Asepsis & Antisepsis in Surgery

Dept of Surgery

National University of Singapore

Asepsis in Surgery

Asepsis : freedom from infection or prevention of contact with microorganisms

Aseptic technique : instruments, air, drapes, gloves and gowns are free from microorganisms

Antisepsis : prevention of sepsis by inhibition or destruction of agents

Asepsis

Defined as a process or procedure performed under conditions in which bacterial contamination has been minimised

1847 Semmelweis 1865 Lister

Asepsis

Technique wash hands and instruments with

carbolic acid wear gloves spray OT with carbolic acid

Lister - Lancet 1867 amputation mortality 46% 15%

Asepsis TodayOT

20 air changes per hour filtered air laminar flow if needed

Surgeon hand scrub iodophors or

hexachlorophene solution sterile gloves - technique sterile gown - technique aseptic technique in surgery

Asepsis today

Patient shave only day of op skin prep with iodophor or hexachlorophene drape with impermeable membrane protect wound beware long surgery, drains, other illness

Instruments - autoclave or gas sterilised

Antisepsis Bacterial flora

Resident: Coag –ve Staph, Corneybacterium,Acinetobacter, enterobacterium

Transient: Staph aureus, MRSA

Antisepsis- Destruction or removal of the transient flora

Surgical Site Infection (SSI) 10-15% of nosocomial infections

60% at the incision site

Significant morbidity and mortality

Increased hospital stay and costs

Superficial Incisional SSI Occurs within 30days and involves skin or

subcutaneous tissue and one of the following

Purulent discharge Positive culture Clinical signs of infection Clinical diagnosis

Deep incisional SSI Occurs within 30days if no implant left in situ Occurs within 1yr if implant left in situ and

one of the following

Purulent discharge from deep incision Dehisence of deep incision Discharging abscess Clinical diagnosis

Organ/Space SSI Occurs within 30days if no implant left in situ Occurs within 1yr if implant left in situ and one of the

following

Infection involves organ/ space or any related anatomy

Purulent discharge from deep space Positive culture Deep abscess confirmed clinically or radiologically Clinical diagnosis

Surgical wound classification Clean / Class I- Uninfected operative wound in

which no inflammation is encountered. Primary closure with closed drainage. Respiratory, alimentary and genito-urinary tracks are not involved. (1.5%)

Clean-contaminated/ Class II- Any operative wound in which the respiratory, alimentary or genito-urinary tracks are opened in a controlled manner without contamination. (8%)

Surgical wound classification Contaminated/ Class III- Open fresh accidental

wounds. Operations with major break in sterile techniques. Gross contamination or major spillage. Non purulent inflammation (10-15%).

Dirty-infected/ Class IV- Old traumatic wounds with devitalised tissue and those that involve existing clinical infection or perforated viscera. Organisms involved were present in the operative field before the operation (25%).

Patient factors Age Nutrition DM Obesity Smoking Colonisation Immunosuppression Blood transfusion Anaemia

Malignancy Co-existing infection Length of pre-operative

stay

Operative factors Category of operation Duration of operation Skin asepsis Surgical scrub Preoperative shaving Preoperative skin prep Antimicrobial

prophylaxis OT sterilisation Sterilisation

Foreign material Surgical drains Surgical technique Poor haemostasis Dead space obliteration Tissue trauma

Normal body flora Anatomical site

Head and neck

Thorax

Upper GI

Lower GI

Female genital tract

Flora Staph (aureus & coag neg), Strep,

cornybacteria, Neisseria, haemophilus, anaerobes

Staph (aureus & coag neg), As oropharyngeal and Gram neg

rods including enterobacter, Lactobacilli

AerobicGram neg rods including enterobacter, enterococci. Anaerobes- bacteroides, clostridium yeasts

Large bowel flora, Staph , Strep, corneybacteria and lactobacilli

Hand hygiene Procedure Patient

Risk of SSI= Dose of bacterial contamination X virulence/ resistance of patient

Hygienic hand wash: “ Post contamination procedure using a bactericidal wash that is active against transient organisms to prevent further transmission”

Asepsis in Surgery

Hygienic hand rub

Bactericidal agent which is alcohol based without the addition of water

Contains emollient

Fast acting and easy to use

Can be used repeatedly

Surgical scrub To remove debris and transient micro organisms

from nails, fingers and forearms

Reduce the resident flora to a minimum

Inhibit rapid rebound growth on bacterial flora

The anti microbial agent should reduce micro organisms on intact skin, be non irritant, broad spectrum, fast acting and have a residual effect.

Fingernails Sub ungal regions harbour bacteria

Trimmed nails

No varnish or artificial nails

Use a scrub

Patient preparation Length of stay proportional to SSI rate

MRSA colonisation

Shower with antiseptic agent

Shaving before procedure

1% Iodine or 0.5% Chlorhexidine in 70% alcohol

Care with diathermy

Drapes Aseptic barrier

Careful placement around surgical field

Cotton vs. disposable

Wet drapes provide ideal culture medium

Antiseptic agents Rapid action Broad spectrum Persistent effect Safety Acceptability

Alcohol, chlorhexidine, Triclosan, Iodine, Iodophores

Binds to stratum corneum

Antiseptic agents

Alcohol

Chlorhexidine

Triclosan

Iodine / Iodophores

Denaturation of protein

Disruption of cell wall

Disruption of cell wall

Oxidation/substitution of free iodine

Skin care

Avoid damaged / cracked skin

Latex allergy

Gloving

Emollients

A good scrub..

a) Thoroughly moisten hands and forearms

b) Sub ungal areas cleaned with nail cleaner

c) Apply antimicrobial agent with friction

d) Fingers and arms scrubbed on 4 sides

a) Hands higher than elbows

b) Avoid splashing

c) Discard brush

d) Repeat as necessary!

• Thoroughly moisten hands and forearms

• Sub ungal areas cleaned with nail cleaner

• Apply antimicrobial agent with friction

• Fingers and arms scrubbed on 4 sides

• Hands higher than elbows

• Avoid splashing

• Discard brush

• Repeat as necessary!

Decontamination

Decontamination- process of removing or destroying micro-organisms and organic matter. Making a re-usable item safe for patients and staff.

Cleaning- process that physically removes organic matter ( blood, tissue, body fluids) but does not remove micro-organisms.

Decontamination

Disinfection- process that reduces the number of micro-organisms to a level that is not harmful at the site of use. Kills or removes micro-organisms with the exception of bacterial spores.

Sterilisation- process which frees an object of all living organisms.

Methods of decontamination Disinfection

Physical- Low temp steam Boiling water Washer disinfections

Chemical Chemical disinfectants (Glutareldehdye 2%, Cidex, Miltons, Clearsol,

alcohol)

Methods of Sterilisation

Steam (autoclaving) Hot air (ovens) Ethylene Oxide Low temp steam and formaldehyde Gas plasma Irradiation Sporicidal chemicals

Drains

Drains

Apparatus used to remove debris after surgery

Early drains were gauze or rubber

Modern drains - plastic, siliconised, soft rubber

Drains

Types of drains

Open drains

Closed drains suction or free sump drains

Drains

Open drains External end left free Collection into bag or gauze Closed drains External end into collection

device Suction may be applied

Drains

Open drains soft and atraumatic open system - bacteria skin in contact difficult to measure demanding nursing care can’t handle large amounts no suction

Closed drains closed system - bacteria can be minimised skin - effluent diverted away easy to measure easier to nurse can handle large amounts suction available stiffer - more traumatic

Drains

Using Drains

Decide on indication Decide on drain type Positioning Care - complications Removal

Drains - Indications Prophylactic

anticipated collection leak after anastomosis abscess wall continues to secrete

Therapeutic collection present pneumothorax, haemothorax liver abscess peritoneal haematoma

Body areaBody areahead/ neck /joints head/ neck /joints

small calibersmall caliberabdomen/thoraxabdomen/thorax

any caliberany caliber

Type of fluidType of fluidviscousviscous

large caliberlarge caliberirritatingirritating

closed systemclosed system

Amount of fluidAmount of fluidlarge amountslarge amounts

suction ± sumpsuction ± sump

Drains - Type

Drains - Position

Dependent

Not in contact with bowel if possible

Away from anastomosis

Never through main wound

Drains - Complications

Blockage Dislodge in or

out Viscera damage Skin infection Cavity infection

Drains - Care Check for blockage

ensure suction working empty containers

Ensure secure anchor Protect skin

keep dry dressing change

Cavity infection remove early antiseptic in collection container

Monitor amounts and type of fluid

Drains - Removal

Therapeutic indicationTherapeutic indication AmountsAmounts

abdomen/chest < 100mlsabdomen/chest < 100mls head/neck <20 mlshead/neck <20 mls

Imaging ensures cavity recoveredImaging ensures cavity recovered May remove in stages to allow collapse of cavityMay remove in stages to allow collapse of cavity

ProphylacticProphylactic Time of event has passedTime of event has passed

Case discussion

This is 20 year old male patient who had surgery a week ago

What has happened?

Signs & symptoms

Investigations?

Treatment?

Case 2