Surgery Flashcards
Sepsis
Presence of pathogens
Asepsis
Free from infection
Antisepsis
Prevention of sepsis
Sterilisation
Elimination of all microorganisms including spores
Disinfection
Removal of all microorganisms, sometimes not including spores.
Bacterial infection
defined as having more than 10^5 bacteria per gram of tissue i.e. bigger than colonisation.
Classification of surgical wounds
- Clean
- Clean-contaminated
- Contaminated
- Dirty
Clean wound
Non-traumatic, non-inflamed operative wounds that do not enter respiratory, gastrointestinal, urogenital, oropharyngeal tracts.
E.g. elective neuter, THR
Infection rates = 0-4.4%
Clean-contaminated wound
Operative wounds in which respiratory, gastrointestinal, urogenital, oropharyngeal tracts are entered but under controlled conditions without unusual contamination.
E.g. bronchoscopy, enterotomy
Infection rates =4.5-9.3%
Contaminated wound
Open, fresh, accidental wounds or procedures in which GI contents or infected urine is spilled or a major break in aseptic technique occurs.
E.g. cystotomy with spillage of infected urine, open cardiac massage for CPR
Infection rates =5.8-28.6%
Dirty wound
Old traumatic wounds with purulent discharge, devitalised tissues or foreign bodies; procedures in which a viscus is perforated or faecal contamination occurs.
E.g. excision/drainage of an abscess, bullae osteotomy for otitis media, perforated intestinal tract
Gross infection is present
Circumstances in which antibiotics should be used prophylactically
- Surgery time longer than 90 mins
- Prosthesis implantation E.g. mesh, pacemaker, bone cement
- Patients with pre-existing prosthesis E.g. hip replacement undergoing certain surgical procedures
- Severely infected or traumatised wounds
Factors affecting the establishment of infection
- Host factors e.g. age, physical condition, nutritional status etc.
- Diagnostic procedures e.g. placing a catheter increases likelihood of an ascending infection
- Concurrent metabolic disorders e.g. HAC
- Medication e.g. corticosteroids, chemotherapy
- Operating room practice
- Aseptic technique
- Sterilisation, disinfection
- Anaesthesia
- Atraumatic technique
- Characteristics of bacterial contaminants
Discuss the rational use of antibiotics in the surgical patient
- Generally, antibiotics are used for contaminated/dirty wounds
- Sometimes they are used for clean-contaminated wounds
- Prophylactic use is rarely recommended, but may be indicated in specific circumstances
- Rational selection of antibiotics should be used
- Ideally this would depend on culture and sensitivity, but in practice time and financial constraints mean this isn’t possible
Give an example of an antibiotic that could be used for a patient undergoing large intestine surgery
- In this case we might be particularly concerned about anaerobes
- Metronidazole has good anaerobe coverage
Which should you use for cutting skin: scissors or a scalpel?
A scalpel
Scissors = poor practice, would crush the skin as they cut.
What is the most commonly used scalpel blade?
Number 10
Which scalpel blade should you use for the most delicate tissues? e.g. a urethrostomy
Number 15
Which forceps are considered the go-to for soft tissue surgery?
Debakey forceps
They were originally designed for vascular use and are the least traumatic of forceps
Here are some forceps. What are they used for?
Haemostat forceps
- Designed to occlude blood vessels and prevent haemorrhage
Here are some forceps. What are they used for?
Tissue holding forceps
- Designed to handle and manipulate tissues.
- Specific design varies according to relevant tissue.
Tensile strength
breaking strength per unit area.
i.e. how strong it is under tension
Memory
tendency to retain original configuration when it comes out of the packet.
Which has higher memory: monofilaments or multifilament? What does this mean?
Monofilaments have higher memory, making it potentially harder to tie secure knots.
