Pre-op assessment Flashcards
History
Full hx is important PMH - comorbidities (acute cardiac event) Respiratory disease (reduce risk of ischaemic events)
REnal disease
Endocrine disease
Drugs to stop
Clopidogrel – stopped 7 days prior to surgery due to bleeding risk. Aspirin and other anti-platelets can often be continued and minimal effect on surgical bleeding
Hypoglycaemics – see ‘Diabetes Mellitus’ below
Oral contraceptive pill (OCP) or Hormone Replacement Therapy (HRT) – stopped 4 weeks before surgery due to DVT risk. Advise the patient to use alternative means of contraception during this time period.
Warfarin – usually stopped 5 days prior to surgery due to bleeding risk and commenced on therapeutic dose low molecular weight heparin Surgery will often only go ahead if the INR <1.5, so you may have to reverse the warfarinisation with PO Vitamin K if the INR remains high on the evening before
Drugs to alter
Subcutaneous insulin – may be switched to IV variable rate insulin infusion, as discussed below
Long-term steroids – must be continued, due to the risk of Addisonion crisis if stopped If the patient cannot take these orally, switch to IV (a simple conversion rate is 5mg PO prednisolone = 20mg IV hydrocortisone)
Drugs to start
Low Molecular Weight Heparin – the admitting doctor should complete a VTE Risk Assessment and prescribe appropriately Most patients will receive this, with the exception of those with either contraindications or who are having neck or endocrine surgery
Patients undergoing major GI surgery for cancer (including oesophageal, gastric, pancreatic, liver and colonic resections) and lower limb joint replacement should be discharged with TEDs and 28 days of prophylactic dose low molecular weight heparin (in the absence of contraindications).
TED stockings – all patients (with the important exception of vascular surgery patients) will receive below knee TED stocking. These need to be prescribed but check for contraindications (especially in the elderly). Contraindications include severe peripheral vascular disease, peripheral neuropathy, recent skin graft, severe eczema.
Antibiotic prophylaxis – patients having orthopaedic, vascular, or gastrointestinal surgery will require prophylactic antibiotics. Generally, these will be prescribed by the anaesthetist or the surgeon but if in any doubt, call your senior to discuss
Bowel Prep
Left hemi-colectomy, sigmoid colectomy, or abdo-peroneal resection: Phosphate enema on the morning of surgery
Anterior resection: 2 sachets of picolax the day before or phosphate enema on the morning of surgery
fbc
full blood count, predominantly used to assess if there is undiagnosed anaemia or thrombocytopenia,
us and es
To assess the baseline renal function of the kidneys, which will indicate potential co-morbid status
Clotting Screen
deranged coagulation, such as iatrogenic causes (e.g. warfarin), inherited coagulopathies (e.g haemophilia A/B), or liver or renal impairment, will need identifying and correcting before surgery
ECG
An ECG is often performed in individuals with a history of cardiovascular disease or for those undergoing major surgery. It can indicate any underlying cardiac pathology and provide a baseline if there are post-operative signs of cardiac ischaemia.
Airway assessment
Their degree of mouth opening (favourable if inter-incisor distance is above 3cm).
Their teeth, mainly do they have teeth? If so, what is their dentition like? Are any teeth loose?
Their oropharynx. Ask the patient to maximally protrude their tongue. A Mallampati classification (Fig. 2), which correlates with difficulty of intubation, can be assessed.
Lastly, assess the neck. Ask the patient to flex, extend and laterally flex the neck to see their range of movement. Then, ask the patient to maximally extend their neck and measure the distance between the thyroid cartilage and chin (the thyromental distance); if this is less than 6.5cm (~3 finger breadths), it indicates that intubation may be difficult.
Afro-Carribean
Sickle cell test
For DM
HbA1C if >6mmol then discuss
How long before surgery should they have pre-op assessment
2-4wks
Test for women of reproductive age?
pregnancy
What classification used to assess difficulty for intubation?
Mallampati scoring
