Lungs and Breathing

Many people who are admitted to intensive care are having trouble breathing. Normally, the lungs expand when we breathe in, and shrink back again when we breathe out. When we breathe in, the air fills the small pouches surrounded by tiny blood vessels deep in the lungs. They exchange oxygen that the body needs for carbon dioxide that the body needs to get rid of.

Potential Problems:

Acute Respiratory Distress Syndrome (ARDS)

The lungs become inflamed in response to injury or infection. The inflammation makes the small blood vessels leaky, and fluid collects in the lung tissues. This puts pressure on the small pouches that exchange air, and they start to close down. It becomes more and more difficult for the person to breathe.


The collapse of the air exchange pouches in some or all parts of a lung. This can happen after surgery, injury, or infection.


An inflammation of the lung caused by infection. The infection can be due to a virus, bacteria, fungi or other pathogens. The pneumonia can involve one or more lobes of the lungs.


If air enters the space around the lungs, the lungs can collapse. A hemothorax occurs when blood gets into the space around the lungs and has the same effect. The larger the area affected, the more serious the breathing problems will be.

Pulmonary embolism

A pulmonary embolism is a blood clot that forms elsewhere in the body, breaks free, and travels with the blood to the lungs. Most pulmonary embolisms come from large veins in the legs. The embolism will block off blood flow to the small sacs in the lungs and they will not work as well.

Pulmonary edema

Edema is fluid in the tissues, in this case around the lungs. The extra fluid makes it more difficult to breathe. Pulmonary edema is a common complication of critical illness. Fluid collects with gravity, so a person who is on bedrest will tend to get edema in the back and lower parts of the lungs.

Prevention and Therapies:

Oxygen therapy

The normal percentage of oxygen in the air is 21%. If a person needs a higher percent of oxygen, it is considered a medical therapy. Many patients are given between 30 – 50% oxygen. Extra oxygen can be given using nasal prongs, a mask over the nose and mouth, or by ventilator support with a tube into the lungs. Some masks use pressure to ensure the oxygen gets into the lungs. This is called BiPAP (Bi-level Positive Airway Pressure) or CPAP (Continuous Positive Airway Pressure). The pressure used at inhalation or exhalation helps prevent the lungs from collapsing all the way. If the person is on a ventilator, the positive pressure therapy is called PEEP (Positive End Expiratory Pressure).

Mechanical Ventilator

A mechanical ventilator is a machine that breathes for the patient when they are not well enough to do so on their own.  Helping a patient breathe is essential to life support.  A tube can be placed into the lungs either through the mouth or through an artificial hole in the throat called a tracheostomy. This is called intubation. The ventilator is used to support a patient who cannot breathe effectively on their own. As the patient starts to recover, the type of support offered by the machine can change so the patient can breathe more on his or her own.


A tracheostomy is a hole made into the throat just below the Adam’s apple and into the windpipe (trachea). The team will also consider making a tracheostomy if a patient has to be on a ventilator for a longer period of time. Ventilation with a tube through the mouth can become dry and uncomfortable. and could potentially damage the vocal cords if left in for a long period of time. If a person no longer needs ventilator support, the tracheostomy can be easily removed. Once removed, the site of the tracheostomy will heal fairly quickly and usually leave a small scar.

Chest Tubes and Drains

If there is a lot of fluid or air around the lungs, it can become difficult or impossible for the lungs to expand and deliver oxygen to the blood. The lungs are surrounded by the pleural membrane. This barrier helps keep the pressure higher in the lungs than in the space around it, preventing the parts of the lungs that exchange gases from collapsing. A person can end up with fluid or air around the lungs for a number of reasons, such as surgery in the chest, injury, or fluid imbalances in the body. One way to deal with fluid or air around the lungs is to insert a special drainage tube (chest tube) to remove the air or fluid, allowing the lung to re-expand.

Chest Physiotherapy

Critical illness and periods of inactivity can cause fluid (secretions) to build up in the lungs, making it harder to breathe. The physiotherapist or nurse can help patients to move the secretions out of their lungs by tapping over the areas that are filling up and helping them cough.


Suctioning is necessary to help clear a patient’s airway if they are unconscious or unable to cough effectively. Suctioning basically vacuums out any secretions (fluid, mucous). A nurse, respiratory therapist, or physiotherapist will insert the suction tube (catheter) and remove it right away. The suctioning is turned on while it is being removed from the airway.


The head of the bed should be kept between 30 and 45 degrees. This reduces the amount of work needed to breathe and reduces the risk of breathing fluid into the lungs if a person has secretions. It also reduces the chance of lung infection. Staff will change a patient’s position every couple of hours if it is safe to do so.

Endotracheal tube

An endotracheal tube is a tube inserted through the mouth down into the lungs; it is used to deliver oxygen with a ventilator directly into the lungs. The procedure of placing the tube into the lungs is called intubation.



These drugs are used to fight bacterial infections that may be blocking the lungs, as in bacterial pneumonia.


Diuretics work on the kidneys by increasing the amount of water that passes as urine. This allows the body to get rid of extra fluid, including fluid around the lungs (pulmonary edema).


If the lungs and airways become inflamed, they can swell and make it harder to breathe. Anti-inflammatories reduce this swelling.


Bronchodilators are used to open up the airways. This lets other medications such as anti-inflammatories get to where they are needed most deep in the lungs.​​​​​​​

Diagonostic Tests and Monitoring:

Chest X-rays (CXR)

Chest X-rays are a routine part of care in the intensive care unit. A technician comes around in the morning with a portable X-ray machine and x-rays most patients every day or two. The x-rays are used to check for many things, such as fluid in and around the lungs and the proper placement of chest and feeding tubes.

Magnetic Resonance Imaging (MRI)

MRIs are used to get a very detailed picture of the body tissues and organs. MRIs use a strong electromagnetic field to make two- and three-dimensional images of the area scanned. The use of a strong magnet means it is important to remove all metal before an MRI. The scanner is loud, so patients and staff are given ear plugs. Sometimes a patient will be given a substance to increase the contrast and sharpen the details of certain body parts, such as the blood vessels. Like a CT scan, an MRI is painless. Patients travel to radiology with a nurse for this test.

Blood tests

Measurements of blood gases and other blood tests are used to help diagnose problems with the lungs and many other body systems. Blood is often taken from a catheter inserted into an artery called an arterial line.


A bronchoscopy allows a physician to look inside the air passages. A bronchoscope is a special tube that has a built-in camera and a tube for suctioning and sampling. The physician can look for abnormalities in the air passages and collect samples that can be sent to the laboratory to identify infection or other diseases.

Sputum sample

Sputum is the mucous and fluid that can collect in the lungs. A sample can be collected and sent to laboratory to be tested to see what it is made up of, and if there is any disease present. Sputum is usually collected by suctioning the breathing tube.

Nuclear medicine

Nuclear medicine involves using mildly radioactive substances, called isotopes, to identify injury or disease. Certain radioactive substances will find and attach themselves to particular cell types or proteins. The person is then scanned with a special camera. The isotopes ‘light up’, telling the physicians where the cell or protein they are looking for has collected.


Ultrasound tests use the measurement of sound waves sent into the body to identify masses or fluid. It is painless and can be performed at the bedside. Ultrasounds can help a physician tell where to place a chest tube to drain fluid.