LE Exam Flashcards
Pharmacology of dabigatran?
competitive, reversible direct thrombin inhibitor
Immediate onset, peak effect at 4 hours, half life of 15 hours
Dose 110-150mg BD
Unsafe in CrCl < 30ml/min
How can dabigatran be monitored?
Thrombin clotting time
Though quantifying it is difficult.
If TCT is normal then you can be sure there is no effect
Reversal agent for dabigatran?
idarucizumab 2.5 - 5g dose
Management goals for patient with known hereditary angioedema
- Ensure usual medications
- Consider need for prophylaxis pre-treatment
- Careful with airway manipulation
- Extended post-op recovery to monitor for development of airway swelling
Treatment options for hereditary angioedema?
C1 esterase inhibitor concentrates
- Berinert
Icatibant - bradykinin receptor antagonist
Androgens - danazol (long term prophylaxis)
Anti-fibrinolytic agents - TXA, long term prophylaxis option
Electrolyte range for surgical to proceed for pyloric stenosis
Chloride > 100mmol/K
HCO3- < 28 mmol/L
Na > 135
Urine output > 1ml/kg/hr
Urine Cl >20mmol/L
What does COACHED stand for?
Compressions continue
Oxygen away
All others away
Charge the defibrillator
Hands off
Evaluate rhythm
Defib / disarm
Specific thyroid dysfunction in amiodarone induced thyroiditis?
- Type 1 vs. type 2
Type 1 = increased synthesis of TH
- Treat with prophylthiouracil
Type 2 = excess release of T4/T3 due to destructive thyroiditis
- Treat with steroids
Type 1 can worsen if amiodarone is discontinued.
What organs can be affected by cystic fibrosis?
Pancreas
Liver cirrhosis
Sweat gland deficiency - risk of hyperthermia
Infertility in males
Osteoporosis
Key points for history taking on patients with organ transplant?
Underlying pathology - is the disease still affecting patient?
Severity of condition - exercise capacity
Complication - acute and chronic rejections
Medical management - immunosuppression, recent changes to doses
Complications post lung transplant?
Acute rejection - non-specific symptoms (dyspnoea, cough, low grade fever), decreased lung function of >10% spirometry measurements
Chronic rejection - bronchiolitis obliterans (inflammation and scarring of bronchioles. “popcorn lung”)
Infection - aspergillosis
Induction key points for patients with lung transplant?
?RSI due to impaired airway reflexes and denervation. Implication of aspiration is extreme
ETT placement beyond the vocal cords is necessary to avoid stress on tracheal anastomosis
Aside from induction points, what are some of the management goals for lung transplant patients undergoing lap surgery
strict asepsis, avoid unnecessary lines
Immediate post-op extubation ideal
Caution with fluids and avoid overload
Why is thymectomy a treatment for myasthenia gravis?
Curative in 70% of cases
Treatments for myasthenia gravis
Pyridostigmine
Corticosteroids
Azathioprine
Continue all medications in peri-op period
In severe cases, may need plasma exchange or IVIG to obtain short term remission
How does pyridostigmine convert to neostigmine?
oral pyridostigmine 30mg
= IV neostigmine 1mg
In MG, how are the effects of muscle relaxants changed?
resistance to sux, ED95 is 2.6x normal, suggest dose 1.5mg / kg
- Plasma exchange may reduce ache levels and prolong sux action
Sensitive to non-depolarisers
- Avoid if possible. Start with 10% of dose
- Short acting agents only
Monitor at all time
Avoid neostigmine for risk of cholinergic crisis
Criteria to predict ICU requirement for post-op ventilation in MG?
Pre-op vital capacity < 2.9L
Chronic respiratory disease related to MG
Disease > 6 years
Dose requirement of pyridostigmine > 750mg/day
Major body cavity surgery
What is the recommended minimum anti-platelet period for a BMS
4-6 weeks of DAPT - the period of time where endothelialisation is unlikely to have occurred and the risk of in-stent thrombosis is high
In practice, DAPT often continued for 3 months
Pre-op considerations for interventional cardiology procedures (info you need from cardiologist)
- SNS driven arrhythmia? like SVT. Influences choice of anaesthesia, as ablation may be more successful under sedation (GA suppresses arrhythmia)
- Anatomical complexity, ie. congenital heart disease - influences duration of procedure.
- Need for transseptal puncture -> need GA
- Diagnostic or therapeutic?
- Need for heparin and ACT monitoring and ACT targets
- Cardiovert / defibrillation externally required?
- Expected duration of procedure - ?IDC
Intra-op considerations for interventional cardiac procedures
Remote location, radiation exposure
Long procedure - padding of pressure area, temperature management.
Position - arms wrapped in case defibrillation required during procedure.
- Particular care to prevent brachial plexus injury as arms above head
Heparinisation for transseptal puncture
Absolute immobility
High RR, low TV to decrease chest excursion
Complications of EVAR
endoleak
femoral aneurysm
Implantation syndrome
Renal injury
Spinal ischaemia
Intra-op AAA rupture
What is post-implantation syndrome post EVAR
flu like symptoms (fever, malaise) in the first few days, not associated with infection.
Due to inflammatory response to the graft.
Triad of Parkinson’s disease symptoms?
tremor, rigidity, bradykinesia
Effects of Parkinson’s Disease on anaesthesia
Increased aspiration risk
Fixed flexion deformity of the neck - difficult airway
Respiratory muscle function affected by rigidity and bradykinesia, restrictive lung disease possible.
Autonomic instability is common
Dopamine effect - tachycardia and increased myocardial contractility
Which Parkinson’s medication can have anaesthetic implications?
Selegeline (MAO-B inhibitor)
- Can precipitate serotonin syndrome
- Monoamine increased sensitivity
how and why does diastolic dysfunction occur
Impaired filling due to reduce compliance.
Risk factors include age, diabetes, renal impairment, hypertension, CAD, LVH.
Clinical symptoms of diastolic heart failure?
Signs and symptoms of heart failure with a normal LV ejection fracture.
TOE findings of diastolic dysfunction?
Evidence of LVH
Alteration of transmittal E:A valve velocities, usually E>A.
Reversal of pulmonary venous flow during atrial contraction
Reduction in mitral annular tissue velocity
Alteration in isovolumetric relaxation time
in caudal block, where the sacral hiatus in relation to the other sacral structure?
At the apex of the equilateral triangle with the base formed by a line joining the PSIS
Sacral cornua either side, just Ove the apex.
Hiatus is covered the sacrococcygeal membrane.
Contents of caudal space?
Epidural fat, nerve roots, vein
Spinal cord terminates at L3/4 in young children - filma terminale is the extension.
Dural sac terminates at S3/4
What’s the concern for performing neuraxial procedures on patients with multiple sclerosis?
Demyelinated axons may be more sensitive to toxicity from local anaesthetics.
Diagnosis of heparin resistance?
ACT fails to reach >450s after a dose of 500U/kg.
Usually caused by ATIII deficiency
Management of heparin resistance?
ATIII replacement with FFP or ATIII concentration. Precise dosing is difficult
