Unit 12 Week 2 Flashcards
Risk factors for fracture
- being female (smaller and lose density quicker)
- old age
- smoking
- alcohol
- steroids
- rheumatoid arthritis
- Diabetes
- previous fracture
- family history
- higher BMI
How does a blood clot contribute to right ventricular strain
- dislodged emboli gets into pulmonary circulation and occludes pulmonary vasculature
- PE = abrupt vascular occlusion
- increase to pulmonary artery pressure
- pressure in RV increases causing muscle stretch, increased wall tension, elevated HR and increased oxygen demand due to lack of coronary perfusion
- Mechanical stretch and ischaemia provokes a cytokine and immune mediated inflammatory response, converting RV muscle to proinflam phenotype
ECG sign of myocardial ischaemia
inverted T waves viewed from lead 3
What is an embolus?
detached intravascular solid, liquid or gasous mass that is carried to a distant site of origin
Majoirty derive from thrombus
Difference between thrombus and embolus
Thrombus is a clot that develops in a vessel and stays, embolus gets lodged distally
What is a thromboembolus?
blood clot that has broken off and become lodged in and obstructs the pulmonary arterial system leading to severe respiratory dysfunction
What is a saddle pulmonary embolism
large pulmonary embolism that straddles the bifurcation of the pulmonary trunk, extending into the left and right pulmonary arteries
If large enough it can cause right sided heart failure
Signs of right sided heart failure
Dilated right ventricle, leftward bulge of the interventricular septum and enlargement of the pulmonary trunk
Causes / types of pulmonary embolism
- Thrombosis via venous system accounts for majority of cases
- Fat- following long bone fracture or orthopaedic surgery (e.g. femur)
- Amniotic fluid- during labour if the placental membranes break at the same time as uterine veins
- Air- following neck vein cannulation
- Foreign bodies
- Tumour cells
Major risk factors for venous thromboembolism
- Surgery
- Obstetrics
- Lower limb issues (fractures and varicose veins)
- Malignancy
- Reduced mobility
- Previous proven –VTE
- Major trauma
- Spinal cord injury
- Central venous lines
Minor risk factors for venous thromboembolism
- Cardiovascular (hypertension, stroke, heart disease and failure)
- Osterogens (combined oral contraceptive, hormone replacement therapy)
- Haematological (thrombotic disorders)
- Renal (nephrotic syndrome etc)
- COPD
- Neurological disability
- Occult malignancy
- long distance sedentary travel
- obesity
- other chronic disaeses (IBD)
Pathophysiology thromboembolism disease
Fragment of thrombus is broken off and carried through progressively larger veins and R side of heart before entering pulmonary vasculature
-Occlusion of blood vessels, decreased gas exchange, hypoxia, damages organs ,potentially to the point of death
Often multiple embolisms at once so tend to occur close together timewise
Fat embolism pathophysiology
Micro-emboli of fat + RBC aggregates can cause occlusion
Fatty acids can also damage endothelium leading to increased platelet activation and granulocyte recruitment
Air embolism pathophysiology
commonly due to clinical procedure (e.g. laparoscopic surgery)
Due to negative pressure in blood vessels pulling in air
Air in vessel can cause intense inflam response
Symptoms of PE
- Acute dypnea
- Pleuritic chest pain
- Anxiety
- Dizziness, light headedness or fainting
- Heart palpitations or irregular heart beat
- Coughing (sometimes w blood)
- Sweating
- low blood pressure and associated symptoms
Associated w symptoms of Deep vein thrombosis so also: reddening, warming or swelling of the legs
