Pulmonary embolism: High Risk Factors and Management

 Pulmonary Embolism

Overview

• Pulmonary embolism(PE) occurs when a substance( solid,  gaseous, or liquid ) enters venous circulation and forms a blockage in the pulmonary vasculature.
• Emboli originating from deep-vein thrombosis (DVT)  are most common cause. Tumours,  bone marrow, amniotic fluid, and foreign matter also can become emboli. 
• Increased hypoxia to pulmonary tissue and impaired blood flow can result from a large embolus. A PE is a medical emergency. 
• Prevention, rapid recognition, and treatment of a PE are essential for a positive outcome. 

Health promotion and disease prevention 

• Promote smoking cessation. 
• Encourage maintenance of appropriate weight for height and body frame. 
• Encourage a healthy diet and physical activity. 
• Prevent deep-vein thrombosis (DVT) by encouraging clients to do leg exercise, wear compression stockings, and avoid sitting for long periods of time. 

Assessment 

• Risk factors 
• Long-term immobility 
• Oral contraceptive use and estrogen therapy 
• Pregnancy 
• Tobacco use
• Hypercoagulability ( elevated platelet count)
• Obesity 
• Surgery ( especially orthopaedic surgery of the lower extremities or pelvis )
• Heart failure or chronic atrial fibrillation 
• Autoimmune hemolytic anaemia 
• Long bone fracture 
• Advanced age

Subjective data

• Anxiety 
• Feeling of impending doom
• Pressure in chest
• Pain upon inspiration and chest wall tenderness 
• Dyspnea and air hunger 

Objective data

• Physical assessment findings 
• Pleurisy
• Pleural friction rub
• Tachycardia 
• Hypotension 
• Tachycardia 
• Adventitious breath sounds(crackles) and cough
• Heart murmur in S3 and S4
• Diaphoresis 
• Low-grade fever
• Decreased oxygen saturation level,  low Spo2, cyanosis
• Petechiae ( red dots under the skin) over chest and axillae. 
• Pleural effusion 
• Laboratory test 
• ABG analysis 
• PaCO2 levels are low due to initial hyperventilation. 
• As hypoxaemia progresses, respiratory acidosis occurs
• CBC analysis to monitor haemoglobin and hematocrit 
• D- dimer
• Elevated above expected reference range in response to clot formation and release of fibrin degradation products 

Diagnostic procedures 

• Chest X-ray and computed tomography (CT) scan
• These provide initial identification of a PE. A CT scan most commonly used. A chest X-ray can show a large PE
• Ventilation- perfusion (V/Q) scan
• Images show the circulation of air and blood in the lungs and can detect a PE
• Pulmonary angiography 
• This is the most thorough test to detect a PE,  but it is invasive and costly. A catheter is inserted into the vena cava to visually see a PE
• Pulmonary angiography is a higher risk procedure than a V/Q scan

Patient-centred care

Nursing care

• Administer oxygen therapy as prescribed to relieve hypoxaemia and dyspnea. 
• Position client to maximize ventilation (high-Fowler's 90%)
• Initiate and maintain IV access 
• Administrator medication as prescribed 
• Provide emotional support and comfort to control client anxiety 
• Monitor changes in level of consciousness and mental status 

Medications 

• Anticoagulants: enoxaparin (Lovenox), heparin, warfarin 
• Anticoagulants ate used to prevent clots from getting larger or additional clots from forming.
• Nursing considerations 
• Assess for contraindications (active bleeding, peptic ulcer disease, history of stroke, recent trauma )
• Monitor bleeding time- prothrombin time (PT) and international normalized ratio (INR) for warfarin, partial thromboplastin time (aPTT) for heparin, and complete blood count (CBC)
• Monitor for side effects of anticoagulant ( e.g. thrombocytopenia, anaemia, haemorrhage)

• Thrombolytic therapy- alteplase (activase) and streptokinase
• Used to dissolve blood clots and restore pulmonary blood flow
• Similar side effects and contraindications as anticoagulants 
• Surgical intervention 
• Embolectomy: surgical removal of embolus 
• Vena cava filter: Insertion of a filter in the vena cava to prevent further emboli from reaching the pulmonary vasculature

Complications 

• Decreased cardiac output - blood volume is decreased 
• Monitor for hypotension, tachycardia, cyanosis, jugular venous distension, and syncope 
• Assess for the presence of  S3 and S4 heart sounds
• Initiate and maintain IV access 
• Monitor urinary output
• Administer IV fluids to replace vascular volume 
• Continuously monitor the ECG
• Administer inotropic agents ( milrinone, dobutamine, to increase myocardial contractility 
• Vasodilators may be needed if pulmonary artery pressure is high enough that it interferes with cardiac contractility 
• Hemorrhage  - Risk for bleeding increase due to anticoagulant therapy 
• Assess for oozing, bleeding or bruising from injection and surgical sites.
• Monitor cardiovascular status 
• Monitor CBC and bleeding times
• Administer IV fluids and blood products as required 
• Monitor internal bleeding ( measure abdominal girth and abdominal or flank pain)