Asepsis/ sterility Flashcards
Definition of asepsis
absence of pathogenic microorganism (within hospital environment)
Definition of sterility
absence of all living organism & spores in or on inanimate items
Definition of contaminated
carrying microorganism
Aseptic technique
rules/ protocol to prevent pathogenic organisms from gaining access & establish in surgical wound
Goal for aseptic technique
pathogen control & reduction of risk
Source of contaminants
Animal: secretion, nasopharynx, oropharynx
inanimate source: fomite, airborne
Methods of transmission
- contact
- droplets
- airborne
What is the most likely source of transmission of contaminants in surgery room?
personnel
What are resident bacteria?
normal flora on the patient
What are transient bacteria
- gain access to surgical site from within the operating room
- inanimated source
- animated source
Clean procedure
- do not enter organsystem
- no break in aseptic technique
- ex: overiohysterectomy, total hip replacement
What is clean-contaminated procedure?
- enters organ system
- minor break in aseptic technique
- ex: enterotomy, gastrotomy, lung lobectomy
What is contaminated procedure
- oral/ anal surgical procedure
- infected bile/ urine
- all traumatic wounds
- major break in aseptic technique
What is dirty procedure?
gross contamination or infection external trauma or perforation of a hollow viscus
components of aseptic technique
- isolate patients with infectious disease
- use PPE
- clean facilities & instruments between patients
- regular deep cleaning of environment
- minimize traffic
- washing hands
Components of sterile technique in the OR
Facilities & equipments
- cleaning & disinfection
- sterilization of the surgical pack
Patients
- preop clipping & scrubbing
Personnel
- maintaining sterility
What are disinfectants?
germicidal chemical substance that kill microorganism on inanimate
What to do when preparing the surgical instruments & packs
- sterilized in surgical packs
- marked with an expiration or sterilization date
- store appropriately
What clipper blade should we use for surgically prepping the patient?
40 blade
What is the intended incision landmark?
xiphoid to pubis
where are the drapes placed during abdominal surgery?
- cranial to xiphoid
- caudal to pubis
- mammary gland
What are the margins to clip?
- extend onto thorax
- caudal to pubis
- flank folds
Goals of the rough scrub
- remove organic debris
- reduce the numbers of pathogenic organisms
What should surgical antiseptics ideally be like?
- kill wide spectrum
- hypoallergenic
- no cutaneous absorption
- strong residual activity
What does isopropyl alcohol do?
- rapidly denatures cell wall protein, DNA, RNA
- widely effective against most microorganisms
- good immediate action
- no residual action
Shortcomings of using isopropyl alcohol
Highly irritating: corneas, wounds, mucous membrane
Chlorhexidine
- disrupt cell membrane, precipitate cell components
- activity
- excellent residual activity
- common
What is chlorhexidine effective against?
gram +. gram - , fungi
- less active against Mycobacteria
Why does chlorhexidine have long residual activity?
binds to keratin
Shortcoming of chlorhexidine
neurotoxin, toxic to cornea & eye
What is chlorhexidine used for commonly?
- 4% pre-surgical scrub
- 0.05% for mucous membranes & open wound
Function of povidone-iodine
iodinates, oxidizes cell component molecules
characteristics of Povidone-iodine
- widely effective against most microorganism
- activity reduced by organic debris
- good residual activity
Short-coming of povidone-iodine
- skin irritation
- thyroid dysfunction over time
What is the goal for preputial wash
remove exudate and reduce bacterial load
What is preputial wash?
- 2-minute flush
- chlorhexidine 0.05% more effective
- chlorhexidine cause less preputial irritation
What to do for patient preparation in the OR
final prep
Goal for sterile/ final prep
eliminate bacteria acquired during patient tranfer and new bacteria from patient pores/follicles
What does normal hand washing with soap
- will remove transient bacteria
- will not remove resident bacteria
What does mechanical scrubbing action and antimicrobial detergent
- will remove transient bacteria
- will remove resident bacteria
How long does it take to do surgical scrubbing
5 minute
