Exam 2022 Flashcards
What’s the sensitivity of 3 lead vs. 5 lead ECG?
lead II alone in 3 lead = 33%
Including a pre-cordial V5 = 75%
What type of genetic disorder is Haemophilia A?
X-linked recessive disorder
How to classify severity of Haemophilia A?
Mild - 5-25% factor level
Moderate 1-5%
Severe <1%
Carriers generally have >50% normal factor levels.
Clinical features of haemophilia A?
Haemarthrosis and muscle haematoma
- Joint damage, chronic joint pain, reduced mobility
Inhibitor presence - some people develop antibodies to the clotting factor treatment
- occurs in 20-30% of severe haemophilia A
Bleeding - gum/nose/urine
Pre-op optimisation of haemophilia A
Consider DDAVP 0.5mic/kg 30 mins prior to procedure
Recombinant factor VIII or cryoprecipitate
- Aim levels of 100% for 24-48 hours, 50% up to 1 week, 30% until wounds healed
Optimisation for haemophilia A if inhibitors are present?
immunosuppression with cyclophosphamide
Plasmapheresis
Intra-op anaesthetic considerations for haemophilia A
Major tertiary centre with blood bank/haem
Bleeding Mx: Cell saver, early declaration of major bleeding.
Potential contraindication of neuraxial
Avoid sux due to haemarthrosis
Early use of TXA
Minimise trauma during intubation
Measures to reduce environmental N2O impact
Efficient administration - minimise flow rate
Proper scavenging system - collect waste gas
Catalytic destruction systems - break down to N and O prior to releasing to atmosphere
Staff education on proper use
Decommissioning leaking N2O manifolds / pipelines
What’s class I to V in the NASPE pacemaker classification
I - chamber paced
II - chamber sensed
III - response to sensing
Iv - programmability or rate modulation
V - anti-tachyarrhythmia
What are the letters assigned to class I and II in PPM classification
O
A
V
D
What are the letters assigned to response to sensing
O = none
T = triggered
I = inhibited
D = dual (triggered & inhibited)
What is class IV of rate modulation?
Heart rate can increase with exercise.
Sensors reprogram pacemaker depending on demand.
Accelerates on exertion
When do you have to reprogram a device?
Surgery within 15cm of the device
Pacemaker dependent
Unable to place magnet due to positioning or location of surgery.
What’s the downside of bronchial blocker in a pneumonectomy?
Within staple line for pneumonectomy -> must be withdrawn prior to bronchus ligation.
More likely to contaminate healthy lung
More likely to be displaced.
What’s the limit set on fluid for pneumonectomy
Restrictive
Positive fluid balance should not exceed 20ml/kg in the first 24 hours.
Ventilation strategy for OLV
Lung protective ventilation
- Low TV 5-6ml/kg of ideal body weight
- Optimal PEEP
- Low plateau <30
- Driving pressure <15
- Recruitment only when necessary
- Tolerate hypercapnia
if desaturating on OLV, steps?
100% FiO2, check tube position, suction
Apply PEEP up to 10cmH2O to ventilated lung
CPAP to non-ventilated lung
Reinflate
Clamping of pulmonary artery, HFJV
How to manage the period of pulmonary artery clamping in pneumonectomy
Issue - shunt of blood supply to non-operative lung
Can result in significant increase in RV pressure and RV failure.
Picked up by an increased CVP
What’s the sensitivity and specificity of lung sliding detecting on US?
Absence
- 95% sensitivity, 100% specificity for pneumothorax
What’s the sensitivity and specificity of eFAST?
78.9% sensitivity
99.2% specificity
Low sensitivity, high specificity for intra-abdominal pathologies
High for both for intra-thoracic pathologies
BP target for descending aorta dissection
Ideally SBP 110-120mmHg
MAP 60-75mmHg
Limit of <140/90
Criteria for surgery for type B aortic dissection?
Persistent pain
Peripheral ischaemia
Rupture
Renal complication for TEVAR?
how to mitigate?
AKI due to graft obstruction, contrast use.
Mitigate by limiting contrast
Graft selection - use of chimney graft
Other complications of TEVAR?
Bleeding - need to open
Femoral artery injury
Embolic stroke - discuss use of heparin
Bowel ischaemia and lower limb ischaemia - 30 minly blood gases for rising lactate
ALS drug dose for neonate
adrenaline 10microg/kg
amiodarone 5mg/kg
O2 concentration for neonate during ALS?
21% for term infants
up to 30% for preterm
Increase O2 to 100% only if HR < 60bpm
Oesophagectomy surgical approach?
Ivor Lewis - laparotomy, R) thoracotomy
Need a DLT
4Ms of cancer?
Mass, metabolic, metastasis
Medication: chemo cisplatin (cardio and hepatotoxic, nephrotoxicity)
Management of migraine?
Non-pharm: psychosocial support, sleep hygiene, avoid alcohol.
Simple analgesia +/- antiemetic, triptan.
Preventative: beta-blocker, TCA.
Clinical feature of hepatopulmonary syndrome
AV shunt in pulmonary circulation
Dyspnoea improves by lying down
Limitation of cricothyroidotomy with scalpel-bougie-tube technique
Anatomical variation (trachea not midline)
Difficult if obese
Not a long term ventilating strategy -> convert to tracheostomy with ENT availability
Equipment requirement
IABP timing / how to tell when to inflate / deflate?
Match with patient’s rhythm via ECG or arterial pressure waveform.
o Typically commence at 1:1 augmentation ratio, i.e every beat is augmented.
o Can gradually wean to 1:2 or 1:3 ratio i.e augment every second or third beat.
IABP - magnitude to effect is dependent on?
o Balloon size vs. aorta size.
o Aortic compliance
o Heart rate (ineffective at HR > 130bpm)
o Heart rhythm (ineffective if non-sinus)
o Patient’s cardiac index (ineffective if <1.2)
Elements of procedural fairness
Notify parties about proceeding
Opportunity to be heard
Impartial decision maker
Reasons for decision
Right to appeal
HbA1c cut off to proceed with surgery?
8%
Safety precautions in MRI suite
- removal of ferromagnetic objects .
- screen for body implants.
- MRI safety zones
- Long extension lines for infusions in Faraday cages
- Reduce radio-frequency heating: avoid direct skin contact with coil, metal, ECG leads.
- Loud noises -> ear plugsD
Dose of intranasal dexmed in children>?
3 microg/kg
