What Is Wet Lung?

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"Wet lung" is a lay term for acute respiratory distress syndrome (ARDS), when lungs are filled with fluid instead of air. The fluid 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 ARDS, including symptoms, causes, diagnosis, and treatment.

Lung exam

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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.

If you show any signs or symptoms of low oxygen or lung injury, seek medical care right away. The condition is serious and can lead to organ failure or death.


ARDS 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. 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

Risk Factors

Some people are more at risk of developing ARDS, or conditions that lead to it, than others. Risk factors include:

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 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. This can narrow the capillaries in the lungs and make oxygen transfer more difficult.

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

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: As you get older, both 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 in some patients with widespread cancer in the lungs.


Wet lung develops when lungs are damaged by injury or certain illnesses. This can cause fluid to leak into the lungs and take up space where air should be. When oxygen levels drop, organs like the heart and brain may not get the oxygen they need. Certain factors increase your risk, including lung disease, chemotherapy, and alcohol use.


There is no specific test for ARDS. Instead, your healthcare provider will make a diagnosis 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 Physical Exam

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

They will listen to your lungs to check for unusual breathing sounds or problems with air movement. They will also examine the skin and lips for a bluish tint, and look for signs of body swelling or fluid. Your oxygen level and blood pressure will be measured.

Tests and Imaging

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 is 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 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.


If your healthcare provider suspects wet lung, they'll perform a series of tests to check the levels of oxygen in your blood, rule out other conditions, and confirm the diagnosis. Prompt treatment can decrease your risk of organ failure and help increase your odds of survival.


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

Key goals of treatment include improving blood oxygen levels to prevent organ damage and treating the injury or condition that caused the condition to develop.

Treatment is different for each person, and can include breathing support, medications, or other therapies.

Breathing Support

Depending on the seriousness of your case, 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 an 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 can relieve symptoms of wet lung by treating the underlying causes and preventing complications.

Medications may include:

  • 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 Treatments

Additional treatments your healthcare provider may recommend 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.


Treatment for ARDS involves managing symptoms and making sure the body gets enough oxygen flow to the organs. Medications to treat underlying conditions and supplemental oxygen may be enough for mild cases, but people with more severe ARDS may need ventilator support.

Recovery and Prognosis

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

Physical therapy and pulmonary rehabilitation 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:

  • Quitting smoking if you smoke and avoiding secondhand smoke whenever you can
  • Getting 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 ARDS 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.

Most people recover from ARDS, but it can be fatal in 30% to 40% of cases.


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 air flow 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 ARDS 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.

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13 Sources
  1. Cleveland Clinic. Acute respiratory distress syndrome (ARDS).

  2. American Lung Association. Learn about ARDS.

  3. Saguil A, Fargo M. Acute respiratory distress syndrome: diagnosis and management. Am Fam Physician. 2012;85(4):352‐358

  4. Gibson PG, Qin L, Puah SH. COVID‐19 acute respiratory distress syndrome (ARDS): Clinical features and differences from typical pre‐COVID‐19 ARDSMed J Aust. Published online June 22, 2020. doi:10.5694/mja2.50674.

  5. O'Brien JM Jr, Lu B, Ali NA, et al. Alcohol dependence is independently associated with sepsis, septic shock, and hospital mortality among adult intensive care unit patientsCrit Care Med. 2007;35(2):345-350. doi:10.1097/01.CCM.0000254340.91644.B2

  6. Moazed F, Burnham EL, Vandivier RW, et al. Cigarette smokers have exaggerated alveolar barrier disruption in response to lipopolysaccharide inhalationThorax. 2016;71(12):1130-1136. doi:10.1136/thoraxjnl-2015-207886

  7. National Organization of Rare Disorders. Vasculitis.

  8. Gorguner M, Akgun M. Acute inhalation injuryEurasian J Med. 2010;42(1):28-35. doi:10.5152/eajm.2010.09

  9. Dulu A, Pastores SM, Park B, Riedel E, Rusch V, Halpern NA. Prevalence and mortality of acute lung injury and ARDS after lung resectionChest. 2006;130(1):73-78. doi:10.1378/chest.130.1.73

  10. Kirch C, Blot F, Fizazi K, Raynard B, Theodore C, Nitenberg G. Acute respiratory distress syndrome after chemotherapy for lung metastases from non-seminomatous germ-cell tumorsSupport Care Cancer. 2003;11(9):575-580. doi:10.1007/s00520-003-0481-5

  11. National Heart, Lung, and Blood Institute. Acute respiratory distress syndrome.

  12. American Lung Association. ARDS treatment and recovery.

  13. Zhou MT, Chen CS, Chen BC, Zhang QY, Andersson R. Acute lung injury and ARDS in acute pancreatitis: mechanisms and potential interventionWorld J Gastroenterol. 2010;16(17):2094‐2099. doi:10.3748/wjg.v16.i17.2094