principles of surgery Flashcards
define antisepsis
prevention of sepsis by destruction or inhibition of microorganisms using an agent that may be safely applied to living tissue
define antiseptic
an agent that is applied to living tissue to destroy or inhibit microorganisms
define disinfectant
agent that is applied to inanimate objects to kill or inhibit microorganisms
define disinfection
removal of microorganisms but not necessarily the spores
define sepsis
presence of pathogens or toxic products in tissue of patient
define sterilisation
complete elimination of microbial viability including spores
non-sterile barriers on person during surgery
- scrub suit
- face mask
- surgical head masks
- shoes/shoe covers
scrud suit in surgery
a permeable barrier to microorganisms that reduces particulate shedding during surgery
surgical head covers
reduce shedding of bacteria from the hair
face masks
protect the wound from saliva droplets during speaking
3 physical methods of sterilisation
- heat
- irradiation
- filtration
heat sterilisation is dependent on
time and temperature
3 methods of heat sterilisation
- steam
- moist heat (boiling)
- dry heat
most widely used method of heat sterilisation
steam
moist boiling cons
can only reach 100* which is not sufficient to kill most spores
dry heat sterilisation how to
kills microorganisms by oxidative destruction
dry heat sterilisation can be used on
- glassware
- cutting instruments
- opthalmic instruments
- drill bits
- powders
- oils
3 methods of irradiation sterilisation
- gamma rays
- UV light
- high energy electrons
most effective sterilisation irradiation technique
gamma irradiation
filtration sterilisation used on what
- liquids
- gases
3 methods of chemical sterilisation
- ethylene oxide
- hydrogen peroxide gas plasma
- cold sterilisation
ethylene oxide can
destroy all bacteria, fungi and spores
ethylene oxide action
inactives cellular DNA stopping cellular reproduction
ethylene oxide cons
toxic, inflammable and irritant to tissues
ethylene oxide sterilisation how to
- soak at room temperature for 12 hours
- aerate and ventilate for 24 hours to allow ethylene oxide dissipation
hydrogen peroxide gas plasma action
- uses UV photons and radicals
- 50* temperature for 45 min
hydrogen peroxide gas plasma pros
nontoxic and quick
cold sterilisation cons
usually only disinfects
cold sterilisation how to
soak in disinfectant for 24 hours
3 ways to indicate sterilisation
- chemical
- biological
- temperature and pressure recordings
chemical indicators of sterilisation how
colour changes on exposure to a certain temperature or chemical
chemical indicators of sterilisation cons
dont show exposure time
biological indicators of sterilisation
spores which are more resistant to sterilisation than bacteria are put in as well then cultured to see if killed or not
biological indicators of sterilisation cons
take time to show if machine functional or not
temperature/pressure indicator of sterilisation
the temps/pressures are plotted on a graph during machine operation to show that requirements are met
prep of surgical site 3 steps
- hair removal
- prep of skin
- draping of patient
hair removal in patient prep is to
reduce bacterial contamination
sterile areas of the gown
- from chest to table height
- from above elbow to cuff
wounds are classified as
- clean
- clean-contaminated
- contaminated
- dirty
clean contaminated wound example
going into GIT without significant spillage
contaminated wound example
- major break in aseptic technique or major GIT spillage
dirty wound example
foreign body
3 grips for holding a scalpel
- pencil grip
- fingertip grip
- palm grip
mayo scissors
used for dense collagen rich tissue
metzenbaum scissors
used for delicate dissection
surgical haemorrhage can be
- primary
- delayed intermediate
- delayed secondary
primary surgical haemorrhage
bleeding starts immediately
delayed intermediate haemorrhage
bleeding within 24 hours of surgery, e.g ligature slipped
delayed secondary haemorrhage
bleeding after 24 hours post surgery. can be due to necrosis of blood vessles
4 types of haemostatic forceps
- halsted mosquito (small)
- kelly (medium)
- carmalt (large)
- kocher (large with rat tooth tip)
define electrosurgery
- diathermy
- electric current passed through tissue produces heat due to the tissue resistance
2 types of diathermy
- bipolar
- monopolar
monopolar diathermy
current flows between handpiece to the ground plate
bipolar diathermy
current flows between 2 bipolar forceps
monopolar diathermy pros
- can cut through tissue as well as coagulation
- can attach to a metal instrument
bipolar diathermy pros
- use less current
- reduced local tissue trauma
- reduced incidence of distant tissue trauma
- can be used in a wet surgical field
half hitch ligature
do 1 throw then another (square knot) tightened by sliding
natural fibre suture material con
- more likely to get an inflammatory reaction
- variable absorption
synthetic suture material pros
- less reaction
- predictable absorption
multifilament suture material pros
better handling and knot security
multifilament suture material cons
capillary action for bacteria
monofilament suture material pros
less tissue drag
monofilament suture material cons
weakens when crushed
example of synthetic absorbable multifilament suture material
vicryl
vicryl is made from
polyglactin 90
when synthetic multifilament suture material absorbed by
day 60-90
when does vicryl loose strength
- day 7 33%
- day 14 80%
- day 21 100%
2 examples of synthetic absorbable monofilament
- monocryl
- PDS 2
monocryl is made of
polyglecapron
monocryl absorbed at
90-120 days
monocryl strength lost days
- 7 days 50%
- 14 days 60%
- 21 days 100%
PDS 2 is different from monocryl as it has a
longer duration
PDS 2 adsorbed at
day 110-210
strength lost PDS2 when
- day 14 26%
- day 28 40%
- day 42 75%
synthetic nonabsorbable monofilament 3 examples
- prolene
- ethilon
- flexon
nylon % strength lost at 2 years
25%
nylon memory
high
high memory means (knot)
low knot security
synthetic nonabsorbable multifilament example 2
- catgut
- collagen
absobed time natural absorbable mutlifilament suture material
60-70 days