Surgical Site Infections Flashcards
What are SSIs?
+ Infections occurring in a wound created by an invasive surgical procedure
+ Responsible for ~20% of HCAIs
+ 5% of patients undergoing surgery develop an SSI
+ Can double length of hospital stay
+ Associated with high morbidity
What are some different types of SSIs?
\+ Wound discharge \+ Dehiscence \+ Lymphadentitis \+ Abscesses \+ Necrosis (tissue or fat) \+ (Gas) gangrene \+ Sepsis \+ Induration \+ Purulent discharge
What are possible consequences of SSIs?
+ Microbial penetration of deeper tissue
+ Invasion of bloodstream (bacteraemia, sepsis)
+ Spread of bacteria to other sides (e.g heart valves, bones, peritoneum)
How, why and when do SSIs occur?
+ Contamination of incision by normal microbiota
+ Damage to tissues
+ Damage to blood vessels
+ Presence of foreign bodies (e.g sutures, implants)
+ Reduced efficacy of inflammatory response
+ Before, during and afer surgery
What are factors that infuence the development of SSIs?
\+ Type of surgical wound (clean/dirty etc.) \+ Pre-, intra- and postoperative care \+ Surgical team \+ Age and general health of patient \+ Extent of tissue injury \+ Infection prevention procedures \+ Presence of prosthesis or foreign body \+ Presence or absence of drain \+ Duration of surgery \+ Place in operation list
What are the classifications of surgical wounds?
\+ Clean (class I) \+ Clean/contaminated (class II) \+ Contaminated (class III) \+ Dirty (class IV)
What are the features of class I surgical wounds?
+ Elective surgery
+ No accute inflammation
+ Don’t involve R, GI or GU tracts
What are the features of class II surgical wounds?
+ Urgent/emergency case
+ Clean wounds with higher risk of infection
+ Uncomplicated R, GI or GU surgery
What are the features of class III surgical wounds?
+ Outside object comes into contact with wound
+ Large amounts of spillage from GI tract into wound
What are the features of class IV surgical wounds?
+ Purulent inflammation
+ Foreign object lodged in wound
+ Traumatic or infected wounds
What is the incidence of SSIs without antibiotic prophylaxis?
Class I - 2%
Class II - 6-9%
Class III - 13-20%
Class IV - 40%
What is the incidence of SSis with antibiotic prophylaxis?
Class I - 2%
Class II - 3-4%
Class III - 6-7%
Class IV - 7-16%
What are microbial causes of SSIs of the skin?
+ Staphylococcus aureus
+ Streptococci spp.
+ Enterococci spp.
What are microbial causes of SSIs of the bowel?
\+ Escherichia coli \+ Bacteriodes fragilis \+ Clostridium perfringens \+ Enterococci spp. \+ Anaerobic cocci
What are some forms of pre-operative care?
+ Pre-operative showering
+ Do not remove hair
+ Give antiobiotc prophylaxus before:
- clean surgery (prosthesis/implant only)
- clean-contaminated surgery
- contaminated surgey
+ Do not routinely use nasal decontamination
+ Do not routinely use mechanical bowel preparation
What are some forms of intra-operative care?
+ Surgical team hand decontamination
+ Do not use non-iodophor-impregnated incise drapes
+ Wear sterile fown and 2 pairs sterile gloves
+ Prepare skin at surgical site immediately before incision
+ Maintain patient homeostasis
+ Do not use wound irrigation or intracavity lavage
+ Do not use intra-operative disinfectant or topical antibiotics
+ Cover incisions with appropriate dressing at the end
What should be disinfected to minimise SSIs?
+ Hands of ward staff
- non-antimicrobial soap
- ABHR
+ Hands of surgical team
- scrub with aqueous antiseptic surgical solution before first op.
+ If not visibly soiled, subsequently use ABHR or antiseptic surgical solution
+ Patient’s skin
- alcoholic chlorhexidine
- povidone iodine
What are the two types of dressings that can be used to prevent infection?
+ Conventional
+ Occlusive
What do conventional dressings include?
+ Gauze
+ Tulle gras
+ Non-adhesive fabrics
What do occlusive dressings include?
+ Hydrocolloids
+ Polyurethane films
+ Foams
What are examples of good post-operative care?
+ Use appropriate dressings
+ Use aseptic or non-touch technique to change/remove dressings
+ Use sterile saline for wound cleansing up to 48hrs after surgery
+ Do not use topical antimicrobial agents for wound healing by primary intention
+ Follow guidance regarding use of debriding agents
How can the risk of post-op infections be reduced?
+ Keep pre-op length of stay in hospital to minimum
+ Treat any current infections before surgery
+ Keep length of surgery as short as possible
+ Maintain good operative technique
+ Debridement of dead/necrotic skin
+ Establish good blood supply
+ Prevent pressure sores
+ Arrange active physiotherapy to minimise risk of URTIs and UTIs
What precautions can be taken to prevent catheter-related infections?
+ Always wash hands before procedure
+ Wear gloves when handling catheter
+ Use single use antiseptic wipe
+ Cover insertion site with dressing
What are early presentations of prosthetic joint infections?
Early < 1 month:
- fulminant with wound sepsis
What are delayed presentations of prosthetic joint infections?
Delayed < 1 year:
- indolent, low grade infection
What are late-onset presentations of prosthetic joint infections?
Late-onset > 2 years:
- septic arthritis
How can a prosthetic joint infection be diagnosed?
\+ Blood culture \+ Collection of pus by needle aspiration \+ Bone biopsy \+ Raised ESR and CRP \+ Polymorphonuclear leucocytes \+ Radiological imaging
