Anaesthetics - Pre-op Assessment Flashcards
what is important to think about in regards to anaesthetics and the elderly?
May present with many comorbidities and polypharmacy
Elderly has reduced physiology reserve in most systems
Cognitive decline is something to think about when assessing these patients
what may the trauma of syrgery be?
- Stress response (Anatomical and physiological changes in surgery)
- Fluid shifts
- Blood loss
- Cardiovascular, respiratory, renal and metabolic stress
what are the effects of general anaesthesia?
- Drug induced reversible coma
- CNS, cardiac and respiratory depression
- Drug interactions (between anaesthetics and patients durgs)
what deos Regional anaesthesia (e.g. epidural) cause?
- Profound sympathectomy
- Neurological sequelae
whata re some considerrations in anaesthetics?
- Patient - Known co-morbidities and Unknown pathologies (may not know the patient has these)
- Nature of surgery (different types of surgery)
- Anaesthetic techniques
- Post-op care
what is the role of the anaethatist pre-op?
- Assess
- Identify high risk (pick out patients that are high risk of perioperative complications, morbidity, mortality)
- Optimise
- Minimise risk
- Inform and support patients decisions
- Consent
why do a pre-op asessment?
Reduces:
- Anxiety
- Delays
- Cancellations
- Complications
- Length of stay
- Mortality
when should you do a pre-op assessment?
elective planned surgery - either in primary care or in pre-assessment clinic - gives lots of time to manage conditions prior to surgery
urgert surgery (e.g. for cancer, still have time for assessment)
emergency surgery (e.g. RTA)
what is involved in a pre-op assessment?
History
Examination
Investigations
what information needs to be gathered in a pre-op asessment history?
• Known co-morbidities:
- Severity
- Control (e.g. well controlled asthmatic is different form a bad controlled one)
•Unknown co-morbidities:
- Systemic enquiry
- Clinical examination
•Ability of withstand stress (stress of surgery):
- Exercise tolerance (good way to test it)
- Reason for limitation
- Cardio-respiratory disease
- Drugs and allergies (what is the reaction)
- Previous surgery and anaesthesia
- Potential anaesthetic problems
- Airway
- Spine
- Reflux
- Obesity
- Rarities / Family history - Malignant hyperpyrexia, Cholinesterase deficiency
what may investigation be used for?
- Detect unknown conditions
- Diagnose suspected conditions
- Severity of known disease
- Establishing a baseline
- Detecting complications
- Assessing risk
- Guiding management
- Documenting improvement
CVS and respiratory systems are the main ones we are interested to look at as anaesthetists:
what tests could we do to investigate the cardiovascular system?
ECG
Exercise tolerance test
Echo
Myocardial perfusion scan
Stress echo
Cardiac catheterisation
CT coronary angiogram
CVS and respiratory systems are the main ones we are interested to look at as anaesthetists:
what tests could we do to investigate the respiratory system?
Saturations
ABG
CXR
Peak flow measurements
FVC/FEV
Gas transfer
CT chest
what do you need to think about when choosing an investigation and who is getting them?
- Sensitivity and specificity
- Target those at risk
- Iatrogenic harm of over-investigation
What are the NICE guidelines on what we would look for in a patinet when choosing what investigation to use?
- ASA grade
- Surgery grade
- Co-morbidities
what are the ASA grades? (Scale we use to see how fit or unwell a patient is)
ASA1 - Otherwise healthy patient
ASA2 - Mild to moderate systemic disturbance
ASA3 - Severe systemic disturbance
ASA4 - Life threatening disease
ASA5 - Moribund patient
(ASA6 - Organ retrieval)
what are some risk assessment tools?
GUPTA perioperative cardiac risk
Geriatric sensitive perioperative cardiac risk index
Surgical outcome risk tool
American college of surgeons surgical risk calculator
STOP-BANG questionnaire
Nottingham hip fracture score
P-POSSUM
CR-POSSUM
Q-POSSUM
V-POSSUM
Postoperative respiratory failure calculator
Many many more
Each one may look at different things
one rik assessment tool we do commonly use along side ASA grading is the cardiac risk index
it is a list of conditions which you get a point ofr each of the things and if you have 2 or more points you are classed as high risk
what are the things on the list?
- High risk surgery
- Ischaemic heart disease
- Congestive heart failure
- Cerebrovascular disease
- Diabetes
- Renal failure
Exercise tolerance - METs (Metabolic equivalent score)
Subjective as your asking the patient as often overestimate what they can do so they can get the surgery that they want
what are the different MET scores?
Can you do the following activities without getting breathless;
- Walk around the house - 2 METS
- Do light housework - 3 METS
- Walk 100-200 metres on the flat - 4 METS
- Climb a flight of stairs or walk up a hill - 5 METS
- Walk on the flat at a brisk pace - 6 METS
- Play golf, mountain walk dance, or any form of exercise - 7 METS
- Run a short distance - 8 METS
- Do either strenuous exercise or heavy physical work - 9 METS
what is becoming the gold standard test and can be seen in the picture here?
Cardiopulmonary exercise testing
Assess fitness of patient for surgery
ultimatley what we are doing this assessment for through history, examinations and investigations is really to see if there is anything that we can optimise
can we improve the situation at all
what things may we be able to optimise?
Optimal medical control:
- Hypertension
- Ischaemic heart disease
- Heart failure
- Asthma
- COPD
- Diabetes
- Epilepsy
what lifestyle factors can we alter and look at in the pre-operative clinic?
Smoking - respiratory complications and wound healing
Alcohol - risk of infection and septic shock - Cessation of alcohol – no reduction in mortality but reduction in complications (dose dependant)
Obesity (losing weight before surgery improves outcomes)
Exercise (improving the amount the patient exercises improves the outcomes)
what is Pre-habilitation?
Improved fitness = improved outcomes
15% reduction in mortality risk per MET
Prescribing exercise! (prescribing exercise in peri-operative period to improve chances)
what is the process of dealing with a high risk emergency patient?
Informed consent
Anaesthetic plan
Invasive monitoring
Senior management
Post operative critical care
Pre-op medication - what do we do with the patients medication before surgery?
Most continue as normal
some especially have to continue as normal but there is some possible exceptions that may have to stop
what medications need ot be conitued?
Inhalers
Anti-anginals
Anti-epileptics
what medications may not need to be continued during surgery?
Anti-diabetic medication (depends what kind, what surgery, how well diabetes is controlled, when is the surgery, etc)
Anticoagulants
Summary?
Considerations:
- Patient
- Surgery
- Anaesthesia
Pre-op assessment:
- History
- Examination
- Investigations
Risk assessment
Optimising (optimisation of risk reduction)
Ultimately wanting informed consent form the patient
