Pulmonary Embolism (PE)
Pulmonary Embolism (PE) Examination
A pulmonary embolism (PE) is a serious and potentially life-threatening medical condition that occurs when a blood clot (usually from the deep veins of the legs or pelvis, known as deep vein thrombosis) travels to the lungs and blocks one or more pulmonary arteries. This obstruction can impede blood flow to the lungs, leading to various complications, including respiratory distress and cardiac issues.
In the prehospital setting, the early recognition and management of pulmonary embolisms can improve patient outcomes.
Risk Factors
Several risk factors can increase the likelihood of developing a pulmonary embolism. It’s important to note that having one or more risk factors does not necessarily mean someone will experience a pulmonary embolism. Common risk factors include:
Deep Vein Thrombosis
Most pulmonary embolisms arise from blood clots formed in the deep veins of the legs (DVT). If a DVT breaks loose and travels to the lungs, it can result in a pulmonary embolism. Read more on DVTs here.
Immobility or Prolonged Bed Rest
Long periods of immobility, such as during long flights or bed rest after surgery, can increase the risk of blood clot formation.
Surgery
Major surgeries, particularly orthopaedic surgeries like hip or knee replacement, can increase the risk of blood clot formation.
Trauma or Injury
Severe injuries, fractures, or trauma can lead to blood clot formation.
Cancer
Certain types of cancer, especially those that affect the lungs, can increase the risk of blood clot formation.
Smoking
Tobacco smoke can damage blood vessels and increase the risk of clot formation.
Pregnancy
Pregnancy and the postpartum period increase the risk of blood clot formation due to changes in blood flow and hormonal factors.
History Of PE
Individuals who have had a previous pulmonary embolism or deep vein thrombosis are at an increased risk of recurrence.
Clinical Features
A diagnosis of pulmonary embolism (PE) cannot rely solely on physical examination. In many cases, clinical examination may not reveal significant findings, and unless you actively consider PE as a potential cause for a patient’s chest pain or shortness of breath, the diagnosis may be overlooked.
Symptoms
Dyspnoea (Shortness of Breath): Sudden onset of difficulty breathing is a hallmark symptom of PE. It may range from mild to severe and can occur at rest or with exertion.
Pleuritic Chest Pain: Often worsens with deep breaths or coughing.
Cough: Some individuals may experience cough, which can be non-specific and may or may not produce bloody sputum.
Haemoptysis: Coughing up blood or bloody sputum can occur.
Syncope of Dizziness: Due to haemodynamic instability.
Clinical Findings
Tachycardia: an elevated heart rate may be observed as the heart tries to compensate for decreased oxygenation.
Tachypnoea: Rapid breathing is a common respiratory response to decreased oxygen levels in the blood.
Cyanosis: Bluish discoloration of the skin or mucous membranes may be observed due to inadequate oxygenation.
Evidence Of DVTs: Read more on DVTs here.
Hypotension: Could signify strain on right ventricles
Pleural Rub: A squeaking or grating noise arises when ischemic lung tissue makes contact with the pleura.
Management
Utilising the ABCDE approach facilitates a structured assessment of a suspected pulmonary embolism. Each phase of the ABCDE approach entails clinical assessment, investigations, and interventions. Issues are tackled as they are discovered, and regular reassessment is needed to check for a response to interventions. You can read more on DRCABCDE Here.
A – Airway
Assessment
This step assesses the patient’s airway for any obstructions or compromise. If the patient can talk, their airway is patent and can move on in the algorithm.
If the patient is unable to talk, look for signs of airway compromise:
- Cyanosis
- Use of accessory muscles, flaring nostrils, retraction of chest wall.
- Added breath sounds (wheeze, stridor, gurgling, rasping sounds).
- Diminished or absent breath sounds.
- See-saw breathing.
- Agitation or restlessness.
- Decreased levels of consciousness, disorientation, confusion.
- Inability to cough effectively.
Interventions
If airway issues have been found, then you cannot move on in the algorithm until these have been fixed. Often, some basic airway manoeuvres can help correct airway issues.
Head-tilt chin-lift, jaw thrust, oropharyngeal, nasopharyngeal, and supraglottic airways can be used to fix issues.
Ensure to reassess after any interventions.
B – Breathing
Assessment
Firstly, patient’s Respiration Rate should be recorded.
Typically, a normal respiratory rate falls within the range of 12-20 breaths per minute. In cases of pulmonary embolism (PE), tachypnoea may occur as a compensatory mechanism to address the ventilation-perfusion mismatch commonly associated with pulmonary embolisms (PE).
Secondly, Oxygen Saturation (SpO2) should be obtained.
In healthy individuals, a normal SpO2 range is 94-98%, while for patients with chronic obstructive pulmonary disease (COPD) who are prone to retaining CO2, the range is 88-92%. It is noteworthy that hypoxemia is a characteristic clinical feature observed in pulmonary embolism.
A full chest examination should be carried out, with particular attention to Auscultation and Percussion.
In pulmonary embolism, air entry is generally normal, but there may be a reduction in specific areas corresponding to infarcted lung tissue. The presence of coarse crackles or pleural rub during auscultation may indicate a pleural effusion resulting from infarcted lung tissue.
Percussion may identify regions of dullness that could be indicative of pleural effusion or lobar collapse secondary to infarcted lung tissue.
Interventions
Oxygen should be administered on all sick patients during initial assessment, regardless of oxygen saturations. This can then be titrated based on oxygen saturations. Read more about Oxygen here. Sitting the patient upright may help with oxygenation in addition to some relief from the chest pain if present.
Assisted Ventilations with a bag-valve-mask may be needed if respiration rate is below 10 or above 30 with altered conscious level. A ventilation rate of around 10-12 (one every 6 seconds) should be adopted.
If no breathing rate is present or agonal/ineffective breathing, then resuscitation should be started with Chest Compressions and additional help requested.
Ensure to reassess after any interventions.
C – Circulation
Assessment
A bilateral assessment of Pulse should be carried out.
Patients with pulmonary embolism (PE) may exhibit tachycardia, although many may maintain a normal pulse rate.
A Blood Pressure should be recorded.
Significant pain associated with PE may lead to hypertension. However, if hypotension is present may suggest cardiac failure secondary to right heart strain, which can be seen in cases of massive pulmonary embolisms.
A Capillary Refill Time (CRT) should be assessed next.
Capillary Refill Time (CRT) may appear normal or sluggish if hypovolemia is present.
Jugular Venous Pressure (JVP) & Juglar Vein Distension (JVD) should be recorded.
An elevated JVP or JVD in the context of PE may indicate underlying right heart strain which signifies the possibility of a massive pulmonary embolism.
An ECG should be recorded.
Some ECG findings can suggest the presence of pulmonary embolisms. Sinus tachycardia is the predominant ECG finding in pulmonary embolism (PE).
Additional ECG findings related to PE encompass:
Onset of atrial fibrillation
Right axis deviation
Right bundle branch block
T wave inversion
S1Q3T3 pattern: characterised by S waves in lead I, Q waves in lead III, and T wave inversion in lead III.
Interventions
At this stage a Two-Level Wells Score can be calculated.
The first scoring table assesses the likeliness of Deep Vein Thrombosis, which can often be the cause of pulmonary embolisms. If the score is < 2 it indicates DVT unlikely or if score is > 2 then DVT is likely. You can read more on DVT here.
The second scoring table assesses the likeliness of Pulmonary Embolisms although a CT pulmonary angiogram can only definitely diagnosis a PE. A score of 4 or less indicates PE unlikely. A score of more than 4 indicates PE likely.
Intravenous Cannulation
Whilst prophylactic cannulation is not commonly practice prehospitally due to the risk of infection, if patient appears to be unstable or drug interventions needed then access should be obtained, ideally with a large bore cannula.
Intravenous Fluids
Intravenous fluids may be needed if patients is hypovolaemia. Read the article on fluid resuscitation here.
Ensure to reassess after any interventions.
D – Disability
Assessment
Level Of Consciousness should be assessed (AVPU) and Glasgow Coma Scale (GCS)
Evaluate the patient’s consciousness level by employing the AVPU scale:
Alert: The patient is fully alert, though not necessarily oriented.
Verbal: The patient provides some form of response when spoken to (e.g., words, grunt).
Pain: The patient reacts to a painful stimulus (e.g., supraorbital pressure).
Unresponsive: The patient shows no evidence of eye, voice, or motor responses to pain.
Read here to find out how to record a GCS.
Assessment of pupils should be carried out.
Inspect the size, symmetry, and reactiveness of the pupils in both eyes.
Blood Glucose should be recorded.
A normal blood glucose level should be between 4.0 – 8.0 mmol/L.
Interventions
Airway may need to be maintained if patients’ consciousness level is reduced.
Ensure to reassess after any interventions.
E – Exposure
Assessment
Leg Inspection should be carried out.
Inspect lower legs for evidence of DVTs.
Temperature should be recorded.
An increase in temperature may be noted in pulmonary embolism as part of the catecholamine (stress) response.
Pain score should be recorded, and appropriate analgesia given.
Reassessment
Perform a thorough re-evaluation of the patient using the ABCDE approach to detect any alterations in their clinical status and evaluate the impact of your prior interventions.
Swift recognition of deterioration is crucial, and immediate action should be taken.
Transport To ED
Transportation to ED should be swift in cases of suspected pulmonary embolisms and conveyed under emergency conditions. The patient should not be encouraged to walk, and manual handling techniques should be adopted to transfer patient to the ambulance.
Pre-alert to the nearest ED department should also be implemented, using either the ATMIST or SBAR handover tools.
Alternative Diagnosis
Pulmonary embolisms can manifest with symptoms that overlap with various other medical conditions. Some potential differential diagnoses to consider include:
Pneumonia: Inflammation of the lung tissue, often accompanied by fever, cough, and difficulty breathing.
Myocardial Infarction (Heart Attack): Chest pain and shortness of breath may resemble symptoms of a pulmonary embolism.
Asthma: Wheezing and breathlessness can be similar to pulmonary embolism symptoms.
Chronic Obstructive Pulmonary Disease (COPD): Chronic lung conditions like emphysema or chronic bronchitis may present with respiratory symptoms.
Anxiety/Panic Attacks: Palpitations, chest tightness, and shortness of breath may be attributed to anxiety or panic disorders.
Costochondritis: Inflammation of the chest wall cartilage can cause chest pain, which may mimic pulmonary embolism symptoms.
Pericarditis: Inflammation of the lining around the heart, leading to chest pain and discomfort.
Pleurisy: Inflammation of the membranes surrounding the lungs, resulting in sharp chest pain exacerbated by breathing.
Pulmonary Hypertension: Elevated blood pressure in the pulmonary arteries may cause symptoms resembling those of pulmonary embolism.
Rib Fracture: Trauma to the chest, causing pain and difficulty breathing.
Conclusion
Pulmonary embolisms (PE) represent a significant medical emergency with potentially life-threatening consequences. Timely recognition and appropriate prehospital management are crucial in improving outcomes for individuals affected by this condition.
The diverse and often subtle symptoms of PE, ranging from dyspnoea and chest pain to syncope, require a high index of suspicion on the part of the prehospital clinical. Rapid intervention, including supplemental oxygen, intravenous access, and pain management, contributes to maintaining adequate oxygenation and addressing immediate patient needs.
Key Points
- Pulmonary embolism (PE) is a potentially life-threatening condition characterised by the obstruction of one or more pulmonary arteries by a blood clot (embolus).
- The presentation of PE can vary widely, ranging from asymptomatic cases to sudden-onset symptoms such as chest pain (often pleuritic), shortness of breath, rapid breathing, cough (may be bloody), rapid heart rate, fainting, sweating, and anxiety.
- Management of PE aims to prevent further clot propagation, reduce the risk of recurrence, and alleviate symptoms.
Bibliography
NHS . (2019). Pulmonary embolism. NHS. https://www.nhs.uk/conditions/pulmonary-embolism
NICE. (2020, October). Pulmonary Embolism. NICE. https://cks.nice.org.uk/topics/pulmonary-embolism
Swaroop, M., & Tarbox, A. (2013). Pulmonary embolism. International Journal of Critical Illness and Injury Science, 3(1), 69. https://doi.org/10.4103/2229-5151.109427
Pulmonary Embolism (PE) Introduction
A pulmonary embolism (PE) is a serious and potentially life-threatening medical condition that occurs when a blood clot (usually from the deep veins of the legs or pelvis, known as deep vein thrombosis) travels to the lungs and blocks one or more pulmonary arteries. This obstruction can impede blood flow to the lungs, leading to various complications, including respiratory distress and cardiac issues.
In the prehospital setting, the early recognition and management of pulmonary embolisms can improve patient outcomes.
Risk Factors
Several risk factors can increase the likelihood of developing a pulmonary embolism. It’s important to note that having one or more risk factors does not necessarily mean someone will experience a pulmonary embolism. Common risk factors include:
Deep Vein Thrombosis
Most pulmonary embolisms arise from blood clots formed in the deep veins of the legs (DVT). If a DVT breaks loose and travels to the lungs, it can result in a pulmonary embolism. Read more on DVTs here.
Immobility or Prolonged Bed Rest
Long periods of immobility, such as during long flights or bed rest after surgery, can increase the risk of blood clot formation.
Surgery
Major surgeries, particularly orthopaedic surgeries like hip or knee replacement, can increase the risk of blood clot formation.
Trauma or Injury
Severe injuries, fractures, or trauma can lead to blood clot formation.
Cancer
Certain types of cancer, especially those that affect the lungs, can increase the risk of blood clot formation.
Smoking
Tobacco smoke can damage blood vessels and increase the risk of clot formation.
Pregnancy
Pregnancy and the postpartum period increase the risk of blood clot formation due to changes in blood flow and hormonal factors.
History Of PE
Individuals who have had a previous pulmonary embolism or deep vein thrombosis are at an increased risk of recurrence.
Clinical Features
A diagnosis of pulmonary embolism (PE) cannot rely solely on physical examination. In many cases, clinical examination may not reveal significant findings, and unless you actively consider PE as a potential cause for a patient’s chest pain or shortness of breath, the diagnosis may be overlooked.
Symptoms
Dyspnoea (Shortness of Breath): Sudden onset of difficulty breathing is a hallmark symptom of PE. It may range from mild to severe and can occur at rest or with exertion.
Pleuritic Chest Pain: Often worsens with deep breaths or coughing.
Cough: Some individuals may experience cough, which can be non-specific and may or may not produce bloody sputum.
Haemoptysis: Coughing up blood or bloody sputum can occur.
Syncope of Dizziness: Due to haemodynamic instability.
Clinical Findings
Tachycardia: an elevated heart rate may be observed as the heart tries to compensate for decreased oxygenation.
Tachypnoea: Rapid breathing is a common respiratory response to decreased oxygen levels in the blood.
Cyanosis: Bluish discoloration of the skin or mucous membranes may be observed due to inadequate oxygenation.
Evidence Of DVTs: Read more on DVTs here.
Hypotension: Could signify strain on right ventricles
Pleural Rub: A squeaking or grating noise arises when ischemic lung tissue makes contact with the pleura.
Clinical Features
Utilising the ABCDE approach facilitates a structured assessment of a suspected pulmonary embolism. Each phase of the ABCDE approach entails clinical assessment, investigations, and interventions. Issues are tackled as they are discovered, and regular reassessment is needed to check for a response to interventions. You can read more on DRCABCDE Here.
A – Airway
Assessment
This step assesses the patient’s airway for any obstructions or compromise. If the patient can talk, their airway is patent and can move on in the algorithm.
If the patient is unable to talk, look for signs of airway compromise:
- Cyanosis
- Use of accessory muscles, flaring nostrils, retraction of chest wall.
- Added breath sounds (wheeze, stridor, gurgling, rasping sounds).
- Diminished or absent breath sounds.
- See-saw breathing.
- Agitation or restlessness.
- Decreased levels of consciousness, disorientation, confusion.
- Inability to cough effectively.
Interventions
If airway issues have been found, then you cannot move on in the algorithm until these have been fixed. Often, some basic airway manoeuvres can help correct airway issues.
Head-tilt chin-lift, jaw thrust, oropharyngeal, nasopharyngeal, and supraglottic airways can be used to fix issues.
Ensure to reassess after any interventions.
B – Breathing
Assessment
Firstly, patient’s Respiration Rate should be recorded.
Typically, a normal respiratory rate falls within the range of 12-20 breaths per minute. In cases of pulmonary embolism (PE), tachypnoea may occur as a compensatory mechanism to address the ventilation-perfusion mismatch commonly associated with pulmonary embolisms (PE).
Secondly, Oxygen Saturation (SpO2) should be obtained.
In healthy individuals, a normal SpO2 range is 94-98%, while for patients with chronic obstructive pulmonary disease (COPD) who are prone to retaining CO2, the range is 88-92%. It is noteworthy that hypoxemia is a characteristic clinical feature observed in pulmonary embolism.
A full chest examination should be carried out, with particular attention to Auscultation and Percussion.
In pulmonary embolism, air entry is generally normal, but there may be a reduction in specific areas corresponding to infarcted lung tissue. The presence of coarse crackles or pleural rub during auscultation may indicate a pleural effusion resulting from infarcted lung tissue.
Percussion may identify regions of dullness that could be indicative of pleural effusion or lobar collapse secondary to infarcted lung tissue.
Interventions
Oxygen should be administered on all sick patients during initial assessment, regardless of oxygen saturations. This can then be titrated based on oxygen saturations. Read more about Oxygen here. Sitting the patient upright may help with oxygenation in addition to some relief from the chest pain if present.
Assisted Ventilations with a bag-valve-mask may be needed if respiration rate is below 10 or above 30 with altered conscious level. A ventilation rate of around 10-12 (one every 6 seconds) should be adopted.
If no breathing rate is present or agonal/ineffective breathing, then resuscitation should be started with Chest Compressions and additional help requested.
Ensure to reassess after any interventions.
C – Circulation
Assessment
A bilateral assessment of Pulse should be carried out.
Patients with pulmonary embolism (PE) may exhibit tachycardia, although many may maintain a normal pulse rate.
A Blood Pressure should be recorded.
Significant pain associated with PE may lead to hypertension. However, if hypotension is present may suggest cardiac failure secondary to right heart strain, which can be seen in cases of massive pulmonary embolisms.
A Capillary Refill Time (CRT) should be assessed next.
Capillary Refill Time (CRT) may appear normal or sluggish if hypovolemia is present.
Jugular Venous Pressure (JVP) & Juglar Vein Distension (JVD) should be recorded.
An elevated JVP or JVD in the context of PE may indicate underlying right heart strain which signifies the possibility of a massive pulmonary embolism.
An ECG should be recorded.
Some ECG findings can suggest the presence of pulmonary embolisms. Sinus tachycardia is the predominant ECG finding in pulmonary embolism (PE).
Additional ECG findings related to PE encompass:
Onset of atrial fibrillation
Right axis deviation
Right bundle branch block
T wave inversion
S1Q3T3 pattern: characterised by S waves in lead I, Q waves in lead III, and T wave inversion in lead III.
Interventions
At this stage a Two-Level Wells Score can be calculated.
The first scoring table assesses the likeliness of Deep Vein Thrombosis, which can often be the cause of pulmonary embolisms. If the score is < 2 it indicates DVT unlikely or if score is > 2 then DVT is likely. You can read more on DVT here.
The second scoring table assesses the likeliness of Pulmonary Embolisms although a CT pulmonary angiogram can only definitely diagnosis a PE. A score of 4 or less indicates PE unlikely. A score of more than 4 indicates PE likely.
Intravenous Cannulation
Whilst prophylactic cannulation is not commonly practice prehospitally due to the risk of infection, if patient appears to be unstable or drug interventions needed then access should be obtained, ideally with a large bore cannula.
Intravenous Fluids
Intravenous fluids may be needed if patients is hypovolaemia. Read the article on fluid resuscitation here.
Ensure to reassess after any interventions.
D – Disability
Assessment
Level Of Consciousness should be assessed (AVPU) and Glasgow Coma Scale (GCS)
Evaluate the patient’s consciousness level by employing the AVPU scale:
Alert: The patient is fully alert, though not necessarily oriented.
Verbal: The patient provides some form of response when spoken to (e.g., words, grunt).
Pain: The patient reacts to a painful stimulus (e.g., supraorbital pressure).
Unresponsive: The patient shows no evidence of eye, voice, or motor responses to pain.
Read here to find out how to record a GCS.
Assessment of pupils should be carried out.
Inspect the size, symmetry, and reactiveness of the pupils in both eyes.
Blood Glucose should be recorded.
A normal blood glucose level should be between 4.0 – 8.0 mmol/L.
Interventions
Airway may need to be maintained if patients’ consciousness level is reduced.
Ensure to reassess after any interventions.
E – Exposure
Assessment
Leg Inspection should be carried out.
Inspect lower legs for evidence of DVTs.
Temperature should be recorded.
An increase in temperature may be noted in pulmonary embolism as part of the catecholamine (stress) response.
Pain score should be recorded, and appropriate analgesia given.
Reassessment
Perform a thorough re-evaluation of the patient using the ABCDE approach to detect any alterations in their clinical status and evaluate the impact of your prior interventions.
Swift recognition of deterioration is crucial, and immediate action should be taken.
Transport To ED
Transportation to ED should be swift in cases of suspected pulmonary embolisms and conveyed under emergency conditions. The patient should not be encouraged to walk, and manual handling techniques should be adopted to transfer patient to the ambulance.
Pre-alert to the nearest ED department should also be implemented, using either the ATMIST or SBAR handover tools.
Alternative Diagnosis
Pulmonary embolisms can manifest with symptoms that overlap with various other medical conditions. Some potential differential diagnoses to consider include:
Pneumonia: Inflammation of the lung tissue, often accompanied by fever, cough, and difficulty breathing.
Myocardial Infarction (Heart Attack): Chest pain and shortness of breath may resemble symptoms of a pulmonary embolism.
Asthma: Wheezing and breathlessness can be similar to pulmonary embolism symptoms.
Chronic Obstructive Pulmonary Disease (COPD): Chronic lung conditions like emphysema or chronic bronchitis may present with respiratory symptoms.
Anxiety/Panic Attacks: Palpitations, chest tightness, and shortness of breath may be attributed to anxiety or panic disorders.
Costochondritis: Inflammation of the chest wall cartilage can cause chest pain, which may mimic pulmonary embolism symptoms.
Pericarditis: Inflammation of the lining around the heart, leading to chest pain and discomfort.
Pleurisy: Inflammation of the membranes surrounding the lungs, resulting in sharp chest pain exacerbated by breathing.
Pulmonary Hypertension: Elevated blood pressure in the pulmonary arteries may cause symptoms resembling those of pulmonary embolism.
Rib Fracture: Trauma to the chest, causing pain and difficulty breathing.
Conclusion
Pulmonary embolisms (PE) represent a significant medical emergency with potentially life-threatening consequences. Timely recognition and appropriate prehospital management are crucial in improving outcomes for individuals affected by this condition.
The diverse and often subtle symptoms of PE, ranging from dyspnoea and chest pain to syncope, require a high index of suspicion on the part of the prehospital clinical. Rapid intervention, including supplemental oxygen, intravenous access, and pain management, contributes to maintaining adequate oxygenation and addressing immediate patient needs.
Key Points
- Pulmonary embolism (PE) is a potentially life-threatening condition characterised by the obstruction of one or more pulmonary arteries by a blood clot (embolus).
- The presentation of PE can vary widely, ranging from asymptomatic cases to sudden-onset symptoms such as chest pain (often pleuritic), shortness of breath, rapid breathing, cough (may be bloody), rapid heart rate, fainting, sweating, and anxiety.
- Management of PE aims to prevent further clot propagation, reduce the risk of recurrence, and alleviate symptoms.
Bibliography
NHS . (2019). Pulmonary embolism. NHS. https://www.nhs.uk/conditions/pulmonary-embolism
NICE. (2020, October). Pulmonary Embolism. NICE. https://cks.nice.org.uk/topics/pulmonary-embolism
Swaroop, M., & Tarbox, A. (2013). Pulmonary embolism. International Journal of Critical Illness and Injury Science, 3(1), 69. https://doi.org/10.4103/2229-5151.109427