pre-op assessment and prep Flashcards
trauma of surgery on patients
stress response
fluid shifts
blood loss
CVS, resp, renal and metabolic stress
what is general anaesthesia and what needs to be considered
drug induced reversible coma
CNS, cardiac and resp depression
drug interations
what is regional anaesthesia and what needs to be considered
e.g. spinal anaesthetic, epidural
profound sympathectomy
neurological sequelae
considerations when anaesthetising a patient
patient - known comorbidities, unknown pathologies
nature of surgery
anaesthetic techniques
post-op care
what is the role of an anaesthetist pre-op
assess patient identify high risk - peri-op complications and mortality optimise co-morbidities minimise risk of morbidity and mortality inform and support patient consent
why is doing a full assessment supporting the patient important
reduces: anxiety delays cancellations complications length of stay mortality
when is a pre-op assessment done
elective planned surgery - 1y care (wks-mths before surgery) , pre-assessment clinic (6-8wks before surgery) - time to improve pre-existing conditions etc
urgent surgery - 2-3 wks, still opportunity for assessment and optimisation
emergency surgery
what is involved in the pre-op assessment
hx
examination
investigations
hx in pre-op assessment - what do we ask about
known co-morbidities - severity, level of control
unknown co-morbidities - systemic enquiry, clinical examination
ability to withstand stress - exercise tolerance, reason for limitation, cardio-resp disease
D+A - sensitivity or true reaction
prev surgery and anaesthesia - any problems
potential anaesthetic problems
examples of potential anaesthetic problems
airway
spine - prev surgery or deformities
reflux - no fasting, intestinal obstruction
obesity
rarities/FHx - hx of family problems w/ anaesthesia - malignant hyperpyrexia, cholinesterase deficiency
reasons for investigations in pre-op assessment
detect unknown conditions diagnose suspected conditions severity of known disease establishing a baseline detecting complications assessing risk guiding management documenting improvement
cardiovascular investigations in pre-op assessment
tests done depend on the patient and the op e.g. fit 20 y/o vs 80y/o
ECG exercise tolerance test echo myocardial perfusion scan stress echo cardiac catheterisation CT coronary angiogram
resp investigations in pre-op assessment
saturations CXR ABG peak flow measurements FVC/FEV gas transfer CT chest
things to consider w/ investigations in pre-op assessment
sensitivity and specificity
target those at risk
iatrogenic harm of over-investigating
NICE guidelines for investigations required
ASA grade
surgery grade
co-morbidities
investigations are tailored to the specific patients for the specific surgery
ASA grading
used to identify how fit and healthy a patient is or how sick they are
1 - otherwise healthy 2 - mild to moderate systemic disturbance 3 - severe systemic disturbance 4 - life threatening disease 5 - moribound patient (6 - organ retrieval)
not fully specific for selecting pts w/ underlying/undiagnosed pathology
other 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 - obstructive sleep apnoea risk
nottingham hip fracture score
P-POSSUM
CR-POSSUM
Q-POSSUM
V-POSSUM
post-op resp failure calculator
revised cardiac risk index
point given for each: high risk surgery ischaemic heart disease congestive heart failure cerebrovascular disease DM renal failure
exercise tolerance - METS
can you do the following w/o getting SOB:
walk around the house - 2
light housework - 3
walk 100-200m on flat - 4
climb a flight of stairs/walk up a hill - 5
walk on the flat at a brisk pace - 6
play golf, mountain walk, dance - any form of exercise - 7
run a short distance - 8
strenuous exercise or heavy physical work - 9
can be subjective and pts may overestimate their ability
cardiopulmonary exercise testing
gold standard for assessing fitness of pts for surgery
requires more equipment, time and trained professionals
measures BCG, BP, o2 consumption
link between cardiopulmonary exercise testing and operative risk
anaerobic threshold correlates with risk of peri-op complications and morbidity and mortality
conditions to optimise pre-op
HT ischaemic heart disease heart failure asthma COPD DM epilepsy
lifestyle factors to consider pre-op
smoking - higher risk of resp complications, more chest infections, post-op problems, wound healing
alcohol - post-op infections
obesity
exercise
pre-habilitation
improved fitness = improved outcomes
15% reduction in mortality risk per MET
prescribing exercise
high risk emergency patients management
informed consent anaesthetic plan invasive monitoring senior management post-op critical care
pre-op medication
most continue as normal
esp: inhalers, anti-anginals, anti-epileptics
possible exceptions:
anti-DM (depends on the medication, who controls the DM, time of surgery, type of surgery, how quickly they will be able to eat afterwards etc)
anticoagulants (depends on type of medication and indication)
