I had a patient recently ask me the difference between a ventilator and a respirator. I thought this would be worth posting because, although this seems like a play on words, there is a major difference between respiration and ventilation.
So often on TV and in books, there are references to a respirator. No matter how many times ER or your favorite soap opera makes reference to one, the machine they are referring to is not a respirator. Respiration is the act of oxygen and carbon dioxide exchange. This is a physiological process that cannot be replicated by a ventilator.
What about a ventilator, what does it do? The ventilator is used on patients who go into respiratory failure, or cannot maintain their airway for some reason. Respiratory failure occurs when the body's metabolic needs are not being met. If this isn't corrected, the patient can become so labored in their breathing that cardiac arrest can occur. When this line is crossed, or about to be crossed, the patient needs to be intubated. This is the process of having a tube placed in the trachea (windpipe) so that the ventilator can be hook up to it. The ventilator works by pushing air in and out of the lungs. This simulates breathing. What is nice about a ventilator is that the amount of oxygen can be adjusted accordingly as well as things like the amount of air given during each breath and how many breathes per minute. The machine also allow the practitioner to constantly monitor the lung mechanics such as compliance (lung stiffness), and resistance (airway resistance from inflammation and constriction).
The patient will be treated for the underlying problem whether it be a severe exacerbation from COPD, or pneumonia, or sepsis (systemic infection). Once these things have been treated, then the patient is slowly weaned off the ventilator. Different approaches are use, but typically it involves backing off the support until the patient shows they can handle the workload of breathing on their own. There are also some tests that can be done on the ventilator to assess the patient's ability to breathe on their own.
There are machines that can work by exchanging oxygen and carbon dioxide, but they are very invasive and not very practical in most circumstances. So next time you hear the word respirator you can say, “Hey, that is a ventilator, Craig on BBLW educated me on the difference between ventilation and respiration.”