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
