Rick007 wrote:Hi Todzo, Lots of good information.
Todzo wrote:Minute volume I use to help me determine nighttime breathing stability. For me I like to see a value under 6 lpm for the nighttime average. I like to see the 95% no more than 3 lpm above that. I know that the max can vary for many reasons but it is comforting to see it close to the 95%. The higher the nighttime average and the further the others are above that the more I am concerned that breathing instability trounced my night of sleep.
It is interesting that you arrived at those particular values. I understand that very low values would be a problem, but why would higher values be a problem?. Why are you concerned about staying under 6 lpm on average?. My median is 7.5 and 95% is 9.75.
Post traumatic event the anniversary of the event would land me in ER for a couple of years. My therapy changed dramatically. I found myself waking up breathing very hard, very dry mouth, aerophagia. I totally lost circadian rhythm showing a non-24 sleep wake pattern with missing days. It was very hard on me.
Then, while listening to an Apnea related Webcast I was given some very basic instruction on how I could clear my nose simply by breathing less. It worked. It worked without me holding my nose and bobbing up and down (I wanted my hands free to take notes). This was my simple introduction to eucapnic breathing techniques.
As they talked about the physiology involved with hypocapnic, eucapnic, and hypercapnic breathing it became obvious to me that the panic attacks which landed me in ER and would keep me up for days at a time leading to the ER visit consisted of a whole lot of hyperventilation. A lot of hypocapnic breathing if you will. As I listened to the basics of how eucapnic breathing techniques work I became concerned that you could “go too far” and make for hypercapnic breathing if you did not have feedback of some sort. Well if you are hypocapnic vasoconstriction will occur and your heart will work hard to compensate. If you are hypercapnic vasodilation will occur and your heart will work hard to now try to fill the open hoses. It seems that lowest heart rate holding exertion constant might work as a guide.
So my pulse oximeter went on my wrist and I started the process sitting at my computer. It is not easy to control breathing rate and volume while watching for changes in heart rate to find the lowest heart rate with exertion held constant. It took me hours to get it down. Fortunately, along the way I noticed that the SpO2 reading would be consistent when the lowest heart rates were found. Back then an SpO2 reading of 96% at my desk (97% on a treadmill) resulted in the lowest heart rates (and a clear nose, and warm feet, and better thinking, more endurance, an un-knotted stomach (after several minutes) and no pain in my knees as I exercise and many other good changes I have found along the way). Likely because I moved to a higher altitude or perhaps because I am in better shape it is now 95% at the desk and 96% with constant moderate exercise. I make a point of using the pulse oximeter as a guide when I am on a cycle which is partially done to keep arthritis out of my knees. Pain in my knees does develop if I over breath (or at least it used to) and I like the idea of the tissues in the knee having the circulation and oxygenation they need to heal as I exercise.
Then it was time to try to do some pulse oximeter guided eucapnic breathing while using CPAP. I found this so hard to do that I decided to give up after only about an hour and practice my pulse oximeter guided eucapnic breathing for several days (I wore my pulse oximeter constantly for the first three months) to get it down a bit more before I would try it with the machine again. I know from this very well that the pressure of CPAP makes it difficult to breath eucapnically. For me it is already easy to breath too much. The pressure of CPAP simply adds to that problem.
So I hope you are beginning to understand why it is important to me to not over breath while using the machine. You would understand a bit better if you searched out what hyperventilation is and does. It would take you a bit further if you looked into the changes which occur in the brain due to it's vascular carbon dioxide reactivity. Further yet could you go if you looked into hypocapnic central apneas, CPAP and ventilatory instability and how this relates to respiratory effort related arousals. It is very very important to not over breath. But the pressure of CPAP makes it much easier to over breath.
As for why six liters per minute. I am average size and six liters per minute is the expected rate at rest. As well I know from looking at my data for several years now that I will feel and do better if I see things resting near six liters per minute average minute ventilation.
As for why I get concerned if the numbers not average go high, well, what do you think causes respiratory effort related arousals? And if you have one of those, your stress hormones will rise – so – you will be much more likely to have another. More events (of any kind) less breathing stability.
