According to NICE 2017 guidelines, if a patient with asthma is not effectively managed with a SABA + ICS, the first step should be to add a LTRA rather than a LABA.

The management of asthma in adults has been updated by NICE in 2017, following the 2016 BTS guidelines. One of the significant changes is in ‘step 3’, where patients on a SABA + ICS whose asthma is not well controlled should be offered a leukotriene receptor antagonist instead of a LABA. NICE does not follow the stepwise approach of the previous BTS guidelines, but to make the guidelines easier to follow, we have added our own steps. The steps range from newly-diagnosed asthma to SABA +/- LTRA + one of the following options, including increasing ICS to high-dose, a trial of an additional drug, or seeking advice from a healthcare professional with expertise in asthma. Maintenance and reliever therapy (MART) is a form of combined ICS and LABA treatment that is only available for ICS and LABA combinations in which the LABA has a fast-acting component. It should be noted that NICE does not recommend changing treatment in patients who have well-controlled asthma simply to adhere to the latest guidance. The definitions of what constitutes a low, moderate, or high-dose ICS have also changed, with <= 400 micrograms budesonide or equivalent being a low dose, 400 micrograms - 800 micrograms budesonide or equivalent being a moderate dose, and > 800 micrograms budesonide or equivalent being a high dose for adults.

Klebsiella pneumoniae is a gram-negative rod that commonly causes a cavitating pneumonia in the upper lobes, particularly in individuals with a history of diabetes and alcoholism. The presence of upper zone crackles is a sign of Klebsiella pneumoniae infection, while a history of alcoholic pancreatitis suggests chronic alcohol use.

Legionella pneumophila causes Legionnaire’s disease, an atypical pneumonia that typically spreads through contaminated water sources, such as air conditioner vents. Symptoms include fever, cough, and myalgia, with bilateral chest symptoms being more common. Other extra-pulmonary symptoms, such as hyponatremia and hepatitis, may also be present.

Mycoplasma pneumoniae is another cause of atypical pneumonia, with symptoms including coryza and a dry cough. This form of pneumonia is associated with extra-pulmonary symptoms such as haemolytic anaemia and erythema multiforme, which are not present in this case.

Staphylococcus aureus is the most likely cause of pneumonia following influenza virus infection. However, since there is no history of preceding coryza and the patient has upper zone crackles and alcoholism, Staphylococcus aureus is less likely to be the cause of this patient’s pneumonia.

Klebsiella Pneumoniae: A Gram-Negative Rod Causing Infections in Humans

Klebsiella pneumoniae is a type of Gram-negative rod that is typically found in the gut flora of humans. Although it is a normal part of the body’s microbiome, it can also cause a variety of infections in humans, including pneumonia and urinary tract infections. This bacterium is more commonly found in individuals who have diabetes or who consume alcohol regularly. In some cases, Klebsiella pneumoniae infections can occur following aspiration.

One of the distinctive features of Klebsiella pneumoniae infections is the presence of red-currant jelly sputum. This type of sputum is often seen in patients with pneumonia caused by this bacterium. Additionally, Klebsiella pneumoniae infections tend to affect the upper lobes of the lungs.

Unfortunately, Klebsiella pneumoniae infections can be quite serious and even life-threatening. They commonly lead to the formation of lung abscesses and empyema, and the mortality rate for these infections is between 30-50%. It is important for healthcare providers to be aware of the potential for Klebsiella pneumoniae infections, particularly in patients who are at higher risk due to underlying health conditions.

An anion gap greater than 14 mmol/L typically indicates a raised anion gap metabolic acidosis, rather than a normal anion gap. In the absence of other information about the patient, an arterial blood gas (ABG) can provide a clue to the diagnosis. In this case, the ABG shows a normal paO2, indicating a respiratory cause of the patient’s symptoms is less likely. However, the pH is below 7.35, indicating acidosis, and the bicarbonate is low, suggesting metabolic acidosis. The low paCO2 shows partial compensation. Calculating the anion gap reveals a value of 31 mmol/L, indicating metabolic acidosis with a raised anion gap. Septic shock is the only listed cause of raised anion gap metabolic acidosis, resulting in acidosis due to the production of lactic acid from inadequate tissue perfusion. Addison’s disease is another cause of metabolic acidosis, but it results in normal anion gap metabolic acidosis due to bicarbonate loss from mineralocorticoid deficiency. Prolonged diarrhea can cause normal anion gap metabolic acidosis due to gastrointestinal loss of bicarbonate. Pulmonary embolism is unlikely due to normal oxygen levels and hypocapnia occurring as compensation. Prolonged vomiting can cause metabolic alkalosis, not metabolic acidosis, due to the loss of hydrogen ions in vomit. This patient’s electrolyte profile does not fit with prolonged vomiting.

The anion gap is a measure of the difference between positively charged ions (sodium and potassium) and negatively charged ions (bicarbonate and chloride) in the blood. It is calculated by subtracting the sum of bicarbonate and chloride from the sum of sodium and potassium. A normal anion gap falls between 8-14 mmol/L. This measurement is particularly useful in diagnosing metabolic acidosis in patients.

There are various causes of a normal anion gap or hyperchloraemic metabolic acidosis. These include gastrointestinal bicarbonate loss due to conditions such as diarrhoea, ureterosigmoidostomy, or fistula. Renal tubular acidosis, drugs like acetazolamide, ammonium chloride injection, and Addison’s disease can also lead to a normal anion gap.

On the other hand, a raised anion gap metabolic acidosis can be caused by lactate due to shock or hypoxia, ketones in conditions like diabetic ketoacidosis or alcoholism, urate in renal failure, acid poisoning from substances like salicylates or methanol, and 5-oxoproline from chronic paracetamol use. Understanding the anion gap and its potential causes can aid in the diagnosis and treatment of metabolic acidosis.

The recommended initial investigation for suspected occupational asthma is serial peak expiratory flow rates at home and at work, according to SIGN (Scottish Intercollegiate Guidelines Network) referenced by NICE. CT of the thorax is inappropriate due to high radiation doses and chest radiograph is not part of the initial work-up for occupational asthma as it is unlikely to show specific evidence. Skin-prick testing is only recommended for high-molecular-weight agents and spirometry is not recommended as an initial investigation for occupational asthma, but may be appropriate for surveillance in industries with risk of the condition.

According to NICE (2017) guidelines, patients with asthma should be prescribed a SABA as the first step of treatment. However, if a patient experiences symptoms three or more times per week or night waking, they should also be prescribed a low-dose ICS inhaler as the second step of treatment. This is also necessary for patients who have had an acute exacerbation requiring oral corticosteroids in the past two years. In this case, the patient’s symptoms are not well-controlled with a SABA alone, and she experiences frequent symptoms and night waking. Therefore, she requires a low-dose ICS inhaler, and the only option available is budesonide.

Adding a salmeterol inhaler is not appropriate at this stage, as LABAs are only used as the fourth step of treatment if a patient is not controlled with a SABA, low-dose ICS, and a trial of LTRAs. Similarly, adding montelukast and a beclomethasone inhaler is not appropriate, as LTRAs are only added if a patient is still not controlled on a low-dose ICS and a SABA. However, it may be appropriate to trial beclomethasone without montelukast.

Continuing with the current salbutamol-only treatment is not appropriate, as the patient’s asthma is poorly controlled, which increases the risk of morbidity and mortality. Regular salbutamol has no role in the management of asthma, as it does not improve outcomes and may even worsen them by downregulating beta receptors that are important for bronchodilation.

The management of asthma in adults has been updated by NICE in 2017, following the 2016 BTS guidelines. One of the significant changes is in ‘step 3’, where patients on a SABA + ICS whose asthma is not well controlled should be offered a leukotriene receptor antagonist instead of a LABA. NICE does not follow the stepwise approach of the previous BTS guidelines, but to make the guidelines easier to follow, we have added our own steps. The steps range from newly-diagnosed asthma to SABA +/- LTRA + one of the following options, including increasing ICS to high-dose, a trial of an additional drug, or seeking advice from a healthcare professional with expertise in asthma. Maintenance and reliever therapy (MART) is a form of combined ICS and LABA treatment that is only available for ICS and LABA combinations in which the LABA has a fast-acting component. It should be noted that NICE does not recommend changing treatment in patients who have well-controlled asthma simply to adhere to the latest guidance. The definitions of what constitutes a low, moderate, or high-dose ICS have also changed, with <= 400 micrograms budesonide or equivalent being a low dose, 400 micrograms - 800 micrograms budesonide or equivalent being a moderate dose, and > 800 micrograms budesonide or equivalent being a high dose for adults.

Paraneoplastic syndromes are a group of disorders that can occur in patients with certain types of cancer, but are not caused by metastases, infections, metabolic disorders, chemotherapy, or coagulation disorders. These syndromes can present with a variety of symptoms affecting different body systems. Some of these syndromes are specific to certain types of cancer and may be the first sign of the disease. Therefore, if a patient presents with symptoms of a paraneoplastic syndrome, it is important to consider the possibility of an underlying malignancy. While certain paraneoplastic syndromes are associated with specific types of cancer, there can be some overlap.

The most likely diagnosis for this patient is lung abscess, as they are presenting with a subacute productive cough, foul-smelling sputum, and night sweats. The duration of a cough can be categorized as acute, subacute, or chronic, and this patient falls under the subacute category. The patient’s recent history of aspiration pneumonia and examination findings, such as dullness on percussion, bronchial breath sounds, and fever, support the diagnosis of lung abscess.

Lung cancer is not the most likely diagnosis for this patient, as they do not have weight loss and have other findings that point towards lung abscess. Pulmonary fibrosis is also unlikely, as it is rare to have unilateral pulmonary fibrosis, and the patient’s examination findings do not support this diagnosis. Recurrent pneumonia is a good differential, but the presence of bronchial breath sounds and night sweats make lung abscess a more likely diagnosis.

Understanding Lung Abscess

A lung abscess is a localized infection that occurs within the lung tissue. It is commonly caused by aspiration pneumonia, which can be triggered by poor dental hygiene, reduced consciousness, or previous stroke. Other potential causes include haematogenous spread, direct extension, and bronchial obstruction. The infection is typically polymicrobial, with Staphylococcus aureus, Klebsiella pneumonia, and Pseudomonas aeruginosa being the most common monomicrobial causes.

The symptoms of lung abscess are similar to pneumonia, but they tend to develop more slowly over several weeks. Patients may experience fever, productive cough, foul-smelling sputum, chest pain, and dyspnea. Some may also have systemic features such as night sweats and weight loss, while a minority may experience haemoptysis. Physical examination may reveal dull percussion and bronchial breathing, as well as clubbing in some cases.

To diagnose lung abscess, a chest x-ray is usually performed, which shows a fluid-filled space within an area of consolidation. Sputum and blood cultures should also be obtained to identify the causative organism. Treatment typically involves intravenous antibiotics, but if the infection does not resolve, percutaneous drainage or surgical resection may be required in rare cases.

The patient’s history, examination, and obstructive spirometry results suggest that he has COPD, likely due to his smoking history. Malignancy has been ruled out by the chest x-ray. As per NICE guidelines, the first-line pharmacological treatment for COPD is either a SABA or SAMA to alleviate breathlessness and improve exercise tolerance. Ipratropium, a SAMA, is the most suitable option for this patient. Beclomethasone, an inhaled corticosteroid, is used as a second-line treatment with a LABA for those with asthmatic features or steroid responsiveness. Montelukast, a LTRA, is used as a third-line treatment in asthmatic patients, while Salmeterol, a LABA, is used as a second-line treatment in COPD patients.

NICE guidelines recommend smoking cessation advice, annual influenza and one-off pneumococcal vaccinations, and pulmonary rehabilitation for COPD patients. Bronchodilator therapy is first-line treatment, with the addition of LABA and LAMA for patients without asthmatic features and LABA, ICS, and LAMA for those with asthmatic features. Theophylline is recommended after trials of bronchodilators or for patients who cannot use inhaled therapy. Azithromycin prophylaxis is recommended in select patients. Mucolytics should be considered for patients with a chronic productive cough. Loop diuretics and long-term oxygen therapy may be used for cor pulmonale. Smoking cessation and long-term oxygen therapy may improve survival in stable COPD patients. Lung volume reduction surgery may be considered in selected patients.

The recommended first-line antibiotic for patients with low severity community-acquired pneumonia (CAP) is oral amoxicillin. Therefore, it is appropriate to discharge this patient with oral amoxicillin as they present with symptoms of CAP, including a new cough, temperature, purulent sputum, and focal chest signs. While a chest x-ray could confirm the diagnosis, it is not usually necessary for suspected CAP managed in primary care. The patient’s CRB-65 score is 0, indicating that they can be managed in the community. Hospitalization may be required for patients with higher scores or clinical factors that increase the risk of complications, but this is not the case for this patient. Discharge with oral clarithromycin or doxycycline is not appropriate as there is no indication that amoxicillin is unsuitable as the first-line antibiotic.

Pneumonia is a serious respiratory infection that requires prompt assessment and management. In the primary care setting, the CRB65 criteria are used to stratify patients based on their risk of mortality. Patients with a score of 0 are considered low risk and may be treated at home, while those with a score of 3 or 4 are high risk and require urgent admission to hospital. The use of a point-of-care CRP test can help guide antibiotic therapy. In the secondary care setting, the CURB65 criteria are used, which includes an additional criterion of urea > 7 mmol/L. Chest x-rays and blood and sputum cultures are recommended for intermediate or high-risk patients. Treatment for low-severity community acquired pneumonia typically involves a 5-day course of amoxicillin, while moderate and high-severity cases may require dual antibiotic therapy for 7-10 days. Discharge criteria and advice post-discharge are also provided, including information on expected symptom resolution timeframes and the need for a repeat chest x-ray at 6 weeks.

The treatment of tuberculosis is a complex process that requires the expertise of a specialist in the field, such as a respiratory physician or an infectivologist. The first-line drugs used for active tuberculosis without CNS involvement are isoniazid, rifampicin, pyrazinamide, and ethambutol. These drugs are given together for the first 2 months of therapy, followed by continued treatment with just isoniazid and rifampicin for an additional 4 months. Pyridoxine is added to the treatment regimen to reduce the risk of isoniazid-induced peripheral neuropathy. If there is CNS involvement, the four drugs (and pyridoxine) are given together for 2 months, followed by continued treatment with isoniazid (with pyridoxine) and rifampicin for an additional 10 months. It is important to monitor liver function tests before and during treatment, and to educate patients on the potential side effects of the drugs and when to seek medical attention. Treatment-resistant tuberculosis cases are becoming more common and require special management and public health considerations.

Understanding Myasthenia Gravis: Symptoms, Diagnosis, and Treatment

Myasthenia gravis (MG) is a neuromuscular disorder that occurs when the body produces autoantibodies against the nicotinic acetylcholine receptor at the neuromuscular junction. This results in muscular weakness that is characterized by fatigability, meaning that the muscles become increasingly weaker during their use. MG primarily affects the muscles of the face, the extrinsic ocular muscles (causing diplopia), and the muscles involved in deglutition. Respiratory and proximal lower limb muscles may also be involved early in the disease, which can cause breathlessness and even sudden death.

Diagnosing MG can be challenging, as weakness may not be apparent on a single examination. However, electrodiagnostic tests and detecting the autoantibodies can confirm the diagnosis. The Tensilon test, which involves injecting edrophonium chloride to reverse the symptoms of MG, is now used only when other tests are negative and clinical suspicion of MG is still high.

Treatment of MG involves anticholinesterase medications, but many patients also benefit from thymectomy. It is important to note that a thymoma may be present in up to 15% of patients with MG.

Other conditions, such as transient ischaemic attacks, angina, multiple sclerosis, and somatisation disorder, may cause weakness, but they do not typically present with the same symptoms as MG. Therefore, it is crucial to consider MG as a potential diagnosis when a patient presents with fatigable muscular weakness.

The recommended initial management for patients with suspected pulmonary embolism (PE) is to ensure they are haemodynamically stable before starting anticoagulation. According to the latest NICE Guidelines (2020), a direct oral anticoagulant (DOAC) such as apixaban or rivaroxaban should be started unless there are contraindications. In this case, the patient is stable and can be started on rivaroxaban. It is important to note that starting prophylactic dose LMWH is not appropriate for suspected PE, and commencing warfarin at loading dose is also not recommended due to its delayed anticoagulant effects. Thrombolytic agents such as alteplase are only appropriate for haemodynamically unstable patients. Dabigatran is an alternative option for patients who cannot take apixaban or rivaroxaban, but it too requires a bridging dose of LMWH.

Management of Pulmonary Embolism: NICE Guidelines

Pulmonary embolism (PE) is a serious condition that requires prompt management. The National Institute for Health and Care Excellence (NICE) updated their guidelines on the management of venous thromboembolism (VTE) in 2020, with some key changes. One of the significant changes is the recommendation to use direct oral anticoagulants (DOACs) as the first-line treatment for most people with VTE, including those with active cancer. Another change is the increasing use of outpatient treatment for low-risk PE patients, determined by a validated risk stratification tool.

Anticoagulant therapy is the cornerstone of VTE management, and the guidelines recommend using apixaban or rivaroxaban as the first-line treatment following the diagnosis of a PE. If neither of these is suitable, LMWH followed by dabigatran or edoxaban or LMWH followed by a vitamin K antagonist (VKA) can be used. For patients with active cancer, DOACs are now recommended instead of LMWH. The length of anticoagulation is determined by whether the VTE was provoked or unprovoked, with treatment typically stopped after 3-6 months for provoked VTE and continued for up to 6 months for unprovoked VTE.

In cases of haemodynamic instability, thrombolysis is recommended as the first-line treatment for massive PE with circulatory failure. Patients who have repeat pulmonary embolisms, despite adequate anticoagulation, may be considered for inferior vena cava (IVC) filters. However, the evidence base for IVC filter use is weak.

Overall, the updated NICE guidelines provide clear recommendations for the management of PE, including the use of DOACs as first-line treatment and outpatient management for low-risk patients. The guidelines also emphasize the importance of individualized treatment based on risk stratification and balancing the risks of VTE recurrence and bleeding.

Understanding PEFR and Its Role in Diagnosing Asthma

Peak expiratory flow rate (PEFR) is a valuable tool in both the diagnosis and management of asthma. It is measured by a maximal forced expiration through a peak-flow meter and correlates well with forced expiratory volume in one second (FEV1), providing an estimate of airway calibre. Patients with asthma can monitor their PEFR at home to track disease control. A PEFR <80% of predicted is a strong indicator of obstructive airway disease, such as asthma. However, it’s important to note that PEFR is not affected by restrictive defects, such as those caused by kyphoscoliosis. Bronchial carcinoma itself does not cause airflow limitation, but a co-morbid obstructive lung disease, such as asthma or COPD, could produce abnormal PEFR readings. Bronchiectasis can cause an obstructive pattern on spirometry, but it would not typically cause a reduction in PEFR. Whooping cough, despite causing inflammation of the airways, would not typically result in the markedly reduced PEFR readings seen in asthma. In conclusion, understanding PEFR and its role in diagnosing asthma is crucial for both patients and healthcare providers. By monitoring PEFR at home and seeking medical attention when necessary, individuals with asthma can better manage their condition and improve their quality of life.

The 2015 Resus Council guidelines for adult advanced life support outline the steps to be taken when dealing with patients with shockable and non-shockable rhythms. For both types of patients, chest compressions are a crucial part of the process, with a ratio of 30 compressions to 2 ventilations. Defibrillation is recommended for shockable rhythms, with a single shock for VF/pulseless VT followed by 2 minutes of CPR. Adrenaline and amiodarone are the drugs of choice for non-shockable rhythms, with adrenaline given as soon as possible and amiodarone administered after 3 shocks for VF/pulseless VT. Thrombolytic drugs should be considered if a pulmonary embolus is suspected. Atropine is no longer recommended for routine use in asystole or PEA. Oxygen should be titrated to achieve saturations of 94-98% following successful resuscitation. The Hs and Ts should be considered as potential reversible causes of cardiac arrest.

Angiotensin II receptor blockers may be considered for hypertension patients who experience cough as a side effect of ACE inhibitors. This is especially relevant for elderly patients, as ACE inhibitors or angiotensin II receptor blockers are the preferred initial treatment options for hypertension.

Angiotensin II receptor blockers are a type of medication that is commonly used when patients cannot tolerate ACE inhibitors due to the development of a cough. Examples of these blockers include candesartan, losartan, and irbesartan. However, caution should be exercised when using them in patients with renovascular disease. Side-effects may include hypotension and hyperkalaemia.

The mechanism of action for angiotensin II receptor blockers is to block the effects of angiotensin II at the AT1 receptor. These blockers have been shown to reduce the progression of renal disease in patients with diabetic nephropathy. Additionally, there is evidence to suggest that losartan can reduce the mortality rates associated with CVA and IHD in hypertensive patients.

Overall, angiotensin II receptor blockers are a viable alternative to ACE inhibitors for patients who cannot tolerate the latter. They have a proven track record of reducing the progression of renal disease and improving mortality rates in hypertensive patients. However, as with any medication, caution should be exercised when using them in patients with certain medical conditions.

Understanding Metabolic Acidosis and Anion Gap

Metabolic acidosis is a condition that occurs when the body produces too much acid or when the kidneys are not able to remove enough acid from the body. It is commonly classified according to the anion gap, which can be calculated by subtracting the sum of chloride and bicarbonate levels from the sum of sodium and potassium levels. The normal range for anion gap is 10-18 mmol/L. If a question supplies the chloride level, it may be a clue that the anion gap should be calculated.

There are two types of metabolic acidosis based on anion gap levels. Normal anion gap or hyperchloraemic metabolic acidosis is caused by gastrointestinal bicarbonate loss, prolonged diarrhea, ureterosigmoidostomy, fistula, renal tubular acidosis, drugs, ammonium chloride injection, and Addison’s disease. On the other hand, raised anion gap is caused by lactate, ketones, urate, acid poisoning, and other factors.

Metabolic acidosis secondary to high lactate levels may be subdivided into two types: lactic acidosis type A and lactic acidosis type B. Lactic acidosis type A is caused by sepsis, shock, hypoxia, and burns, while lactic acidosis type B is caused by metformin. Understanding the different types of metabolic acidosis and anion gap levels can help in diagnosing and treating the condition.

Once the predicted values are obtained, the FEV1:FVC ratio can be evaluated. If this ratio is less than 70, it indicates a potential issue.

Understanding Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic lung condition that causes progressive fibrosis of the interstitium of the lungs. Unlike other causes of lung fibrosis, IPF has no underlying cause. It is typically seen in patients aged 50-70 years and is more common in men.

The symptoms of IPF include progressive exertional dyspnoea, dry cough, clubbing, and bibasal fine end-inspiratory crepitations on auscultation. Diagnosis is made through spirometry, impaired gas exchange tests, and imaging such as chest x-rays and high-resolution CT scans.

Management of IPF includes pulmonary rehabilitation, but very few medications have been shown to be effective. Some evidence suggests that pirfenidone, an antifibrotic agent, may be useful in selected patients. Many patients will eventually require supplementary oxygen and a lung transplant.

The prognosis for IPF is poor, with an average life expectancy of around 3-4 years. CT scans can show advanced pulmonary fibrosis, including honeycombing. While there is no cure for IPF, early diagnosis and management can help improve quality of life and potentially prolong survival.

Dealing with Choking Emergencies

Choking is a serious medical emergency that can be life-threatening. It occurs when the airway is partially or completely blocked, often while eating. The first step in dealing with a choking victim is to ask them if they are choking. If they are able to speak and breathe, it may be a mild obstruction. However, if they are unable to speak or breathe, it is a severe obstruction and requires immediate action.

According to the Resus Council, mild airway obstruction can be treated by encouraging the patient to cough. However, if the obstruction is severe and the patient is conscious, up to five back-blows and abdominal thrusts can be given. If these methods are unsuccessful, the cycle should be repeated. If the patient is unconscious, an ambulance should be called and CPR should be started.

It is important to note that choking can happen to anyone, so it is important to be prepared and know how to respond in an emergency. By following these steps, you can help save a life.

Identifying the Probable Cause of Pulmonary Fibrosis

Methotrexate is the correct answer as it is a well-known drug-related cause of pulmonary fibrosis, which is the probable cause of the patient’s symptoms. Hydroxychloroquine, azathioprine, ciclosporin, and penicillamine are not known to cause pulmonary fibrosis, although some of them have the potential to cause pneumonitis. Ciclosporin has been studied as a treatment for the disease, but it is not recommended by NICE. Therefore, it is important to identify the probable cause of pulmonary fibrosis to provide appropriate treatment and prevent further complications.

Understanding the Two-Level PE Wells Score: Clinical Signs and Symptoms of DVT

The Two-Level PE Wells Score is a tool used to assess the likelihood of a patient having a pulmonary embolism (PE). One of the key factors in this score is the presence of clinical signs and symptoms of a deep-vein thrombosis (DVT), which includes leg swelling and pain on palpation of the deep veins. This carries three points in the score, and is a crucial factor in determining the likelihood of a PE.

Other factors in the score include an alternative diagnosis being less likely than a PE, heart rate over 100 beats/min, immobilization or recent surgery, previous DVT/PE, haemoptysis, and malignancy. Each of these factors carries a certain number of points, and a score of over 4 points indicates a high likelihood of a PE, while a score of 4 points or less indicates a lower likelihood.

Overall, understanding the Two-Level PE Wells Score and the clinical signs and symptoms of DVT is important in accurately assessing the likelihood of a patient having a PE and determining the appropriate course of treatment.