Pulmonary edema
Lung congestion; Lung water; Pulmonary congestion; Heart failure - pulmonary edema
Pulmonary edema is an abnormal buildup of fluid in the lungs. This buildup of fluid leads to shortness of breath.
Heart failure, also referred to as congestive heart failure, is a condition in which the heart’s pumping ability is not sufficient to meet the body’s need for oxygen-rich blood. As a result, arm and leg muscles may tire more quickly, and the kidneys may not function normally. The kidneys filter fluid and waste products from the blood into the urine, but when the heart cannot pump adequately, the kidneys malfunction and cannot remove excess fluid from the blood. As the amount of fluid in the blood stream increases, blood pressure rises, forcing the failing heart to work harder. This creates a vicious circle. The term congestive heart failure is technically reserved for situations in which heart failure has led to edema or fluid build-up in the body. Although not all heart failure is congestive, the terms are often used interchangeably. Heart failure may either be left-sided, in which pulmonary edema is the main symptom, or right-sided, in which hepatomegaly or liver enlargement and systemic edema are the main symptoms. In many instances, both sides of the heart are involved. Any disorder that directly affects the heart can lead to heart failure, as can some disorders that indirectly affect the heart. In the United States, the most common causes of heart failure are ischemic heart disease and hypertension. Arrhythmias and valve diseases are also common causes. Less common causes include illicit drugs, vitamin deficiency, and hyperthyroidism. Therapy usually requires a combination of multiple drugs and lifestyle changes. There are many different drugs used to treat heart failure. The choice of therapy is influenced by the patient’s age, renal function, serum potassium levels, racial background, blood pressure, volume status, and clinical condition. Surgical therapy, including transplantation in severe cases, may be required.
The major features of the lungs include the bronchi, the bronchioles and the alveoli. The alveoli are the microscopic blood vessel-lined sacks in which oxygen and carbon dioxide gas are exchanged.
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Causes
Pulmonary edema is often caused by congestive heart failure. When the heart is not able to pump efficiently, blood can back up into the veins that take blood through the lungs.
As the pressure in these blood vessels increases, fluid is pushed into the air spaces (alveoli) in the lungs. This fluid reduces normal oxygen movement through the lungs. These two factors combine to cause shortness of breath.
Congestive heart failure that leads to pulmonary edema may be caused by:
- Heart attack, or any disease of the heart that weakens or stiffens the heart muscle (cardiomyopathy)
- Leaking or narrowed heart valves (mitral or aortic valves)
- Sudden, severe high blood pressure (hypertension)
Pulmonary edema may also be caused by:
- Certain medicines
- High altitude exposure
- Kidney failure
- Narrowed arteries that bring blood to the kidneys
- Lung damage caused by poisonous gas or severe infection
- Major injury
Heart failure, also referred to as congestive heart failure, is a condition in which the heart’s pumping ability is not sufficient to meet the body’s need for oxygen-rich blood. As a result, arm and leg muscles may tire more quickly, and the kidneys may not function normally. The kidneys filter fluid and waste products from the blood into the urine, but when the heart cannot pump adequately, the kidneys malfunction and cannot remove excess fluid from the blood. As the amount of fluid in the blood stream increases, blood pressure rises, forcing the failing heart to work harder. This creates a vicious circle. The term congestive heart failure is technically reserved for situations in which heart failure has led to edema or fluid build-up in the body. Although not all heart failure is congestive, the terms are often used interchangeably. Heart failure may either be left-sided, in which pulmonary edema is the main symptom, or right-sided, in which hepatomegaly or liver enlargement and systemic edema are the main symptoms. In many instances, both sides of the heart are involved. Any disorder that directly affects the heart can lead to heart failure, as can some disorders that indirectly affect the heart. In the United States, the most common causes of heart failure are ischemic heart disease and hypertension. Arrhythmias and valve diseases are also common causes. Less common causes include illicit drugs, vitamin deficiency, and hyperthyroidism. Therapy usually requires a combination of multiple drugs and lifestyle changes. There are many different drugs used to treat heart failure. The choice of therapy is influenced by the patient’s age, renal function, serum potassium levels, racial background, blood pressure, volume status, and clinical condition. Surgical therapy, including transplantation in severe cases, may be required.
Symptoms
Symptoms of pulmonary edema may include:
- Coughing up blood or bloody froth
- Difficulty breathing when lying down (orthopnea)
- Feeling of "air hunger" or "drowning" (This feeling is called "paroxysmal nocturnal dyspnea" if it causes you to wake up 1 to 2 hours after falling asleep and struggle to catch your breath.)
- Grunting, gurgling, or wheezing sounds with breathing
- Problems speaking in full sentences because of shortness of breath
Other symptoms may include:
- Anxiety or restlessness
- Decrease in level of alertness
- Leg or abdominal swelling
- Pale skin
- Sweating (excessive)
Exams and Tests
The health care provider will perform a thorough physical exam.
The provider will listen to your lungs and heart with a stethoscope to check for:
- Abnormal heart sounds
- Crackles in your lungs, called rales
- Increased heart rate (tachycardia)
- Rapid breathing (tachypnea)
Other things that may be seen during the exam include:
- Leg or abdominal swelling
- Abnormalities of your neck veins (which can show that there is too much fluid in your body)
- Pale or blue skin color (pallor or cyanosis)
Possible tests include:
- Blood chemistries
- Blood oxygen levels (oximetry or arterial blood gases)
- Chest x-ray
- Complete blood count (CBC)
- Echocardiogram (ultrasound of the heart) to see if there are problems with the heart muscle
- Electrocardiogram (ECG) to look for signs of a heart attack or problems with the heart rhythm
Treatment
Pulmonary edema is almost always treated in the emergency room or hospital. You may need to be in an intensive care unit (ICU).
- Oxygen is given through a face mask or tiny plastic tubes are placed in the nose.
- A breathing tube may be placed into the windpipe (trachea) so you can be connected to a breathing machine (ventilator) if you cannot breathe well on your own.
The cause of edema should be identified and treated quickly. For example, if a heart attack has caused the condition, it must be treated right away.
Medicines that may be used include:
- Diuretics that remove excess fluid from the body
- Medicines that strengthen the heart muscle, control the heartbeat, or relieve pressure on the heart
- Other medicines when heart failure is not the cause of the pulmonary edema
Outlook (Prognosis)
The outlook depends on the cause. The condition may get better quickly or slowly. Some people may need to use a breathing machine for a long time. If not treated, this condition can be life threatening.
When to Contact a Medical Professional
Go to the emergency room or call 911 or the local emergency number if you have breathing problems.
Prevention
Take all your medicines as directed if you have a disease that can lead to pulmonary edema or a weakened heart muscle.
Following a healthy diet that is low in salt and fat, and controlling your other risk factors can reduce the risk of developing this condition.
References
Mann DL. Management of heart failure patients with reduced ejection fraction. In: Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 12th ed. Philadelphia, PA: Elsevier; 2022:chap 50.
Meyer NJ, Matthay MA. Pulmonary edema. In: Broaddus VC, Ernst JD, King TE, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 7th ed. Philadelphia, PA: Elsevier; 2022:chap 133.
Rogers JG, O'Connor CM. Heart failure: pathophysiology and diagnosis. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 52.
Version Info
Last reviewed on: 1/9/2022
Reviewed by: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
