Pulmonary edema is caused by the accumulation of fluid in the lungs due to its filtration from the surroundings. Into each of the lungs leads one bronchial tube that then branches into smaller bronchi and bronchioli. At the end of these breathing tubes are small pouches called alveoli. Around these structures are blood vessels where the exchange of oxygen and carbon dioxide takes place. If, due to any reason, the permeability of these vessels increases, then fluid leaks into the alveoli and creates pulmonary edema.
The causes of pulmonary edema
Pulmonary edema has many caused which can be separated into two categories: cardiogenic and noncardiogenic. Cardiogenic pulmonary edema occurs directly due to heart malfunction.
The occurence of pulmonary edema is caused mainly by poor heart function, most commonly left-sided heart failure. The unstable heart is unable to pump blood to the body and this blood then accumulates in the heart and lungs. This causes an increase in pressure in the blood vessels of the lungs and the filtration of fluid into the pulmonary alveoli. Heart failure can be caused by a heart attack, malfunction of the heart valves or heart arrhythmias.
Non-cardiogenic causes of pulmonary edema are not directly related to the heart. These causes are fairly rare and include damage to the alveoli after breathing in toxic fumes, aspiration of vomit, high altitudes, head trauma, damages after drowning, or after serious lung infections.
Symptoms of pulmonary edema
Shortness of breath is a typical symptom of pulmonary edema which occurs most often at night in the prone position. This is because after laying down blood from the lower part of the body moves up and therefore into the lungs. Pacients often place many pillow under their heads and even may sleep in a near sitting position. Due to the fact that there is a disruption in oxygen exchange in the lungs, cyanosis (blueish colour) can appear in the lips, fingertips and ears. Coughing can also be present, at first dry and hacking, and in more advanced stages can be accompanied by coughing up of pick foamy fluid. This is due to the further accumulation of fluid in the lungs. If in connection with heart failure, there can also be chest pain or fever.
Diagnosis of pulmonary edema
In order to diagnose pulmonary edema, the standard first step includes a chest X-ray which shows increased numbers and size of blood vessels (this correlates with the accumulation of blood in the pulmonary vessels). Also, diagnostic methods that focus on the heart are used, such as the electrocardiography (ECG) or the echocardiography.
Electocardiography is a main diagnostic tool used in cardiology. This method allows for visualisation of the electrical activity of the heart muscle. It can reveal arrhythmias and even heart attacks.
Echocardiography is a method which uses ultrasound to visualise the heart and is minimally invasive for the pacient. It detects heart size and its movement, also any possible defects of movement and of the heart valves. This diagnostic method is not very effective in obese pacients.
Treatment of pulmonary edema
The treatment of pulmonary edema includes decreasing the volume of fluid in the pulmonary blood vessels. Most often used are medications called diuretics, which increase excretion of water via the kidneys. This decreases the entire blood volume of the body. Other medications used are those that support breathing. Oxygen is also used. It is very importment to discover the reason for heart failure and then treat accordingly. In order to prevent these potential health problems, it is important to take care of your heart and live a healthy lifestyle. This includes not smoking or drinking alcohol, following a healthy diet and exercising.
Pulmonary edema is a very serious health problem that goes hand in hand with heart failure. This is why it is important to keep track of potential symptoms. If you wake up in the night with breathing problems or a cough and you sleep and breath better sitting up, then you should inform your physician about it. He/she will send you for testing and will then prescribe the needed medications. Pulmonary edema is treatable and after discovering the cause and prescribing medication, the pacient is often able to return to a normal life. Although, it is essential to follow the lifestyle advice given by your physician.