Other Flashcards
Pt has a pulmonary arteriovenous malformation (PAVM) - it is 3mm in size. What treatment is required?
Consideration of embolisation (no size limit - any visible on radiology should be referred)
Prophylactic abx recommended for dental/endoscopic/surgical procedures due to risk of brain abscesses
Venesection only if features of hyperviscosity
LTOT only in symptoms (often hypoxiaemic due to shunting)
Nb. pt often asymptomatic.
High risk of paradoxical stroke or MI
Pregnancy dangerous
PAVM 0.04% prevalence
Paradoxical embolus (embolus into arterial circulation) - stroke, MI, brain/peripheral abscess, discitis, migraine, frequent nosebleeds
HHT mutation e.g ENG (autosomal dominant)
- Fe def anaemia, frequent nosebleed, VTE risk
What nerves are sensory supply to the mediastinal pleura?
Phrenic nerve
How does Midazolam work? What is it’s antidote? And how much can you give? Initial and max dose
Increases GABA activity
Flumazenil = antidote
Initial dose: 2-2.5mg (0.5-1if frail/elderly)
Max dose: 7mg (3.5mg if frail/elderly)
Nb.onset approx 2min, max onset 5-10min, duration 30-120min
Pt has INR of 1.6. Is it okay to go ahead with thoracentesis (pleural aspiration)?
No absolute contraindication however would suggest correct INR to <1.5 if not urgent procedure
What is dosing of fentanyl for bronch?
Initial 25mic to max of 50
Onset almost immediate. Half life 2-7hr
What kind of doses of lidocaine might cause toxicity?
≥9.6mg/kg
What is the approx radiation dose equivalent of a CTPA?
1.3 years background
Nb. XR 5 days
VQ 7 months
Nb2. VQ gives less radiation to breast tissue but more to baby
What is atopy?
Tendency to produce IgE against innocuous antigens
How is IgE produced?
By B-cells driven by IL-4
What drives allergic inflammation?
Th2 cells + Th2 innate lymphoid cells
IL4/13/5/33/24/RSLP
What is the pathway in acute allergy?
IgE –> Mast cell degranulation–> Histamine –> H1 receptor
What is the pathway in chronic allergy?
Allergen –> Th2 –> B cells (then degranulate mast cells) + eosinophils
What classifies as anaphylaxis?
Compromise of A OR B OR C
nb. 10-20% have no skin involvement
nb2. 30% have no identifiable trigger
What is treatment for anaphylaxis?
IM adrenaline 1:1000 0.5ml adult +/- rpt
NOT steroids and anti-histamines
i.e. 0.5mg (1:1000 = 1g:1000ml)
cardiac arrest = 1ml of 1:10000 i.e. 0.1mg
What tests can be done to confirm anaphylaxis?
Tryptase
- ASAP + 1-2hrs (<4hrs) + 24hrs
- Relevant level ≥ 1.2xbaseline +2
Nb. not a rule out test
What is diagnosis of rhinitis?
2 of: running/blocked/sneezing/itching >1hr day
> 12 weeks = chronic
+ nasal polyps: think Churg Strauss
- nasal polyps: think Ab-def
Nb. unilateral symptoms, absent smell, facial pain, nose bleeds, unpleasant smell, ear symptoms are NOT TYPICAL
What is type 4 allergy?
T-cell mediated (occurs over days)
Get skin reactions - most common for drugs or contact hypersensitivity
What is type 3 allergy?
Immune complex mediated (hours-days)
Get rash, arthraliga, fever, myalgia, kidney impairment
What is type 2 allergy?
IgG mediated (hours-days)
Get cytopaenia + haemolytic anaemia
What is type 1 allergy?
IgE-mediated (<1hr)
Get anaphylaxis, rhinitis, itch, erythema, urticaria, angioedema, bronchospasm
How do you treat rhinitis?
Nasal steroid +/- nasal antihistamine (dymista = combined)
Consider immunotherapy
Nb. this is for allergy rhinitis (80% of cases)
What is considered a positive skin prick or serum IgE?
Skin: >3mm (beware cross-reactivity)
Serum: >0.35KU/L
Nb. good negative predictive value but poor positive predictive value
Is anaphylaxis always caused by IgE?
No - can be aspirin/NSAIDs, exercise, radiological contrast
When should Epipen be given for analyphylaxis?
If admitted to hospital with anaphylaxis
or known risk
What can cause isolated angioedema?
ACE-i use - remember can happen many years after starting
What are causes of non-allergic rhinitis?
Hormones, medications, irritants, NARES (ass with eosinphils –> responds to steroids)
What is treatment for allergy?
Allergen avoidance
Desensitisation - only temporary tolerance due to recent/ongoing exposure. Therefore might do to aspirin/NSAIDs/penicilln/peanut/chemo
Tolerance - persistant tolerance
–> allergen immunotherapy
- gradually increase exposures to allergy
- indications: bad rhinitis +/- mild asthma OR systemic reaction to wasp/bee
- need to known allergen, inadequate/intolerant to drugs
- CANT do if mod/severe/uncontrolled asthma or multiple allergies/pregnancy/autoimmune disease
How might OHS and OSA look different on sleep study?
OHS w/o OSA –> don’t get repetitive drop in SATS, get prolonged low SATS during REM sleep with slow return to baseline
What might you see on chest/abdomen movement and nasal flow with OSA?
Rib cage and abdomen should move together but not getting nasal flow
What is treatment for central sleep apnoea?
Autoset CPAP
BUT IF EF<45% then fixed level CPAP as autoset increases mortality
Nb. do MRI brain in central sleep apnoea to look for brainstem or cerebellapontine angle tumours
When should COPD pt be referred for pulmonary rehab?
<4 weeks hospital admission for COPD
COPD + exercise limitation due to SOB
What are causes of anterior mediastinal mass?
Anterior also called pre-vascular compartment
Thymoma
- smooth border, soft tissue attenuation
- may have cystic component +/- calcium
- metastasizes to pleura = may get plerual effusion
- usually >50, ass with hypogammaglobulinaemia
Teratoma - multiple densities visible
- soft tissue attenuation with fat within
- ring calcification, solid enhancing septa
- may have fluid inside
Thyroid mass lesion
- Contiguous with neck
Lymphoma (Hodgkin & large B cell)
- Multiple lesions
- Unilateral pleural/pericardial effusion
What does anterior mediastinal mass look like on CXR?
Obtuse angle with mediastinum
Loss of R heart border
Hilar vessels visible through
Will not be visible above clavicle
What are borders on CT for anterior mediastinum?
Sternum (know mediastinal window)
Axial: draw line around anterior pericardium/ascending aorta/aortic arch - infront = anterior (nb. lateral border = parietal pleura)
Lateral: anterior to trachea or posterior to IVC
What is treatment for periodic limb movement disorder?
Ropinorole (non-ergot dopamine agonist) +/- clonazepam (if concurrent insomonia but not routine)
- repetitive movements (usually legs) mainly in REM >15/hr + sleep disturbance
- idiopathic or ass with restless legs, OSA, REM sleep behaviour disorder, narcolepsy, CCF, HTN, ESRF, Parkinson etc
Disease+ Disease-
Test + A B
Test - C D
How calculate sens, spec, NPV, PPV?
Sens = A/(A+C)
Spec = D/(B+D)
PPV = A/(A+B)
NPV = D/(D+C)
What test compares means from two independent groups?
Unpaired t-test
If small sample (n<30) then non-parametric test Mann-Whitney U
Categorical data in contingency tables: Chi squared or Fischer exact
Nb. paired t-test = compare repeat measurement from same individual
Pt with heart disease has slate grey discolouration of skin. What is most likely medication causing this and what is the pathophysiology?
Amiodarone - photosensitivity leading to blue-grey discolouration
Foamy macrophage highly characteristic
When should oxygen be given in bronchoscopy?
> 4% change or <90% for >1min
What are clotting/anticoag requirements for bronchoscopy?
Plt count
Clopidogrel
Warfarin
DOAC
Plt >20
Clopidogrel 7d (nb aspirin can continue) - liaise with cardiologist if >12months after insertion of drug eluding stent or >1 after bare metal stent
Warfarin
- high risk (metallic mitral valve, prosthetic heart valve + AF, AF + mitral stenosis, <3months after VTE, thrombophilia syndrome) = stop five days before, start LMWH two days after stopping, but omit on day of procedure, restart warfarin on evening of procedure and continue LMWH until INR adequate
- Low risk (metal aortic valve, xenograft, heart valve, AF without valve disease,> three months after VTE) = stop warfarin, five days before, check INR, less than 1.5, restart on an evening of procedure, check iron or one week later.
DOAC not in guideline
Patient needs bronchoscopy, had MI 4 weeks ago. What should you do?
Ideally wait 4 weeks. If needed consider consult with cardiologist.
What is reversal dose for Midazolam?
Flumezanil 200 micro grams IV over 15mins
What is the risk of bleed in bronchoscopy?
Severe: 0.26%
Minor: 0.19%
Doubles if taking transbronchial biopsy
By how much is cardiovascular risk increased in pt with untreated OSA?
2-3 fold
