Pulmonary EmbolismPulmonary Embolism
Victor Politi, M.D.,FACPVictor Politi, M.D.,FACPMedical Director SVCMC- School of Allied Medical Director SVCMC- School of Allied HealthHealth
IntroductionIntroductionThrombophlebitisThrombophlebitis - Inflammation of the - Inflammation of the
vein with the presence of a blood clot. vein with the presence of a blood clot. It can be difficult to know what came first It can be difficult to know what came first
— the clot or the inflammation ? — the clot or the inflammation ?
A blood clot is a jelly-like mass of A blood clot is a jelly-like mass of congealed blood. congealed blood.
Clotting is the normal way the body stops Clotting is the normal way the body stops bleeding and begins healing following bleeding and begins healing following injury. injury.
Once the clot has done its job, the body Once the clot has done its job, the body absorbs it. absorbs it.
Sometimes, however, blood clotting can Sometimes, however, blood clotting can prove harmful.prove harmful.
IntroductionIntroduction
IntroductionIntroductionDeep vein thrombosis (DVT) is a condition Deep vein thrombosis (DVT) is a condition
in which blood clots form in a vein deep in which blood clots form in a vein deep within the body. The word within the body. The word thrombosisthrombosis means forming a blood clot. The clot itself means forming a blood clot. The clot itself is called a is called a thrombusthrombus
Patients who have undergone gynecologic surgery, Patients who have undergone gynecologic surgery, those with major trauma, and those with indwelling those with major trauma, and those with indwelling venous catheters may have DVTs that start at any venous catheters may have DVTs that start at any location. location.
For other patients, lower extremity venous thrombosis For other patients, lower extremity venous thrombosis nearly always starts in the calf veins, which are involved nearly always starts in the calf veins, which are involved in virtually 100% of all cases of symptomatic in virtually 100% of all cases of symptomatic spontaneous lower extremity DVT. spontaneous lower extremity DVT.
Although DVT starts in the calf veins, it already has Although DVT starts in the calf veins, it already has propagated above the knee in 87% of symptomatic propagated above the knee in 87% of symptomatic patients before the diagnosis is made. patients before the diagnosis is made.
DVT usually involves the formation DVT usually involves the formation of a large clot in the deep veins of a large clot in the deep veins in the lower legs and thighs. in the lower legs and thighs.
In rare instances, DVT can occur in the In rare instances, DVT can occur in the area around the armpit and collar bone area around the armpit and collar bone (axillary-subclavian vein thrombosis), in (axillary-subclavian vein thrombosis), in the upper arm, abdomen, or pelvic region.the upper arm, abdomen, or pelvic region.
IntroductionIntroduction
IntroductionIntroduction
Deep vein thrombosis most often occurs in:Deep vein thrombosis most often occurs in:Hospitalized patients Hospitalized patients
following surgery. following surgery. Individuals confined to bed for Individuals confined to bed for
prolonged periods. prolonged periods. Healthy individuals whose legs Healthy individuals whose legs
remain immobilized for long remain immobilized for long stretches of time, such as passengers stretches of time, such as passengers on lengthy airline flights.on lengthy airline flights.
IntroductionIntroduction Some people are more likely than others to Some people are more likely than others to
develop thrombosis. Those at risk include:develop thrombosis. Those at risk include: The elderly The elderly Diabetics Diabetics People with blood disorders People with blood disorders Women who take oral contraceptives (birth control Women who take oral contraceptives (birth control
pills) or other medications that contain the hormone pills) or other medications that contain the hormone estrogen estrogen
People with a history of thrombosis People with a history of thrombosis People who have just undergone major surgeries or People who have just undergone major surgeries or
have just suffered a bone fracturehave just suffered a bone fracture
IntroductionIntroductionDeep vein thrombosis is the Deep vein thrombosis is the
second most common vascular problem in second most common vascular problem in the United States. (The first is the United States. (The first is varicose varicose veins.)veins.)
The condition is most commonly seen in The condition is most commonly seen in people over age 60, but anyone can be people over age 60, but anyone can be affected affected
DVT is a dangerous condition because the DVT is a dangerous condition because the clot may become dislodged from the vein clot may become dislodged from the vein and travel inside the vein to the lung, and travel inside the vein to the lung, where it may get trapped and block a where it may get trapped and block a vessel in the lung. vessel in the lung.
This is called pulmonary embolism, which This is called pulmonary embolism, which can be deadly. can be deadly.
Pulmonary embolism (PE) is an extremely Pulmonary embolism (PE) is an extremely common and highly lethal condition that is common and highly lethal condition that is a leading cause of death in all age groups.a leading cause of death in all age groups.
PE FACTSPE FACTS
It is the first or second most common cause of unexpected death in It is the first or second most common cause of unexpected death in most age groups. most age groups.
Nine out of 10 cases of pulmonary embolism are caused by blood Nine out of 10 cases of pulmonary embolism are caused by blood clots that form in the legs and then travel to the lungs. clots that form in the legs and then travel to the lungs.
33rdrd most common cause of death in the US. most common cause of death in the US. More than 600,000 people in the United States have a pulmonary More than 600,000 people in the United States have a pulmonary
embolism each year, and more than 10 percent of embolism each year, and more than 10 percent of them die from it. them die from it.
Most who die do so within 30 to 60 Most who die do so within 30 to 60 minutes after symptoms start. minutes after symptoms start.
DVT of the calf is a significant source of DVT of the calf is a significant source of PE and often causes serious morbidity or PE and often causes serious morbidity or death. death.
In fact, 1/3 of the cases of massive PE In fact, 1/3 of the cases of massive PE have their only identified source in the have their only identified source in the veins of the calf. veins of the calf.
PE FactsPE Facts
Prompt diagnosis and treatment can Prompt diagnosis and treatment can dramatically reduce the mortality rate and dramatically reduce the mortality rate and morbidity of the disease. morbidity of the disease.
Unfortunately, the diagnosis is missed far Unfortunately, the diagnosis is missed far more often than it is made, because PE more often than it is made, because PE often causes only vague and nonspecific often causes only vague and nonspecific symptoms. symptoms.
Because PE is both extremely common and fairly difficult Because PE is both extremely common and fairly difficult to diagnose, many patients are seen in the ED and later to diagnose, many patients are seen in the ED and later die from undiagnosed PE. die from undiagnosed PE.
In fact, respiratory complaints are the most common In fact, respiratory complaints are the most common complaints in patients who are seen alive in the ED and complaints in patients who are seen alive in the ED and later die unexpectedly later die unexpectedly
IntroductionIntroduction
PathophysiologyPathophysiology Pulmonary thromboembolism is not a Pulmonary thromboembolism is not a
disease in and of itself. disease in and of itself.
It is an often fatal complication of It is an often fatal complication of underlying venous thrombosis. underlying venous thrombosis.
Under normal conditions, Under normal conditions, microthrombi (tiny aggregates of microthrombi (tiny aggregates of red cells, platelets, and fibrin) red cells, platelets, and fibrin) are formed and lysed continually are formed and lysed continually within the venous circulatory system. within the venous circulatory system.
This dynamic equilibrium ensures local This dynamic equilibrium ensures local hemostasis in response to injury without hemostasis in response to injury without permitting uncontrolled propagation of clot.permitting uncontrolled propagation of clot.
PathophysiologyPathophysiology
PathophysiologyPathophysiology Under pathological conditions, Under pathological conditions,
microthrombi may escape the normal microthrombi may escape the normal fibrinolytic system to grow and propagate. fibrinolytic system to grow and propagate.
PE occurs when these propagating clots PE occurs when these propagating clots break loose and embolize to block break loose and embolize to block pulmonary blood vessels.pulmonary blood vessels.
Abnormal thrombus formation can be caused by Abnormal thrombus formation can be caused by either: either: stasis of blood flowstasis of blood flow hypercoagulability of the bloodhypercoagulability of the blood or damage to the endothelial lining of the veins. or damage to the endothelial lining of the veins.
These 3 underlying causes are known as the These 3 underlying causes are known as the Virchow triad. Virchow triad.
All known clinical risk factors for DVT and PE All known clinical risk factors for DVT and PE have their basis in one or more of the triad. have their basis in one or more of the triad.
PathophysiologyPathophysiology
Virchow’s triadVirchow’s triad
Thrombosis in the veins is Thrombosis in the veins is triggered by venostasis, triggered by venostasis, hypercoagulability, and vessel hypercoagulability, and vessel wall inflammation. wall inflammation.
Conditions that can cause Conditions that can cause venous stasisvenous stasis are: are: varicose veins, obesity, surgery, varicose veins, obesity, surgery,
prolonged bed rest, CHF prolonged bed rest, CHF and pregnancy. and pregnancy.
Virchow’s triadVirchow’s triad
PE is the most common cause of maternal PE is the most common cause of maternal death. The risk of venous thrombo-death. The risk of venous thrombo-embolism is 6× greater in pregnant embolism is 6× greater in pregnant women. women.
Virchow’s triadVirchow’s triad
Conditions that may cause Conditions that may cause hypercoagulationhypercoagulation are: are: malignant neoplasms, blood diseases that malignant neoplasms, blood diseases that
raise the platelet count, decreased raise the platelet count, decreased fibrinolysis, inherited coagulopathies, fibrinolysis, inherited coagulopathies, dehydration, increase in the clotting factors dehydration, increase in the clotting factors that increase blood viscosity, and oral that increase blood viscosity, and oral contraceptives or drugs that may enhance contraceptives or drugs that may enhance clotting. clotting.
Virchow’s triadVirchow’s triad
Conditions that may cause Conditions that may cause endothelial endothelial injuryinjury are: are: IV injections, severe trauma and major IV injections, severe trauma and major
orthopedic injury or surgery, contrast media orthopedic injury or surgery, contrast media for x-rays, and certain antibiotics. for x-rays, and certain antibiotics.
Virchow’s triadVirchow’s triad
Conditions that may cause Conditions that may cause vascular wall vascular wall injuryinjury are: are: severe trauma with major orthopedic injury, severe trauma with major orthopedic injury,
major surgery, indwelling IV catheters, major surgery, indwelling IV catheters, injections of irritating substances such as injections of irritating substances such as contrast media and certain antibiotics, IV drug contrast media and certain antibiotics, IV drug abuse and prior deep vein thrombosis. abuse and prior deep vein thrombosis.
Virchow’s triadVirchow’s triad
Signs and symptoms of venous Signs and symptoms of venous thromboembolic disease may include: thromboembolic disease may include: chronic edema chronic edema pain (claudication) pain (claudication) altered pigmentation altered pigmentation induration induration
Virchow’s triadVirchow’s triad
FrequencyFrequencySurgical patients have long been Surgical patients have long been
recognized to be at special risk for DVT recognized to be at special risk for DVT and PE, but the problem is not confined to and PE, but the problem is not confined to surgical patients. surgical patients.
PE is the most common cause of maternal PE is the most common cause of maternal death. The risk of venous thrombo-death. The risk of venous thrombo-embolism is 6× greater in pregnant embolism is 6× greater in pregnant women. women.
Massive PE is one of the most common Massive PE is one of the most common causes of unexpected deathcauses of unexpected deathsecond only to coronary artery disease as a second only to coronary artery disease as a
cause of sudden unexpected natural death at cause of sudden unexpected natural death at any age any age
The diagnosis is unsuspected until The diagnosis is unsuspected until autopsy in approximately 80% of cases. autopsy in approximately 80% of cases.
Mortality/MorbidityMortality/Morbidity
Although PE often is fatal, prompt Although PE often is fatal, prompt diagnosis and treatment can reduce the diagnosis and treatment can reduce the mortality rate dramatically. mortality rate dramatically. Approximately 10% of patients in whom acute Approximately 10% of patients in whom acute
PE is diagnosed die within the first 60 PE is diagnosed die within the first 60 minutes. minutes.
Of the remainder, the condition eventually is Of the remainder, the condition eventually is diagnosed and treated in one third and diagnosed and treated in one third and remains undiagnosed in two thirds. remains undiagnosed in two thirds.
..
Mortality/MorbidityMortality/Morbidity
Mortality/MorbidityMortality/MorbidityPatients who survive an acute PE are at Patients who survive an acute PE are at
high risk for recurrent PE and for the high risk for recurrent PE and for the development of pulmonary hypertension development of pulmonary hypertension and chronic cor pulmonale right vent and chronic cor pulmonale right vent hypertrophy and failurehypertrophy and failure
This occurs in up to 70% of patients and This occurs in up to 70% of patients and carries its own attendant mortality and carries its own attendant mortality and morbidity morbidity
HistoryHistoryPE is so common and so lethal that the PE is so common and so lethal that the
diagnosis should be sought actively in diagnosis should be sought actively in every patient who presents with any chest every patient who presents with any chest symptoms that cannot be proven to have symptoms that cannot be proven to have another cause another cause
HistoryHistorySymptoms that should provoke a Symptoms that should provoke a
suspicion of PE must include:suspicion of PE must include: chest pain, chest wall tenderness, back pain, chest pain, chest wall tenderness, back pain,
shoulder pain, upper abdominal pain, shoulder pain, upper abdominal pain, syncope, hemoptysis, shortness of breath, syncope, hemoptysis, shortness of breath, painful respiration, new onset of wheezing, painful respiration, new onset of wheezing, any new cardiac arrhythmia, or any other any new cardiac arrhythmia, or any other unexplained symptom referable to the thorax unexplained symptom referable to the thorax
HistoryHistoryThe classic triad of signs and symptoms of The classic triad of signs and symptoms of
PE (hemoptysis, dyspnea, chest pain) are PE (hemoptysis, dyspnea, chest pain) are neither sensitive nor specific. neither sensitive nor specific. They occur in fewer than 20% of patients in They occur in fewer than 20% of patients in
whom the diagnosis of PE is made, whom the diagnosis of PE is made, Most patients with those symptoms are found Most patients with those symptoms are found
to have some etiology other than PE to to have some etiology other than PE to account for them. account for them.
HistoryHistory Of patients who go on to die from massive PE:Of patients who go on to die from massive PE:
60% have dyspnea60% have dyspnea 17% have chest pain17% have chest pain 3% have hemoptysis3% have hemoptysis
Many patients with PE are initially completely Many patients with PE are initially completely asymptomatic, and most of those who do have asymptomatic, and most of those who do have symptoms have an atypical presentation symptoms have an atypical presentation
HistoryHistoryThese patients usually lack any other These patients usually lack any other
classical signs, symptoms, or known risk classical signs, symptoms, or known risk factors for pulmonary thromboembolism. factors for pulmonary thromboembolism.
Such patients often are dismissed Such patients often are dismissed inappropriately with an inadequate workup inappropriately with an inadequate workup and a nonspecific diagnosis, such as and a nonspecific diagnosis, such as musculoskeletal chest pain or pleurisy. musculoskeletal chest pain or pleurisy.
PhysicalPhysicalMassive PE causes hypotension due to Massive PE causes hypotension due to
acute cor pulmonaleacute cor pulmonalePhysical examination findings early in Physical examination findings early in
submassive PE may be completely submassive PE may be completely normal. normal.
Initially, abnormal physical findings are Initially, abnormal physical findings are absent in most patients with PE. absent in most patients with PE.
PhysicalPhysicalAfter 24-72 hours, loss of pulmonary After 24-72 hours, loss of pulmonary
surfactant often causes atelectasis and surfactant often causes atelectasis and alveolar infiltrates that are alveolar infiltrates that are indistinguishable from pneumonia on indistinguishable from pneumonia on clinical examination and by x-ray clinical examination and by x-ray
Causes: Hypercoagulable states Causes: Hypercoagulable states
Prolonged venous stasis or significant injury to Prolonged venous stasis or significant injury to the veins can provoke DVT and PE in any the veins can provoke DVT and PE in any person,person, increasing evidence suggests that spontaneous DVT increasing evidence suggests that spontaneous DVT
and PE nearly always are related to some underlying and PE nearly always are related to some underlying hypercoagulable state. hypercoagulable state.
Other identified "causes" most likely serve only Other identified "causes" most likely serve only as triggers for a system that is already out of as triggers for a system that is already out of balance. balance.
Hypercoagulable states may be acquired Hypercoagulable states may be acquired or congenital. or congenital. An inborn resistance to activated protein C is An inborn resistance to activated protein C is
the most common congenital risk factor for the most common congenital risk factor for DVT that has been identified to date. DVT that has been identified to date.
Most patients with this syndrome have a Most patients with this syndrome have a genetic mutation in factor V known as "factor genetic mutation in factor V known as "factor V Leyden," although other mechanisms also V Leyden," although other mechanisms also can produce a resistance to activated protein can produce a resistance to activated protein C C
Causes: Hypercoagulable states Causes: Hypercoagulable states
Primary or acquired deficiencies in protein Primary or acquired deficiencies in protein C, protein S, or antithrombin III are also C, protein S, or antithrombin III are also common underlying causes of DVT and common underlying causes of DVT and PE PE
Causes: Hypercoagulable states Causes: Hypercoagulable states
Risk MarkersRisk MarkersThe most important clinically identifiable The most important clinically identifiable
risk markers for DVT and PE are:risk markers for DVT and PE are:prior history of DVT or PEprior history of DVT or PE recent surgery or pregnancyrecent surgery or pregnancyprolonged immobilizationprolonged immobilizationunderlying malignancy / Trousseau’s underlying malignancy / Trousseau’s
syndrome= cancer +recurrent superficial and syndrome= cancer +recurrent superficial and Deep Venous ThrombosisDeep Venous Thrombosis
Other recognized markers of risk for venous Other recognized markers of risk for venous thromboembolic diseasethromboembolic disease
AIDS (lupus anticoagulant) AIDS (lupus anticoagulant) Antithrombin III deficiencyAntithrombin III deficiency Behçet disease Behçet disease Blood type A Blood type A Burns Burns Catheters (indwelling venous infusion catheters) Catheters (indwelling venous infusion catheters) Chemotherapy Chemotherapy Congestive heart failure (CHF)Congestive heart failure (CHF) Drug abuse (intravenous [IV] drugs) Drug abuse (intravenous [IV] drugs) Drug-induced lupus anticoagulant Drug-induced lupus anticoagulant DVT in the past DVT in the past Estrogen replacements (high dose only) Estrogen replacements (high dose only)
Fibrinogen abnormalityFibrinogen abnormality Fractures Fractures Hemolytic anemias Hemolytic anemias Heparin-associated thrombocytopenia Heparin-associated thrombocytopenia Homocystinuria Homocystinuria Hyperlipidemias Hyperlipidemias ImmobilizationImmobilization Malignancy Malignancy Myocardial infarction Myocardial infarction Obesity Obesity Old ageOld age
Other recognized markers of risk for venous Other recognized markers of risk for venous
thromboembolic diseasethromboembolic disease
Oral contraceptives Oral contraceptives PE in the past PE in the past Phenothiazine Phenothiazine Plasminogen abnormality Plasminogen abnormality Plasminogen activator abnormality Plasminogen activator abnormality PolycythemiaPolycythemia PostoperativePostoperative Postpartum period Postpartum period Pregnancy Pregnancy Protein C deficiency Protein C deficiency Protein S deficiencyProtein S deficiency Resistance to activated protein CResistance to activated protein C Systemic lupus erythematosus Systemic lupus erythematosus
Other recognized markers of risk for venous Other recognized markers of risk for venous
thromboembolic diseasethromboembolic disease
Thrombocytosis Thrombocytosis Trauma Trauma Ulcerative colitis Ulcerative colitis Varicose veins Varicose veins VenographyVenographyVenous pacemakersVenous pacemakersVenous stasisVenous stasisWarfarin (first few days of therapy)Warfarin (first few days of therapy)
Other recognized markers of risk for venous Other recognized markers of risk for venous
thromboembolic diseasethromboembolic disease
Other Problems to be Other Problems to be ConsideredConsidered
Whether the presentation of the patient Whether the presentation of the patient with pulmonary thromboembolism is with pulmonary thromboembolism is typical or atypical, the list of differential typical or atypical, the list of differential diagnoses remains extensive and the true diagnoses remains extensive and the true diagnosis must be sought actively diagnosis must be sought actively
Diagnostic Work-UpDiagnostic Work-Up Clinical variables alone lack sufficient power to Clinical variables alone lack sufficient power to
permit a treatment decisionpermit a treatment decision
patients in whom PE is suspected must undergo patients in whom PE is suspected must undergo diagnostic tests until the diagnosis is proven or diagnostic tests until the diagnosis is proven or ruled out, or until some alternative diagnosis is ruled out, or until some alternative diagnosis is proven.proven.
no known blood or serum test can move a patient no known blood or serum test can move a patient with a high clinical likelihood of pulmonary with a high clinical likelihood of pulmonary thromboembolism into a low likelihood category thromboembolism into a low likelihood category or vice versaor vice versa
Lab StudiesLab Studies The PO2 on arterial blood gases analysis (ABG) The PO2 on arterial blood gases analysis (ABG)
has a zero or even negative predictive value in a has a zero or even negative predictive value in a typical population of patients in whom PE is typical population of patients in whom PE is suspected clinically suspected clinically
Clotting study results are normal in most patients Clotting study results are normal in most patients with pulmonary thromboembolism with pulmonary thromboembolism
The white blood cell (WBC) count may be The white blood cell (WBC) count may be normal or elevated. normal or elevated. A WBC count as high as 20,000 is not uncommon in A WBC count as high as 20,000 is not uncommon in
patients with PE patients with PE
Lab StudiesLab StudiesAt the present time, D-dimer is not At the present time, D-dimer is not
sensitive or specific enough to change the sensitive or specific enough to change the course of diagnostic evaluation or course of diagnostic evaluation or treatment for patients with suspected PE treatment for patients with suspected PE
A-a gradientA-a gradient PAO2-PaO2PAO2-PaO2PAO2=150-(1.25xPCO2) use PaCo2 from PAO2=150-(1.25xPCO2) use PaCo2 from
the ABG for PCO2the ABG for PCO2Assumes room air FiO2=21%@sealevelAssumes room air FiO2=21%@sealevelNormal 10-15Normal 10-15
Radiologic Studies - CXRRadiologic Studies - CXR initial chest x-ray (CXR) findings of a patient initial chest x-ray (CXR) findings of a patient
with PE are virtually always normal with PE are virtually always normal Rarely may show Westermark sign – Rarely may show Westermark sign –
dilatation of the pulmonary vessels proximal to an dilatation of the pulmonary vessels proximal to an embolism along with collapse of distal vessels, embolism along with collapse of distal vessels, sometimes with a sharp cutoff. sometimes with a sharp cutoff.
Over time, an initially normal CXR often begins to Over time, an initially normal CXR often begins to show atelectasisshow atelectasis which may progress to cause a small pleural effusion which may progress to cause a small pleural effusion
and an elevated hemidiaphragm. and an elevated hemidiaphragm.
After 24-72 hours, 1/3 of patients with proven After 24-72 hours, 1/3 of patients with proven PE develop focal infiltrates that are PE develop focal infiltrates that are indistinguishable from an infectious indistinguishable from an infectious pneumonia. pneumonia.
Rare late finding of pulmonary infarction is the Rare late finding of pulmonary infarction is the Hampton humpHampton hump a triangular or rounded pleural-based infiltrate with a triangular or rounded pleural-based infiltrate with
the apex pointed toward the hilum, frequently the apex pointed toward the hilum, frequently located adjacent to the diaphragm.located adjacent to the diaphragm.
Radiologic Studies - CXRRadiologic Studies - CXR
Radiologic Studies – V/Q Scan Radiologic Studies – V/Q Scan Nuclear scintigraphic ventilation-perfusion Nuclear scintigraphic ventilation-perfusion
(V/Q) scanning of the lung (V/Q) scanning of the lung
One of the most important diagnostic One of the most important diagnostic modality for detecting pulmonary modality for detecting pulmonary thromboembolismthromboembolism
V/Q scan is indicated whenever the V/Q scan is indicated whenever the diagnosis of PE is suspected and no diagnosis of PE is suspected and no alternative diagnosis can be proved. alternative diagnosis can be proved.
V/Q also is indicated for most patients with V/Q also is indicated for most patients with DVT even without symptoms of PE DVT even without symptoms of PE
Radiologic Studies – V/Q Scan Radiologic Studies – V/Q Scan
Pulmonary AngiographyPulmonary Angiographya nondiagnostic V/Q pattern is not an a nondiagnostic V/Q pattern is not an
acceptable endpoint in the workup for acceptable endpoint in the workup for pulmonary thromboembolism. pulmonary thromboembolism.
Pulmonary angiography or another Pulmonary angiography or another definitive test must be performed when the definitive test must be performed when the diagnosis remains uncertain diagnosis remains uncertain
Pulmonary angiographyPulmonary angiographyPulmonary angiography remains the Pulmonary angiography remains the
criterion standard for the diagnosis of PE criterion standard for the diagnosis of PE
a positive pulmonary angiogram provides a positive pulmonary angiogram provides virtually 100% certainty that an obstruction to virtually 100% certainty that an obstruction to pulmonary arterial blood flow does exist. pulmonary arterial blood flow does exist.
a negative pulmonary angiogram provides a negative pulmonary angiogram provides greater than 90% certainty in the exclusion of greater than 90% certainty in the exclusion of PE PE
CTACTAHigh-resolution helical (spiral) computed High-resolution helical (spiral) computed
tomographic angiography (CTA) is a tomographic angiography (CTA) is a promising technique that soon may promising technique that soon may replace VQ scans replace VQ scans
UltrasoundUltrasoundThe diagnosis of PE can be proven by The diagnosis of PE can be proven by
demonstrating the presence of a DVT at demonstrating the presence of a DVT at any site. This may be accomplished any site. This may be accomplished noninvasively, by using duplex ultrasound. noninvasively, by using duplex ultrasound.
UltrasoundUltrasound To look for DVT using ultrasound, the ultrasound To look for DVT using ultrasound, the ultrasound
transducer is placed against the skin and then is transducer is placed against the skin and then is pressed inward firmly enough to compress the pressed inward firmly enough to compress the vein being examined. vein being examined. In an area of normal veins, the veins are easily In an area of normal veins, the veins are easily
compressed completely closed, while the muscular compressed completely closed, while the muscular arteries are extremely resistant to compression. arteries are extremely resistant to compression.
Where DVT is present, the veins do not collapse Where DVT is present, the veins do not collapse completely when pressure is applied using the completely when pressure is applied using the ultrasound probe ultrasound probe
UltrasoundUltrasoundA negative ultrasound scan does not rule out A negative ultrasound scan does not rule out
DVT, many DVTs occur in areas that are DVT, many DVTs occur in areas that are inaccessible to ultrasonic examination. inaccessible to ultrasonic examination.
Before an ultrasound scan can be considered Before an ultrasound scan can be considered negative, the entire deep venous system must negative, the entire deep venous system must be interrogated using centimeter-by-be interrogated using centimeter-by-centimeter compression testing of every centimeter compression testing of every vessel.vessel.
UltrasoundUltrasound In two thirds of patients with PE, the site of In two thirds of patients with PE, the site of
DVT cannot be visualized by ultrasound, DVT cannot be visualized by ultrasound, so a negative duplex ultrasound does not so a negative duplex ultrasound does not markedly reduce the likelihood of PEmarkedly reduce the likelihood of PE
ElectrocardiogramElectrocardiogram
The most common ECG abnormalities in the The most common ECG abnormalities in the setting of PE are tachycardia and nonspecific setting of PE are tachycardia and nonspecific ST-T wave abnormalities.ST-T wave abnormalities.
Any other ECG abnormality may appear with Any other ECG abnormality may appear with equal likelihood, but none are sensitive or equal likelihood, but none are sensitive or specific for PE.specific for PE.
The classic findings of right heart strain and The classic findings of right heart strain and acute cor pulmonale are tall, peaked P waves acute cor pulmonale are tall, peaked P waves in lead II (P pulmonale), right axis deviation, in lead II (P pulmonale), right axis deviation, right bundle-branch block, an S1-Q3-T3 right bundle-branch block, an S1-Q3-T3 pattern, or atrial fibrillation. pattern, or atrial fibrillation. Unfortunately, only 20% of patients with proven PE Unfortunately, only 20% of patients with proven PE
have any of these classic ECG abnormalities.have any of these classic ECG abnormalities.
ElectrocardiogramElectrocardiogram
TreatmentTreatmentFibrinolytic therapy Fibrinolytic therapy
standard of care for all patients with massive standard of care for all patients with massive or unstable PE since the 1970s. or unstable PE since the 1970s.
a rapidly acting fibrinolytic agent should be a rapidly acting fibrinolytic agent should be administered immediately to every patient administered immediately to every patient who has suffered any degree of hypotension who has suffered any degree of hypotension or is significantly hypoxemic from PE, unless or is significantly hypoxemic from PE, unless overwhelming contraindications.overwhelming contraindications.
TX-Fibrinolytic therapyTX-Fibrinolytic therapyFibrinolytic therapy dramatically reduces Fibrinolytic therapy dramatically reduces
the mortality rate, morbidity, and rate of the mortality rate, morbidity, and rate of recurrence of PE regardless of the size or recurrence of PE regardless of the size or type of PE at the time of presentationtype of PE at the time of presentation
Fibrinolysis is indicated overwhelmingly for any Fibrinolysis is indicated overwhelmingly for any patient with a PE large enough to cause patient with a PE large enough to cause hypotension, even if the hypotension is transient hypotension, even if the hypotension is transient or correctable. or correctable.
Early fibrinolysis is expected to reduce the Early fibrinolysis is expected to reduce the mortality rate by 50% for patients who have right mortality rate by 50% for patients who have right ventricular dysfunction due to PE, even if they ventricular dysfunction due to PE, even if they are hemodynamically stable. are hemodynamically stable.
TX-Fibrinolytic therapyTX-Fibrinolytic therapy
TX-HeparinTX-HeparinHeparin reduces the mortality rate of PE Heparin reduces the mortality rate of PE
because it slows or prevents clot because it slows or prevents clot progression and reduces the risk of further progression and reduces the risk of further embolism embolism
Bolus 80U/kg -Drip 15u/kg/hrBolus 80U/kg -Drip 15u/kg/hrMonitor aPTT 1.5-2x baselineMonitor aPTT 1.5-2x baselineHIT-antibody mediated 5-12 days pRxHIT-antibody mediated 5-12 days pRxLMW heparins 1mg/kg SQLMW heparins 1mg/kg SQ
TX-HeparinTX-HeparinEarly heparin anticoagulation is so essential Early heparin anticoagulation is so essential
that heparin should be started as soon as the that heparin should be started as soon as the diagnosis of pulmonary thromboembolism is diagnosis of pulmonary thromboembolism is considered seriously. considered seriously.
Anticoagulation should not wait for the results Anticoagulation should not wait for the results of diagnostic tests: if anticoagulation is of diagnostic tests: if anticoagulation is delayed, venous thrombosis and PE may delayed, venous thrombosis and PE may progress rapidly.progress rapidly.
TX- OxygenTX- OxygenOxygen should be administered to every Oxygen should be administered to every
patient with suspected PE, even when the patient with suspected PE, even when the arterial PO2 is perfectly normal, because arterial PO2 is perfectly normal, because increased alveolar oxygen may help to increased alveolar oxygen may help to promote pulmonary vascular dilatation promote pulmonary vascular dilatation
Compression stockingsCompression stockingsCompression stockings that provide a 30-Compression stockings that provide a 30-
40 mm Hg compression gradient should 40 mm Hg compression gradient should be usedbe usedsafe and effective adjunctive treatment that safe and effective adjunctive treatment that
can limit or prevent extension of thrombus can limit or prevent extension of thrombus effective in the prophylaxis of effective in the prophylaxis of
thromboembolism thromboembolism effective in preventing progression of effective in preventing progression of
thrombus in patients who already have DVT thrombus in patients who already have DVT and PE and PE
MedicationsMedications Immediate full anticoagulation is Immediate full anticoagulation is
mandatory for all patients with suspected mandatory for all patients with suspected DVT or PEDVT or PEeffective anticoagulation with heparin reduces effective anticoagulation with heparin reduces
the mortality rate of PE from 30% to less than the mortality rate of PE from 30% to less than 10%. 10%.
Anticoagulation is essential, but Anticoagulation is essential, but anticoagulation alone does not guarantee anticoagulation alone does not guarantee a successful outcome. a successful outcome.
DVT and PE may recur or extend despite DVT and PE may recur or extend despite full and effective heparin anticoagulation full and effective heparin anticoagulation
MedicationsMedications
Fibrinolysis is always indicated for Fibrinolysis is always indicated for hemodynamically unstable patients with hemodynamically unstable patients with PE, because no other medical therapy can PE, because no other medical therapy can improve acute cor pulmonale quickly improve acute cor pulmonale quickly enough to save the patient's life enough to save the patient's life
MedicationsMedications
Fibrinolytic regimens currently in common Fibrinolytic regimens currently in common use for PE include 2 forms of recombinant use for PE include 2 forms of recombinant tissue plasminogen activator, t-PA tissue plasminogen activator, t-PA (alteplase) and r-PA (reteplase), along (alteplase) and r-PA (reteplase), along with urokinase and streptokinase. with urokinase and streptokinase.
MedicationsMedications
Alteplase usually is given as a front-loaded Alteplase usually is given as a front-loaded infusion over 90 or 120 minutes. infusion over 90 or 120 minutes.
Urokinase and streptokinase usually are Urokinase and streptokinase usually are given as infusions over 24 hours or more. given as infusions over 24 hours or more.
Reteplase is a new-generation Reteplase is a new-generation thrombolytic with a longer half-life that is thrombolytic with a longer half-life that is given as a single bolus or as 2 boluses given as a single bolus or as 2 boluses administered 30 minutes apart. administered 30 minutes apart.
MedicationsMedications
Long-term anticoagulation is essential for Long-term anticoagulation is essential for patients who survive an initial DVT or PE. patients who survive an initial DVT or PE.
MedicationsMedications
The optimum total duration of The optimum total duration of anticoagulation has been controversial in anticoagulation has been controversial in recent years, but general consensus holds recent years, but general consensus holds that at least 6 months of anticoagulation is that at least 6 months of anticoagulation is associated with significant reduction in associated with significant reduction in recurrences and a net positive benefitrecurrences and a net positive benefit
MedicationsMedications
Prompt diagnosis and treatment can Prompt diagnosis and treatment can dramatically reduce the mortality rate and dramatically reduce the mortality rate and morbidity of PE morbidity of PE
PE often causes only vague and PE often causes only vague and nonspecific symptomsnonspecific symptoms
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