RESPIRATORY

ResponseHAD CLOTS
Hormones (Exogenous Oestrogen)
Age >= 50
DVT/PE history
Coughing blood (Haemoptysis)
Leg swelling - unilateral
O2 <95% (RA sats)
Tachycardia >=100
Surgery

False negative = 3%

ResponseMust be used with scoring system - can only use if pretest probability is low - WELLS Score

ResponseSmall clot load (eg: Below knee DVT)
Mature thrombus
Defective native fibrinolysis (Which also can contribute to thrombus formation initially)
Immediately post injury (ie: no time for D dimer to form)

ResponsePro:
Widely available, quick,
Excludes some other pathologic causes for symptoms
Gives some information about complications (RV strain, pulmonary infarct)

Cons
Risk of contrast nephropathy
Contrast allergy
Deterioration in CT scanner

Radiation exposure not that relevant if old, young female of reproductive age/pregant = bad

Positive scan = filling deficits in major pulmonary vessels

ResponseBilateral proximal pulmonary emboli
Dilated pulmonary trunk
RV>LV
LV septum flattened.

ResponseSaddle embolus
R atrial dilation

Bilateral consolidation/collapse not specific for PE so not accepted (Question didn’t specify specific to PE but also it was about diagnosing a PE in a pregnancy lady so i guess thats fair)

ResponsePro: lower radiation dose (Especially with perfusion only scan), similar sensitivity to CTPA for mod-large PE. Compare with previous VQ scans. Identifies large perfusion deficit
Con: Delay in obtaining scan, interpretation difficult in old lungs - indeterminate result, false positive in existing lung disease, Doesn’t diagnose alternate pathology

Positive scan = unmatched perfusion defects

ResponseOK for picking big PE’s in major vessels, may be an option for pregnant women if stable

ResponseNo radiation, useful in patients with contraindication to radiation,
Not diagnostic of PE

ResponseRight ventricular strain pattern - Simultaneous T wave inversion in the inferior (II, III, aVF) and right precordial leads (V1-V4) is the most specific finding (99% in one study. Associated with hith pulmonary artery pressures.
Sinus tachy - most commonly seen (44%)
RBBB (Complete or incomplete, ~18%)
Right axis deviation (~16%) (Ironically can also have LAD)
Dominant R wave in V1
R atrial enlargement - “P pulmonale” - peaked P waves in lead II>2.5mm
S1Q3T3 - Deep S in I, Q in III, TWI in III. not sensitive, nor specific, ~20% of PE’s. (Classic finding though)
Atrial arrhythmia
Non specific ST-T wave changes
Clockwise rotation
NSYD 2019.2-9 for more detail. This was summarised

ResponsePro: Bedside test - provisional Dx in shocked pt who can’t go to scanner, R heart strain assessed, no radiation
Con: Operator dependent, less helpful in segmental/small PE. rarely provides direct evidence of clot

ResponseRV strain:

• Dilated RV (larger than LV)
• septal flattening (D Sign)
• Poorly contractile RV
• Reduced TAPSE <1.6cm
• High RV pressures, high pulmonary arterial pressures
• RA enlargement
• Tricuspid regurgiation
• McConnell sign Echocardiographic pattern of RV dysfunction consisting of akinesia of the mid free wall but normal motion at the apex - 77% sensitivity and 94% specificity for diagnosis of pulmonary embolism - LIFTL Jun 24

Thrombus in RA/RV
Hyperdynamic LV
Dilated IVC with lack of respiratory collapse

ResponseWestermarks sign, hamptons hump, pulmonary infarct

ResponseProthrombotic screeen - identify underlying cause
Troponin - Prognostic significance
Platelets (if starting heparin)
US legs - identify clot burdon

ResponseImprove oxygenation: HFNP 50L titrated to sats of 92-96%
Vasopressors - noradrenaline target BP 90-100
Systemic thrombolysis with dose

ResponseAlteplase

• Stable - alteplase 100 mg - 10 mg bolus then 90 mg over 2 hours (If >65kg)
• Deteriortating/arrests - 50 mg alteplase bolus

Tenecteplase - 40 mg (0.5mg/kg to nearest 5mg) IV bolus

ResponseIV fluid bolus aim SBP >100 >> central access and vasopressor (Norad) if poorly responsive
Bedside echo - elevated RV pressure or deviation of interventricular septum suggestive of increased RV pressure
Chase history of brain bleed/surgery
D/W Cardiothoracics suitability of surgical embolectomy
Discussion of treatment options - Thrombolysis with tenecteplase if RV pressure high vs anticoagulation if RV pressure normal
If arrests - thrombolysis

ResponseHeparin, Rivaroxaban 15 mg BD x 3 weeks then 20 mg daily

ResponseThrombolytics

• Massive PE with haemodynamic compromise, or dealy to alternate therapy
• CI - the usual contraindications for thrombolytics
• Alteplase 100 mg over 2 hours (if unstable give first 20 mg as bolus)

Thoracotomy with embolectomy

• Massive PE with haemodynamic compromise and access to cardiothoracics
• CI - no timelay access to CTx surgery

Interventional radiology with embolectomy/clot retrieval

• Access ro IR, ability to lie flat (often need to be intubated)
• CI - contrast allergy (Might have had CTPA in stem…. So not great marks) renal failure (relative), no access to IR

ResponseGenerally accepted:
Cardiac arrest - CPR will need to be prolonged
Massive PE - hypotension, Systolic < 90 for >15 mins
More controversial:
R heart strain on echo or positive cardiac enzymes (PEITHOS study)
Extensive clot burden - Moderate PE (R + L main pulmonary trunks or >2 lobes with 70% involvement - MOPPETT study)
Severe or worsening RV function “submassive PE”
Worsening despite anticoagulation
Severe hypoxia

The use of thrombolysis for massive PE is widely accepted as the standard of care. This has been shown to reduce mortality and PE recurrence compared to anticoagulation alone. The controversial bit is the use of thrombolysis for submassive PE - EM CRIT

ResponseMOPETT
PEITHOS

ResponsePros: rapidly reduce clot burden to reduce RV strain, improving haemodynamics. Reduce long term pulmonary hypertension, Mortality benefit in massive PE
Cons: ICH/other bleed, Cost

ResponseABSOLUTE (Basically anything in the skull)
Previous ICH
Structural intracranial disease
Ischaemic stroke <3 months
Recent brain/spinal surgery
Recent head trauma with fracture or brain injury
Active bleeding

ResponseTraumatic CPR <10 days
Recent bleeding - Marjor <6 months, Minor <10 days
Recent surgery <3 months, or invasive procedure
Ischaemic stroke >3 months previously
GI ulceration/varices within <3 months
Malignancy with bleeding risk
Anticoagulation prior to presentation, Bleeding disorder, low platelets
Diabetic retinopathy
Pregnancy
endocarditis/pericarditis/pericardial effusion
Pancreatitis
Age >75, body weight <60
BP>180/110

ResponseMemory aid: Name bad obs + heart/lung disease gets you most of the points
Age
Sex M>F
Hx cancer
Hx CCF
Hx Chronic lung disease
HR >110
SBP <100
RR >30
T <36
Altered mental status
O2 saturation <90%