1. Pre-operative assessment

2. Goals of preoperative assessment
History and physical examination to determine relevant tests and consultations
Guided by patient choice and medical risk factors choose a plan of care
Informed consent
Educate patient about anaesthesia, pain management and perioperative care
Reduce patient care costs

3. Questions
What is the risk of proceeding versus the benefit to the patient?
Can we modify these risks before surgery?

4. Mortality related to anaesthesia
Approx 1:26,000 anaesthetics
One third of deaths are preventable
Causes in order of frequency
inadequate patient preparation
inadequate postoperative management
wrong choice of anaesthetic technique
inadequate crisis management

6. Derivation and Prospective Validation of a Simple Index for Prediction of Cardiac Risk of Major Noncardiac Surgery Lee et al Circulation 1999;100:
Risk factor Criteria
High-risk surgery AAA repair, thoracic, abdominal surgery
IHD MI, Q on ECG, angina, nitrates, EST+
CCF History, examination, CXR
Cerebrovascular disease Stroke, TIA
Diabetes Insulin treatment
Renal impairment Creatinine >177 mol/L
Number of factors % population Major cardiac complications
% 0.5%
% 1%
% 5%
3 7% 10% % %

7. Risk and ASA classification

8. Coronary Heart Disease
Class I: Ordinary physical activity does not cause angina. Angina occurs on strenuous exercise only.
Class II: Slight limitation of ordinary activity. Angina occurs on walking or climbing stairs rapidly, walking uphill, walking or stair climbing after meals, or in cold, or in wind, or under emotional stress, or only during the first few hours after wakening. Angina occurs on walking more than 150 yards on the level and climbing more than one flight of ordinary stairs at a normal pace and in normal conditions.
Class III: Marked limitation of ordinary activity. Angina occurs on walking 75–150 yards on the level or climbing one flight of stairs in normal conditions and at normal pace.
Class IV: Angina on slight exertion; possible at rest.

9. History and physical are the most important assessors of disease and risk

10. Presenting complaint e.g. thyroid mass
Why does the patient need an operation now?
Is it acute/chronic illness?
Presenting symptoms?
e.g. anaemia, cachexia, pain, seizures etc
What are the pathophysiological consequences?
e.g. thyroid mass
Local - stridor, SVC obstruction
Systemic - hypo/hyperthyroidism

11. Associated medical conditions
Given the presenting problems are there any other conditions I am worried the patient could have?
Bowel ca. - liver mets with abnormal LFTs, abnormal coagulation, impaired drug metabolism
Peripheral vascular disease - IHD, carotid disease, HT, renal disease, COAD

12. Other medical conditions
Any other problems that may affect
perioperative morbidity and mortality?
cardiac disease
respiratory disease
arthritis
endocrine disease - diabetes, obesity etc
What is the patients functional capacity?

13. Functional capacity 1 MET Can you dress yourself?
4 MET Can you climb a flight of stairs?
10 MET Can you participate in strenuous activities (swimming, tennis,football)

14. Functional Capacity
All patients for major surgery should have METs > 4
Duke Activity Index
1 MET Can you take care of yourself? 4 METs Climb a flight of stairs or walk up a hill?
Eat, dress, or use the toilet? Walk on level ground at 4 mph or 6.4 km/h?
Walk indoors around the house? Run a short distance?
Walk a block or two on level ground
at 2 to 3 mph or 3.2 to 4.8 km per h? Do heavy work around the house like scrubbing floors or lifting or moving heavy furniture?
Do light work around the house like
4 METs dusting or washing dishes? Participate in moderate recreational activities like golf, bowling, dancing, doubles tennis, or throwing a baseball or football?
>10 METs Participate in strenuous sports like swimming, singles tennis, football, basketball, or skiing?

16. Anaesthetic history/assessment
Family history
Previous anaesthetics
PONV
allergy
malignant hyperpyrexia
difficult airway
difficult IV access

17. Airway assessment Best done by an anaesthetist
Certain features of concern
small mouth
poor dentition
limited neck mobility
scars/surgery/anatomical abnormalities
obesity

18. Mallampati scoring system

19. Why would this man’s airway
be difficult to manage?

20. Drug history Very useful, often forgotten Current medications ALLERGY
Medic alert bracelets
Smoking/alcohol history
Other drugs of abuse!

21. “The more tests, the better”

29. Perioperative medications
Take all usual medications
Antihypertensives
Beta blockers
Statins
Think about discontinuing/replacing
Aspirin
Anticoagulants
Diabetic medications
MAOIs

30. Summary add little in low risk patients may add false + ves
History and physical most important assessors of disease and risk
ASA and functional status good predictors of risk
Lab tests have some usefulness
add little in low risk patients
may add false + ves
add expense

31. Case example You are an orthopaedic House Surgeon
Your Registrar tells you
“ There is a fractured femur in ED, get it ready for theatre.”
What are you going to do?

33. Case example A 49 yr old Samoan woman presents for
elective hemicolectomy. She has a 10 yr
history of NIDDM . She takes glipizide
and metformin
What are you going to do?

34. Case example An 81 yr old man presents for elective
TURP. He has atrial fibrillation, has had
previous TIAs and is on warfarin.
What are you going to do?

35. Case example A 76 year old man with PVD presents for
femoro-popliteal bypass surgery. He has
an ejection systolic murmur on
auscultation.
What are you going to do?

36. Questions