Of Ventilators, Inhalers and Nebulizers

Of Ventilators, Inhalers and Nebulizers

Anyone who suffers from asthma has heard of inhalers and nebulizers. The term ventilator is rather new for some of us. In the times of coronavirus, it is good to know the what these terms mean and how are they used in our health care system.

Breathing, like the beating of the heart, are autonomous functions of the body. They go on, on their own and are vital to our survival. Unless we pay attention, we don’t even know that we are breathing.

That however is not the case for people who have some form of lung or respiratory disease. 

The air passages start at the nose and mouth. The air that we breath, passes through the air pipe called the trachea, then through the two branches called bronchi, one going to the left and the other to the right lung. There are certain conditions such as allergies and infections that can cause the airways to narrow. The allergies cause them to constrict and the infection/inflammation causes narrowing by building up of the phlegm (sticky thick secretions). In cases such as these, doctors prescribe medicines to inhale in order to open (dilate) the air passages. The devices that we use to “inhale” the medicines (broncho-dilators) are called inhalers.  (You may click on these links to see what an inhaler and a nebulizer looks like)

The word “nebulize” means to turn something into a spray. Atomize is a synonym. Nebulizers create a mist or a spray. The medicines, either liquid or fine powder, are converted into fine spray by these devices which are then inhaled. One can also provide moisture to the air passages by nebulizing water without any medication. Almost everyone has seen patients in the hospital beds with a plastic tube bringing in oxygen which is then passed through a nebulizer to create a fine mist to provide moisture to the dry air passages. 

Ventilators are machines that “ventilate” the lungs. Oxygen rich air is pushed into the lungs by these machines. In other words, these machines take over the function of breathing. In patients who are unable to breath on their own, the ventilators are programmed to deliver certain number of breaths per minute, the percentage of oxygen, the volume of air, and the force with which each breath is to be delivered. Under better circumstances, the patients initiate their own breath, but the ventilators assist and reduce their effort and energy consumption while at the same time deliver increased amount of oxygen. See the photo of a ventilator here.

Since the air is pushed mechanically under pressure, measures are taken that it does not leak out from the air pipe. For that, a plastic tube, called endotracheal tube is inserted in the trachea. The tube has a thin balloon around it. After the successful insertion of the tube through the mouth into the trachea, the balloon is inflated in order to create an airtight seal. The tube is then connected to the ventilator.

When someone has such an endotracheal tube, they are unable to speak because the air is not allowed to come through their vocal cords.  These machines are life savers as they provide much needed ventilation (breathing) in patients with severe pneumonia, stroke, heart failure or coma.

Sometimes, special (medical grade) breathing masks are referred to as respirator masks. That is not be confused with ventilators.

Because of the technicalities and complexity of the ventilators and the potential of complications, only specially trained and certified personnel (respiratory therapists) are allowed to manage them. Since the ventilators are mechanical devices to move the air in and out of the lungs, the doctors can also deliver drugs used in inhalers to open the air passages or add nebulization to add moisture to the ventilators.

Although many patients who contract the coronavirus have mild symptoms, some develop severe pneumonia and have to be hospitalized. If the breathing get really difficult, these patients need respiratory support  with ventilators till the pneumonia gets better. While the hospitals in the USA have enough ventilators to deal with the current case load, there may be shortfall in the future if the number of severely infected patients requiring respiratory support continues to increase.