DVT & pulmonary embolism Flashcards
what is deep vein thrombosis?
= thrombus (clot) formation within the lumen in the deep venous circulation (usually legs) but can be anywhere
what is a PE?
= thrombus (clot) that has embolised (travelled) & lodged in the pulmonary circulation
what is venous thromboembolic disease (VTE)?
= clot formation within the venous circulation
- covers both DVT and PE
what are the 2 types of DVT?
and what location are they referring to?
1) DISAL vein thrombosis
= refers to DVT of the calves
2) PROXIMAL vein thrombosis
= refers to DVT of popliteal vein or femoral vein
- termed proximal as they are closer to the heart.
what are the 3 things that make up the Virchow’s triad in DVT’s and PE?
1) endothelial injury
2) hyper-coagulable state
3) circulatory stasis
what makes up hyper-coagulable state? (abnormally increased state of blood clotting)
- malignancy
- pregnancy & permpartum period
- oestrogen therapy
- inflammation bowel disease
- sepsis
- thrombophilia
what makes up endothelial injury?
- venous disorders
- venous vacilar damage
- trauma or surgery
- indwelling catheters
what makes up circulatory stasis?
- left ventricular dysfunction
- immobility or paralysis
- venous insufficiency or varicose veins
- venous obstruction from tumour, obesity or pregnancy
what are exposing risk factors for VTE?
- surgery
- trauma
- acute medical illness
- acute heart failure
- acute respiratory failure
- ventral venous catheterisation
what are pre-disposing (patient characteristics) risk factors?
- history of VTE
- chronic heart failure
- advanced age
- varicose veins
- obesity
- immobility or paresis
- pregnancy
- renal insufficiency
- hormone therapies
what are just normal risk factors?
- smokinng
- travel (long haul)
- oral contraceptive pill
- hormone replacement
- protein C or S deficiency
- pregnancy
- day or major surgery
- active malignancy
- prothrombin gene mutation
how does DVT present?
- painful
- swollen limb with redness & heat
- tenderness along vein
- sub-acute development
- no other obvious cause
how does PE present?
- sudden shortness of breath
- pleuritic pain
+/- - collapse
+/- - haemopytsis
- hypoxia
- tachycardia
- BP may be low
what score can be used to test the probability of having a DVT/PE?
WELLS score
3 = clinical signs & symptoms compatible with DVT
3 = PE judged to be most likely diagnosis
1.5 = surgery or bedridden for more than 3 days during past 4 weeks
1.5 = previous DVT or PE
1.5 = heart rate > 100 min
1 = haemoptysis
1 = active cancer
< 4 = low
4.5-6 = moderate
> 6 = high
what isD-dimer?
a breakdown of product of cross linked fibrin
what value show their at risk for VT?
High negative predictive value (<98%) for VTE
Low positive predictive value for VTE
what should you do if DVT is likely or low risk of PE?
then check D-dimer
if D-dimer is high, what should you do?
a scan
if D-dimer is normal what can be excluded?
VTE can be excluded
how can you determine how and a PE is?
PE = PESI score + patient characteristics
PESI = PE SEVERITY INDEX
- as PE causes right strain & pressure can be risk of deterioration and death
when can post thrombotic syndrome occur?
usually within 5 years after idiopathic DVT
what is post- thrombotic syndrome characterised by?
- pain
- oedema
- hyperpigmentation
- eczema
- varicose collaterali veins
- venous ulceration
what things are included in the PESI score?
- age
- male sex
- cancer
- chronic heart failure
- chronic pulmonary disease
- pulse rate > 110BPM
- systolic BP < 100mmHg
- respiratory rate > 30BPM
- temperature < 36
- altered mental status
- arterial oxyhemoglobin saturation < 90%
how do you manage a DVT?
= oral anti-coagulation
- a small subset of patients where THROMBOLYSIS can be considered
how do you manage a PE?
= thrombolysis then oral anti-coagulants
- intermediate or low risk = oral anti-coagulation
what is thrombolysis the same as?
= fibrinolysis
what does thrombolysis do?
aggressive clot destruction
specifically, what type of PE should thrombolysis treat?
= massive PE
what are the 3 anti-coagulants that could be used?
1) direct oral anti-coagulants
2) vitamins K antagnoists
3) low molecular weight heparin injections
what are 2 examples of direct oral anti-coagulants?
1) apixaban
2) rivaroxaban
what is an example of a Vit K antagonists?
= warfarin
in what types of patients is low molecular weight heparin injections still used?
= active cancer
= PE
in provoked VTE with reversible factors, how long should you be given treatment for?
3-6months
in provoked VTE with IRReversible factors, how long should you be given treatment for?
= 3-6months or lifelong depending on patient factors
in men with unprovoked events, what would you advise?
= long term anti-coagulation unless bleeding tissue
in women with unprovoked events, what would you advise?
= HERDOO-2 score and advise by that
