surgical principles Flashcards
Where should a monopolar grounding plate not be placed?
Over a bony primonence, over a hairy or wet area, an area with an artificial limb, scar tissue, or distal to a prosthesis.
What energy is used in diathermy ?
alternating polarity radiowave electrical current.
What two settings does diathermy have and what is the difference in electrical energy ?
cut: vaporises the water content in tissue (low voltage)
coagulation: fulgurates (high volatage) dehydration of the tissues fulguration.
When would bipolar be optimal to be used over monopolar?
digits, pacemakers, spinal cord stimulators microsurgery
What are some (9) safety measures for safe electrosurgery practice?
Inspect insulation carefully
Use the lowest possible power setting
Use a low-voltage waveform (cut)
Use brief intermittent activation
Do not activate in open circuit
Do not activate in close proximity or direct contact with another instrument
Use bipolar electrosurgery when appropriate
Select an all metal cannula system as the safest choice
Utilize available technology (tissue response generator, active electrode monitoring) to eliminate concerns about insulation failure and capacitive coupling
describe monopolar and bipolar electrical systems
the active and return elecrodes are the key things to talk about.
the energy is generated in the generator, radiofrequency runs through the line
through the active electrode and then into the patients tissues.
in monopolar through the patient and back to the return electode
in bipolar it goes through the patient and into the return electrode is the other tip of the instrument
What the the maximum lateral thermal spread from bipolar diathermy?
5mm
monopolar spread can travel further
which is why bipolar is more suitable for delicate tissues.
the longer you keep the diathermy on the further the thermal injury will penetrate
how can injury be caused by electro thermal instruments
- direct application, inadvertent application of the the current to an non desired tissue.
- direct coupling: when the active electrode has contact with another material which acts as an active electrode for conduction potentially damaging structures
- capacitive coupling: electrical current in tissues or on metal instruments which runs parallel to but not in direct contact with the active electrode the electrical current is transferred from one conductive material (the active electrode) through intact insulation into adjacent conductive materials without direct contact.
- insulation failure. may provide an alternative flow for the path of electrical current
When would you expect bowel injury to present post electrothermal injury peri-operatively?
4-10 days later
Key areas for surgical infection control include? (4)
sterility of the instruments
good scrub technique
prophylaxic antibitoics
intraoperative adherance to infection control mechanisms
What are absorbable sutures used for?
bowel, small vessels under the skin, ureters.
what are some examples of absorbable sutures and indicate if they are synthetic or biological
Vicryl
vicryl rapide
PDS
monocryl
these are all synthetic
What are some examples of very slowly dissolving sutures vs very quick sutures
very slow PDS (200 days)
Very fast vicryl (42 days)
When would you use non absorbable sutures and what are some examples?
used to provide long teerm tissue support
remaining walled off by the bodys inflammatory processess
i.e tissues which heal slowly like tendons or fascia
closure of abdominal wall
vascular anastomoses.
Proline (synthetic)
stainless steel, and silk are (natural)
When would you not choose a braided vircyl?
infections
what type of needle would use for the following tissues?
skin
intestine
muscle
liver kidney friable tissues
skin: and other fibrous tissues, cutting or reverse cutting.
intestine: tapered needles
muscle: tapered, where minimal trauma is desired
blunt: fascia and delicate structures
What would be the clinical presentation of someone who has had inadvertant injection of local anaesthetic into the circulation? and what is the treatment?
parasthesia
light headeddness
cardiac arrythmias
IV lipid emulsion
what is the max dose of mg/ kg fo local with and without adrenaline?
with its 7 mg/kg
without its 3 mg /kg
NOTE: A 1% solution (of any substance) represents 10 mg/mL (1 g/100 mL).
What suture material has the highest tensile strength?
stainless steel wire then vicryl
What does good wound healing depend on?
good approximation of the health ytissue edges
no tension
no infection
good blood supply
adequate nutrition
What are some benefits to braided suture material?
high tensile strangth, they are more comfortable for patients, the knots lie easily and the material is better for handing.
What are some down sides to braided suture material?
the braided nature can increase friction and cause tissue trauma pulling it through, bacteria can harbour in the braided material, there are foreign particles which will lead to a greater immune response and more local inflammation and more scarring.
What are benefits of monofillament sutre material?
low friction as they pass through tissue, expands with tissue oedema, minimal trauma to the tissues as it passess through. flat waterproof surface which resists infection.
What are down sided to monofillament suture material?
they are more difficult to handle and they have memory so they boundback and can unwravel a knot. they need to be ties 7 times. the actual suture material can be damaged by for forcepts and adjacent delecate amretial canbe affected by them.
What is the suture material of choice for the vascular, cardiac and micro surgical tissues?
proline
When would staples be peferred to sutiures?
when there has been contamination i.e fecal peritonitis . fastest adn therefore are the best for quick use when you need to get the patient to ICU
how do you reduce injury to local structures during an operation
- excellent anatomical knowledge
- suitable planning of the surgical approach
- meticulous dissection technique
- careful retraction on vulnerable structures.
what are some acute common complications of giving someone PRBC? relevant for everyone getting the transfusion
hypothermia
hypocalcaemia
hyperkalaemia
clotting abnormalities, a dilutional effect.
what are some acute transfusion reactions? (5)
ABO incompatability
TACO
TRALI
mild to severe allergic reaction
sepsis
What is the management of a suspected ABO incompatability reactions?
stop the infusion
send off bloods for haptoglobin, haemoglobin, LDH, bilirubin and direct coombs test.
Gove IVH, 02 call the lab, seek specialist advice.
what is the management fo suspected TACO
they are fluid overloaded so give high flow 02 and fruse
what is the management of TRALI?
02 and ICU support
What can you give for a mild urticarial reaction to blood products?
antihistamine
What are some delayed responses to blood products?
BBV
graft vs host disease
iron overload
When would be an indication to give platelets?
plt < 50 , trauma massive transfucion, thrombocytopaenia with bleeding.
What is fresh frozen plasma and what is in it? when do you use it?
clotting factors
DIC, bleeding with lover disease, in major transfusion protocol after PRC
What is in cryoprecipitate and when do you use it?
von villebrand factor factor VIII and fibronectin
given with DIC fibrinigen < 1, VW disease and major haemorrhage.
What are three options for autologous blood transfusion?
preoperative donation
acute normovolaemia haemodilution
cell saver
What are the 4 pillars of surgical consent
patient has capacity
of free will
Consent is specific to this operation nothing else
consent is informed
What are important features of ascertaining if a patient has capacity?
a. understand information relevant to the decision in question
b. retain that information
c. use the information to make their decision
d. communicate a decision.
What is a framework you can use to challenge underperforming colleagues?
SPIES
S: seek information , from the person or colleagues
P: patient safety, while addressing the situation ensure patient safety, may need to remove the person from the situation.
I: initiative: what can i do to solve the problem.
Escalate: if the situation is too serious to other colleageus or seniors.
Support: reasons for the behaviour
