VNSA10 Flashcards
What is the aim of an operating theatre?
To provide an area that is free from infectious organisms
What are potential sources of infection ?
Equipment
Animal
People
Surgical site
What protocols should be in place to reduce risk of infection in theatre ?
Correct theatre attire
Min num of people and movement
New set of instruments for each op
Surgical list in order clean to dirty
A room for dirty procedures
Sterilisation programme
Ambient temp and good ventilation
Sterilisation programme
Site prep before entering theatre
Rectifying breaks in sterilisation
Discarding contaminated instruments or equip
Record of surgeries and instruments for tracking
Strict cleaning protocols
SOPs
Name operating theatre design principles
Being an end room
Sufficient size allowing ease of movement and sterile trolleys
Easily cleanable (PCV walls, curved floors etc)
One way movement of personnel
Clear separation between clean and contaminated areas
Theatres designated for specific surgery (orthopaedic, general and dirty)
What can the patient prep area be used for?
Induce anaesthesia
Prep of surgical site
Placement of IV catheter
Catheterisation of bladder
What should the average temp of the operating theatre be?
15-20 degrees
Important as anaesthetised patients cant control body temperature
Define sepsis
Combination of infection and systemic inflammation
Define asepsis
Where no living disease causing microorganisms are present
Define antisepsis
Process of preventing the growth of infectious germs like bacteria, virus and fungi
Define endogenous
Produced or synthesised within the organism or system
Define exogenous
Describes substances originating from outside the organism
Define elective surgery
Surgery isn’t emergency and can be scheduled in advance
Define necessary/urgent surgery
Needed soon but can be delayed
Define emergency surgery
Needed ASAP, life threatening
Define clean surgery
Surgical wound made under aseptic conditions
Does not enter any contaminated viscus and there is no break in sterile technique
Eg - neutering, uncomplicated hernias
Define clean-contaminated surgery
Surgical wound made under aseptic conditions that enters the oropharynx, respiratory, alimentary or urogenital tracts, but no other source of contamination.
Eg - lung lobectomy, gastrostomy, tracheotomy
Define contaminated surgery
Major spill of contaminated material at surgery, or break in sterile technique, or entry into a viscus with a high bacterial load.
Eg- abdominal surgery where gut contents are spilled, oral surgery, wound over 4hrs old, lower bowel surgery.
Define infected surgery
Surgical site is known to be already infected
Eg - aural surgery, abscesses, old wounds, removal of necrotic tissue
What are the essentials for an operating theatre?
Adequate lighting (fixed and adjustable)
Theatre trolley
Anaesthetic machine
Scavenging
Seamless
Wall mounted clock
Positive pressure air ventilation
Crash box
Table
What equipment and design should be in the prep area?
Adjustable height table
Anaesthetic machine and selection of ET tubes and circuits
Seamless
Weighing scales
Bins (clinical, sharps, normal)
Clippers and blades
Skin prep solutions
Bandages and dressings
Restraint equip
Dental equipment
What equipment and properties should the scrub room have
Stainless steel sinks
Seamless
Elbow, knee or foot operated taps
Scrub solutions
Sterile gowns, gloves, caps and mask away from splash zone
What equipment and properties should the sterile store have?
Sterile packs of instruments and supplies in date order
Enclosed cabinet for storage
Seamless
Control of humidity/temp/handling
Disposable sterile items
What equipment and properties should the sterilisation room have?
Autoclave or appropriate sterilisation equipment
Seamless
Sterilisation pouches, nylon film, metal drums, boxes or cartons
Sterilisation indicators
Sinks for washing used equipment
What equipment and properties should the recovery area have?
Recovery cages, tanks etc
Viewing window
Seamless
Monitoring equipment
Crash trolley and emergency box
Oxygen
IV fluids and infusion equipment
Bedding
External heat sources (heat pads, water bottles, warm air blankets etc)
How long can a tourniquet be used to limit blood loss in surgery?
15-20 mins
Name the 3 suction tips and their function?
Frazier - used for fine delicate suction which may be controlled by covering the hole at the base of tip
Yankauer - has a bulb at the end which reduces trauma and allows maximum visibility. Open tip allows rapid aspiration.
Poole - specially designed to remove pooled blood, fluids and debris. Allows for pinpoint suctioning - useful in abdominal surgery.
What is cryosurgery and when can it be used?
Liquid nitrogen used to destroy living tissue by controlled application of extreme cold. Aim is to kill cells in a diseased target whilst producing minimal damage to normal surrounding tissue.
Used in - cancer, skin growths, removal of tumours or lesions, lumps/masses
Cryosurgery precautions
Liquid nitrogen = harmful substance - subject to COSHH regulations and SOPs
Only can be transported in an insulated supplied supplier metal container
Insulated gloves and full PPE when handling
Use a metal funnel when filling
Patient prep = skin clipped and basic prep and insulate surrounding skin
Skin will be erythematous and oedematous when finished
Wash and disinfect then autoclave if possible probe when thawed.
Define PAT testing
Portable appliance testing
What is the composition of surgical instruments?
Stainless steel
A ferrous alloy with a minimum of 10.5% chromium content.
Doesn’t stain, corrode or rust as easily as normal steel.
Nickel and chromium added to make it stainless.
What are some parameters of stainless steel
High resistance to corrosion
Great strength
Attractive surface finish
Chromium improves steel quality
The more chromium in the alloy the more resistant it is to corrosion
What variety of stainless steel is also known as “cutlery stainless steel”
Martensitic
May be a touch magnetic
Most commonly used in instruments
Greater hardness through heat treatment
Corrosion resistant
Provides strength and durability
Eg - biomedical cutting instruments, scissors, bone cutters and chisels
What variety of stainless steel is also known as marine grade stainless steel?
Austenitic
Immune system reaction to nickel is a potential complication
Hardened by being worked
High resistance to corrosion
Not as hard as martensitic
Eg - implants and equipment thats put under pressure, bone fixation screws and plates, body piercings, trolleys
Tungsten carbide
One of the hardest materials known (aka ‘man-made diamond’)
Hardness makes it resistant to corrosion and wear
It’s sintered at 1458°c to 3200°c
These inserts are added to instruments to enhance their performance and longevity
Inserts are micro bonded to the working end of the device
Expensive
Avoid them coming into contact with benzyl ammonium chloride
Chromium plated stainless steel
Popular as low price
Rust, pit and blister due to plated surface being susceptible to low pH solutions
Blunt quickly
Easy to maintain
Highly polished surface
Titanium
Light, strong and lustrous white metal
Alloyed with 6% aluminium and 4% vanadium
Corrosion resistant inc oxidising and chloride environments
Can be heated to 440°c
Resistant to fatigue
Often selected for metal plates or femoral stem implants
Ophthalmic instruments as less glare - inc visability
Expensive
Vitallium
More resistant to corrosion than stainless steel
Expensive to manufacture
Screws made of this bond securely to bone - care if removing to not break head off
Mostly used in dentistry
Can you use different materials with implants
NO
Stainless steel plates shouldn’t be held with vitallium screws due to electrolytic and chemical reactions
Corrosion of metal implants resulting in local tissue reaction leading to wound breakdown or non-union of the fracture.
Care with instruments used also
Name the 3 types of finishes on surgical instruments
Mirror - highly polished, doesn’t discolour easily
Satin - dull matt (low glare) has been sandblasted. Easier to stain.
Ebony - black, used for laser surgery
How should instruments be stored
Separate area
Dust free, dry and well ventilated
Ideally in closed cupboards
Handled as little as possible to minimise damage
Packed loosely on shelves
Sharp points covered
Unused packs to be repacked/re-sterilised after 12 weeks, 6mths if double bagged or up to expiration
How to lubricate instruments
Lubricants recommended by manufacturer
Avoid mineral oils and grease as they leave a film on the surface
Antimicrobial water-soluble lubricants (instrument milk)
No need to rinse
Identify ideal suture material features
-suitable for use in any situation
-readily available and inexpensive
-readily sterilised by steam or ethylene oxide
-show high initial tensile strength combined with small diameter material
-have a good knot security
-produce minimal tissue reaction - inert, non-allergenic, non-carcinogenic and non-electrolytic
-show good handling characteristics- easy to handle when wet or dry and pass through material without friction or cutting
-not create an environment for bacterial growth
-be absorbed after its function has been served
Define tensile strength
The breaking strength per unit area of tissue
Define knot security
Related to the surface frictional characteristics of the material - every suture is weakest where it’s tied.
Often the strongest sutures have the poorest knot security.
Define stiffness and elongation
The less force required to stretch a suture, the more it will elongate before it ruptures
Define tissue reaction
The response of the tissue to the suture material involved
Define memory
The tendency of the material to return to its original shape.
A material with a high memory tends to unlink during knot tying
Knot security = poor with materials possessing high memory.
Define chatter
The lack of smoothness as a throw of a knot is tightened down
Define tissue drag
The degree of frictional force developed as the material is pulled through the tissue
Define capillarity
The extent of which tissue fluid is attracted along the suture material.
Materials with a high capillarity act as a wick and encourage fluids to move along them. Such materials should not be used in the presence of sepsis.
Absorbable suture material
-ideally will absorb as soon as the tissue is able to support itself, this will vary to tissue type
-suture will be absorbed in 2 stages: loss of strength and loss of mass
-Most concerned with loss of strength
-no foreign material should be left in the patient which could cause a tissue reaction later
-natural absorbables are broken down by phagocytosis (some degree of tissue reaction)
-synthetic absorbables are broken down by hydrolysis (minimal tissue reaction)
-lose tensile strength by 60 days.
Non-absorbable suture material
-suture material remains in the body for an indefinite length of time. It can migrate through the body tissues over time or cause a foreign body reaction.
-often used in the skin
-support tissue longer than an absorbable suture (longer than 60 days)
-material is neither hydrolysed or phagocytosed (instead becomes encapsulated within fibrous tissue)
-used when prolonged mechanical support is required.
Synthetic suture material
Man-made material
Very predictable
Stronger than natural
Causes minimal tissue reaction later
Natural suture material
Tend to cause more severe tissue reactions than synthetic and huge tissue reactions when placed internally
Knot well
Easy to handle
Variable in strength
Less predictable than man-made materials
Monofilament tissue reactions
Less likely to cause infection but they’re usually stiff making them difficult to work with and reduces knot security.
Single strand material
Smooth to the touch and to pass through tissues
Knot tying can be difficult as material can slip
(Eg catgut)
Multifilament suture material
Made up of multiple strands braided together - makes them less stiff and improves knot security on the downside rigid surfaces encourage capillarity - Often coated with wax, Teflon or silicon for this reason. This doesn’t weaken knot security
Easy to handle
Knot well
Secure
May cut through tissues
Rigid enough capillarity
When placed in infected tissue the infection may become persistent.
Uses of suture materials
(Types of suture material in different tissues)
Skin = monofilament nylon or polypropylene, metal staples. Avoid materials with capillarity action.
Subcutis = fine synthetic absorbable material with minimal tissue reaction (polydioxanone, polyglot in, polyglycolic acid)
Muscle = synthetic absorbable, non-absorbable (nylon)
Fascia = synthetic non-absorbable if prolonged suture strength is required.
Hollow viscous = synthetic absorbable or polypropylene. In bladder use monofilament synthetic
Tendon = nylon, polypropylene, stainless steel
Blood vessels = polypropylene: least thrombogenic is silk
Eyes = synthetic absorbable (eg - polyglactin, polydioxanone)
Nerves = nylon or polypropylene as minimal tissue reaction
Alternative methods of skin closure
Allow rapid wound closure, reduce op times, good wound healing results, minimal scarring, cost effective and they bind wound hedges together so natural healing occurs
Eg: stapes, tissue glue, adhesive tape, staplers, suture and skin staple removal kits, tissue adhesive
How are surgical needles made ?
Corrosion-resistant stainless steel.
Sharp and designed to penetrate tissue with minimal resistance
Rigid but allow for some flexibility
Swaged needles
Already have suture material attached.
A: needle in perfect condition, tissue trauma minimised
D: cost, fresh needle used for every procedure
Uses: bladder, uterus, intestine, stomach, vessels of any sort and solid organs
Eyes needles
Require threading
A: economic use of suture material, specialised needles
D: tissue trauma due to eye size, loss of needle tip sharpness, bending and corrosion due to repeated use.
How are needles classified?
Shape, size, shape of body, type of cutting point, thickness of needle.
Shape of length: straight, 1/2 curved, 3/8 circle, 1/2 circle, 5/8 circle
Round bodied needle
Taper-point
Designed to slide through body tissues, dilates rather than cutting them.
As the needle passes through the tissue a leak proof suture line is maintained.
Used where tissues will easily split: viscera, subcuticular tissues and friable tissue
Cutting needle
The body is triangular with the apex of the triangle to the inside of the needle.
Very sharp, cuts rather than dilate; creates weakness allowing suture tear out.
Used for cutting through skin and tough tissue
Taper-cutting needle
Cutting tip and round body
Increasing tissue penetration without increased tissue trauma
Ideal for tough or calcified tissues: cardiac and vascular procedures
Reverse cutting needle
The body is triangular with the apex of the triangle to the outside of the needle.
Very sharp, cuts rather than dilates, ideal for skin.
Have their cutting surfaces on the convex surface and are ideal for tough tissue like skin, tendon sheath, oral mucosa and useful in subcuticular skin closures.
Have more strength then conventional cutting needles and there is reduced risk of cutting through tissue.
Commonly used in ophthalmic and cosmetic surgery where minimal trauma is paramount.
Spatulated needle
Body is flattened on the inside and outside to enable the needle to penetrate between 2 layers.
Used in intra ocular surgery.
Micropoint needle
Very fine needles with a sharp cutting edge
Used in ophthalmic surgery and microsurgery
What is an apposing suture pattern?
Sutures bring the tissues in direct apposition
What is an everting suture pattern?
Sutures turn wound edges outwards
What is an inverting suture pattern?
Sutures turn tissue inwards
What is an interrupted suture pattern?
Maintains strength and apposition
Takes time and much suture material attached
Maintains strength and apposition
Takes time and much suture material
What is a continuous suture pattern?
Ease of placement and less suture material used.
Knot slippage results in suture failure
