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32 Cards in this Set
- Front
- Back
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Embolism |
It is a detached intravascular solid, liquid or gaseous mass that is transported in the blood from the site of origin to another site. |
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Solid emboli |
oboemboli Atheromatous material Tumour emboli ThromoboemboliAtheromatous materialTumour emboliTissue fragmentsBacterial clumpsParasitesForeign bodies Tissue fragments Bacterial clumps Parasites Foreign bodies |
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Liquid emboli |
Fat Bone marrow Amniotic fluid |
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Gaseous emboli |
Air Other gases |
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Classify based on infected or not |
Bland/sterile and septic |
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Classify based on the source |
Endogenous and exogenous |
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Cardiac emboli |
Arise from the left side of the heart. From, atrial appendage, left ventricle in MI, vegetations on the valves in infective endocarditis |
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Vascular emboli |
Arterial emboli - Atheromatous plaque, aneurysm Venous emboli - DVT, tumour emboli Lymphatic emboli - tumour emboli |
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Classify based on the flow of emboli |
Paradoxically and retrograde emboli |
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Paradoxical emboli |
Emboli originates in the venous circulation and bypass the lungs by travelling through a right-to-left shunt like ASD or interventricular defect. They enter the left side of the heart and block the blood flow to systemic arteries |
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Retrograde emboli |
They travel against the flow of blood. Ex. Prostatic carcinoma metastasis to the spine. It occurs through retrograde spread via the intraspinal veins which carry the emboli from large thoracic ducts and abdominal veins due to increased pressure in the body cavities. |
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Pulmonary embolism |
An embolism in which the emboli occludes pulmonary arterial tree. |
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Site of origin of emboli |
Deep leg veins - popliteal, femoral, iliac Pelvic veins Vena cava |
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Risk factor |
Surgery Advancing age Obesity Prolonged operative procedure Postoperative infection Cancer Pre-existing venous disease |
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Mechanism |
DVT undergoes fragmentation ! The thromboemboli are carried through larger vascular channels ! Right side of the heart ! Right ventricle ! Enter pulmonary arterial vasculature |
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Fate of pulmonary embolism |
Resolution or organisation Massive pulmonary embolism Multiple recurrent pulmonary emboli Paradoxical emboli |
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Saddle embolism |
A large pulmonary embolus lodging at the bifurcation of main pulmonary artery. Produces acute massive obstruction to the blood flow to both lungs. Effects; Acute right ventricular failure Shock: Right ventricular failure ! Reduction in left ventricular cardiac output ! Sudden severe hypotension ! May result in sudden death |
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Consequences |
Pulmonary infarction Pulmonary haemorrhage Pulmonary hypertension Minimal effect |
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Pulmonary infarction |
An embolus can produce infarction in the patients with CCF or chronic lung disease.
Type - hemorrhagic type - blood supply to infarcted area by bronchial artery Shape - pyramidal Fate - granulation tissue grows from the edges of the infarct and results in organisation of infarct and forms a fibrous scar.
Clinical features Cough Stabbing pleuritic pain Shortness of breath Hemoptysis Pleural effusion with the pleural fluid being blood stained. |
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Pulmonary hypertension |
Multiple recurrent pulmonary emboli ! Mechanical blockage of arterial bed ! Pulmonary hypertension ! Right ventricular failure. |
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Systemic thromboembolism |
The emboli which occlude systemic arterial circulation Produce infarcts in the region supplied by the involved vessel. |
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Sources |
Heart: Intracardiac mural thrombi - MI of left ventricular wall, mitral stenosis, dilatation of left atrium, atrium fibrillation. Paradoxical emboli Valvular source - bacterial endocarditis and prosthetic valves. Blood vessels - on ulcerated atherosclerotic plaques or from aortic aneurysms Unknown origin |
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Consequences |
Arterial emboli travel, venous emboli lodge in a vascular bed - lung. Arterial emboli pass through narrow arterial lumen and lodge at points where the lumen narrows abruptly - bifurcation or in the area of an atherosclerotic plaque. Fate Propagation and obstruction Fragmentation and lysis |
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Major sites affected by arterial thromoboemboli |
Lower extremity - gangrene Brain - ischemic necrosis Intestine - emboli in mesenteric vessels - infarction of the bowel Kidney - renal artery embolism - peripheral infarcts Blood vessels - emboli originating from bacterial vegetation - inflammation of arteries and mycotic aneurysm Other sites - sleep and upper extremities |
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Fat and marrow embolism |
Consists of microscopic globules of fat with or without bone marrow. |
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Causes |
Trauma to adipose tissue with fracture Soft tissue trauma and burns Vigorous cardiopulmonary resuscitation |
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Manifestations |
Usually asymptomatic Fat embolism syndrome |
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Consequences |
Sites of arrest of fat emboli - Venous - lodged in the lungs. Systemic circulation - arrested in brain, kidney, etc., Autopsy findings Lung - acute respiratory distress syndrome. Brain - cerebral edema, small hemorrhages and microinfarcts. |
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Clinical presentation |
Time - 1 to 3 days after trauma Respiratory symptoms - sudden onset of tachypnea, dyspnoea, tachycardia - lead to respiratory failure. Neurologic symptoms - Irritability, restlessness, delirium, coma Rapid onset of thrombocytopenia with diffuse petechial rash - diagnostic feature Anemia Chest radiography shows diffuse opacity of lungs - progress to opacification if lungs - characteristic of acute respiratory distress syndrome. |
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Air embolism - causes |
Trauma - neck wounds and chest wall injury. Surgical procedures - thoracocentesis, punctures of the great veins during obstetric or laparoscopic surgery, in coronary artery during bypass surgery, hemodialysis. |
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Amount of air required |
More than 100cc |
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Mechanism |
In circulation, air bubbles coalesce to form frothy masses that obstruct blood flow in the right side of the heart |
