Richard Sheldon (Medical Advisor to the CA State Respiratory Care Board) gives expert video advice on: What are the most common causes of respiratory failure?; What are the most common symptoms of respiratory failure? and more...
What is respiratory failure?
Respiratory failure is a condition where the lungs have failed and they failed either in one of two areas. They've either failed in their ability to bring oxygen into the bloodsteam in adequate amounts or they failed in their inability to clear CO2. C2 is the fumes of metabolism and if they accumulate too high can cause death. The process of moving your carbon dioxide levels in your bloodstream from normal up a place where it causes death, the intermediate stages will cause unconsciousness, inability to even function or think clearly. Just like oxygen, if it gets too low in your bloodstream can cause serious malfunctioning of not only of your brain but your heart and when it gets so low that it can no longer support metabolism or cellular respiration then the organism will die.
What are the most common causes of respiratory failure?
Most common causes of respiratory failure include chronic obstructive pulmonary disease which is the fourth major cause of death in the United States now, emphysema, chronic bronchitis and of the four top ones is the only one that is increasing in frequency. The others are starting to lessen just a little bit like cancer, stroke, heart attack and the rest. But COPD, chronic obstructive pulmonary disease, is still on the increase. And it causes death by a combination of too high C2 too low oxygen. We also have other problems such as the adult respiratory distress syndrome which is the form of pulmonary edema that will kill a patient because they can't get enough oxygen into their bloodstream, however, the most common cause of death in that situation continues, the way a person continues on in ARDS is usually from infection not from hypoxemia which is the word for too low oxygen in the blood. The other main problem though with death from respiratory failure includes pneumonias, interstitial lung disease, all of these chronic illnesses that will afflict the lung can lead eventually to respiratory failure and then to death.
What are the most common symptoms of respiratory failure?
The most common symptoms of respiratory failure of course is breathlessness, the feeling that you're sufficating, that you're struggeling with each breathe. We have a term that says the work of breathing. With the term work of breathing what we mean by that is that the work that a person has to put into taking a breath is very minumal. For instance if you look at how much oxegyn you consume per minute, and then allocate each of the ten organ systems with a certain percentage of the consumption of that oxegyn. You'll find that the lung in order to do its job requires about 3 percent of the oxygen that is consumed by minute to work the pumps, and get the oxygen in, and distribute it to the rest of the body.The other organ systems like the brain, and the kidneys, and the heart consume a lot more oxygen than does the machinary in the body that brings in the oxygen. In resporitory failure, that work of breathing starts to decline dramatically. So you may see a patient in resporitory failure that the lung is requiring 25% of the oxygen just to take a breathe and move the air in and out. When that happens that means you're stealing oxygen away from the other systems that are much more used to higher levels of oxygen, and they start to shut down. So that oxygen becomes the sailable component with in this whole system much like a business. Where one part starts to shut down, requires more and more of the resources to run it and after a while it can kill the whole organism. So when the lung goes into resporitory failure, it starts demanding more of the oxygen than it would normally use. That then puts big stresses on other portions of the body such as the hearts ability to contract pump by pump goes down with the lack of oxygen. It needs a lot of oxygen to do its job. If it's not getting it because the lungs are demanding it then it starts to fail, as do the kidneys, as do the brain, and GI tract.
How is respiratory failure treated?
Respiratory failure is almost always treated by placing the patient in the intensive care unit, and then as we start to administer oxygen we check blood gases. That means that we take a little needle and place it into the artery, pull off arterial blood and then analyze it for its oxygen content, its CO2 content, and also its PH. Given that information, we can tell then, quite precisely, how much oxygen to add. Or, if the CO2 is climbing, we know that we are going to have to put a tube through the mouth, down into the lungs, blow up a little cuff at the end of the tube so it seals everything off, and then supply pressure to keep the lungs open, and then flush out the CO2. CO2's concentration in the lung is directly proportional to the volume of gas that you can get down in there to flush it out. So, as it starts to climb, you have to add more and more alveolar ventilation in order to flush that out. We find that we can do a lot to correct respiratory failure, which is determined, you have to remember, by two things: oxygenation and ventilation. Ventilation is the way we control CO2, and oxygenation is where, by virtue of the fact that we add more and more oxygen, we may add completely 100% oxygen to a patient that we are having a hard time oxygenating. Bearing in mind that we are starting off at approximately 21% oxygen on room air, we can go to 30%, 40%, 50%, and keep adding as much as we need to resolve that aspect of respiratory failure; whereas, with CO2, we can add more volume, more volume, more volume, and more volume to help flush out that CO2. There are limits, and at some point in time we can start getting into lung injury by too high an oxygen content; oxygen can burn the lung, too much volume and we can pop the lung. So, it has to be done very carefully and very knowledgably, and, at times, we run out of space and we do lose the patient because the respiratory failure overwhelms even our ability to do this. Nonetheless, there is a lot to do to resolve respiratory failure.
What is "Chronic Obstructive Pulmonary Disease" or "COPD"?
Chronic obstructive pulmonary disease or COPD is a very common disorder in the United States, and most of the world. Smoking cessation programmes in the United States have started to lessen the impact of chronic obstructive pulmonary disease, especially emphysema. However in other countries; in Europe, China, and Japan, smoking is rampant. Everybody's doing it, so chronic obstructive pulmonary disease continues to be a really serious problem, especially emphysema. Emphysema is most commonly caused by smoking. There are forms of emphysema that are inherited. There are some chemical disorders that can occur in the body, such as alpha-1 antitrypsin deficiency, that can cause a form of emphysema, but those are relatively rare. Smoking is, by and large, the main issue. We need to address the fact that the more you smoke, the higher your chances of developing these very, very debilitating disorders.