SA Surgery Flashcards
Types of wound closure?
Primary closure
Delayed primary closure (1-5d after wound, daily debridement/lavage/bandaging), - e.g. if too much tension
Secondary closure (>5d after wound) - for contaminated/dirty wounds
Aims of skin reconstruction?
Square skin edges Accurate apposition No overlapping Slight eversion of wound edges Follow Halsted's principles
When is skin undermined and advanced for a wound? What does it do? Methods?
Indicated when wound too large for closure using tension relieving sutures but too small for a flap
Frees skin from s/c attachments
Allows use of skin elasticity to close defect
Blunt (scalpel hands,e scissors) or sharp (scalpel, scissors)
Maintain vascular supply
Undermine deep to panniculus layer where present (if not, undermine in loose areolar fascia deep to dermis)
Walking sutures to pulls kin in and close dead space (not too many as will damage sub-dermal plexus)
Tension relieving methods for wounds?
Vertical mattress sutures
Alternating smaller and larger simple interrupted sutures - good for not affecting blood supply as sutures perpendicular to wound edge
Horizontal mattress sutures
Far, near, near, far sutures
Multiple punctate relaxing incisions (parallel to wound edge to relieve tension) - not good for cosmetic look
Z shaped incisions - good for burns over elbows etc
How to cosmetically close a wound that has one wound edge longer than the other?
Suture as normal but place further apart on longer edge and closer together on shorter edge
Or place first suture half way along wound, then next sutures half way along 2 remaining sections and repeat
How to close a rectangular wound cosmetically?
Place first sutures at corners and continue until sutures come together and then go along line
How to close a square shaped wound?
Suture from corners and continue to middle to result in cross shape
How to cut around a tumour near a structure that needs avoiding?
M-plasty:
Fusiform shape as normal on side away from structure
On side near structure to be avoided, do a back cut away from structure and suture from fusiform side to back cut and then from 2 corners to meet middle as Y shape
What are cutaneous pedicle grafts?
“Skin flaps”
Portions of skin and s/c tissue moved from one area to another
Best on head, neck and trunk (most skin)
Good cosmetic results - hair growth
Skin flap planning?
Initially larger than the defect to be covered
Avoid narrow pedicles
Undermine below the panniculus
Use fine suture material and initial tacking sutures to ensure flap conforms well to recipient bed
Ensure recipient bed is free of infection, contamination and necrotic tissue - either a fresh surgical wound or healthy granulation tissue bed
Don’t exceed a length:width ratio of 3:1 for unipedicle flaps and 4:1 bipedicle flaps
When does skin flap revascularisation occur and how is division done if needed?
Collateral supply develops in 7-10d Many flaps won't need division Initially divide: - direct flaps 10-14d post-transfer - tubed pedicles > 1 month postop - can partially divide tubed pedicles 2 weeks postop
Why may skin flaps fail?
Arterial/venous occlusion - thrombi, torsion (don’t rotate flaps by >180 degrees), stretching
Tension - direct on flap, from haematoma/seroma
Infection
How to assess skin flap health?
Colour - unreliable Temperature Sensation - unreliable Hair growth Objective measures - fluorescein (not fluorescent areas often dehisce)
What to do if a skin flap is dying?
Ointments
Debridement followed by:
- open wound management +/- secondary closure
- another flap?
Hyperbaric oxygen or hypothermia (cold packing for 10-15mins few times/day)
Types of free skin grafts?
Full thickness Split thickness Pinch Punch Strip Mesh
How do skin grafts survive?
Revascularise from graft bed 3 steps: - plasmatic imbibition (days 1-3) - inosculation (day 3 onwards) - vessel ingrowth (up to 1-2 weeks)
Factors affecting skin graft survival?
Graft-bed contact (serums/haematomas) Movement (body movement) Host factors Infection Bed must be a fresh surgical wound or healthy granulation bed
Types of drains?
Passive drains - drain along side of tube by capillary action e.g. penrose tube
Active drains - can make from syringe and extension from giving set, holes in tube to allow fluid into tube for drainage, or butterfly catheter with vacutainer for negative pressure, more efficient than passive and pressure helps close dead space
When to remove a surgical drain?
Drains incite a foreign body reaction so will always be some fluid present
Remove when a consistent, small volume of serosanguineous fluid is produced
Halsted’s principles of surgery?
Gentle tissue handling Meticulous haemostasis Preservation of blood supply Strict asepsis Minimal tension Accurate tissue apposition Obliteration of dead space
How to best view right dorsal abdomen?
Duodenal dam manoeuvre
= use duodenum and duodenal mesentery to pull over to left side
How to best view left dorsal abdomen?
Colonic dam manoeuvre
How can you prevent blood loss from the liver during surgery?
Pringle manoeuvre:
- temporary occlusion of hepatic blood flow (up to 15 mins)
- more complete occlusion also possible with clamps/ligation combination
How to assess intestinal viability?
Subjective criteria: - colour - presence of arterial pulses - ongoing peristalsis Objective criteria: - pulse oximetry - doppler ultrasound - fluorescein dye and Woods lamp
Which area of the GIT has a resident Clostridia population?
Liver
Which antibiotics may be used as prophylaxis for GI surgery?
Clavulanate-amoxicillin for general prophylaxis
Metronidazole for anaerobes
Amoxicillin and cefazolin actively excreted in bile
Which 2 areas can tension be a problem with GI surgery?
Oesophagus
Colon during subtotal colectomy
How is accurate tissue apposition achieved with oesophagectomy and enterectomy?
End-to-end appositional anastomosis
Why does the oesophagus heal more poorly after surgery that the rest of the GI tract?
Incomplete serosal covering
Poor vascularity
Tension and motion
Suture material used for GIT?
1.5 to 2 metric (up to 3 in stomach) Monofilament absorbable: - Polydioxanone (PDS) - Polyglyconate (Maxon) - Poliglecaprone 25 (Monocryl) Avoid multifilament - wicking, acts as nidus for bacterial growth
What suture patterns are used for GIT surgery?
Must incorporate tough submucosa
Appositional patterns are best - easy and rapid, preserve blood supply, maintain luminal diameter, minimal adhesions
Continuous best - less mucosal eversion, less adhesions, better submucosal apposition
Why is side-to-side anastomosis not done for GIT surgery?
Associated with pouch formation, dilation and rupture
Why is side-to-side anastomosis not done for GIT surgery?
Associated with pouch formation, dilation and rupture
Pathophysiology of peritonitis?
Hypovolaemia Metabolic acidosis Electrolyte imbalances Endotoxic shock Death
Clinical signs of peritonitis?
Depression Anorexia Vomiting Abdominal pain and distension (boarding, praying position) Ileus Pyrexia Shock
Diagnostic tests for peritonitis?
Radiography - generalised loss of contrast - free gas in abdomen Haematology - neutrophilia and left shift - sometimes degenerative Serum biochemistry - azotaemia - hyproglycaemia Abdominal paracentesis - degenerate neutrophils - free and/or intracellular bacteria - compare lactate and glucose to serum
Treatment for peritonitis?
Fluid therapy
Broad spectrum antibacterials - later based on c+s
Correct primary cause - exploratory coeliotomy
Copious peritoneal lavage
When is short bowel syndrome seen?
Occurs after removal of >80% of SI
Long term problems with ill thrift and chronic diarrhoea
Medical management
Prognosis poor
What is ileus? Cause? What happens? Treatment?
Inadequate peristalsis of whole GIT leading to functional obstruction
Due to vagosympathetic reflex
Whole gut becomes distended and gas or fluid filled
Treat by correction of underlying disease, supportive therapy (fluids, metaclopramide)
What is usually the best surgical approach for access to the oesophagus?
Ventral cervical midline for oesophagus to level of 2nd rib
Right intercostal thoracotomy at level of lesion
Difference between coeliotomy and laparotomy?
Coelitomy - ventral midline incision into abdomen
Laparotomy - flank incision into abdomen
Sutures for closure of coioltomy?
Single layer of simple continuous appositional in external sheath of recess abdominis
5-10mm from edge, 3-12mm apart
Why is a laparotomy not usually used for GIT surgery?
Restricted exposure
More traumatic
What primary and secondary cleft palate?
Primary - failure to fuse of lips and premaxilla
Secondary - failure to fuse of hard and soft palates
Complications with secondary cleft palate?
Dehiscence
May recur as animal grows
Some animals have chronic rhinitis
Treatment for benign oral neoplasia of dogs and cats?
Dogs - wide local excision
Cats - wide local excision, radiotherapy
Treatment for malignant oral neoplasias of dogs?
Malignant melanoma - wide local excision and radiotherapy
Squamous cell carcinoma - wide local excision if possible, radiotherapy
Fibrosarcoma - wide local excision and radiotherapy
Treatment for oral neoplasias in cats?
Squamous cell carcinoma - surgery, radiotherapy and chemotherapy combined
Fibrosarcoma - wide local excision, adjunctive radio/chemotherapy may be of benefit
Melanomata - local radiotherapy and chemotherapy
What can cause salivary mucocoele?
Commonest disease of canine salivary glands
Sublingual gland most often affected
Due to trauma, sialolith, neoplasia, foreign body, iatrogenic: most idiopathic
Clinical signs of salivary mucocoele?
Painless fluctuant swelling
Dysphagia, ptyalism, blood in saliva with sublingual mucocoeles
Inspiratory stridor, coughing or respiratory distress with pharyngeal mucocoeles
Post op care for oesophageal surgery?
Thoracotomy care
Nil by mouth for 24-48h
Water and soft food 5-7d then gradual return to normal diet
Monitor for dehiscence - TPR, lung sounds, general attitude
When is surgery required for oesophageal foreign bodies? Complications after removal?
Surgery if large perforations/fistulae or can't remove endoscopically Complications: - oesophagitis - dehiscence and infection, fistula Stricture - vascular injury
What is PRAA?
Persistent right aortic arch
Retained right aortic arch forms aorta, left aortic arch forms left subclavian artery = mirror image or normal
Indications for partial gastrectomy?
Necrosis e.g. in GDV
Neoplasia
Ulceration
Factors associated with GDV?
Breed predisposition in purebred large dogs - Great Dane, Irish Setter etc
Also deep chested breeds
STRESS is big risk factor (-> panting -> aerophagia) - hospitalisation therefore big risk factor too
Diet Feeding regime Overeating/overdrinking Defective eructation/vomiting Aerophagia Exercise Defective gastric motility Defective gastric fermentation
Pathophysiology of GDV?
Gas and fluid accumulates in stomach Not removed by eructation Stomach rotates (usually clockwise) 180 degrees commonest (90-360 degrees) In clockwise, pylorus comes to lie in left ventral abdomen
Treatment for GDV?
2 immediate priorities:
Shock fluid therapy
Decompress stomach:
- stomach tube
- or needle paracentesis (identify gas-filled fundus by percussion)
- temporary gastrostomy
All cases require gastropexy to prevent subsequent torsion/volvulus
- will not prevent tympany/dilatation
- big incision (xiphoid to pubis)
- fixes pylorus to right abdominal wall
- derotate stomach by gentle traction on pylorus first
Splenic congestion common (vessels in gastrosplenic ligament go to greater curvature and spleen - occlusion leads to necrosis)
- generally resolves when stomach repositioned
- splenectomy not indicated if no thrombi and no splenic torsion
- if looks bad e.g. black after 5 mins of putting back in place then splenectomy
Gastrectomy
- 10% cases show some gastric necrosis
- assess stomach wall viability (red/purple = congestion +/- intramural haemorrhage, usually recovers, grey/greenish = nonviable)
- active bleeding
- pulses
- thickness and pliability (thinning of wall = necrosis)
- resect all nonviable tissue
- increased mortality if required (poor prognostic indicator)
Post op care for GDV surgery?
Fluids
Monitor ECG for 24h post (VPCs common)
Monitor electrolytes
Nil by mouth 24-48h then water and small amounts of food
Gastric mucosal protectants - sucralfate, antacids, omeprazole
Metaclopramide if vomiting (ileus)
In future may be beneficial to feed small frequent meals and avoid exercise after meals
Analgesia:
- avoid NSAIDs as hypovolaemia so AKI risk
- paracetamol
Causes of gastric outflow obstructions? Treatment?
Neoplasia Pyloric stenosis Hypertrophic gastritis Pyloric muscular hypertrophy/dysfunction Treat with pyloroplasty procedure
What are the Billroth I and II procedures?
Gastroduodenostomy and gastrojejunostomy
Allow resection of large amount of distal stomach and pylorus e.g. in neoplasia
Choice based on amount to be resected and resulting tension on tissues
Billroth II is technically complex - high incidence of complications, consider referral
Treatment for linear foreign bodies?
Don’t just pull it -> gastric perforations!
Conservative management
- if FB fixed under tongue and can be cut, no evidence of peritonitis
- FB will often pass ok (3d)
Surgery
- if FB not fixed at tongue or signs of peritonitis
Causes of rectal prolapses?
Persistent faecal tenesmus
Defects in rectal/anal support
Denervation of anal sphincter
Treatment and post op care of rectal prolapses?
Diagnose and treat underlying disease Reduce prolapse Surgical correction - purse-string suture for 1-5d - colopexy - resection and anastomosis Post op care: - stool softeners - low bulk diet - sedation to reduce tenesmus
What are perianal fistulas? Aetiology? Which breeds are predisposed?
Also known as anal furunculosis Chronic, ulcerative fistulous tracts surrounding anus, up to 360 degrees involvement Aetiology: - anal sac/circumanal gland infection - faecoliths in anal crypts - autoimmune (most likely) - tubuloalveolar glands hydradenitis GSDs, labradors, setters and collies
Clinical signs and treatment of perianal fistulas?
Clinical signs: - tenesmus - pruritus - fistulae/sinus tracts around anus Treatment - medical therapy best - ciclosporine - surgical excision - messy and complicated, high recurrence rate
What is the functional reserve of the hepatobiliary system?
70-80%
So can remove relatively large amounts of tissue with few ill effects
surgical biopsy method for liver?
Guillotine method for peripheral lesions
Trucut or punch biopsy for central lesions
Indications for partial liver lobectomy?
Neoplasia
Abscessation
Trauma
Types of portosystemic shunts?
Congenital extra hepatic shunts (<1y) - usually single vessel - commoner in small breeds Congenital intrahepatic shunts (<1y) - failure of ductus venosus to close - portocaval or portohepatic anastomoses - commoner in larger breeds Acquired extra hepatic shunts (1-7y) - multiple, secondary to portal hypertension - microvascular connections between portal vein and systemic veins hypertrophy and become functional
Clinical presentation of portosystemic shunts?
Poor growth Anorexia Depression Vomiting PUPD Ptylamis (esp in cats) Behavioural changes Urate urolithiasis Hepatic encephalopathy - ataxia - weakness - head pressing - circling - depression - seizures or coma - often worse after high protein meals Small liver
Diagnosis of portosystemic shunts?
History and clinical signs
Radiographs - small liver, abnormal positive contrast program
Ultrasonography - directly visualise shunt vessel
Scintigraphy
Microcytosis, mild non regenerative anaemia, poikilocytosis, low BUN, hypoalbuminaemia, occasionally increased ALT/AST/ALKP, elevated pre and postprandial bile acids
medical management of portosystemic shunts?
Highly digestible protein diet
Antibiotics to reduce enteric flora - neomycin, metronidazole, ampicillin
Lactulose - synthetic disaccharide, traps ammonia in gut, reduces ammonia production
Median survival time 836d
Surgical management of portosystemic shunts?
Attenuation of shunting vessel
Ligation - risk of portal hypertension
Ameroid constrictor placement
- absorb water gradually and occlude shunt over several weeks
Cellophane banding
- cellophane causes inflammatory reaction, fibrosis and gradual shunt attenuation
Post op care for portosystemic shunts?
Medical management until shunt attenuates and liver regenerates
Observe for portal hypertension - abdominal swelling (ascites) and pain, bloody diarrhoea, endotoxic shock, death
Seizures may occur up to 72h post, control with anticonvulsants
Prognosis of portosystemic shunts?
Greater risk of complications with ligation compared to aneroid placement or cellophane banding
Longterm followup data lacking
Extrahepatic shunt better prognosis in dogs
60% 1yr and 55% 4yr survival in cats
Bile flow diversion?
Obstruction of common bile duct
Trauma to common bile duct
Cholecystoduodenostomy or cholecystojejunostomy - choice based on whether gall bladder and duodenum can be apposed without tension (Cholecystoduodenostomy best if possible)
Partial pancreatectomy?
Handle pancreas gently – pancreatitis!
Simple encircling ligature for peripheral lesions
Blunt dissection between lobules for central or peripheral lesions - individually ligate ducts and vessels supplying tissue to be excised
Method for pancreatic biopsy?
Trucut needle
FNA
Shave off affected tissue with a scalpel
Define a hernia?
The protrusion of an organ or part of an organ through a defect in the wall of the anatomical cavity in which it lies
How are hernias classified?
Anatomical site Congenital or acquired Reducible, incarcerated, strangulated Type of herniated tissue External or internal
Aetiology of hernias?
Trauma
Surgical intervention
Genetic - familial inheritance
Problems with hernias (pathophysiology)?
Alteration in function of body cavities (space occupying defect):
- e.g. altered gait (inguinal)
- e.g. cardiorespiratory compromise (diaphragmatic, PPDH)
Alteration in function of hernial contents:
- obstruction of hollow viscous
- strangulation of herbal contents (vascular obstruction, venous-capillary-arteral-tissue death-organ rupture=etc)
- GIT: vomiting, obstructive ileum, toxaemia, shock
- bladder: obstructive/post renal azotaemia, dysuria, vomiting
Clinical signs of external herniation?
Swelling in typical location
Usually non painful
Consistency?
If GIT involvement - vomiting, abdominal pain, toxaemia, shock
If bladder/urethral involvement - dysuria, abdominal pain, vomiting, toxaemia, shock
Clinical signs of internal herniation?
No mass seen/palpable
Often clinically silent for months/years
Respiratory - dyspnoea
GIT - vomiting (often intermittent)
Aims of herniorrhaphy?
- Return viable contents to their normal location
- Secure neck of hernia to prevent recurrence
- Obliterate redundant tissue in hernial sac
- Use patient’s own tissues for repair (if possible), sometimes via creation of musculotendinous or fascial flap
- Fascia is slow to heal, choose permanent or slowly absorbed monofilament suture material
- Tension relieving pattern? (cruciate mattress sutures)
- Rarely, prosthetic implants required
Types of umbilical hernias? Assessment?
Congenital - usually obvious at birth, present in older animals secondary to increased abdominal pressure Acquired - excessive traction on umbilical cord at parturition, severing cord too short Assessment: - size? - contents? - reducibility? - other congenital defects? - repair needed?
Types of inguinal hernias? Diagnosis?
Congenital - rare, males poss predisposed (delayed inguinal ring closure associated with testicular descent), sometimes close spontaneously
Acquired - more common, esp mid aged entire bitches
Diagnosis:
- palpate both inguinal rings and reduce hernia
- radiography +/- contrast (catheterise bladder, positive contrast)
- US
- FNA
Differential diagnoses similar to inguinal hernias?
Mammary tumours/cysts Lipoma Abscess Enlarged lymph node Haematoma
How to surgically repair uncomplicated and complicated inguinal hernias?
Uncomplicated:
- incise over lateral aspect of swelling
- blunt dissect to expose hernial sac
- reduce hernial contents
- ligate neck of sac close to inguinal ring and amputate
- reduce inguinal ring by suturing
Complicated:
- caudal midline coeliotomy
- dissect tissues from external rectus fascia to expose both inguinal rings
- hernia repair as before
Advantages of a midline approach for surgical repair of a complicated inguinal hernia?
More familiar anatomy
Doesn’t disturb mammary tissue
Can repair bilateral hernias through one skin incision
Post operative complications of inguinal hernia repair? How to avoid these?
Usual postoperative wound complications plus:
Pain - avoid nerve entrapment
Haematoma - avoid by careful haemostasis and avoid vessels in inguinal ring
Seroma - avoid excessive subcutaneous dissection, close dead space, use drain?
Recurrence
Post op care for inguinal hernia repair?
Rest for 10-20days to allow healing
Gentle lead walking to reduce oedema
Analgesia
What is a scrotal hernia? Clinical signs and diagnosis of scrotal hernias?
Defect in vaginal ring allowing abdominal contents to protrude into vaginal process beside spermatic cord - rare
Usually unilateral
Clinical signs - pain, swelling, organ dysfunction
Diagnosis:
- reduce contents and palpate hernial ring to confirm
- radiography?
- US
Treatment of uncomplicated and complicated scrotal hernias?
Uncomplicated:
- incise over/lateral to inguinal ring
- expose hernial sac and open if necessary
- reduce abdominal contents
- close external inguinal ring
- if castration permitted: open hernial sac, ligate spermatic cord, ligate hernial sac at inguinal ring
- if castration not permitted: reduce size of neck of hernial sac with mattress sutures
Complicated:
- caudal midline coeliotomy and dissect tissues from external rectus fascia to expose both inguinal rings
- en bloc resection and repair of unhealthy tissue as necessary
- closure of inguinal ring
- recommend bilateral castration (reduces recurrence, increased risk of testicular tumours in affected dogs, inherited?)
What is a perineal hernia? When mostly seen? Pathogenesis? Clinical signs?
Failure of muscular pelvic diaphragm to support rectal wall
Pelvic and/or abdominal contents protrude between rectum and pelvic diaphragm (prostate, bladder, omentum, SI)
If bladder, can have retroflexion causing life threatening urethral obstruction)
Most commonly seen in older male entire dogs
Rare in cats and bitches
Pathogenesis:
- muscle atrophy
- hormonal
- myopathies
- prostatic disease?
Clinical signs:
- reducible perineal swelling ventrolateral to anus
- constipation/obstipation
- tenesmus
- dysuria
Diagnosis of perineal hernias?
Rectal examination
Routine haematology/biochemistry and electrolytes (essential if dysuric)
Abdominal radiography - plain, positive contrast cystogram, retrograde urethrogram
Ultrasonography - abdominal, perineal
What to do if retroflexed bladder with a perineal hernia?
Decompress:
- Urethral catheterisation
- Perineal cystocentesis, then attempt urethral catheterisation
Prep for surgical repair of perineal hernia? Post op care?
Empty rectum of faeces
Place anal purse string suture and drape anus out of surgical field
Advise concurrent castration
Poss stage repairs if bilateral disease (rectal prolapse less likely?)
Post op care:
- prior to GA recovery remove purse string suture
- analgesia, antibiosis
- prevent interference with wound
- faecal softeners/modulators (long term) - isogel, actulose
- monitor defaecation and urination
Postop complications of perineal hernia repair?
Rectal prolapse Wound infection Continued defacatory tenesmus Faecal incontinence Atonic bladder following urethral obstruction/bladder retroflexion Recurrence
Causes of traumatic abdominal hernias? Other injuries involved?
Blunt trauma (kicks, RTA, falls)
- usually also other significant injuries
- often widespread crush, rupture or avulsion of abdominal organs
- often orthopaedic injuries
Sharp trauma (bite wounds, gun shot, stabs)
- often tears, lacerations or perforations of other intra-abdominal organs
Evaluate whole patient and stabilise first
Clinical signs of traumatic hernias?
Asymmetry of abdominal contour, bulging mass under skin
Area of greatest swelling may not be site of rupture
Size/consistency of swelling may alter
Diagnosis of traumatic hernias?
Acute hernias often painful with abdominal bruising, indistinct borders, etc
Chronic hernias often non-painful
Contents will reduce into abdomen?
Hernial ring palpable?
Radiography (abdomen AND thorax):
- discontinuous abdominal wall
- organ displacement
- gas filled tubes in subcutaneous tissues
- free abdominal gas (viscus rupture, penetrating injury?)
Treatment for traumatic hernias?
Emergency life support
Normalise cardiopulmonary function
Bandage wounds
Clip and prepare large area to allow extensive surgical exploration if can’t palpate hernial ring
Acute hernias approach via midline coeliotomy, intra-abdominal repair
Assess abdominal organs for injury, especially if acute sharp trauma
Debride devitalised tissue
Choose appropriate sized suture material
Taken generous “bites”
Place sutures in healthy, strong tissues
Appose tissues, don’t crush
Close individual muscle layers separately if possible
Tension relieving suture pattern?
Pre-place sutures, tie sutures in deepest part of wound first
Cause of diaphragmatic hernias/ruptures? Diagnosis?
Mostly traumatic, rarely congenital Often missed initially - becomes chronic Clinical exam - altered auscultation? 'empty abdomen? Radiography Ultrasound
Treatment of a diaphragmatic hernia/rupture?
Acute: stabilise then surgery
- midline cranial coeliotomy (caudal sternotomy rarely required)
Chronic: surgery? (beware of adhesions!)
- midline cranial coeliotomy (sometimes need caudal sternotomy
- be aware of re-expansion pulmonary oedema in recovery
Causes of incisional hernias seen? Problems?
Acquired - following disruption of surgical closure of body cavity
Uncommon in small animals
Severe, life threatening consequences
Acute (occurs within 7 days of surgery)
- increased abdominal pressure (pain, straining, barking, coughing, ascites)
- infection
- chronic steroid treatment
- inappropriate choice and placement of sutures
entrapped fat between wound edges
- poor postoperative care (e.g. vigorous activity, poor wound healing)
Chronic (occurs weeks-years after surgery)
- obesity
- hypoproteinaemia
- chronic steroid treatment
- deep fascial infection
- abdominal distension
Clinical signs of acute incisional hernias?
Oedema/inflammation (ie altered wound healing)
Swelling
Serosanguinous wound discharge
Evisceration
Differential diagnoses for acute incisional hernias?
Seroma Haematoma Abscess Cellulitis Infection Reaction to suture material
Treatment for acute incisional hernias?
Identify and address reason for incisional hernia
Approach via original incision
Debridement of abdominal wall is contra-indicated unless wound edges are devitalised
Consider choice of suture material and size
Take adequate bites (5mm minimum) of strength holding layer
Appropriate postoperative management
What must be done if evisceration of acute incisional hernia?
Aggressive, early treatment
Cover exposed organs with sterile bandage
Elizabethan collar
Pre-operative analgesia, antibiotic and fluid therapy
Lavage exposed tissues with lots of sterile saline
Prepare area for aseptic surgery
Open/extend original wound and assess abdominal viscera
Resect non-viable tissues
Copious abdominal lavage with sterile saline
Close abdomen (open peritoneal drainage?)
Postoperative supportive therapy (analgesia, antibiosis, fluid therapy, etc)
Treatment of chronic incisional hernias?
Overlying tissues generally strong enough to prevent evisceration
Chronic scarring makes identification of tissues difficult
Wound edges may have retracted so insufficient tissue for repair
Debride scar tissue until identify normal tissues
“Loss of domain”
Prosthetic implants?
What is seen with end stage chronic otitis externa?
Irreversible ear canal narrowing External ear canal ossification Concurrent otitis media Peri-aural abscess Tumours
Lateral wall resection for end stage chronic otitis externa - Other name? Criteria for when should be used?
= Zepp’s operation
Needs a normal healthy horizontal canal
Used for small tumours of the lateral vertical wall
(Very limited indication to do this!!)
Vertical canal ablation for end stage chronic otitis externa - Criteria for when should be used? Pre-op prep? What must be done to the bulla? Post-op care?
Needs a normal horizontal canal Used for: - vertical canal neoplasia - stenosis of the vertical canal only - trauma Pre-op prep: - pure opiate and MLK - IV antibiotic - cotton tips to clean inside of vertical canal - pack with iodine ointment - secure anaesthetic circuit Do a lateral bulla osteotomy: - curette bulla to remove all secretory epithelium - lavage with lactated Ringers - swab bulla and wound post lavage Post-op care: - pure opiate for 24h - antibiotics depending on post-op swab culture - remove drain after 24h - meloxicam for 7d - remove sutures in 14d - submit external ear canal and bulla lining for histopath - continue to treat underlying skin disease
Complications of total ear canal ablation (TECA)?
Facial nerve paralysis Haemorrhage Horner's syndrome (damage to sympathetic nerves) Deafness Wound infection Vestibular disease Chronic fistula and abscessation
Why should you take stomach biopsies from halfway between the greater and lesser curvature?
No blood vessels
How to check if intestinal sutures are ‘water-tight’?
Push fluid into section and test, or if not much fluid then inject saline into section
How long to use intra/post-op antibiotics for GIT surgery?
Start at induction for prophylaxis
Can continue for up to 24h if needed
No longer as negative effect on gut flora
Would use therapeutically if found infection on entering abdomen e.g. FB/peritonitis
Should you do a prophylactic gastropexy for all predisposed breeds for GDV risk?
Great Dane only breed shown to benefit
But if were doing another abdominal surgery on a large breed dog, then offer it as an elective gastropexy is easy and GDV worth preventing
Clinical signs of GDV?
Collapse (due to hypovolaemic shock as caudal vena cava compressed, and septic shock)
Unproductive vomiting
Distended abdomen
Hypersalivating as nauseous
Lethargic
Pale mm
Regurgitation of saliva
Diagnostics to perform if suspect GDV? Poor prognostic indicator?
TPR and BP Haematology and biochemistry Electrolytes - high lactate (>10) is poor prognostic indicator (<6 is good) Decompression Radiography ECG - common to get VPCs
Why are VPCs common with GDVs?
Myocardial damage due to toxins and hypokalaemia
Poor prognostic indicators for GDVs?
High lactate (>10) Gastric necrosis
What causes GI pain (e.g. with splenic masses)
Visceral nociceptors are stimulated by: - Inflammation - Ischaemia - Distension of a hollow viscous Distension/stretching of organ capsules Ligament traction Spasm Hypermotility Inflammatory mediators directly stimulate visceral nociceptors in gastric wall etc (e.g. if necrosis)
Risk factors for ileus post-op?
Unnecessary analgesics in patients with pain tolerance with NSAIDs Abdominal surgery Excessive SI manipulation Prolonged nasogastric catheter use Mechanical ventilation Sepsis Shock Trauma SIRS Electrolyte imbalances Etc
What size vessels can electrocautery be used for? How does it work? Disadvantages? Types?
Vessels <1.2mm
Haemostasis by electric current generating heat to cause coagulation
Disadvantages:
- burns
- delayed healing
Monopolar = current from instrument to plate under patient, can cut at same time as haemostasis, not effective if tissue wet
Bipolar = less current, less risk of damage to surrounding tissue, effective on wet surgical field
How does ligature work?
Pressure and thermal energy from a high current
Melts collagen in blood vessels to create a seal
Doesn’t rely on formation of a clot
How long to leave a clamp for mechanical haemostasis?
5 mins minimum - normal clot formation time
Indications for emergency coeliotomy?
Haemoabdomen if PCV same as normal blood (as means haemorrhaging) Septic peritonitis (must have GI rupture if bacteria/organic material on peritoneal tap cytology, or if air in peritoneal cavity on imaging) GDV Foreign body - if segmental dilation on imaging (unlikely if generalised dilated intestines)
