The Lungs

Q: Is there anything that can be done for a patient with emphysema/COPD (chronic obstructive pulmonary disease)? How about transplants?
A: In short, yes, but nothing that will reverse the disease process. COPD is a broad category of all lung diseases where it's difficult to exhale. Emphysema is the most common, and chronic bronchitis is the other. Emphysema is a disease that is most often due to a long history of smoking, but there are rare cases of gene mutations and occupational exposures that can cause it as well. Lung tissue is comprised of a BAJILLION teeny tiny little sacs of air surrounded in a huge network of capillaries. Blood coming through drops off the carbon dioxide your body has generated, and picks up the oxygen that you just breathed in. The distance between the capillaries and the sacs of air is only one cell layer thick - this allows maximum gas exchange for your ultimate breathing pleasure. In emphysema, these thin walls have been damaged and destroyed, so the surface area available for the blood to exchange gas becomes increasingly small. See picture (never thought you'd see Encyclopedia Britannica again, did you?)

From www.britannica.com

This damage is not reversible - at least not yet anyway. So for someone with the disease, the best thing they can do is have oxygen supplementation and some medications to keep the airways open. Exercise is always good, however the extent of damage can be limiting, which creates a frustrating vicious circle. Transplants are certainly considered for some patients with emphysema. The tricky part is that there is an elaborate algorithm that goes into who receives the transplant, and if the patient is even a candidate. Usually, there can not be any other diseases that would limit the lifetime of transplanted lungs. There's no straight answer - certainly it is always a conversation that can be had with the pulmonologist.


Q: Why is it that smokers get COPD/emphysema, even decades after quitting?
A: Sadly, all lungs start declining from their peak performance around age 12. For someone who has no smoking or occupational exposure, their lung function will drop slowly throughout the years. This is normal. When smoking is brought into the equation, the deterioration takes a dive and the rate of decline is much steeper. When a smoker quits, they do not "bounce back" to their pre-smoking stage. Rather, they simply go back to the declining slope of non-smoker. Here's a good graph to illustrate the point:

From www.emedicinehealth.com

The good news is that we are all WAY over-equipped in lung capacity. The problem is that most people live fairly sedentary lives, where they are not challenging their lung capacity on a regular basis. A sedentary person can actually lose 75% of their lung capacity before they even know anything is wrong. Read: EXERCISE CAN ABSOLUTELY, 100%, POSITIVELY SAVE YOUR LIFE. If someone is concerned that maybe they're on that dotted grey line (history of smoking, but quit years ago), then what you can do is head to your local pulmonolgist and get a series of Pulmonary Function Tests (PFTs). They will tell you where you stand in terms of lung function, where you stand on that grey line (either near disability or not). There isn't anything that can be done to reverse damage, or stop the decline of lung capacity, but there are definitely ways to prevent rapid decline.


Q: What is it about steam that relieves croup in a child?
A: Interesting, nothing at all! Croup, aka larynotracheobronchitis, is a respiratory dysfunction usually brought on by a viral infection, and leads to swelling of the throat. Treatment: steroids to reduce swelling an inflammation. C'est tout! 
Edit from a pediatrician: "While the steamy shower may not treat croup, the warm, moist air (or the cold moist air from outdoors or from the freezer) may provide temporary and quick relief of the barky cough spasms.  Also,not every child gets steroids, just the ones where the attack is more severe, lasts more than a few nights or there is a history of asthma."


Q: How do free divers hold their breath for so long?
A: They typically start by hyperventilating, and then use muscles in their throat to push in an additional 1L of air into their lungs. Then they lower their heart and metabolic rate (diving into cold water helps slow metabolism) so that their body simply doesn't need that much new oxygen. The last part is probably suffering through pain to get the max amount of time holding their breath.