potty training)
Dx: excretory urography, CT, US - ureter depositing urine in wrong place
Tx: neoureterocystostomy - transplant distal ureter to new place in bladder
- intramural (MC) - perform cystotomy + create new stoma @ level of trigone
- extramural - ligate + transect then place through cystotomy incision
difficult Sx but good Px
Ureterocele
persistent membrane in embryonic development over ureteral orifice
Dx: IV urography - cobra head sign
Tx: intravesicular - ureterocelectomy (remove ureterocele), ectopic - neoureterocystostomy w/ ureterocelectomy
Ureteral Trauma
#1 cause iatrogenic (OHE Sx) Dx: IV urography - localizes lesion Tx: nephroureterectomy (make sure other kidney functional
Ureteroureterostomy
tx damage to more proximal ureter, resection + anastomosis = difficult
Urinary diversion
can’t have urine going through damaged ureter
Ureteral stent - pig tail catheter proximal to anastomosis through bladder to urethra, remove in 5-7d
Nephrostomy tube - divert urine, fenestrated tube from kidney to renal pelvis –> outside patient
Loss of ureter length technique that involves anastomosis of one ureter to the other
Transureteroureterostomy
Urolithiasis
MC indication for ureteral Sx, cats
dx: rads - most radiopaque CaOx, US - dilation of ureter/pelvis
Tx: cystotomy + retrograde flushing + removal via pyelithotomy
Persistent Urachus
urine dribbling from umbilicus, patent urachal canal
omphalitis (umbilical inflammation)
Tx: Sx removal of urachal tube, ventral midline incision
Vesicouracheal diverticulum
MC urachal abnormality in dog
external opening closed, bladder attachment patent, predisposes patient to uroliths + UTI
Dx: positive contrast cystography
Tx: partial cystectomy + diverticulectomy
Bladder rupture
trauma (HBC), iatrogenic (catheterization)
Dx: positive contrast urethrocystogram is best - see leakage of contrast into abdomen. US - free fluid, rads - abdominal fluid + absence of bladder. Abdominocentesis - urea in fluid = serum urea, Creat in fluid > serum creat
Tx: stabilize, then urinary diversion - tube cystotomy w/ cystopexy –> then Sx
VD approach to exploratory laparotomy, check for concurrent injury, close bladder wall + omentalize or serosal patch, place catheter in urethra
Cystic calculi
common, bladder MC, struvite + Ca oxalate
Dx: rads - can see struvite + CaOx (cystine + urate = radiolucent), double contrast cystography - can see urate (Dalmatians!)
Tx: non surgical - hydropropulsion, transurethral cystoscopy, diet (struvite only), electrohydraulic lithotripsy
Sx: cystotomy - MC sx of bladder, ventral approach preferred, don’t cut lateral ligaments, close w/ simple continuous + inverting, can also do one or two layer inverting pattern, leak test, post op rads
Polypoid cystitis
uncommon, middle aged female dogs, resembles TCC but non-neoplastic, hematuria when polyps rupture
Bladder tumors
Dog: uncommon, TCC MC, 97% malignant, old Scottish terriers, trigone
Cat: rare, bladder 2nd MC site for UT tumor (renal lymphoma #1), TCC MC bladder tumor, middle aged males, apex
Transitional cell carcinoma
obesity predisposes
Dx: rads, US, transurethral Bx, bladder tumor antigen test - AVOID FNA (readily exfoliates = tumor seeding)
Tx: partial cystectomy w/ >1cm borders, chemo, poor Px
hypospadiasis
MC developmental abnormality of male genitalia, incomplete formation of penile urethra, Boston terriers
Urethral prolapse
protrusion of urethral mucosa through orifice, young male brachycephalics
PE: bleeding from prepuce, licking, red-purple mass
Tx: mild: reduce + purse string or urethropexy
severe - resection + anastomosis
urethral trauma
Dx: positive contrast urethrogram
Tx: urinary diversion w/ urethral catheter or cystotomy tube if incomplete or small laceration, complete rupture –> anastomosis or repair w/ urinary diversion
Urethral obstruction
common in dogs + cats, male > females
dog: ischial arch + caudal to os penis, stones
cat: distal 1/3 urethra, mucus plugs, crystals, stones
Dx: rads
Tx: cystotomy after hydropulsion, urethrotomy if unsuccessful (temporary opening in urethra)
Urethrostomy = permanent opening of urethra at new site, dogs = scrotal, cats = perineal
Vestibulovaginal stenosis
CS: vaginitis, UTI, painful breeding, hydrocolpos
Dx: aseptic exploration, contract rads, <0.2 = severe stenosis. Vaginoscopy = best, direct visualization
Episiotomy
incision of vulvular orifice to access vestibule + vagina
Recessed vagina
conformational abnormality, vulva engulfed by skin
medium/large overweight dogs, early OHE not a cause
CS: skin fold dermatitis, vaginitis, recurrent UTI incontinence
Tx: cleansing, weight loss, episioplasty
Vaginal hyperplasia
inc estrogen levels during proestrus/estrus
<2y large breeds, one of first 3 cycles, mucosa protrudes from vulva, tissue from ventral vaginal floor
Tx: conservative management, E collar, resolves at end of tissue, OHE to prevent
Vaginal prolapse
donut shaped appearance
Tx: manual reduction, hyperosmotics, OHE
Ovarian Remnant syndrome
recurrence of estrus after OHE, dogs> cats
CS: vulvular enlargement,t attraction to males, vaginal cytology mimics heat cycle
Tx: Sx, usually at caudal pole of kidney, avoid ureter
Dystocia
can’t expel fetus, 75% maternal cause
primary uterine inertia - parturition fails, birth canal/fetus = normal, no neonates born. CS = prolonged gestation
secondary - uterine fatigue
tx: primary w/ oxytocin, c section if doesnt work or secodnary
C sections
incision midway b/wn xyphoid + umbilicus to cranial pubis, exteriorize uterus, pack w/ lap sponges, perform hysterotomy
clamp umbilical cord 2-6cm
if hemorrhage or involute not started, oxytocin IM
remove puppies <60s if en bloc resection
Testicular torsion
rare, abdominal, inguinal or scrotal
CS: anorexia, lethargy, shock, death
Dx: US + doppler, flow absent
Paraphimosis
inability to retract penis into prepuce, congenital or acquired, can lead to necrosis
Tx: lube, hyperosmolar agents, preputiotomy, preputial advancement
recurrent - phallopexy, amputate penis if necrotic
Phimosis
inability to protrude penis
Tx: enlarge preputial orifiice
Prostatic cysts
accumulation glandular secretions in prostate of older intact males
CS: related to caudal abdominal ass, asymptomatic, distension, incontinence + dysuria
Dx: palpation, rads, US, FNA
Tx: if small, Sx + castration, if large, resection, drainage, omentalization, castration
Benign prostatic hypertrophy
aging, inc sensitivity to testosterone receptors
CS: asymptomatic, dyschezia, ribbon feces
rectal: symmetrical, large, no pain
Tx: castration
Prostatitis
middle aged-older, ascends up urethra, E. coli MC
CS: dyschezia, painful urination, purulent discharge
pathognomonic: capsular tissue surrounding fluid, FNA confirms
Tx: mild - castrate, enrofloxacin, TMS; severe - mild + supportive care + drainage
Prostatic neoplasia
castration has no effect
CS: dysuria, hematuria, straining to defecate, ribbon like feces, lameness (metastasis), large, asymmetrical prostate
Dx: rads, US, FNA
Tx: palliative
MC approach to thoracic surgery?
lateral thoracotomy
Lung lobe torsion
rotation of lungs on hilus, venous + lymphatic congestion, consolidation, pleural effusion
deep chested dogs + pugs
CS: acute onset, dyspnea, tachycardia, exercise intolerance, hemoptysis
Dx: pale MM, dec lung sounds ventrally, thoracocentesis - serosanguinous or chylous
Tx: stabilize, DONT UNTWIST, lung lobectomy, chest tube for 3-5d
Px: good for pugs, not for other breeds
monitor bc secondary torsion can occur
Idiopathic chylothorax
dx: intestinal lymphangiography - oil/cream PO, methylene blue into ileocecal node or H2O sol contrast into catheterized lymphatic
Tx: Sx must include thoracic duct en bloc ligation
chest tube post op
Diaphragmatic hernia
abdominal organs in thorax, caused by trauma
CS: acute - resp distress, shock. chronic - resp + Gi signs
Dx: US
Tx: stabilize, Sx. stomach herniated = emergency. diaphragmatic herniorraphy - ventral midline abdominal approach, put organs where they belong.
Peritoneopericardial diaphragmatic hernia
congenital communication b/wn peritoneal cavity + pericardium
CS: resp + GI signs, cardiac + neuro
weimaraners, cocker spaniels, DLH, himalayans
Dx: rads or US, enlarged cardiac silhouette, dorsal deviation trachea
Sx: abs, ventral midline abdominal approach, close defect w/ simple continuous
Penetrating chest wound
dont remove object penetrating
stabilize, cover wound w/ sterile dressing until stable + can Sx repair
thoracocentesis/thoracotomy as needed to tx pneumothorax
Flail chest
multiple segmental rib fractures, moves paradoxically w/ chest wall during respiration
Tx: external splint
Pectus excavatum
congenital deformity, inward concavity of sternum
Tx: external splint
Laryngeal paralysis
LARPAR
damaged vagus n. and branches –> failure arytenoids to abduct on inspiration
congenital - bouviers (association w/ cranial tibial m paralysis) or rotties (progressive generalized dz)
acquired - labs - idiopathic polyneuropathy (MC cause)
Dx: 3 view thoracic rads, laryngeal exam
Tx: medical (mild CS) - weight loss, exercise restriction, environmental changes
- Sx = recommended Tx - unilateral arytenoid lateralization to widen rima glottis
complication: aspiration pneumonia esp if were to do bilateral Sx
whistling noise due to decreased airflow through larynx
stridor
Tracheal collapse
Sx: external prosthetic tracheal rings for cervical trachea only
intraluminal stent - fluoroscopically or endoscopically placed, cervical + thoracic use, complications (stent fracture or migration)
no tx for collapsed bronchi
Tracheostomy
salvage for untreatable upper airway dz
stoma dec in size 40-50% in most animals so make it big
excessive secretions for weeks post op, no swimming, clip hair as needed, protect from foreign bodies
cats can get mucus plugs –> acute death, Px good for dogs
Tracheal trauma
rupture or necrosis secondary to ET tube, foreign bodies
CS: SQ emphysema, progression to mediastinal emphysema or pneumothorax if severe
Tx: minor - medical management (cage rest, O2, sedatives, thoracocentesis). persistent or worsening dyspnea = Sx needed - tracheal resection + anastomosis, split cartilage technique = least stenosis post op
complications: SQ emphysema, stricture
Diagnosing a nasal disease
CR then rhinos copy + nasopharyngoscopy
Rhinotomy
dorsal - access nasal cavity + sinus
ventral - access ventral cavity + choanae
artery you need to avoid during nasal surgery (risk major hemorrhage)
major palatine aa.
Brachycephalic airway syndrome components + signalment
stenotic nares, elongated soft palate, everted laryngeal saccule (stage 1 collapse) +/- hypo plastic trachea
elongated soft palate - MC component of BAS
laryngeal collapse - stage 1: everted saccule, stage 2: cuneiform cartilage collapse, stage 3: corniculate cartilage collapse
GI comorbidities
2-3y, male > female
Brachycephalic airway syndrome treatment
Staphylectomy - soft palate resection - over shortening = nasal reflux
Stenotic nares - wedge resection, alar wing amputation
Laryngeal collapse - stage 2: partial arytenoidectomy + ventriculochordectomy, stage 3: permanent tracheostomy
Post op - leave ET in, give O2, analgesia, NPO 24h
Comlpications - aspiration pneumonia
will still snore
3 types of incisional biopsies
TRU CUT - any accessible mass, sedation or local anesthetic, maintains structural integrity of tissue
PUNCH - >6mm, not for hypodermic masses (undetected hemorrhage)
WEDGE - ulcerated or necrotic tumors or deeply located masses, entire Bx tract removed at later dte
Classification of surgical margins for tumors
Enneking
intralesional, marginal, wide, radical
2 methods of surgical margins for mast cell tumors
Fulcher - circle tumor then measure 1, 2 and 3cm, gen rule = 3cm + 2 fascial plane deep
Pratschke - Modified proportional - widest diameter of tumor = lateral margin unless >4cm use 4cm, 1 fascial plane deep
Processing/Preparation of tumor for submisson
ink all cut surfaces but not skin prior to bread loafing + formalin
Davidson dye = yellow or black
tissue: formalin = 1:10
holding layer of the stomach
submucosa
closure of the stomach
2 layer closure
traditional - double inverting Cushing (serosa, muscularis, submucosa) oversewn w/ lembert (serosa, muscularis)
Alternate - simple continuous (mucosa) oversewn w/ Cushing or lembert (serosa, muscularis, submucosa)
Assessment of gastric viability (subjective)
gastric wall thickening - slip, serosal surface colour, peristalsis, capillary perfusion,
Gastric foreign bodies
MC indication for gastrotomy, young > old, pica predisposed by Fe def
CS: vomit, lethargy, abdominal pain
Dx: labs, rads, endoscopy
Tx: fluids, monitor (serial rads), induce vomiting (apomorphine in dogs, xylazine in cats), endoscopy. Gastrotomy, lavage w/ warm sterile saline, post op - give food/water w/in 12h, fluids
Benign gastric outflow obstruction
congenital pyloric stenosis
- hypertrophy of circular mm, brachycephalics, CS at weaning
CS: vomiting
Dx: rads, contrast rads - beak or apple core
Tx: pyloromyotomy - Fredet Ramstedt procedure (only for congenital stenosis), incision through mucosa + muscularis only
Transverse pyloroplasty - Heineke-Mikulicz procedure, full thickness incision, suture transversely
Phycomycosis
severe inflammation, infiltrative lesion, intense fibrotic rxn. transmural thickening
gulf coast states
CS: vomiting, diarrhea, palpable mass, weight loss
Dx: ELISA for antibodies, Histopath - eosinophilic pyogranulomatous infection
Tx: wide Sx excision, medical Tx ineffective
Px: guarded to poor
Chronic Hypertrophic Pyloric Gastropathy
acquired mucosal + muscular hypertrophy, small breeds, males, older
unknown cause, maybe inc gastrin secretion, acute stress, inflammatory dz, trauma
CS: intermittent vomiting, looks like congenital pyloric stenosis, look at signalment
Dx: endoscopy - mucosal hypertrophy, US - looks at thickening, muscularis <4mm, pyloric wall <9mm
Grade 1 - muscular hypertrophy
Grade 2 - mucosal hyperplasia w/ glandular cyst dilation
Grade 3 - both
Tx: Y-U Advancement pyloroplasty or Bilroth I (gastroduodenostomy)
Px: good
Y-U advancement pyloroplasty
single pedicle advancement from antrum across pylorus, inc diameter of pylorus, access to excise hypertrophied mucosa
potential necrosis of flap tip –> make sure a U not a V
Bilroth I (Gastroduodenostomy)
remove portion of pylorus + put stomach + duodenum back together, removes pyloric sphincter
can remove all dz tissue, technically more demanding, inc risk for dumping syndrome + reflex gastritis
Billroth II (Gastroenterostomy)
partial gastrectomy then gastroenterostomy
for extensive gastric resection making gastroduodenostomy impossible
Complications
- alkaline gastritis
- blind loop syndrome
- marginal ulceration of jejunal mucosa
drug of choice as prophylactic antibiotic in intestinal surgery
Cefazolin
What stitch helps with everted mucosa? (small intestinal surgery lecture)
modified gambie
Small intestinal obstruction
proximal - acute/severe signs, persistent vomiting, gastric secretions
distal - vague, intermittent anorexia, lethargy, occasional vomiting
Dx: CS, Hx, rads
Tx: complete abdominal exploratory, removal through enterotomy aboral (distal) to foreign body
resection + anastomosis if non viable
Linear foreign bodies
cats
CS: vomiting, depression, abdominal pain, palpable bunching of intestines, check under tongue
Tx: remove from base of tongue or gastrotomy, examine mesenteric border of intestines for perfs
Intussusception
Dx: rads, US - target lesion, colonoscopy
Tx: Sx - exploratory celiotomy, manual reduction (gentle), resection + anastomosis, enteroplication
Mesenteric volvulus
rare, often fatal, intestines twist on mesenteric axis, GSD
Tx: rapid fluid resuscitation + immediate abdominal exploratory, derotation + resection, segmental w/o derotation better (reperfusion injury)
Megacolon
cats > dogs
congenital - ganglionic distal colonic segment - absence of inhibitory neurons, functional obstruction
Neuro - lumbosacral dz, key Gaskell (feline progressive dysautonomia), sacral spinal cord deformity (manx)
Pelvic trauma, obstructive, idiopathic
Tx: medical - diet, hydration, enema, prokinetics (cisapride), stool softener (lactulose)
Sx - colectomy, preserve ileocecal valve
post op complications day 3-5, not day 1
Rectal prolapse
probe test to differentiate from intussusception (sx emergency)
Tx: underlying cause, reduce + purse string, amputate if non-viable, colopexy if recurrent
Perianal fistula
GSD, immune mediated dz
CS: painful, perianal draining, fistulous tracts
Tx: diet, cyclosporine +/- ketoconazole, glucocorticoids, tacrolimus, azothioprine, metronidazole
Rectal adenoma
CS: hematochezia, tenesmus/dyschezia, visible mass
most in distal rectum
Dx: rectal palpation, direct observation, Bx
Tx: Sx excision - transanal, dorsal approach
Colorectal adenocarcinoma
50% abdominal
Sx approaches
anal - lesions of caudal rectum or anal canal, epidural block, caudal 4-6cm
dorsal - midrectum but not anal canal
rectal pull through - distal colonic or mid rectal lesion not approachable through abdomen
Anal sac Disease
anal impaction, sacculitis, abscess
common in small dogs
Tx: medically until inflammation resolves
closed anal sacculectomy or open anal sacculectomy
Perianal gland adenoma/adenocarcinoma
male intact, benign masses
castration + resection to tx
Px good if benign, guarded to poor if malignant
Anal sac tumors - apocrine gland adenocarcinoma
paraneoplastic hypercalcemia, PU/PD, renal failure
Gastric displacement
clockwise = MC, torsion <180, volvulus >180
pylorus moves along ventral abdominal wall to L side, stomach covered by omentum
counterclockwise = rare, <90, Hx chronic GI signs, stomach not covered by omentum
Gastric Dilation-Volvulus
CS: acute restlessness, hyper salivation, praying posture, vomiting, non-productive retching, weakness, collapse
Dx: PE, signalment, blood
Tx: initial stabilization - aggressive fluid tx (stabilize CV, renal + resp systems), Gastric decompression - orogastric intubation
- rads R lateral, Sx as soon as stabilized
Sx management of GDV
1) gastric repositioning - decompress stomach if still distended
2) assess gastric viability
3) evaluate spleen
4) gastropexy (doesnt prevent dilation but reduces risk of volvulus to 4%)
Methods: incisional, belt loop, circumcostal (strongest, around rib), laparoscopic assisted
Prophylactic Gastropexy for GDV
breed risk, risk factors, owner request
doesn’t prevent dilation
Surgical anatomy of the liver
central division - gall bladder
right division - blood supply
Liver trauma
CS: acute blood loss signs
Tx: ligate severed vessels, partial hepatectomy, Pringle maneuver - close to hilus = Sx needed
Bile duct stenting
relieve obstruction d/t extraluminal compression
temporarily divert bile after suturing bile duct
Partial lobectomy of liver
Bx, neoplasia, trauma, abscess, cyst
parenchymal fracture + ligation - most blood loss, overlapping suture, stapling technique, surgities
Cholecystitis/cholangiohepatitis
rupture = septic peritonitis
Tx: medically if not ruptured, Sx assess extrahepatic billiary tree, cholecystectomy
Biliary mucocele
older, small dogs, shelties + cocker spaniels
hyperplasia of mucus secreting cells + excessive secretion, accumulation of inspissated bile, over distension –> rupture
CS: none, V/D, lethargy, icterus, PU/PD, pain, fever
Dx: inc ALP, ALT, GGT, Tbilli
US - enlarged gallbladder w/ immobile echogenic bile, KIWI sign
Tx: cholecystectomy, duodenotomy w/ catheterization of bile duct
Biliary diversion
irreparable damage to common bile duct
cholecystoduodenostomy - stoma 2.5-3cm
Bile peritonitis
Dx: abdominal effusion - positive if fluid bilirubin >2x serum bilirubin
Px poor if infected bile = septic peritonitis
2 abdominal organs not filtered by liver
kidney and adrenals
Extrahepatic portal systemic shunts
small dogs, cats
veins that should join portal vein enter caudal vena cava or azygous vein, left gastric vein + splenic vein MC involved
anything entering caudal vena cava cranial to phrenicoabdominal = abnormal, likely shunting vessel
intrahepatic portal systemic shunts
large breeds
patent ductus venosus, intrahepatic branches of portal vein enter vena cava or hepatic vein bypassing hepatic parenchyma
Portal vein atresia
no development, affects major pre-hepatic vessels
CS: ascites, hypoproteinemia, portal hypertension (not systemic)
Tx: no Sx, only medical management
Portal vein hypoplasia
microvascular shunting w/in the liver
middle aged dog shows up w/ “drug sensitivity”
Dx: mild inc bile acids, protein C >70%, nuclear scintigraphy - shunt fraction near normal (vs PSS >70%)
Tx: Medical management
Multiple extrahepatic PSS
secondary to dz that cause portal hypertension, secondary to macrovascular shunt ligation, cirrhosis, non-cirrhotic portal hypertension
small vessels open up bc liver can’t handle blood flow, vestigial embryonic communications that can open up to prevent lethal hypertension from developing, form around kidneys
Macrovascular shunt
CS: general - poor growth, weight loss, drug intolerance. neuro - d/t hepatic encephalopathy, GI: anorexia, VD, urinary: PU/PD, cystitis, urolithiasis
Dx: PE: cats = copper irises, ammonium biurate crystals, NUCLEAR scintigraphy = noninvasive method, but doesn’t tell you which type of microvascular shunt, CR angiography, portography – invasive, not commonly performed
Tx: diet, lactulose, antibiotics, seizure control, control parasites
Max change in portal pressures
9-10cmH2O
Spleen attached to stomach via
gastrosplenic ligament
aberrant non-pathologies of spleen
siderotic plaques (Ca/Fe deposits), ectopic splenic tissue, accessory spleen
Splenic torsion
GDV, large breeds
CS: acute abdomen, pain, abdominal distension, dysarrhythmias. chronic - vague intermittent signs
Dx: US - mottled/diffuse hypo echoic areas, no flow in splenic vessels
Tx: exploratory laparotomy, splenectomy, gastropexy GDV breeds - dont deteriorate spleen prior to splenectomy
neoplasia not a cause
Arrhythmias - ventricular
arrhythmias + GDV
ventricular d/t ischemia, electrolyte abnormalities, etc
Tx: if Vtach w/ rate >180-190, lidocaine bolus or CRI
Diffuse nodular splenic hyperplasia
immune stimulation (tick dz) or splenic hyperactivity (IMHA) hyperplasia = sites of extra medullary hematopoiesis
Tx of splenic traum
commpression bandage, supportive care, partial splenectomy unless at risk breeds
Splenic neoplasia
dogs = hemangiosarcoma, cats = MST
rule of 2/3 - 2/3 dogs w/ splenic mass will have malignancy and 2/3 of malignancies will be HSA
small breeds, wheaten terriers
Px: poor, nearly all microscopic metastasis at time of Dx
Sx = 1-3m, Sx + chemo = 5-6m, Dx + chemo + immune tx = 425d if stage 1, no effect if stage 2
Tx: C-versicolor, eBAT
Complete splenectomy
1) individual ligation of hilarity vessels - preserve branches to pancreas + stomach, time consuming to do but less risk PO hemorrhage, isolate + double ligate vessels at hilus, preferred if anatomical distortion of vasculature
2) ligation of splenic + short gastric aa w/o compromising blood glow to greater curvature of stomach, dec Sx time, inc risk major hemorrhage, preserves branch to L limb of pancreas
Islet of langerhans cells
a - glucagon
b - insulin (60-75% islet cells)
d - somatostatin
f - pancreatic polypeptide
Pancreatic pseudocyst
collections of secretions + debris w/in fibrous sac or wall of granulation tissue, lacks epithelial wall so not true cyst
middle aged dogs
CS: asymptomatic, anorexia, vomiting
Dx: US TOC
Tx: percutaneous aspiration, resection if clinically ill
Surgical techniques of the pancreas
Surgical Bx - guillotine technique, if diffuse dz present, sample distal aspect, R limb easiest to access, procure multiple
Partial pancreatectomy - tumor removal, excise omentum + capsule, dissect between lobules to isolate vessels + ducts in portion of gland to be removed, hemoclips or bipolar cautery best, if remaining duct patent can remove 80% pancreas
Pancreatic abscess
secondary bouts of pancreatitis, inflammation + fibrosis d/t escaped enzymes into surrounding tissue
CS: variable, anorexia, depression, V/D, icterus, pyrexia, palpable mass
Dx: rads - ascites + peritonitis, hyperbilirubimemmia, elevated liver enzymes d/t EHBO
Tx: resect, debride, drain, omentalize
Px: guarded in dog
Exocrine pancreatic adenocarcinoma
malignant, invade locally, metastasis 50-78% at Dx
CS: vomiting, pain, weight loss, EHBO
Tx: Sx if possible, 75% feline = diffuse
Px poor, <7d cats
Insulinoma
B cells in islets secrete insulin despite hypoglycaemia
90% malignant
CS: weakness, seizures, polyneuropathy
Dx: Whipple’s triad - CS assoc w/ hypoglycaemia, fasting blood plc <40mg/dl, relief of neuro signs w/ feeding
insulin >70
Tx: small frequent meals, glucocorticoids, oral hypoglycaemic agents (diazocide), partial pancreatectomy = gold standard
Gastrinoma
rare, highly. malignant, APUD cells in pancreas produce excess gastrin = duodenal ulceration
Zollinger Ellison syndrome - gastric acid hyper secretion
Dx: serum gastrin levels
Px: poor
Classification of peritonitis
primary - spontaneous inflammation in absence of intraperitoneal source, hematogenous/lymphogenous spread, bacterial migration from GIT - gram+, monobacterial
secondary - from underlying primary dz process, common, bowel leakage, neoplastic invasion, pancreatitis - gram-, polymicrobial
Sx not done for primary but requisite for secondary
Septic peritonitis
GI origin, E. coli or bacterioides fragillus (synergistic together)
ruptured GB mucocele, pancreatitis, pyometra, BDLD bit etc
CS: hyper dynamic then hypo dynamic, cats have no pain on palpation + relative bradycardia
Dx: abdominal US + cytology gold
peritoneal [glc] effusion 20 pts < serum [glc]
effusion [lactate] 2 its > serum [lactate]
creatine [ ] > serum creatinine [ ]
fluid [bili] 2.5x > serum [bili]
Tx of septic peritonitis
antimicrobials based on cytology + gram stain, 4 quadrant. go to = IV ampicillin, baytril, metronidazole (if use amino glycoside instead of baytril can potentiate renal problems)
Retained deciduous teeth
failure of primary tooth’s root to undergo resorption
toy breeds + cats
all teeth erupt lingual to deciduous except maxillary canines which erupt rostral
Crowding of teeth
brachycephalics
maxillary 3rd premolars MC
Shelf on palatal surface of maxillary incisors where mandibular incisors occlude
cingulum
Classes of malocclusions
1 - neutroclusion, base narrow canines, rostral cross bite, caudal cross bite
2 - mandibular brachygnathism, overshot, parrot mouth
3 - mandibular mesiocclusion, mandibular prognathism, undershot, level bite
4 - wry bite
Dentigerous cyst
fluid filled cyst surrounding crown of uninterrupted tooth resulting from persistence of portions of enamel forming epithelium
CS: missing teeth, swelling (blue hue), pain
Rx: extract impacted tooth, remove lining of cyst
Enamel hypoplasia
d/t high fevers, distemper, periapical inflammation or trauma
Attrition vs abrasion (dental)
attrition - pathologic wearing d/t contact w/ opposite tooth
abrasion - abnormal contact w/ crown surface by foreign object
Draining tract associated w/ teeth
parulis
MC tooth fractured
upper 4th premolar
Tx of tooth fractures
Vital pulpotomy - young animals <18-24m, sooner = better
Root canal - older mature animals >24m, maintains tooth function but tooth is dead
Tooth luxation/avulsion
true emergency if you want to save tooth, after 30m success goes down, keep tooth in milk
Tooth resorption
lesions are not cavities
Type 1 - periodontal dz, classic neck lesions at cement-enamel junction, gingivitis, painful
Type 2 - minimal or no evidence of periodontal dz, resorption of roots, periodontal ligament gone
Type 3 - multi rooted, type I or II
CS: drop food, chatter, anorexia
Tx: type 1 = extract tooth, type 2 = amputate crown
Gingivostomatitis
maxillary teeth caudal to canines MC
extract teeth sooner = better
Periodontal dz -
MC oral dz #1 cause tooth loss calculus, gingivitis, periodontitis
normal sulcus depth
cats - 0-1mm, dogs - 1-3mm
intraoral splint
composite resin/acrylics - preferred, normothermic curing, easy application
acrylics - exothermic curing
Lip avulsion
shearing trauma along mucogingival line, lower lip MC
what = failure in regards to suturing gingiva
tension
highest incidence of fracture in cat mouth
symphysis and ramus of mandible
