1. Basic Surgical Techniques Flashcards
What is the definition of sterilisation
Elimination of all pathogens, including spores
What is the definition of disinfection
Removal of microorganisms, sometimes doesn’t include the spores
What is the definition of disinfectant
Agent that will destroy microorganisms
What is the theatre cleaning routine
Morning damp dusting - first thing
Between cases - disinfect
At the end of the day - damp dust everything and disinfect
Once a week - Deep clean, swabs taken, hard to reach places
Pre-op prep of the patient
Some form of starvation - can have water
Owner should bathe them before bringing it
Clipping - prior to induction/once induced
Specific surgical prep - e.g. enema if doing lower GIT surgery
What are the 3 theatre styles
First opinion
Referral
Charity
What are the 3 surgical scrub solution options for the patient?
Chlorhexidine
Povidone iodine
Isopropyl alcohol
What concentration and contact time is requires for Chlorhexidine and Povidone iodine
Chlorhexidine - 2% solution for 5 mins
Povidone iodine - 7.5% for 3 mins - good for patients with chlorhexidine sensitivity
Different strengths of scrubbing solutions for oral and ocular cleaning
Oral - 0.1% chlorhexidine
Ocular - 0.2% povodine iodine
What are the 4 types of draping a patient?
- Plain 4 corner drape
- Draping a limb
- Fenestrated drape
- Adhesive barrier drape
Definition of a bacterial infection
Bacterial infection is defined as having more than 10^5 bacteria per gram of tissue
What is a surgical site infection (SSI), and what are the subtypes?
Infections of the tissues, organs, or spaces exposed by surgeons during performance of an invasive procedure
Incisional infection - superficial or deep
Organ/space infection
What are the 4 classifications of surgical wounds
- clean
- clean-contaminated
- contaminated
- dirty
Describe a ‘clean’ surgical wound and provide 3 examples
Non-traumatic, non-inflamed operative wound
Respiratory, GI, genitourinary and oro-pharyngeal tracts are NOT entered
Examples - ex lap, elective neuter, total hip replacement
Describe a ‘clean-contaminated’ surgical wound and provide 3 examples
Operative wound
Respiratory, GI, genitourinary tracts ARE entered but under controlled conditions
OR an otherwise clean wound with a drain placed
Examples - bronchoscopy, cholecystectomy, enterotomy
Describe a ‘contaminated’ surgical wound and provide 2 examples
Open, fresh or accidental wounds
Procedures where GI contents or infected urine is spilled
A major break in aseptic technique
Examples - cystotomy with spillage of infected urine, open cardiac massage for CPR
Describe a ‘dirty’ surgical wound and provide 3 examples
Old, traumatic wounds with purulent discharge, devitalised tissue or foreign bodies
Procedure where a viscus (viscera) is perforated or faecal contamination occurs
Examples - excision or draining of an abscess, bullae osteotomy for otitis media, perforated intestinal tract
6 host factors that can impact infections
- Age
- physical condition
- nutritional status
- diagnostic procedures - e.g. catheter
- concurrent metabolic disorders e.g. HAC
- Current medications e.g. corticosteroids, chemotherapy
what 3 things impact successful outcomes with no infections
Patient prep
Surgeon prep
Theatre behaviour
In what 5 surgical situations would you use antibiotics
Surgery >90 mins
Contaminated or dirty wound classification
Prosthesis implantation
Patients with pre-existing prosthesis undergoing certain procedures
Severly infected or traumatised wounds
Name 3 antibiotics that could be used during small animal surgery, and name which type of bacteria they are good against
Cefuroxime - 2nd gen. ceflosporin, broad-spectrum, good for gram +ve
Amoxicillin/clavulanate - broad spectrum, good for gram +ve, okay for anaerobic
Metronidazole - good for anaerobic e.g. large intestine surgery
Name 3 antibiotics which could be used in equine surgery
Procaine penicillin - IV
Gentamicin - IV
Oxytetracycline - NOT IV
Characteristics of an ideal suture
Easy to tie a secure knot
High tensile strength
Inhibit tissue actions
Non-toxic
Easily sterilised
Inexpensive
What are the 3 potential origins of suture material
Natural
Synthetic
Metal
2 behaviours of suture material
Absorbable
Non-absorbable
Advantages and disadvantages of absorbable suture material
Adv - They disappear, low risk of long term foreign body reactions
Dis - Lose strength over time, limited period of wound support
Advantages and disadvantages of non-absorbable suture material
Adv - Permanent, provide indefinable wound support
Dis - don’t disappear, possibility of delayed reactions
Advantages and disadvantages of braided suture material
Adv - easy to handle, very secure knots
Dis - Greater friction and tissue drag, more tissue trauma
Advantages and disadvantages of monofilament suture material
Adv - minimal tissue trauma, no capillary action
Dis - Harder to handle and knot, require different knots for security
Advantages and disadvantages of natural suture material
Adv - easy to handle and knot, high histocompatibility
Dis - moderate/high tissue reaction, low tensile strength
Advantages and disadvantages of synthetic suture material
Adv - high tensile strength, predictable biological behaviour
Dis - poorer knotting than natural materials
2 types of needle fixation, give an advantage and disadvantage of both
Eyed needle - multiple uses, increased tissue trauma
Swaged needle - minimal trauma, single-use
3 parts of the needle
Point
Body
Eye/swage
3 materials surgical instruments can be made from
- Stainless steel
- Chromium-plated carbon steel
- Titanium
What are scalpels used for and what handles and blades are used
Cutting skin
Number 3 handle most common
Number 4 handle - large animal
10 blade - commonly used for cutting
11 blade - stab incisions
15 blade - more delicate cutting edge
what are the 4 types of surgical scissors and what they are used for
- mayo scissors - cutting tough tissue
- metzenbaum scissors - delicate subcutaneous tissue and viscera
- suture scissors - cutting sutures
- iris scissors - 2 sharp tips - fine cuts
What are the 3 types of needle holders, and what is the difference
- Olsen Hager - have scissor blade built in
- Mayo Hager - no scissor blade
- Gillies - have scissor blade but no ratchet
What are the 4 types of tissue handling or thumb forceps and what is the difference (not ringed forceps)
- Treves rat toothed forceps - single tooth, larger
- Dressing forceps - no rat teeth
- Adson rat tooth forceps - small rat tooth
- Debakey forceps - longitudinal and transerve serrations - least traumatic
Name 3 types of haemostat forceps
- Halsted mosquito
- Spencer Wells
- Carmalt
Name 3 types of tissue/holding forceps and the differences (ringed instruments)
- Allis - quite traumatic, not applied to the skin
- Babcock - triangular shape, less traumatic
- Doyen - atraumatic, designed fr bowel
Name 4 types of self retaining retractors and the differences
- Balfour retractor - abdominal, 3 point
- Finchietto retractor - abdominal, 2 point
- Gelpi retractor - most commonly used, placed in pairs
- Travers retractor - less prone to twisting, can’t be used in small areas
Name 4 types of handheld retractors
- Senn
- Lagenbeck
- Hohman
- Malleable
Name 2 types of towel clamps
- Backhaus towel clamp
- Cross over towel clamp
What are the 4 stages of wound healing
- Haemostasis and inflammation
- Proliferation
- Maturation
- Wound contraction
What are they key features of the haemostasis stage of wound healing
Tissue damage => blood leaking from vessels
Activation of closing cascade
Platelet aggregation and release of cytokines
Cytokines trigger clotting cascade further and inflammatory phase
Stabilisation of platelet plug by fibrin formation
What are they key features of the inflammatory stage of wound healing
Vasodilation following transient vasoconstriction
cytokines in the fibrin clot attract WBCs (neutrophils and macrophages)
Destruction of cells by phagocytosis removes bacteria and devitalised tissue
What are they key features of the proliferation stage of wound healing
Formation of granulation tissue (macrophages, fibroblasts, new blood vessels)
Fibroblasts proliferate => extracellular matrix, elastin and collagen
Formation of new epithelial tissue
Wound deficit reduced
Contact inhibition - smooth layer of epithelium
What are they key features of the maturation stage of wound healing
Type III collagen => type I collagen
Cross-linking of collagen
Takes weeks to months
What 3 ‘patient factors’ affect wound healing
Age
Comorbidities
Nutrition status
What 2 ‘wound factors’ affect wound healing
Infection
Location
What concurrent treatments can affect wound healing
Corticosteroids
Radiation therapy
Name the 5 classifications of wound types
- abrasion
- avulsion
- incision
- laceration
- puncture
Key features of an abrasion wound
Loss of epidermis and some dermis
“Graze wound”
Key features of an avulsion wound
Tearing of tissues from their attachments
If on the distal limb - called degloving
No loss of skin - just torn away
Key features of an incision wound
Created by a sharp object - classical surgical wound
Minimal trauma
Key features of a laceration wound
Tearing causing an irregular defect
Key features of a puncture wound
Penetrating
Deep damage may be substantial
5 things to consider when assessing a wound
- type of wound
- wound age
- level of contamination
- lavage and debridement
- management
5 factors that influence bacterial contamination of a wound
- Vascular supply
- Devitalised tissue
- Foreign body
- Type of contamination e.g. bite wound vs cut by glass
- Type of bacteria present
3 main goals of wound management
- Promote healing
- convert contaminated => clean
- control infection
5 ways to debride a wound
- Surgical
- mechanical
- autolytic
- biological - rare
- enzymatic - rare
Describe 3 methods of mechanical debridement
- Lavage debridement - high volumes of lactated ringers solution or saline
- wet to dry dressings
- topical negative pressure wound therapy
describe key principals of autolytic debridement
Honey - osmotic effect - draws up fluid and also antimicrobial properties
2 things bandages provide
- stabilisation of wound surface
- protection from trauma and contamination
What 3 layers should all bandages have
- primary layer = in contact layer
- secondary layer = supportive or padded and applied light pressure
- tertiary layer = holds others in place, should stick to itself NOT the patient
Name 7 categories of primary layers for bandages
- Dry
- impregnated
- semi-occlusive
- absorbent
- alginates
- others e.g. honey, silver, iodine
- topical wound gels
Name 3 types of immobilising bandages/splints
- Robert Jones’s bandage
- Gutter splints
- Fibreglass impregnated with resin/ plaster of Paris cast
Name 4 common complications associated with incorrectly applied bandages/poorly cared for bandages
- Swelling
- tissue necrosis
- decubitus ulcers (pressure ulcers)
- patient interference
What 3 types of bandage are common in equine practice
- Simple bandage
- Figure of 8 bandage
- Robert Jones
What 2 situations do you splint in equine practice
- unstable fractures
- unstable tendon injuries
What are the main elements of Halstead’s principals of good surgical practice (x7)
Gentle tissue handling
Strict asepsis
Haemostasis
Preservation of blood supply
No tension on tissues
Good approximation of tissues
Obliteration of dead space
What 5 regions is the abdominal cavity divided into for a exploratory laparotomy
- Cranial abdomen
- GIT
- Right paravertebral region
- Left paravertebral region
- Caudal abdomen
What are the 3 main stages of bone healing
Inflammatory
Restorative
Remodelling
Describe key features of inflammatory phase of bone healing
Lysis of osteocytes => attract inflammatory cells and macrophages
Blood clot forms at the fracture site
Describe key features of restorative phase of bone healing
Soft callus formation
External and internal calluses are formed
New blood vessels
Newly formed cartilages are substituted by bone tissue (endochondral ossification)
Produces a hard callus
Describe key features of remodelling phase of bone healing
Hard callus replaced by regular bone
Ends of bone are enveloped by a fusiform mass
Remodelling occurs - osteoclasts
What 2 types of healing can occur in the restorative phase of bone healing
First intention healing - minimal callus formation
Second intention healing - natural healing
Describe process of healing by first intention (bone)
Direct formation of bone tissue without creation of bone callus
What 6 conditions must occur to allow healing by first intention (bone)
Immediate stabilisation
Good blood supply
Perfect reduction of fracture edges
Absence of micro-movements at the level of the fracture line
Interfragmentary compression
Absence of infection
Describe second intention healing (bone)
Where a bony callus forms
Produced due to late treatment, poor blood supply, infection, no compression forces
What is an articular fracture
Where a bone breaks to the joint (articular surface of the bone)
What is a closed vs open fracture
Open fracture = when skin is broken with the fracture
Closed = bone is broken but skin is intact
What is an avulsion fracture
When a small chunk of bone is torn away by a tendon or ligament
What ‘patient factors’ affect fracture scores
Weight
Age
Ability to manage cage rest
Concurrent illness
What about the fracture itself can affect the fracture score
Type of fracture
Open or closed
Associated soft tissue injuries
Single or multiple fractures
Non patient factors affecting fracture score
Owner finances
Owner commitment
Surgical expertise of vet surgeon
Surgical equipment available
What 4 forces can be applied to a fracture
Bending
Torsion
Tension
Axial compression
On the following long jones, which aspect is the tension aspect? (femur, tibia, radius, humerus, mandible)
Femur - lateral aspect
Tibia - medial aspect
Radius - cranio-medial aspect
Humerus - latero-cranial aspect
Mandible - dorsal aspect
Why is it important to know which is the tension aspect of the bone when applying a plate
Plate is always applied to the tension side of the bone
Will not be broken by tensile force but will be broken by successive compressions
What is the formula for strain in terms of fractures
Strain = change in length/original length
Name 5 main options for fixing a fracture
Intramedullary pin and cerclage wire
Plating +/- compression
Intramedullary nail
External fixator
Pin and tension band
Which forces are intramedullary pins good and bad at counteracting
Good - bending forces
Bad - Axial compression, rotation
What are the 2 placement options for an IM pin
Normograde placement (from the proximal end)
Retrograde placement (enters proximal fragment distally)
Why are external fixators really useful in fracture repair
Counteract all forces applied to a fracture
Good for open fractures where wound management may be required
Name some complications associated with external fixators
Pins are prone to infection
Require frequent examinations
May require staging down
Several follow up radiographs often required
What are the benefits of plate fixation of fractures
Allow reconstruction of comminuted fractures
Protect against axial rotations
What force do plate fixators NOT protect against in fractures
Bending
Name 3 types of plates for fixing fractures
- Buttress plate
- Neutralisation plate
- Compression plate
Explain how lag screws work and why it is used
Allow compression to be applied to a fracture
Glide hole and thread hole pulls far fragment of bone against the near fragment
Things to consider with avian fractures
Pneumatised bone
Periosteal blood supply of pneumatised bone must be preserved
Avian bone heals mostly from the endosteum
In what 4 fracture situations do you immediately euthanise a horse
- Comminuted fractures of proximal and middle phalanx
- Compound/open fracture of long bone
- Complete fracture of long bones
- Pelvic fracture
What suture material, size, pattern and other techniques do you use to close a gastrotomy
Material - absorbable monofilament
Size - 3/0 in cats, 3/0 or 2/0 in dogs
Pattern - 1 layer closure of 2 layer closure (more common)
Omentalise
Why do we “omentalise” when performing intestinal surgery
Draping omentum over site of incision
Improves vascular supply
Lymphatic drainage
Rich source of inflammatory and immunogenic cells
Name 4 reasons for performing a urinary bladder cystotomy
- Calculi need removing
- Biopsy
- Tumour
- Ureteral ectopia
During which period are the intestine/bladder most likely to breakdown after surgery
72-96 hours (lag phase)
This is when all support ad strength is provided by the sutures
Name 3 complications which could occur after abdominal surgery
Wound infection
Peritonitis
Uroabdomen
Clinical signs of postoperative complications abdominal surgery/bladder surgery
Dull, lethargy, anorexic
Bladder breakdown => vomiting, diarrhoea
Abdominal guarding
Pyrexia, increased HR and RR
Which layer of the lines alba is most important when it comes to closure
External rectus sheath
Gives examples of prophylactic surgery for tumours
Ovariectomy/ovariohysterectomy for mammary neoplasia
Give an example of an oncological emergency requiring surgery
Bleeding splenic hemangiosarcoma
What is ‘staging’ of a tumour and what imaging modality is best
looking for metastatic spread - CT scan best
Name the 4 types of tumour removal surgeries (margins)
- debulking/cytoreduction - leaving some behind
- marginal resection
- wide resection
- radical resection
Name 2 types of clinical reasoning
- pattern recognition
- problem based clinical reasoning
what are the 4 questions/stages to work through during problem based clinical reasoning (type 2)
- what is the problem
- which body system is involved and how
- where in the body system ins the problem located
- what is the lesion
What are the benefits of shared decision making
Tailors decisions to individual client
informed consent
Better adherence to treatment plan
Strengthens the relationship between vet and client
Less likely to get complaints
What are the disadvantages of shared decision making
More time consuming?
