Pre-operative

Question 1

What do NICE guidelines recommend for pregnancy testing and preoperative investigations?

Answer 1

On the day of surgery, all women of childbearing potential should be asked about the possibility they could be pregnant. Make sure those who are possibly pregnant are aware of the risks to the fetus and discuss about whether to carry out a pregnancy test.

Question 2

What do NICE guidelines recommend for sickle cell disease/trait tests pre-operatively?

Answer 2

Ask the patient whether there is FH of sickle cell disease as testing is not routinely done pre-operatively. If the person is known to have SCD, then liaise with their specialised team before surgery.

Question 3

Why is sickle cell and anaesthesia risky?

Answer 3

Associated with vaso-occlusive (painful) crisis, acute chest syndrome, post-operative infections, congestive heart failure, cerebrovascular accident and acute kidney injury.

Question 4

What do NICE guidelines recommend about HbA1c testing for non-diabetics pre-operatively?

Answer 4

Not recommended.

Question 5

What do NICE guidelines recommend about HbA1c testing for diabetics pre-operatively?

Answer 5

Offered to patients if their HbA1c has not been tested in the last three months.

Question 6

Why are diabetics at risk in surgery?

Answer 6

Greater risk of post-operative infection and cardiac problems.

Question 7

How are diabetics managed pre-operatively?

Answer 7

• Aim to achieve below 69 mmol/mol HbA1c
• Try to place patients first on list to minimise the fasting period (NBM)
• If diabetes is insulin treated, give all insulin the night before surgery
• If tablet-treated, give patient usual medications the night before surgery except those that cause prolonged hypoglycaemia e.g., sulfonylureas.

Question 8

What do NICE guidelines recommend about urine tests pre-operatively?

Answer 8

Only considered if the presence of a UTI would influence the decision to operate e.g. in frail elderly.

Question 9

What do NICE guidelines recommend about X-rays pre-operatively?

Answer 9

Not routinely offered.

Question 10

What do NICE guidelines recommend about ECGs pre-operatively?

Answer 10

Considered if patient has a heart murmur AND any cardiac symptom (including breathlessness, pre-syncope, syncope or chest pain), OR signs or symptoms of heart failure.

Question 11

Pre-operative management of patients on anticoagulants? (x4 parts)

Answer 11

Tell the surgeon as risk/benefit must be individualised. Avoid epidural, spinal, and regional blocks. Aspirin should probably be continued unless there is a major risk of bleeding. Warfarin can be continued in minor surgery but should be stopped 3-5d pre-op for major surgery.

Question 12

What should you do to re-warfarinize patients?

Answer 12

Initially give LMWH as warfarin is initially prothrombotic.

Question 13

Pre-operative management of patients on B-blockers?

Answer 13

Continue up to and including the day of surgery as this prevents a labile (easily altered) cardiovascular response.

Question 14

Pre-operative management of patients on Diuretics? (x2 parts)

Answer 14

Beware hypokalaemia and dehydration. Do U&Es (and bicarbonate).

Question 15

How is hypertension managed pre-operatively?

Answer 15

Treat if over 160/90 – disease optimisation.

Question 16

How is IHD managed pre-operatively? (x4)

Answer 16

Consider post-operative HDU; CXR if symptomatic or over 65yrs old; ECG is over 55yrs or poor exercise tolerance; manage HR and BP peri-operatively.

Question 17

How is asthma managed pre-operatively? (x3)

Answer 17

Identify and avoid potential triggers; maintain treatment regimen and consider additional medications/steroids; enquire about exercise tolerance. Asthmatics are at greater risk of bronchospasm and this is life-threatening.

Question 18

How is COPD managed pre-operatively? (x3)

Answer 18

Pre-operative optimisation through smoking cessation prior to surgery, physiotherapy in patients with large volumes of sputum, and invasive monitoring in GA surgery.

Question 19

What can you do to prepare a patient pre-operatively? (x9) SPAAACCRD “spaccered”

Answer 19

o Starve patient (at least 2hr fluids and 6hr solids)

o Bowel or skin preparation needed?

o Prophylactic antibiotics

o DVT prophylaxis – graduated compression stockings, LMWH.

o Anti-emetics are prescribed if necessary, for peri- and post-operative

o Analgesics are prescribed if necessary, for peri- and post-operative

o Site IV cannula

o If necessary, catheterise

o If necessary, insert Ryle’s tube (NG tube)

o SPAAACCRD “spaccered”

Question 20

How long should patients be starved for pre-operatively? Caveats?

Answer 20

Food: 6 hours; Water: 2 hours. Caveat: reflux, obesity, slow gastric transit time such as in trauma.

Question 21

How should an anaesthetic history be performed? (x7)

Answer 21

o Assess past history of: MI, diabetes, asthma, hypertension, rheumatic fever, epilepsy, jaundice

o Be alert to chronic lung disease, hypertension, arrythmias and murmurs

o Assess specific risks e.g. pregnancy, sickle cell disease.

o Drugs, allergies and recreational drugs

o Has there been previous anaesthesia? Were there any complications?

o Family history of anaesthetics and related co-morbities

o Loose teeth, contact lenses or metal inside patient?

Question 22

What examinations should be performed pre-operatively? (x4)

Answer 22

o Assess cardio system

o Assess respiratory system including exercise tolerance

o Assess airways

o Check neck and jaw mobility and stability e.g. arthritic complicating intubation

Question 23

What is the ASA pre-operative scoring system? (x5 classes)

Answer 23

CLASS I: normally healthy patient, CLASS II: mild systemic disease, CLASS III: severe systemic disease that limits activity but It is not incapacitating, CLASS IV: incapacitating systemic disease which poses a constant threat to life, CLASS V: moribund: not expected to survive 24h even with operation. NB: postscript E indicates emergency surgery.

Question 24

What is the POSSUM pre-operative scoring system?

Answer 24

o Physiological Parameters: age, cardiac failure (risk factors, cardiac drugs, JVP, oedema), dyspnoea, ECG, SBP, HR, Hb, WBC, Urea, Na+, K+, GCS

o Operative Parameters: operation type (minor, moderate, major, complex major), number of procedures, operative blood loss, peritoneal contamination (soiled with pus, bowel contents), malignancy status and CEPOD.

o Calculates a percentage risk for morbidity and mortality.

Question 25

How do you interpret POSSUM Scoring?

Answer 25

Over 5% mortality risk should result in HDU/ITU post-operative stay. 1% mortality risk is considered ‘high’.

Question 26

What is CEPOD?

Answer 26

Classification of Intervention – is it elective, urgent or emergency (within 2 hours)?

Question 27

How is an airway assessed pre-operatively? (x4)

Answer 27

o HISTORY: congenital or acquired airway difficulties e.g. Down’s, pregnancy, obesity, ankylosing spondylosis. Previous anaesthetic problems e.g. dental damage or sore throat

o EXAMINATION: adverse anatomical features such as small mouth, receding chin, large tongue, obesity. Is there reduced temporomandibular movement or poor C-spine movement? Dentition?

o RADIOLOGY: can predict the difficulty of intubation but not routine

o PREDICTIVE TESTS

Question 28

What predictive tests are there for airway assessment? (x7)

Answer 28

o Inter-incisor gap: with the mouth open maximally. Less than 3 cm makes intubation more difficult

o Protrusion of mandible: can protrude lower incisors anterior to upper incisors is good

o Mallampati test: open mouth maximally and protrude tongue – if you can see the uvula and soft palate (even if not uvula tip), then that is good

o Extension of the upper cervical spine: when less than 90%, laryngoscopy is more difficult

o Thyromental distance (Patil test): from tip of thyroid cartilage to tip of mandible with neck fully extended (normal >7cm)

o Sternomental distance (Savva test): from sternal notch to tip of mandible with neck fully extended

o Wilson score: combines weight, upper C-spine mobility, jaw movement, receding mandible and protruding upper teeth.

Question 29

What are the risk factors of difficult mask ventilation? (x8)

Answer 29

Age, BMI, history of snoring, beard, absence of teeth, facial abnormalities, receding jaw, OSA (apnoea).

Question 30

What is the criteria for suitability of patients for day surgery? (x3)

Answer 30

• Social criteria: patient consent, carer, home set up suitable
• Medical: fit, any chronic condition is stable, obesity not a preclude
• Surgical: general anaesthetic does not exceed 1h, complication risks low, mobile