Pre Operative Optimisation Flashcards
What are each of the ASA Grades?
The America Society of Anaesthetists (ASA) Grade system calculates the risk of mortality during surgery based on a patient’s co-morbidities.
GRADE 1 - fit, healthy patient
GRADE 2 - mild systemic disease
GRADE 3 - moderate systemic disease
GRADE 4 - severe systemic disease, constant threat to life
GRADE 5 - moribund; unlikely to survive without procedure
What are each of the MALLAMPATI grades?
GRADE 1 - complete visualisation of the soft palate
GRADE 2 - visualisation of the entire uvular
GRADE 3 - visualisation of the base of the uvular
GRADE 4 - nil visualisation of the soft palate
Identify the investigations that are ordered as part of the pre-operative assessment (standard).
✔️ FBC - check for anaemia or thrombocytopenia
✔️ UECs - check baseline renal function and check for any electrolyte disturbances
✔️ LFTs - check baseline liver function
✔️ coags - check for any disturbances that may increase risk of surgery
✔️ group and hold + cross match - prepare for catastrophic bleeding
What are the components of the SECONDARY SURVEY which may need to be performed in an emergency surgery scenario?
A - allergies
M - medications (particularly clopidogrel, hypoglycaemic, OCP and warfarin)
P - past medical and surgical history
L - last meal
E - events surrounding injury
Identify and define the four types of surgical wounds.
CLEAN - controlled excision with no signs of inflammation or infection; no breach / entry of gastrointestinal, respiratory or urogenital tract
CLEAN-CONTAMINATED - controlled entry of gastrointestinal, respiratory or urogenital tract; spillage of contents or pre-existing inflammation / infection
CONTAMINATED - accidental wound; spillage / leakage of gastrointestinal contents; inflammation; removal or an internal organ
DIRTY - traumatic wound; pre-existing infection at time of surgery
Outline when prophylactic antibiotics are required in surgery and the most common regime.
Prophylactic antibiotics are usually indicated in urogenital, gastrointestinal or vascular surgeries.
Cephalexin 2g IV, 15 to 30 mins prior to skin incision.
Define BRIDGING.
Bridging is a technique in which one blood thinning medication is replaced with another to mitigate the risk of bleeding during surgery in a patient who is at high risk of clotting.
Bridging most commonly involves patients who require WARFARIN.
- Determine the bleeding risk of the procedure. If LOW, do not interrupt warfarin therapy.
- If bleeding risk of the procedure is HIGH, calculate the patient’s VTE risk.
- If VTE risk is LOW, interrupt warfarin therapy for 5 to 7 days prior to procedure, without commencing LMHW.
- If VTE risk if HIGH, interrupt warfarin therapy for 5 to 7 days prior to procedure, commencing LMWH subcutaneous, daily.
The surgery can go ahead if INR < 1.5
Identify when the following medications should be ceased: ✔️ clopidogrel ✔️ aspirin ✔️ NOACs ✔️ warfarin ✔️ hypoglycaemic agents (e.g. metformin) ✔️ subcutaneous insulin ✔️ COCP
CLOPIDOGREL - 7 to 10 days
ASPIRIN - 5 to 10 days
NOACS - 1 to 2 days before (depending on bleeding risk)
✔️ low bleeding risk - cease on day of surgery
✔️ moderate bleeding risk - cease one day prior to surgery + commence one day after surgery (total 2 days interruption)
✔️ high bleeding risk - cease two days prior to surgery + commence two days after surgery (total 4 days interruption)
WARFARIN - 5 to 7 days (bridging with LMWH if required, depending on bleeding risk)
HYPOGLYCAEMIC AGENTS - 24 hours + replacement with continuous IV insulin infusion + schedule procedures for the morning
SUBCUT INSULIN - continuous IV insulin infusion
COCP - 4 weeks + counsel for use of alternative contraception
Outline the recommendations for food and fluid intake prior to surgery.
SOLID FOOD - cease 6 hours prior to surgery
COFFEE + TEA - cease 6 hours prior to surgery
CLEAR FLUIDS - cease 2 hours prior to surgery
What are the components of the CHADSVASc score? How is this interpreted?
CHADSVASc is a risk stratification tool that calculates the risk of a patient experiencing a stroke / thromboembolism in the context of atrial fibrillation. This risk determines the appropriateness of considering oral anti coagulation.
C - congestive heart failure H - hypertension A - age > 75 years D - diabetes mellitus S - stroke previously V - vascular disease A - age > 65 years S - sex (female)
If score is 1 –> consider oral anticoagulation (warfarin or NOAC)
If score is 2 –> commence oral anticoagulation (warfarin for valvular AF; NOAC for non-valvular AF)
What are the components of the HASBLED score?
HASBLED is a risk stratification tool that calculates the risk of severe bleeding in a patient.
H - hypertension A - abnormal LFTs, renal function or coags S - stroke previously B - bleeding disorder L - labile INR E - elderly D - drugs (e.g. warfarin, NOCAs)
HASBLED should be weighed against CHADSVASc in patients undergoing elective surgery on warfarin / NOAC therapy.
