Pulmonary embolism  

Diagnosis  

Diagnosing a pulmonary embolism can pose challenges, particularly in the presence of underlying heart or lung conditions. Consequently, healthcare professionals typically engage in discussions regarding medical history, conduct physical examinations, and request tests that may include the options listed below. 

• Blood tests: A blood test may be ordered by a healthcare provider to assess the clot–dissolving substance D dimer, where elevated levels could indicate a higher propensity for blood clots, despite various other factors possibly contributing to such levels. These tests also enable the measurement of blood oxygen and carbon dioxide quantities, with a lung blood vessel clot potentially leading to diminished oxygen levels. Furthermore, blood tests might be conducted to identify the presence of an inherited clotting disorder. 
• Chest X–ray: This noninvasive test captures images of the heart and lungs on film. While X–rays are unable to diagnose a pulmonary embolism and might even appear normal despite its presence, they can eliminate other conditions presenting similar symptoms. 
• Ultrasound: A noninvasive test referred to as duplex ultrasonography, also known as a duplex scan or compression ultrasonography, employs sound waves to scan veins and identify deep vein blood clots. This examination covers veins in the thigh, knee, calf, and occasionally the arms. Using a wand–shaped device called a transducer, which is placed on the skin, sound waves are directed towards the targeted veins. These waves bounce back to the transducer, forming a dynamic image on a computer screen. The absence of clots reduces the likelihood of deep vein thrombosis, while the presence of clots often necessitates immediate treatment. 
• Computed tomography (CT) pulmonary angiography: CT scanning employs X–rays to generate cross–sectional body images. CT pulmonary angiography, also known as a CT pulmonary embolism study, produces 3D images capable of detecting modifications like a pulmonary embolism within the lung arteries. Occasionally, contrast material is introduced via a hand or arm vein during the CT scan to highlight the pulmonary arteries. 
• Ventilation–perfusion (V/Q) scan: In cases where radiation or contrast exposure from a CT scan must be avoided due to a medical condition, a V/Q scan might be performed. During this examination, a trace amount of a radioactive substance, known as a tracer, is injected into a vein in your arm. The tracer maps the blood flow, referred to as perfusion, and contrasts it with lung airflow, known as ventilation. This test helps ascertain if blood clots are responsible for symptoms of pulmonary hypertension. 

• Pulmonary angiogram: This test offers a clear depiction of blood flow within the lung arteries, serving as the most accurate method to diagnose a pulmonary embolism. However, due to the need for advanced expertise and the potential for serious risks, it’s usually reserved for situations where other tests fall short in providing a definitive diagnosis. During a pulmonary angiogram, a slender and flexible catheter tube is inserted into a larger vein, typically in the groin, and is threaded through the heart and into the pulmonary arteries. Subsequently, a special dye is introduced through the catheter, with X–rays capturing its progression along the lung arteries. Some individuals may experience a transient alteration in heart rhythm due to this procedure, and there’s also an elevated risk of kidney damage from the dye, particularly among those with impaired kidney function. 
• Magnetic Resonance Imaging (MRI): MRI is a medical imaging technique that employs a magnetic field and computer–generated radio waves to generate detailed images of the organs and tissues within your body. MRI is typically conducted exclusively for individuals who are pregnant, aiming to circumvent radiation exposure to the fetus, and for individuals whose kidneys could potentially be adversely affected by the dyes utilized in other diagnostic tests. 

Treatment   

The treatment approach for a pulmonary embolism focuses on preventing the blood clot from growing larger and stopping the formation of new clots. Swift treatment is crucial to avoid severe complications or potential fatality. The treatment regimen includes medication, surgical interventions, and ongoing medical attention.  

• Medications: The medication options comprise various types of blood thinners and clot–dissolving agents. Medicines include: 
• Blood Thinners: These anticoagulant medications impede the enlargement of existing clots and the development of fresh clots, allowing the body time to break down the clots naturally. Heparin, an anticoagulant, is often administered intravenously or subcutaneously for quick action. It is commonly used alongside an oral anticoagulant like warfarin until the oral medication becomes effective, which may take a few days. Modern oral anticoagulants work faster and have fewer interactions with other drugs. Some can be taken orally from the outset, eliminating the need for heparin. Nevertheless, all anticoagulants carry the potential for side effects, with bleeding being the most prevalent. 

• Clot Dissolvers: While clots typically dissolve naturally, thrombolytics—medications designed to dissolve clots—can be administered intravenously to expedite clot dissolution. Due to their potential to trigger sudden and severe bleeding, these clot–dissolving drugs are typically reserved for life–threatening situations. 

• Surgical and Procedural Interventions: 
• Clot Removal: In cases of large, life–threatening lung clots, a healthcare provider might employ a thin, flexible catheter threaded through blood vessels to eliminate the clot. 
• Vein Filter: A catheter can also be utilized to position a filter within the body’s main vein, the inferior vena cava, which connects the legs to the heart’s right side. This filter aids in preventing clots from reaching the lungs. This procedure is generally reserved for individuals who cannot tolerate anticoagulant medications or for those who continue to experience blood clots despite anticoagulant use. Some filters can be removed once they are no longer needed.
• Continued Care: Since there is a potential risk of recurrent deep vein thrombosis or pulmonary embolism, ongoing treatment is essential. This involves maintaining anticoagulant therapy and adhering to the monitoring schedule recommended by the healthcare provider. Regular appointments with the healthcare provider are crucial to preventing or managing any complications.