| April
2000
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Anaesthetics &
Medical Vivas
(from Helen Crilly)
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Medical
Viva
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Given
2 minutes to look at history, 9 minutes to examine, 1 minute
to wash hands and therefore have less than 5 minutes for
questions from examiners passes quickly!
CASE 1
Hx given: patient
with Chest pain and SOB
Hx from patient: cardiac
valvular lesion found on angiogram to investigate chest pain
Angiogram with normal vessels and decided no benefit with
CABG.
Palpitations. No
syncope. Exercise
tolerance 1 set stairs stops due to SOB.
Dx: Aortic Stenosis
Questions:
What Hx and Sx suggest a severe lesion?
What qualities of murmur would suggest severe AS?
Asked what Ix do you want?
Shown CXR asked if any evidence of LA enlargement.
CASE 2
Hx given: ญ
SOB & ฏ
Ex Tolerance in 48yr old man
Hx of being febrile given by examiners
Hx from patient: cough for 7 years.
Normally 3 tbsps per day.
Now approx ฝ cup daily.
Greenish yellow.
Hx intermittent infective exacerbation.
Life long non smoker.
Excellent exercise tolerance still but noted can do
less than usual recently.
Recent travel to UK
Recurrent sinusitis Sx x 2
RLL signs
Dx = bronchiectasis
Asked what Ix you would like to see
Shown CXR RLL changes
Asked about potential significance of Overseas travel
Recurrent sinusitis
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| Investigation
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Scenario: Male
in recovery post CABG with bleeding
What Ix would you like to see?
You give list then asked what abnormalities would be looking
for on each test?
FBC Hb and Platelets
Pl Aggregation tests: dysfunctional due to CPB
INR and aPTT
FDPs =? DIC
ACT = residual heparinisation
What is a normal ACT?
When would you normally check the ACT in the OT?
Given ACT = 120 secs
What would you want the ACT to be if you give heparin prior
to bypass?
If ACT > 150 secs, what would you do then? ฎ
protamine.
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Scenario: Right pneumonectomy who is 5/7 post op
Noted increased SOB and difficulty breathing through day
Ix wanted:
CXR right side of chest half filled with fluid
Left lung has increased vascular markings and upper
lobe re-distribution
Dx = fluid overload
ECG rapid AF and inferolateral ischemia
What is your management?
Mx = haemodynamically unstable
- DCS
Haemodynamically unstable amiodarone
Told that give amiodarone and shown another ECG which shows
SR and essentially normal.
2/7 later patient coughs up blood stained sputum plug and
becomes acutely SOB.
What do you think might have happened?
Bronchopleural fistula/disruption of pneumonectomy stump.
What is the DDx?
How would you assess this patient?
How would you manage this patient? ABC, ICC
What Ix would you want prior to OT?
Given CXR and ECG to look at.
Same scenario Dr John Pohs version
describe tests to assess coagulation status
coagulation profile( reference range ), ACT test, test for
fibrinolysis
when to give platelets and FFP
three ECG's
Chest X ray - fluid level postpneumonectomy
bronchopneumonia - microorganism in HIV patients
respiratory function test - severe obstructive airway
disease
draw flow volume loop for variable intrathoracic obstruction
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| Anaesthetic Vivas
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| Viva
1: A
30 year old, 130 kg primaparous woman with a breech
presentation presents at term for elective caesarean
section. Otherwise the pregnancy has been uneventful. She
requests regional anaesthesia for the procedure.
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What are the potential problems with inserting a RA?
What techniques would you use?
What anaesthetic agents would you use?
What level would you put the epidural in?
Would you put it in at L1/2?
The only good space is T12 / L1, would you put it in there?
What problems is there with T12 / L1 insertion cf other
levels?
Missed segments;
SC injury; High
block potential
What level of block need to impair respiratory muscles?
What level for motor block acceptable?
What sensory level acceptable?
What SNS level acceptable?
Institute block and able to use spinal with epidural
inserted for backup for long operation.
Develop hypotension BP
70/40 and bradycardia Mx.
What is the likely cause?
Secondary to onset of sympathetic blockade/ vasodilatation
Supine hypotension
What else would you like to do? ( all maternal monitoring
and Mx already discussed)
Monitor baby
2/7 post delivery develop postural headache what is the
likely cause? PDPH
What is the DDx?
How do you assess this patient?
What is the appropriate Mx?
How would you perform a blood patch?
Is there anything else you can do other than aseptic
technique to avoid potential for developing secondary
infection from the blood patch?
Wanted to discuss usefulness of performing blood
cultures when perform blood patch.
Same scenario Dr John Pohs version
technical
problems with performing regional blockade in obese patients
complications
how to locate space if difficulty with ascertaining the
iliac crest arises- positioning, X ray
technique used , drugs used for regional ( including dose )
postdural puncture headache - management
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Viva 2:
A 60 year old woman with a long history of rheumatoid
arthritis presents with increasing headache two weeks after
a fall and minor head injury. A CT scan shows that she has a
subdural collection with requires surgery.
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Discuss the anaesthetic implications of Rheumatoid
arthritis.
Wanted to discuss airway implications in depth.
Asked what Ix you would like for the airway.
Given C spine extension view normal.
Asked if want to check anything else given flexion view.
Abnormal flexion with 5 mm atlanto-axial subluxation
Pointed to calcified hyoid and asked what it was
How would you secure her airway?
What are the potential disadvantages of awake fibreoptic?
Wanted to discuss coughing/gagging.
How would you perform a fibreoptic intubation?
At end of operation when haematoma evacuated the surgeon
asks you to reexpand the brain! how could you do this?
How would you extubate this lady? I said allow to wake in
ICU prior to extubation
In ICU seizures 1 hour post extubation management?
Same scenario Dr Pohs version
anaesthetic
implications of rheumatoid arthritis,
cervical spine X rays ( extension and flexion views )
demonstrating cervical subluxation and altantioaxial
subluxation
management of difficult airway - fibreoptic intubation -
technique
ways to expand the brain after the clot has been evacuated
describe extubation the patient
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Viva 3:
You are an anaesthetist accompanying a surgical team to
procure the heart, liver and kidneys from a donor in a large
provincial town. On arrival in the Unit, the donor's
distraught spouse states that the right foot moved in
response to rubbing the heel. You are asked to certify the
presence of Brain death
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What are you going to do?
What do you say to his wife?
Asked how you would perform brain death testing.
If he sweats, could he still be brain dead? What about if he
breathes? What about hiccoughs?
You performed your own brain death testing and happy with
results. You were then told by the RN that Pancuronium was
still running what is your management?
Cease Pancuronium let NMBD wears off and repeat test.
How long before you are happy to proceed?
How would you confirm that there was no residual NMB? Nerve
stimulator
You complete testing and decide to proceed.
During the operation UO 500 mls/hr? What is happening? DI
Rx = fluid replacement and DDAVP 0.3 mg /kg
Unable to use DDAVP because surgeons concerned that may have
an adverse effect on the coronary arteries what else can
you use?
Patient becomes bradycardic and hypotensive Mx?
Likely diagnosis ? hypovolemia secondary to running dry with
head injury in ICU or secondary to raised ICP
What is your Mx?
Avoid ionotropes if possible tried ephedrine and
atropine = no effect
Commenced on adrenaline.
Asked what alternative iontrope may have been preferable.
Same scenario Dr Pohs version
moved his feet when subjected to painful stimuli. Describe
criteria for brain death.
anaesthetic management of patient undergoing organ
harvesting
differential diagnosis for polyuria ( 550 mis over last hour
) , diabetes insipidus
Pathophysiology and treatment, hazards associated with DDAVP
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| Viva
4:
You are working in a large rural base hospital and are
called to the emergency room where a 7 year old boy has been
brought in by ambulance following a house fire.
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How would you assess this child?
primary survey
Asked how to assess the extent of burns - Rule of 9s
What Sy and Sx may suggest airway burns?
How would you secure the airway?
RSI vs Inhalational discussion of risks vs
benefits
Told child is able to speak but mild stridor
Told that both legs, front torso and neck burnt.
Asked about contribution of head in child with respect to
BSA
Is there a formula to work out the % assigned to the head in
a child?
Fluid management: which rule?
How much, what type fluid and how do you give it? 4ml/kg/%BSA
burnt ฝ over 8hours then rest over 16hours +
maintainence
What other considerations are there?
Analgesia morphine dosage?
Child has CF -
taking back for debridement and SSG in OT.
What are the considerations?
Can be divided into those due to the procedure and those due
to
CF
Nutrition
Infection
Chest
Healing
How would the CF influence your postop care?
What other considerations?
Nutrition and catabolism
Other injuries trauma
CO poisoning
Same scenario Dr Pohs version
assessment of area burnt in a child, severity and
resuscitation,
parameter for assessing adequacy of resuscitation;
when does one consider transferring a patient to a
paediatric centre
airway management - features suggestive of inhalational
injury
patient for debridement and split skin graft - potential for
blood loss - how much
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Viva 5: A 75 year old 85kg female presents for revision total hip
replacement. Her relevant past history includes
osteoarthritis, high serum cholesterol, a single episode of
classical angina two years ago and an uneventful general
anaesthetic one year ago for carpal tunnel release. General
anaesthesia for primary hip replacement was uneventful. Her
activities are very limited by hip and knee pain and she has
experienced significant weight gain. Her only medications
are paracetamol and cholestyramine.
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What are the possible methods of minimising perioperative
blood loss?
Pre op
Check
for and correct coagulopathy
Stop
NSAID/aspirin
Autologous
transfusion
Iron,
folate
Intra op
Cell
saver
NVHD
Regional/epidural
Hypotensive
anaesthesia
Post op
Stryker
drains
Blood
loss
What influence would the patients angina have on the
decision to use autologous blood transfusion?
Need more details of IHD severity first
How do you investigate his IHD?
Standard ACC / AHA guidelines
For Autologous blood transfusion:
What Hb would you accept ?
Hct = 0.3
How would you calculate the amount of blood you could
remove?
Mls blood = Hct initial Hct acceptable x blood
volume
Hct
average
Why do you pick this Hct?
What are the problems of lowering the oxygen carrying
capacity of the blood?
What anaesthetic options are there?
What technique would you use ? GA or Epidural or combined ?
About 2 min after the insertion of the femoral prosthesis
flat pulse oximeter trace
What is your differential diagnosis?
Dx = cement implantation syndrome
DDx = anaphylaxis
Cardiac
arrest / ischaemic event
Embolism
- fat, pulmonary
What can you do to prevent this? Major control is surgical
technique
What factor could you do to minimize the impact of this
event?
Diligent watching
Preparation for the event
Adequate IV preload
Avoid hypoxia, acidosis and hypercarbia
Drugs etc ready
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Viva 6:
There
is a 4 year old boy with a history of nocturnal snoring on
your day surgery ENT list for adenotonsillectomy.
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Pre op assessment : OSA
Sx and Sy presents irritable, apnoea, poor growth
Right heart strain
URTI
What are the indications for removal of tonsils?
How else do these children present ? Recurrent ear
infections
Are you prepared to do this child in DSU?
Free standing or attached to main hospital ?
Hx given: child
snores but parents not aware of any apnoeic episodes.
Growing well. Good
appetite.
What monitoring would you give this child overnight if were
concerned re OSA?
Analgesic options?
Would you use PR dose of paracetamol? No
Why ? Poor and unreliable absorption, poor analgesic quality
What is in pain stop?
What is in liqugesic?
How would you induce this child?
Inhalational or IV
Would you use LMA?
What is your reason?
What induction agent and what dose?
Size of LMA and size of ETT?
Would you give this child morphine in recovery?
The child is vomiting in recovery what can you use?
What dose?
Given scenario of bleeding tonsil in recovery
What are the anaesthetic implications of this situation?
How do you induce?
Preparation for induction?
What if there is previous history of difficult intubation?
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Viva 7:
You are asked to transport a 40 year old patient from the
Intensive Care Ward (ICU) to the Radiology Department and to
manage the patient for a head CAT (Computerised Axial
Tomography) Scan. The patient is not intubated, breathing
supplemental oxygen, slightly confused but conscious. There
is an underwater chest drain in place.
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What are the issues that must be considered prior to
transporting this patient?
Staff
Facility
Patient
What are the factors to consider with remote Anaesthesia?
How do you set up a safe remote environment?
How would you design a safe environment to cope with a power
failure?
2 weeks later the patient is now well and
is booked for an MRI. The patient suffers with
claustrophobia what do you do?
Talk to patient and discuss options - Sedation Neurolept
GA
What particular risks are there in the MRI environment?
What is the cause of burns in the MRI?
Arrest in MRI Mx?
Same scenario Dr
Pohs version
Discuss preparation for such a undertaking and anaesthetic
considerations
If patient was to be transferred to a MRI room, discuss
anaesthetic
Implications - sedate vs GA, hazards of anaesthetising a
patient in MRI
Safety design features for an imaging room in case of an
electrical blackout alternative power supply, suction etc
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Viva 8:
A 54 year old woman who is a recovered alcoholic presents
for her fourth resection of recurrent benign laryngeal
papillomata. She is very hoarse and develops stridor when
trying to breathe quickly or deeply.
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How would you assess this patient?
Airway :
breathing is worst it has ever been
3
previous anaesthetics
Nil
problems before
But
cant lie flat this
time
None of previous anaesthetic records or techniques are
available to you.
What Ix would you do for inspiratory stridor?
Please draw the expected flow volume loop for this patient?
Airway management?
Asked re type and size of tube would use - laser flex tube
Awake FOB vs Inhalational
Discussion regarding spontaneous breathing unprotected
airway I decided would be safest to intubate this lady.
Would I jet ventilate No Why?
Same scenario Dr Pohs version
preoperative
evaluation
investigations
implication of laser surgery - anaesthetic technique, types
of laser tubes M
stridor and respiratory distress postop in recovery -
discuss differential
diagnosis and management
problems with tracheostomy
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Viva 9: A
65 year old male presents for trans urethral resection of
his prostate gland. He is a paraplegic following thoraco-abdominal
aortic aneurysm repair.
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What level of paraplegia is likely?
Told that the level is T5 paraplegia what problems are
there likely to be?
What is the supply to respiratory muscles?
What do the intercostals do?
What is the mechanism of Paraplegia?
Discuss the artery of Ademkowicz? Origin?
Blood supply of the spinal cord ? ASA x1 and PSA x2 etc.
Location of motor centers in spinal cord?
How are you going to anaesthetise this man?
Why did you choose this method?
Mechanism of Autonomic Dysreflexia?
Could you still get autonomic dysreflexia under GA?
What other anaesthetic approaches are possible other than
GA?
RA spinal
What are the potential problems with spinal anaesthetic?
Resp muscle compromise
During operation and given GA patient becomes hypertensive -
Mx?
Increase dept of anaesthesia..
พ way through develops hypertension and decreased
saturation?
Cause? fluid overload and ? TURP syndrome
You notice nurse has put up water instead of glycine
what do you do now?
Change to glycine, ABC, inform surgeon, stop
resection ASAP, check height of bag etc
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