Surgery, preparation, protocols and good theatre practice Flashcards
Asepsis?
The absence of pathogenic microbes or infection in living tissue.
Antisepsis?
The use of antimicrobial chemicals on living tissue
Disinfection?
Destruction of pathogenic microbes e.g. use of germicidal products on inanimate objects.
Sterilization?
Destruction of all microorganisms.
Are surgical wounds sterile?
No - all become contaminated with bacteria, but not all contamination becomes infection.
What 3 areas of preparation can increase successful outcome?
- Patient prep
- Surgeon prep
- Theatre behaviour
Where should patient prep be performed?
In a separate room to the theatre.
What is the issue with hair removal?
Hair is a gross contaminant and significant reservoir for microbes and organic debris.
By how much does hair removal increase the chance of contamination prior to anaesthesia?
3x higher chance.
Why should razors not be used?
Grazes and associated with a 10x increase in contamination risk.
How should you treat open wounds?
First flush them and then cover with sterile gel.
What are the pros and cons of depilatories?
Pros: Atruamatic, good for rabbits
Cons: Expensive, cause a lot of mess, not good on coarse hair and cause frequent skin reactions in cats.
What is the best method of hair removal?
Clipping - lower rate of surgical infection
When should you NOT clip the wound and why not?
The day before, increases the bacterial load.
How far should you clip around the proposed surgical site?
10-15cm
How do you then remove the hair?
vacuum the table and the patient.
How much of the limb would you clip for orthropaedic surgeries?
The entire limb.
What should you do with the paw during orthopaedic surgery and why?
The paw harbours a lot of bacteria and is difficult to deal with nail beds and pads therefore should be covered with impermeable material e.g. surgical glove.
What are the three aims of skin preparation?
- reduce the level of gross dirt and transient microbes.
- Rapidly reduce resident microbe levels to sub-pathogenic levels with minimal tissue irritation.
- prevent rapid re-bound growth of microbes.
is skin sterile and it not, why not?
Skin is not made sterile because antiseptic does not reach the lower levels of the skin - 20% bacteria there.
What are the three stages to skin preparation?
- initial removal of gross dirt and transient microbes
- surgical scrub with detergent-based solutions
- alcohol aqueous solution rinse.
What should be worn during surgical site preparation?
Gloves
What should and should not be used to clear the area?
Should use good quality swabs. should not use cotton wool (leaves fluff) and should not use scrub brushes.
How do we avoid hypothermia in our patients?
use warm water and avoid wetting excessively.
Why should we not be rough when preparing the patient?
trauma and increased bacterial release from the hair follicles.
What is very important when prepping the patient?
Start in the middle, work out and discard swab. CONTACT TIME is very important!
What should the final stage of prep be when in the theatre?
No touch with alcohol tincture.
What happens if there is any contamination?
need to start the protocol again - do not clip in theatre!
How should we prepare the foot?
Secure in a glove and swill the foot in there.
Name 7 features which make for an ideal antiseptic?
- rapid action
- persistent effect
- residual action
- active in organic matter
- non-toxic and non-irritant
- easy to use, cost effective and economic
- Bactericidal - broad spectrum activity
How does povoidone Iodine work?
It damages the cell wall and inhibits protein synthesis
What is iodophor?
It is iodine complexed with high MW carrier to reduce toxicity and staining.
What happens as you increase the dilution of iodophor?
It increases in bactericidal activity (10% povidone-iodine diluted to 0.1% solution has the most bactericidal activity).
Name 4 benefits of using 10% povoidone-iodine?
- rapid action
- bactericidal - broad spectrum
- kills fungi, most viruses, protozoa, yeasts and micobacteria
- sporicidal if kept in contact for long enough (15 mins-2hrs)
How long is povoidone iodine effective for?
1 hour (some can last 4-6 hours)
What decreases the activity of povoidone iodine?
The presence of organic material
What is a contraindication of using povoidone iodine?
50% chance of skin reaction e.g. acute contact dermatitis, sensitivity in people.
What is the toxicity of povoidone iodine?
Toxic if used on open wounds, mucus membranes and peritoneal surfaces.
What is hibiscrub?
Chlorhexidine gluconate
What chemically is hibiscrub?
Bisbiguanide compound
How does chlorhexidine gluconate work?
It alters the cell wall permeability and causes protein precipitation
What spectrum is hibiscrub?
Broad spectrum (better for against gram +ves than gram -ves)
Which resistant bacteria is hibiscrub resistant against?
MRSA
What else is hibiscrub effective agaiinst?
Effective against most yeasts, fungi and some viruses
What is hibiscrub ineffective against?
Spores and mycobacteria.
Is hibiscrub active in the presence of organic matter?
YES
What is the residual and persistent activity of hibiscrub?
Excellent - binds to stratum corneum therefore repeated application has a cummulative effect.
Are skin reactions common? If there are any, what are they?
Skin reactions uncommon.
With prolonged use, might get photosensitivity, contact dermatitis and hypersensitivity.
Why is hibiscrub okay for neonates?
Because there is minimal skin absorption.
What needs to be avoided when using hibiscrub?
- ototoxic - middle ear and inner ear –>deafness
- Neurotoxic –> avoid brain and meninges
- concentrations above 0.05%, toxic to conjunctiva and cornea
What would you therefore use during eye or eye surgery?
Dilute iodine.
What are alcoholic tinctures used for?
The second step after povoidone and chlorhexidine use
What is the activity of alcoholic tinctures?
Broad spectrum - bactericidal
What does alcohol kill?
Good against bacteria and fungi, some viruses, poor against spores.
When is max kill achieved using alcoholic tinctures?
At least 2 minute contact: 60-70%
When is the efficacy of alcoholic tinctures depressed?
In the presence of organic matter.
Name the 5 contra-indications of using alcohol tinctures?
- relatively non-toxic, unless used in newborns
- Can cause hypothermia if evaporated greatly
- avoid open wounds
- skin drying
- flammable and explosive
What has the highest and most rapid kill rate?
Alcohol
Name 4 reasons chlorhexidine is superior to povoidone iodine?
- broader spectrum of antimicrobial activity
- longer persistent and residual activity
- minimal loss of activity in organic matter
- fewer skin reactions and toxicity.
What is the most important thing to remember when using ANY preparation agent?
Allow sufficient contact time.
What should you use for eyes and ears and at what concentration?
Povoidone iodine
1: 10 dilution for eyelids
1: 50 dilution for occular surfaces and conjunctival sac
How do you remove the residual solution from the eyes?
With saline or hartmanns.
What should you never use near the eyes?
NEVER use products containing detergents of soaps
What dilution should you use in the ear canal?
1:10
Should alcohol be used in the ear canal?
No - only use alcohol on the pinna
Why should we not use chlorhexidine gluconate in the ears?
Ototoxic - neurosensory deafness.
Which preparation is okay to use on open wounds?
Hibiscrub (0.05%) - 2-4% for scrub
How should you treat the wound following preparation?
pack wound with sterile KY jelly.
How should you lavage open wounds?
With warm, sterile Hartmann’s or saline
What should you do with the wound whilst the rest of the area is prepared?
pack with moist swabs
What are the non-sterile barriers of surgeons?
Mask, shoes, hats, scrubs
What are the surgical barriers?
Gloves, gowns.
What is a primary source of operating room contamination?
Shedding
How do scrubs help with this?
Scrubs reduce the amount of shedding of skin debris.
When should you NOT wear scrubs?
When outside of theatre, examining cases, changing bandages, visiting wards etc.
Why are hats worn?
To stop hair shedding which is a major source of bacterial contamination.
What do masks protect from?
Saliva and microorganisms
What is the small particle filtration of masks?
90%
How long are masks effective for?
8 hours.
Why should mask not be worn untied and dangling?
increased scrub suit contamination
Why don’t we want to be too rough when scrubbing?
We do not want to damage skin as this would lead to increased bacteria.
How long should all surfaces be exposed to scrub in the scrub protocol?
At least 2 minutes.
Where should your hands be during the scrub protocol?
Above the elbows.
What is sterilium?
85% ethyl alcohol
how effective is sterilium?
kills 99.9% bacteria within 15 seconds
What does sterilium kill?
Yeasts, bacteria, viruses, TB and mycobacteria (includes HIV)
Which has a more lasting effect? Surgical hand rub or surgical hand scrubbing?
Surgical hand rub (sterilium)
Name 4 advantages to using sterilium?
cost and time saving
non-irritating/ moisturising
What must not be present so that sterilium works?
must have no organic debris present e.g. wash hands and nails.
How long do you need to apply sterilium for?
1.5 minutes (as effective as 3 mins)
Which is more effective generally? Surgical hand rub or surgical hand scrub?
Surgical hand rub - lasts longer and faster action
How do you towel dry?
Consider the towel in quarters. Use the top two quadrants for the hands and the bottom two quadrants for the arms.
Name two of the most common mistakes of contamination?
Going back to dry hands with towel.
Towel touches the front of the scrubs.
What are the two types of gowns and drapes?
Re-usable woven fabric and disposable non-woven fabric.
name 4 downfalls of using woven, reusable fabric?
- ineffective when wet
- 30-50% culture +ve after surgery
- Bacterial penetration at seams - need inspection after laundry
- Lint production (textile fibres)
Name an advantage of woven, reusable fabrics?
They have a very tight weave - more effective barrier
What can disposable fabrics be made out of?
polyester, wood pulp and synthetic polymers.
What are 3 advantages of non-woven materials?
Random orientation of fibres means inpenetrable to fluids and bacteria.
They have lower particle counts
they have lower +ve results following surgery
What is a downfall of using non-woven fabrics?
They are more expensive.
Are gloves an absolute barrier?
No - 1.5% might have holes and by end of surgery, 12-31% might have holes.
What should you do as soon as you notice a hole in the gloves?
ALWAYS change gloves as soon as noticed.
What does closed gloving mean?
Keep hands and fingers within the cuff of the gown sleeves. No contact with the external surfaces.
Which gloving technique is better to use?
Closed - open is best avoided.
What are the three types of drapes?
Cotton muslin +/- skin towels
Disposable
Adhesive incise drapes
What are the pros and cons of adhesive incise drapes?
They are expensive.
They do not stick well and no strong evidence of reduced infection rates.
They are however waterproof.
What draping technique is standard?
quarter draping
What should you NEVER use to attach drapes?
Tissue forceps.
What are the three things in the surgical sterile field?
The surgical site + surgeon + instrument trolley
What are the parameters of sterility of the surgeon?
Chest to level of sterile field
Cuffs to 5cm above elbow.
What is not sterile in terms of the table and the surgical trolley?
Nothing below the table and nothing below the instrumental trolley.
Can the patient be made sterile?
No, but everything is aimed at reducing the contaminants.
What should you NOT do if you are not sterile?
You should not lean over the sterile field.
