Pulmonary Embolism

When an artery in the lungs gets blocked, it is referred to as a medical condition of Pulmonary embolism. This condition can be life threatening. Often deep vein thrombosis (DVT) can lead to pulmonary embolism. The blood clots may originate in any other part of the body such as the arm, pelvis or legs. These clots travel through the bloodstream and enter the pulmonary arteries. Recent surgery or injury can lead to a blood clots. Persons with heart disease or those on estrogen therapy are at increased risk of pulmonary embolism. Typical symptoms experienced by those suffering from pulmonary embolism are chest pain, sudden shortness of breath and rapid heartbeat. A patient might have wheezing and weak pulse. The symptoms of pulmonary embolism depend on the extent and size of clots. Embolus can also be the result of fat from the bone marrow that has escaped into the bloodstream. It can also occur due to air bubbles formed during intravenous infusion or surgery. While large emboli cause considerable distress such as chest pain, smaller ones cause shortness of breath. Patients suffering from pulmonary embolism tend to have cough that produces sputum. There may be bluish discoloration on the skin and pain in the legs. Fainting spells or seizures might occur due to sudden decrease in oxygen-rich blood to the brain and other organs. Bluish tint on the skin (cyanosis) is observed when one or more large pulmonary arteries are obstructed.

Diagnostic procedures to detect pulmonary embolism:

• Chest X-ray helps in identifying any lung infections
  
• CAT scan
  
• ECG
  
• Perfusion Scan of the lung - This test helps in outlining the blood flow to the lungs and helps in detecting any obstructions.
• V/Q scan involves a a nuclear ventilation-perfusion study of the lungs.
  
• Pulmonary angiogram involves injection of a special dye into the pulmonary arteries to detect obstructive clots.
  
• D-dimer test is a test that spots d-dimer molecules released by the clots.
  

One of the initial steps to help a person suffering from pulmonary embolism is administration of oxygen and analgesics. Oxygen is administered through a nasal cannulae or face mask. Blood clots are treated with anticoagulant drugs like heparin or warfarin. But the duration and dosage of anticoagulants needs to be monitored so that it does not result in bleeding in other body organs. Thrombolysis is a procedure whereby Thrombolytic agents (clot-dissolving agents) are injected into the bloodstream to dissolve existing blood clots. Surgery (Pulmonary embolectomy) is often resorted to for removal of clots.

Pulmonary Infarction

Infarction means 'tissue death' in medical terminology. It is caused by obstruction of blood supply to the tissue leading to lack of oxygen. Infarct, which refers to the resulting lesion is derived from Latin, 'infarctus' which means 'stuffed into'. Pulmonary infarction refers to the death of a small area of lung resulting from pulmonary embolism. It occurs in a small, dead end pulmonary artery.

How does pulmonary infarction occur ?

Pulmonary infarction results from free floating thrombus, when many material substances including fat, tumor, septic emboli, air, and amniotic fluid and injected foreign material may form an emboli and move to the pulmonary circulation. In other words, plugging of a branch of the pulmonary artery by a clot (thrombosis) or by a piece of clot carried by the blood stream to the lung from a thrombus located elsewhere can result in pulmonary infarction. The involved area of the lung ceases to function and complication of the thrombosed veins leads to heart disease.

Causes of pulmonary infarction

The most common cause of pulmonary infarction is pulmonary embolism, but there are other conditions which can cause pulmonary infarction including cancer, and autoimmune diseases such as lupus. Sometimes, this condition may occur following a surgery. Other underlying conditions especially in children with pulmonary emboli include sickle cell disease, nephrotic syndrome, chemotherapy and Inherited hyper coagulable state and Vasculitis.

Symptoms of pulmonary infarction

Symptoms associated with pulmonary infarction include shortness of breath, chest pain, and blood sputum or hemoptysis. Sudden piercing pain in the chest which often radiates to the shoulder is noticed. Difficulty in breathing, irritating cough and blood tinged sputum are other signs. Persistent hiccups are present. Most often the patient is anxious with a rapid pulse, sweats profusely and has an elevated body temperature. In some severe cases, the patient may be in a state of shock.

Diagnosis of pulmonary infarction

Reflex broncho constriction is often associated with pulmonary embolism. Increased breathing and decreased pulmonary compliance with diminished surfactant levels may occur due to pulmonary infarction. This contributes to increased work of breathing and diminished oxygen levels. In sickle cell disease, there is sickling of RBCs within the small blood vessels of the lungs due to dehydration as a result of fever, Tachypnea (rapid breathing) and decreased intake, which can precipitate in a cycle of relative de oxygenation that further exacerbates the sickling tendency. Many also suffer a component of reactive airway disease and oxygenation is further decreased due to this factor.

Morbidity may include pulmonary hypertension, right ventricular failure and Cor Pulmonale, paradoxical embolization in patients with intracardiac defects, and sometimes side effects of medications used to treat pulmonary embolism. If pulmonary embolism is large, there could develop right ventricular strain and right heart failure as there is sudden increase in pulmonary artery pressure leading to right heart failure. A sudden pressure in the right ventricle can cause a leftward shift of the intraventricular septum, which may result in a classic obstructive shock, thereby impairing left ventricular filling.

Treating pulmonary infarction

It is timely treatment that is vital. If symptoms of pulmonary infection develop while at home, consult a physician at once. In case, shock develops, it is essential to get first aid treatment. Many times, patients are already in the hospital when pulmonary infarction occurs. Administration of oxygen, use of anticoagulants and prevention of infection are some other suggested line of treatment. Surgery may also be indicated.

Dyspnea

Dyspnea is commonly known as breathing difficulty or shortness of breath. It is noticed as difficulty in breathing or labored breathing. Tachypnea refers to rapid breathing. Progressively it can lead to hyperventilation such as experienced during an anxiety attack. Studies indicate that the origin of dyspnea is initiated with inaccurate central nervous system to the lungs with respect to breathing.

The etiology of dyspnea is related to conditions such as Pulmonary Embolism (PE), asthma, COPD, pulmonary ischemia and pneumonia. The management of dyspnea is only effective when the underlying causes are treated. In case of trauma, pneumothorax is an acute trigger for initiating the onset of dyspnea and hence emergency care is given to prevent internal bleeding that is caused in the pneumothorax. This condition can also progress into tachypnea and varied lung and heart sounds which has to be managed with effective ER procedures.

Positional dyspnea: If a person suffers dyspnea when lying down, it might be suggestive of CHF or pericardial effusion.

Exertional dyspnea: This occurs when there is reduction in oxygen supply and is mostly noticed in patients suffering cardiac disease or anemia.

Transient dyspnea: This situation usually resolves without medical intervention and is triggered by reversible causes such as panic attacks.

Recurrent dyspnea: Here the patient suffers these episodes many times.

Conditions such as pulmonary embolism can also lead to dyspnea along with tachycardia and diminished breathing patterns. Dyspnea is an immediate progressive condition usually associated with previous history of trauma or illness such as Tuberculosis, bronchopneumonia, infectious mononucleosis and sepsis in certain scenarios. Since dyspnea is an associated condition and it is predominantly an upper airway obstruction, the treatment measures are often related to avoiding exposure to chemicals, pollen, toxic fumes and gases such as carbon monoxide. Diagnostic tools such as Pulse Oximetry, blood tests for anemia, ECG and metabolic study are used to aid the diagnosis and then initiate appropriate treatment.