And, considering about half of all breathing treatments I do are either for pneumonia or cardiac asthma, I am hereby convinced that even doctors have no clue what the difference between true asthma and cardiac asthma is.
So, that is what we will learn in today's class:
According to the Mayoclinic.com, here is the definition of Cardiac Asthma:
The term "cardiac asthma" refers to wheezing associated with congestive heart failure. It isn't true asthma.Cardiac asthma is mainly caused due to increased pressure in the pulmonary vessels causing fluid to fill the air sacs, "preventing them from absorbing oxygen," and making the person feel extremely short-of-breath.
As a result of congestive heart failure, fluid can build up in the lungs (pulmonary dema). This causes signs and symptoms — such as shortness of breath, coughing and wheezing — that may mimic asthma. True asthma is a chronic condition caused by inflammation of the airways, which can lead to breathing difficulties.
The distinction is important because treatments for asthma and heart failure are very different
This same increased pulmonary vessel pressure (increased pulmonary vascular resistance) in turn squeezes the bronchioles and causes the wheeze and other symptoms that mimic real asthma, and this is why this "problem" is quite often mistaken for asthma and treated with bronchodilators.
I was flabbergasted when I found this article a few years ago, because I knew I was correct in this, but have not found any evidence to support my claim other than what I learned one day in respiratory therapy school. However, even in RT school, one of my teachers mentioned cardiac asthma and cardiac wheeze, but did not give any further detail.
So, here we have it -- the further detail; the evidence that cardiac asthma and asthma have similar symptoms but must be treated as unique illnesses.
When Cardiac Asthma is treated as bronchospasm, all we are doing is putting in more fluid already fluid filled lungs. What we need to do is give a diuretic to get rid of the fluid and, if the heart is causing the pulmonary edema, perhaps provide drugs to increase the contractility of the heart to reduce the pulmonary pressure.
Other than the heart, there are other diseases that can cause pulmonary edema and, thus, cardiac asthma, and these include pneumonia, exposure to toxin, and high altitudes. It is the job of the nurse, the respiratory therapist and (ahem) the doctor to determine the cause of the symptoms and treat the symptoms appropriately.
We'll consider this RT Cave rule #26: Cardiac Asthma should not be treated as asthma. Throat wheezes, upper airway wheezes, and dyspnea on exertion are signs of cardiac asthma, and a wise medical specialist will not confuse this with asthma.