Pre operative care Flashcards
Things that need to be addressed before surgery
Pre-operative assessment (pre-op) Consent Bloods (including groups and save / crossmatch) Fasting Medication changes Venous thromboembolism assessment
Pre op assessment
determine if they are fit to undergo specific operation
PMHx:
- co morbidities
- pmhx problems
PSHx:
- previous surgery
- previous adverse response to anaesthesia
DHx+A:
- current medication
- allergies
SHx:
- smoking
- alcohol use
- frailty status
examination:
- ask about fhx of sickle cell disease
- general examination is performed to look for cvs and resp disease
malnourishment
- BMI <18.5 may need dietician input and additional nutritional support before surery and durign admission
pregnancy
consider in all women of childbearing age
ASA grade
physical status of the patient for anaesthesia
given a grade to describe their current fitness level
ASA I – normal healthy patient
ASA II – mild systemic disease
ASA III – severe systemic disease
ASA IV – severe systemic disease that constantly threatens life
ASA V – “moribund” and expected to die without the operation
ASA VI – declared brain-dead and undergoing an organ donation operation
E – this is used for emergency operations
pre operative investigations
bedside:
- ECG
- Echo
- Lung Function test
bloods:
Hba1c (within the last 3 months for known diabetics)
ABG (if known or possible resp disease)
U+E (risk of AKI / taking diuretics)
FBC (anaemia, cvs, renal disease)
clotting testing: liver disease
*group and save: send off a sample of pt blood to establish their blood group. sample is saved in case they require a blood transfusion.
Group and save is only valid for a certain period (7 days) depending on local trust policy and afterwards they will require a repeat sample.
crossmatching:
taking a unit of blood of the shelf and assigning it to the pt incase they need it quickly. higher probabiltiy they will require blood products.
MRSA screening:
routine for all pt.
fasting before surgery
ensure an empty stomach during their operation.
6 hours of no food or feeds before operation
2 hours no clear fluids (fully “nil by mouth”)
When you assess an acutely unwell surgical patient, always consider whether there is any possibility they require emergency surgery. Acutely unwell surgical patients that potentially require emergency surgery are made nil by mouth and given maintenance IV fluids. Allowing them to eat and drink could have significant consequences if they need emergency surgery, and the anaesthetist and senior surgeon won’t be happy. This decision will often be reversed on the post-take ward round if the consultant or senior surgeon decides they are unlikely to need to go to theatre.
specific medication and pre-operative care
anticoagulants
local guidelines for medicine alterations before and after ops.
*anticoagulants
stop before surgery
monitor INR it patient takes warfarin and ensure it returns to normal before operation (can reverse with vit K)
reatment dose low molecular weight heparin or an unfractionated heparin infusion may be used to bridge the gap between stopping warfarin and surgery in higher-risk patients (e.g., mechanical heart valves or recent VTE), and stopped shortly before surgery depending on the risk of bleeding and thrombosis. DOACs (e.g., apixaban, rivaroxaban or dabigatran) are stopped 24-72 hours before surgery depending on the half-life, procedure and kidney function.
specific meds and pre op care
COCP (the pill)
Oestrogen-containing contraception (e.g., the combined contraceptive pill) or hormone replacement therapy (e.g., in perimenopausal women) need to be stopped 4 weeks before surgery to reduce the risk of venous thromboembolism (NICE guidelines 2010).
specific meds and pre op care
long term corticosteroids
equivalent to more than 5mg of oral prednisolone, require additional management around the time of surgery. Surgery adds additional stress to the body, which normally increases steroid production. In patients on long-term steroids, there is adrenal suppression that prevents them from creating the extra steroids required to deal with this stress. Management involves:
Additional IV hydrocortisone at induction and for the immediate postoperative period (e.g., first 24 hours)
Doubling of their normal dose once they are eating and drinking for 24 – 72 hours depending on the operation
specific meds and pre op care
*diabetes
The stress of surgery increases blood sugar levels. However, fasting may lead to hypoglycaemia. In general, the risk of hypoglycaemia is greater than hyperglycaemia.
Certain oral anti-diabetic medications may need to be adjusted or omitted around surgery:
Sulfonylureas (e.g., gliclazide) can cause hypoglycaemia and are omitted until the patient is eating and drinking Metformin is associated with lactic acidosis, particularly in patients with renal impairment SGLT2 inhibitors (e.g., dapagliflozin) can cause diabetic ketoacidosis in dehydrated or acutely unwell patients
specific meds and pre op care
*diabetes and insulin
Continue a lower dose (BNF recommends 80%) of their long-acting insulin
Stop short-acting insulin whilst fasting or not eating, until eating and drinking again
Have a variable rate insulin infusion alongside a glucose, sodium chloride and potassium infusion (“sliding-scale”) to carefully control their insulin, glucose and potassium balance
pre op care- VTE prophylaxis
Every patient admitted to hospital should be assessed for their risk of venous thromboembolism (VTE). Surgery, particularly where the patient is likely to be immobilised (e.g., orthopaedic surgery), significantly increases the risk of venous thromboembolism. There are local and national policies on reducing the risk that involve:
Low molecular weight heparin (LMWH) such as enoxaparin
DOACs (e.g., apixaban or rivaroxaban) may be used as an alternative to LMWH
Intermittent pneumatic compression (inflating cuffs around the legs)
Anti-embolic compression stockings
