Pulmonary Embolism Part 1 Flashcards
— refers to the obstruction of the —– or one of its branches by a —- (or thrombi) that originate(s) somewhere in the — or in the —.
Pulmonary embolism (PE), pulmonary artery, thrombus, venous system, right side of the heart
Most commonly, PE is due to a
dislodged or fragmented DVT
other types of emboli that may be implicated:
air, fat, amniotic fluid, and septic
PE is describe as an —- of the outflow tract of the main pulmonary artery or of the — of the pulmonary arteries
occlusion
bifurcation
Multiple small emboli can lodge in the terminal pulmonary arterioles, producing
multiple small infarctions of the lungs
pulmonary infarction causes — of part of the lung
Ischemic necrosis
When a thrombus completely or partially obstructs a pulmonary artery or its branches, the
alveolar dead space is increased
a reaction that compounds the ventilation–perfusion (V./Q.) imbalance that ensues.
increase in pulmonary vascular resistance
hemodynamic consequences
increased pulmonary vascular
resistance
The hemodynamic consequences are increased pulmonary vascular resistance due to the
regional vasoconstriction and reduced size of the pulmonary vascular bed.
When the work requirements of the right ventricle exceed its capacity, right ventricular failure occurs, leading to a
decrease in cardiac output
decrease in systemic blood pressure
development of shock
Clinical manifestations
depend on the size of the thrombus and the area of the pulmonary artery occluded by the thrombus.
*Nonspecific
*Dyspnea
*Chest pain
*anxiety
*fever
*tachycardia
*apprehension
*cough
*diaphoresis
*hemoptysis
*syncope
*Tachypnea
Obstruction of the pulmonary artery can result
pronounced dyspnea
sudden substernal pain
rapid and weak pulse
shock
syncope
sudden death
is the most frequent symptom; the duration and intensity of the — depend on the extent of embolization.
Dyspnea
is common and is usually sudden and pleuritic in origin; however, it may be substernal and may mimic angina
Chest pain
The most frequent sign is
Tachypnea
In many instances, PE causes few signs and symptoms, whereas in other instances, it mimics various other
cardiopulmonary disorders
Assessment and Diagnostic Findings
Initial:
*Chest x-ray
*ECG
*Pulse oximetry
*ABG analysis
*D-dimer assay
*MDCTA/pulmonary arteriogram/V./Q. scan
is usually normal but may show infiltrates, atelectasis, elevation of the diaphragm on the affected side, or a pleural effusion. It is most helpful in excluding other possible causes.
Chest x-ray
most frequent ECG abnormality is
Sinus tachycardia
nonspecific ST-T wave abnormalities