Transcript Care of Patient With Pulmonary Embolism (PE)

Care of Patient With Pulmonary Embolism
(PE)
Dr. Belal Hijji, RN, PhD
October 29, 2011
Learning Outcomes
At the end of this lecture, students will be able to:
• Describe PE, its pathophysiological changes, and discuss its
clinical manifestations.
• Identify the diagnostic test that may be used to diagnose PE.
• Discuss the medical and nursing management of PE.
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Introduction
• Pulmonary embolism (PE) is an obstruction of the pulmonary
artery (next slide) or one of its branches by a thrombus (or
thrombi) that originates somewhere in the venous system.
• The types of emboli could be a blood clot (most common), air,
fat, amniotic, fluid, and septic (from bacterial invasion of the
thrombus).
• PE is often associated with trauma, surgery (orthopedic),
pregnancy, heart failure, age > 50 years, hypercoagulable
states, and prolonged immobility.
• Most thrombi originate in the deep veins of the legs; other sites
include the pelvic veins and the heart’s right atrium.
• An enlarged right atrium in fibrillation causes blood to
stagnate[‫ ]ركود‬and form clots that may travel into the
pulmonary circulation causing PE.
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Pathophysiology
• When there is a complete or partial obstruction of a pulmonary
artery or its branches by a thrombus, the alveolar dead space
(next slide) is increased. The area, although continuing to be
ventilated, receives little or no blood flow, resulting in
impaired or absent gas exchange.
• In addition, various substances are released from the clot and
surrounding area, causing regional blood vessels and
bronchioles to constrict. This causes an increase in pulmonary
vascular resistance. This results in an increase in pulmonary
arterial pressure and, in turn, an increase in right ventricular
work to maintain pulmonary blood flow.
• When the work requirements of the right ventricle exceed its
capacity, right ventricular failure occurs, leading to a decrease
in cardiac output followed by a decrease in systemic blood
pressure and the development of shock.
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Alveolar dead space: A well-ventilated part of the lung is not
receiving blood flow. The air reaching that region of the lung is
therefore wasted since it cannot participate in gas exchange, thus the
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alveoli are considered dead.
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Clinical Manifestations
• The symptoms of PE depend on the size of the
thrombus and the area of the pulmonary artery
occluded by the thrombus.
• Dyspnea is the most frequent symptom; while
tachypnea is the most frequent sign. Chest
pain is common and is usually sudden and
pleuritic. Other symptoms include anxiety,
fever, tachycardia, apprehension, cough,
diaphoresis, hemoptysis, and syncope.
• Deep venous thrombosis is closely associated
with the development of PE. Typically,
patients report sudden onset of pain and/or
swelling and warmth of the proximal or distal
extremity, skin discoloration, and superficial
vein distention.
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Assessment and Diagnostic Findings
• Early recognition and diagnosis of PE are priorities as death
commonly occurs within 1 hour of symptoms.
• The diagnostic workup includes a ventilation–perfusion scan,
pulmonary angiography, chest x-ray (may show infiltrates,
atelectasis, elevation of the diaphragm on the affected side, or
a pleural effusion), ECG (sinus tachycardia, PRinterval
depression, and nonspecific T-wave changes), and arterial
blood gas analysis (may show hypoxemia and hypocapnia
(from tachypnea)).
• If lung scan results are not definitive, pulmonary angiography
is the gold standard for the diagnosis of PE.
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Medical Management
• Emergency management.
– Nasal oxygen to relieve hypoxemia, respiratory distress, and
central cyanosis.
– Intravenous infusion lines to administer medications or fluids.
– A perfusion scan, arterial blood gas determinations are
performed. Pulmonary angiography may be performed.
– Hypotension is treated by a slow infusion of dobutamine
(Dobutrex).
– The ECG is monitored continuously for dysrhythmias which
may occur suddenly.
– Digitalis glycosides, intravenous diuretics, and antiarrhythmic
agents may be indicated.
– Blood is drawn for serum electrolytes and complete blood count.
– Intubation and mechanical ventilation may be performed based
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on clinical assessment and arterial blood gas analysis.
• Emergency management (Continued…).
– In case of hypotension, a Foley’s catheter is inserted to monitor
urinary output.
– Small doses of intravenous morphine to relieve the patient’s
anxiety, to alleviate chest discomfort, to improve tolerance of the
endotracheal tube, and to ease adaptation to the mechanical
ventilator.
• Pharmacologic therapy. (Anticoagulation)
– Heparin is used to prevent recurrence of emboli. The dose is an
intravenous bolus of 5,000 to 10,000 units, followed by a
continuous infusion at a rate of 18 U/kg per hour. The rate is
reduced in patients with a high risk of bleeding. Heparin is
usually administered for 5 to 7 days.
– Warfarin sodium administration is begun within 24 hours after
initiation of heparin therapy because its onset of action is 4 to 5
days. Warfarin is usually continued for 3 to 6 months.
Anticoagulation therapy is contraindicated in patients who are at
risk for bleeding (eg, those with gastrointestinal conditions or
with postoperative or postpartum bleeding).
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• Pharmacologic therapy (Continued…). Thrombolytic
therapy
– Streptokinase may be used in patients who are hypotensive and
have significant hypoxemia. It resolves the thrombi or emboli
more quickly and reduces pulmonary hypertension and
improves perfusion, oxygenation, and cardiac output.
– Is initiated after stopping heparin. During therapy, all but
essential invasive procedures are avoided because of potential
bleeding.
– Cessation necessitates the initiation of anticoagulants.
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Nursing Management
• Minimizing The Risk of Pulmonary Embolism
– A major responsibility of the nurse is to identify patients at high
risk for PE and to minimize the risk of PE in all patients.
Therefore, the nurse must give attention to conditions
predisposing to a slowing of venous return (i.e. prolonged
immobilization, prolonged periods of sitting/traveling, varicose
veins, spinal cord injury), hypercoagulability due to release of
tissue thromboplastin after injury/surgery (i.e. pancreatic, GI, GU,
breast, or lung tumor, increased platelet count in polycythemia),
venous endothelial disease (i.e. thrombophlebitis, foreign bodies
such as IV/central venous catheters)
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• Preventing Thrombus Formation. The nurse:
– encourages ambulation and active and passive leg exercises to
prevent venous stasis in patients on bed rest and to help increase
venous flow.
– discourages the patient against sitting or lying in bed for
prolonged periods, crossing the legs, and wearing constricting
clothing. Legs
– discourages legs dangling or feet placed in a dependent position
while sitting on the edge of the bed; instead, the patient’s feet
should rest on a chair.
– Should not leave intravenous catheters in place for prolonged
periods.
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• Assessing Potential For Pulmonary Embolism. The nurse
should:
– examine patients who are at risk for developing PE for a positive
Homans’ sign (pain in the calf as the foot is sharply dorsiflexed),
which may or may not indicate impending thrombosis of the leg
veins. A positive Homans’ sign may indicate DVT.
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• Monitoring Thrombolytic Therapy. The nurse:
– keeps the patient on bed rest
– assesses vital signs Q2H.
– ensures that tests to determine prothrombin time or partial
thromboplastin time are performed 3 to 4 hours after the
thrombolytic infusion is started to confirm that the fibrinolytic
systems have been activated.
– ensures that only essential venipunctures are performed because
of the prolonged clotting time, and manual pressure is applied to
any puncture site for at least 30 minutes.
– uses pulse oximetry to monitor changes in oxygenation.
– immediately discontinues the infusion if uncontrolled bleeding
occurs.
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• Managing Chest Pain. The nurse:
– Places the patient in a semi-Fowler’s position which is more
comfortable for breathing.
– continues to turn the patient frequently and repositioning him to
improve the ventilation–perfusion ratio in the lung.
– Administers opioid analgesics as prescribed for pain.
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• Managing Oxygen Therapy. The nurse:
– gives careful attention the proper use of oxygen and ensures that
the patient understands the need for continuous oxygen therapy.
– assesses the patient frequently for signs of hypoxemia and
monitors the pulse oximetry values to evaluate the effectiveness of
the oxygen therapy.
– encourages deep breathing and performs incentive spirometry to
minimize or prevent atelectasis and improve ventilation.
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• Managing Anxiety. The nurse:
– encourages the stabilized patient to talk about any fears or
concerns related to this frightening episode.
– answers the patient’s and family’s questions concisely and
accurately.
– explains the therapy, and describes how to recognize untoward
effects early.
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