The respiratory system is responsible for exchanging carbon dioxide for oxygen. The alveoli, the air sacs that line the interior of the lungs, help in that process. Pulmonary Edema occurs when fluid builds up in the alveoli. This build-up interferes with the exchange of gas and leads to respiratory failure. It can strike all at once or occur over time. When it happens suddenly, it is a medical emergency and must be dealt with immediately.
Patients who are in hospital with acute pulmonary edema have a higher risk of mortality. Especially if they also have Coronary Artery Disease that has already weakened the heart. Up to 20% of those who were admitted to the hospital for edema were re-admitted for non-fatal heart failure within 45 months. There is clear evidence that patients who do not change their lifestyle after experiencing pulmonary edema are more likely to die from it in the future.
Causes of Pulmonary Edema
The reasons for pulmonary edema vary widely. The body is intricately connected, so when an event impacts one area of the body, other parts respond. The alveoli flood for one of two reasons. Either there is not enough oxygen in the bloodstream, or the body cannot get rid of enough carbon dioxide. Some possible causes include those that impact the lungs directly, like pneumonia, trauma, inflammation or near-drowning. Other causes originate in other parts of the body: organ failure, sepsis, or brain injuries. Finally, external causes include exposure to certain chemicals, reaction to medication, drug overdose and even high altitude.
Symptoms of Pulmonary Edema
The symptoms of pulmonary edema vary depending on whether the fluid hits suddenly or appears over time. Patients with acute pulmonary edema have difficulty breathing that includes a feeling of suffocation. Excessive sweating, anxiety, pale skin and chest pain often accompany this, leading to a belief that they may be having a heart attack. Heart palpitations, wheezing and a cough that occurs with pink or frothy sputum also occur. Chronic pulmonary edema is less extreme in its symptoms. Patients report that they have difficulty breathing when they lay down or experience severe breathlessness at night. They may gain weight quickly from the fluid or see the swelling in their feet or legs. They are abnormally fatigued.
Diagnosis of Pulmonary Edema
To make a proper diagnosis of pulmonary edema, a doctor will listen to a patient’s lungs, noting any crackling or wheezing noises. They will observe the heart as well, paying attention to abnormal rhythm patterns. A comprehensive blood test that reveals the blood oxygen levels will indicate whether the body is getting enough oxygen from respiration. The bloodwork will also show electrolyte levels, blood counts, and functions of the kidney and liver. Each measurement can be considered part of a puzzle. A chest x-ray might be part of the final piece of the puzzle: if it shows fluid in or around the lungs, then they are likely dealing with edema.
Confusion of Plural Effusion vs. Pulmonary Edema
Pulmonary edema and pleural effusion both relate to water collecting in the lung area and results in difficulty breathing. Pleural effusion involves fluid collecting outside of the lungs, in the pleural layers that surround the lungs. Edema involves the collection of water inside the lungs themselves, accumulating in the alveoli. Both are dangerous conditions that need to treatment immediately.
Treatment for Pulmonary Edema
The most important thing to do when a patient is suffering from pulmonary edema is to raise his or her oxygen levels. A face mask placed over the mouth and nose or plastic-pronged plastic tubing in the nasal canal will help the lungs bring more oxygen into the body. In extreme cases, doctors may need to place the patient on a ventilator, a machine that breathes for the patient. If circulatory problems cause the edema, doctors can also use intravenous medication to remove some of the fluid. Prescription medication is available to keep fluid from building up in the body.
Risk Factors and Complications
People who have heart disease are most likely to develop pulmonary edema, making it essential for them to maintain a healthy lifestyle. Others who may be at a higher risk for developing edema include those who have had the condition before and those who have weakened lungs from tuberculosis or chronic obstructive pulmonary disorder (COPD). It can also strike those who have a blood disorder that has left their immune system compromised.
Cardiogenic Pulmonary Edema
If the fluid in the lungs is caused directly as a result of a heart problem, it is known as Cardiogenic Pulmonary Edema. Some of the causes of this type of edema include congestive heart failure, where the left ventricle of the heart can’t pump enough blood to meet the needs of the rest of the body, fluid overload, pericardial effusion or severe arrhythmia.
Like many other diseases, pulmonary edema is preventable. Patients who are at risk of pulmonary edema should take special care of their heart. Lose weight and eat a low-salt diet, lower cholesterol levels, exercise, and stop smoking.
What is the Prognosis of Pulmonary Edema?
Patients who experience acute pulmonary edema and are treated quickly often recover fully from the episode. Those who are medically fragile can expect a longer recovery time and continued treatment with medications that will help to strengthen the heart and lungs as well as eliminate fluid build-up. Furthermore, patients need to exercise regularly and eat healthy foods, as this will keep the immune system strong and the body systems working together.