What Is Wet Lung?

"Wet lung" is a casual term for acute respiratory distress syndrome (ARDS). This condition occurs when the lungs are filled with fluid instead of air. The fluid in wet lung could be pus from infection, fluid backed up in the lungs from heart disease, or blood from either lung or heart disease.

Wet lung can affect anyone regardless of age. It is a medical emergency and it can be life-threatening if left untreated.

This article outlines what you need to know about wet lung (ARDS), including symptoms, causes, diagnosis, and treatment.

Wet Lung Symptoms

Symptoms and signs of wet lung can vary, depending on the underlying cause. They include:

• Breathing problems: These can include severe shortness of breath, rapid, shallow breathing, or pain while breathing.
• Rapid heart rate: Trouble breathing can make your heart work harder.
• Cough: This could be a dry, hacking cough, or one that produces phlegm.
• Abnormal breathing sounds: Also called rales or crackles, which can be heard when the lungs are examined with a stethoscope.
• Fatigue: Lower levels of oxygen in the blood can lead to muscle weakness and extreme tiredness.
• Cyanosis: Bluish lips and nails happen due to lowered oxygen levels in the blood.

In cases where wet lung is caused by a severe infection like sepsis, symptoms can also include low blood pressure or fever.

Though most people who develop wet lung are already in the hospital following a trauma, infection, or other illness, sometimes ARDS symptoms can appear at home.

Wet Lung Causes

Wet lung occurs when the small air sacs that exchange oxygen and carbon dioxide (alveoli) are damaged in some way by illness or injury.

When you breathe air into your lungs, it enters ducts that deliver it to the alveoli. Oxygen passes through small blood vessels in the alveoli and into the bloodstream. From there, oxygen is transported to your heart, liver, kidneys, brain, and other organs.

When alveoli are compromised, fluid such as pus or blood can build up in the sacs, making it hard for the lungs to fill with air. This interferes with the transfer of oxygen and carbon dioxide in the lungs.

Many different conditions and illnesses can lead to wet lung/ARDS. These may include:

• Viral or bacterial infections, such as pneumonia, flu, or COVID-19
• Sepsis or septic shock
• Traumatic lung injuries, including burns
• Chemical inhalation
• Accidental inhalation of vomit or food
• Acute pancreatitis

What Increases Your Risk

Wet lung can happen for many reasons. Some people are more at risk of developing ARDS, or conditions that lead to it, than others.

Alcohol use: Excessive alcohol use or abuse has been linked to an increased risk of sepsis, a leading cause of ARDS. In addition:

• Heavy drinking is associated with other conditions that can lower the body's immune response, increasing one's risk for infection that can make wet lung more likely.
• People who abuse alcohol may be more likely to accidentally breathe in food, beverages, or vomit, which can displace air just like blood or pus would.

Lung conditions or tobacco use: There are a number of diseases and conditions that can damage lung function and create an environment that encourages wet lung/ARDS to develop. Pneumonia is one example. Smoking can also cause damage to the alveoli that makes it hard for your lungs to clear fluid.

Blood vessel inflammation: Also called vasculitis, inflammation in the arteries, veins, or capillaries can happen anywhere in the body, including the lungs. It can lead to wet lung if it narrows the capillaries in the lungs and makes oxygen transfer more difficult.

Environmental factors: Long-term exposure to toxic chemicals or pollution can cause lung damage that builds up over time. ARDS/wet lung can also happen from a sudden exposures to dangerous chemical fumes (or toxic combinations, like bleach and ammonia) that damage the lungs quickly.

Lung surgery: Wet lung is a complication of certain types of lung surgeries, like a lung resection (when part of the lung is removed).

Age: Wet lung can also become a more likely possibility with age. As you get older, both your lung function and immune response can weaken. This can make it harder to fight off infections that could lead to ARDS.

Chemotherapy: ARDS has been linked to chemotherapy.

How Wet Lung Is Diagnosed

There is no specific test for ARDS. Instead, your healthcare provider will make a diagnosis of wet lung based on medical history, a physical exam, and the results of imaging or other tests that can rule out other conditions that have similar symptoms.

Medical History and a Physical Exam

Your healthcare provider will ask you about any medical conditions and circumstances that could increase your risk for wet lung. They will also ask you about your symptoms and whether you have an existing heart or lung condition.

In your physical exam, a healthcare provider will:

• Listen to your lungs to check for unusual breathing sounds or problems with air movement, which can be a sign of ARDS
• Examine the skin and lips for a bluish tint
• Look for signs of body swelling or fluid
  

Tests and Imaging

There are a range of tests that can be used to check for wet lung.

First, your oxygen level and blood pressure will be measured.

Pulse oximetry is used to assess your blood oxygen levels. A sensor is attached to the skin or placed on your hand or foot, and a reading appears on a monitor in a few seconds.

Your healthcare provider will also request blood work to determine oxygen levels using samples taken from an artery (usually in the wrist). Low levels of oxygen in the blood are also a sign of ARDS.

Your healthcare provider may also check your blood for signs of infection, or heart and kidney problems.

Fluid accumulation in the lungs or heart enlargement can be spotted using imaging studies. X-rays and computerized tomography (CT) scans may be considered, though CT scans can offer more detailed information about heart and lung structures. Fluid in the air sacs of the lungs can confirm ARDS.

An echocardiogram or electrocardiogram, both heart function tests, can rule out heart conditions that mimic ARDS.

A lung biopsy may be done to help rule out other conditions that could be causing your symptoms. This involves taking a sample of tissue from the lung and having it examined under a microscope.

Wet Lung Treatment

There is no cure for wet lung. Instead, the condition is treated by managing symptoms.

Improving blood oxygen levels to prevent organ damage and treating the injury or condition that caused the condition to develop are the key goals of treatment.

This may involve breathing support, medications, or other therapies. Treatment is different for each person.

Breathing Support

Depending on the seriousness of your case of wet lung, your body may need extra support to breathe or to improve oxygen flow.

Milder cases may only require supplemental oxygen (delivered through a mask that fits over the nose and mouth).

People with more severe ARDS may require ventilation. A mechanical ventilator pushes air into the lungs and helps force some of the fluid out of the alveoli.

If ventilation isn't enough to sufficiently oxygenate the blood, a device like extracorporeal membrane oxygenation (ECMO) may be used. This works as an artificial lung: Blood is pumped into the machine, where oxygen is added and carbon dioxide is removed, then pumped back into the body.

Finally, the body may be positioned facedown to help more oxygen get into the lungs.

Medications

Medications can relieve symptoms of wet lung by treating the underlying causes and preventing complications.

Wet lung can be treated with medications such as:

• Antibiotics to treat infections
• Sedatives to manage anxiety and make it easier for you to breathe on a ventilator or on your own
• Blood thinners to prevent and stop blood clots from developing or getting worse
• Pain medications as needed
• Acid-reducing drugs to prevent stress ulcers that might cause intestinal bleeding

Other Wet Lung Treatments

Additional treatments your healthcare provider may recommend for wet lung include:

• Fluid management to monitor and balance out the fluid in the body to keep blood pressure regulated and help oxygen reach the organs
• Nutritional support if on a ventilator to make sure you are getting the right nutrients
• Physical therapy to maintain muscle strength and prevent sores: Movement can shorten the time on the ventilator and improve recovery after a person leaves the hospital.
  

Wet Lung Recovery and Prognosis

In some cases, the road to recovering from ARDS can be hard and it can take months or years. Some people with wet lung will need additional hospital visits. Make sure you are asking for help from loved ones, especially when you first come home from the hospital.

Wet lung sometimes gets better with physical therapy and pulmonary rehabilitation, which can help you regain lung function, improve your overall strength during the recovery process, and help you resume your normal activities. If your healthcare provider recommends these, be sure to pursue them.

While recovering from ARDS, you should do everything you can to protect your lungs. This includes:

• Quit smoking if you smoke and avoid secondhand smoke whenever you can
• Get vaccinated yearly with the flu shot and the pneumonia vaccine every five years to reduce your risk for lung infections

The prognosis for patients with wet lung depends on the underlying cause, how bad the case is, whether a ventilator was used and if organs were damaged due to decreased oxygen.

Patients who recover from ARDS may have scarring in the lungs that can impact lung function even after recovery. Scarring is more common in patients who have been on a ventilator.

People who develop ARDS during a COVID-19 infection have a greater risk of developing long-COVID, or COVID-related symptoms that last more than a few weeks after infection. Obesity appears to increase this risk.

Most people recover from ARDS, but it can be fatal.

Summary

A dangerous condition, ARDS—or wet lung—happens when the lungs are damaged by illness or injury and fill with fluid instead of air. This interferes with airflow in the lungs and oxygen transfer to the rest of the body. Organ failure and, in some cases, death can result.

ARDS can develop suddenly and cause damage quickly. In addition to taking steps to minimize your personal risk, it's important to know the signs of ARDS (breathing trouble, bluish lips/nails, etc.) Seek medical care right away if they occur.

Treatments can help manage symptoms and help you recover, though their effectiveness depends on the case.

A Word From Verywell

It is not unusual for people who have had wet lung or another lung condition to experience depression.

If you find you are feeling depressed or struggling to cope, joining a support group for others living with lung conditions or getting in touch with a mental health professional can be helpful.