tag:blogger.com,1999:blog-2715968472735546962.post8145803263322451890..comments2023-12-14T02:21:18.222+01:00Comments on Bannalia: trivial notes on themes diverse: Mass exhalationJoaquín M López Muñozhttp://www.blogger.com/profile/08579853272674211100noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-2715968472735546962.post-27329130230054860282008-09-30T22:20:00.000+02:002008-09-30T22:20:00.000+02:00Oops, pressed the submit before linking to the Cao...Oops, pressed the submit before linking to the Cao article here: <A HREF="http://www.clinchem.org/cgi/content/full/52/5/800?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=1&andorexacttitle=and&andorexacttitleabs=and&fulltext=exhaled+co2&andorexactfulltext=and&searchid=1&FIRSTINDEX=0&sortspec=relevance&resourcetype=HWCIT" REL="nofollow">Breath Analysis</A><BR/><BR/>:)Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-2715968472735546962.post-3972513889638819062008-09-30T22:17:00.000+02:002008-09-30T22:17:00.000+02:00I usually don't trust USDA studies in their ge...I usually don't trust USDA studies in their generalizations because they end up claiming that a statement like "C++ templates are bad" is true. <BR/><BR/>It is however more than true that the amount of CO2 and other gases vary not only according to metabolic needs, but also due to physiological processes taking part at the pulmonary alveoli level, where the actual respiration takes place, submitted to higher control from the bulbar respiratory centers etc. This results in a peculiar mixture of CO2 with the other gases that remains constant within a given state of the individual during the alveolar exchange.<BR/><BR/>Not to mention that CO2 is also "influenced" and "influences" the blood pH and the other blood gases into a twisted game of dependence, which can end up with lowering the breath rate, one of the effects of the so called CO2 narcosis, like it happens in certain pathological states.<BR/><BR/>In anycase, with the whole organism trying to compensate, there should be a pretty valid mean upon which to base a calculation, provided such a mean is averaged properly taking under consideration the several states we find each others into during the day. The CO2 i/o should follow the classical Gaussian distribution within out physiological everyday states.<BR/><BR/>Breath analysis (and not just for measuring exhaled body mass) is an extremely valid tool and quite a good programming challenge given the problem and the hardware you are dealing with. Since you show a genuine interest for these things, I lurked through the material freely available as well in order to post back a useful resource.<BR/><BR/>Here is an interesting link which treats the problem of the different gases exhaled:<BR/><BR/>Cao & Duan, 2006: Breath Analysis: Potential for Clinical Diagnosis and Exposure Assessment - Clinical Chemistry 52: 800-811, 2006<BR/><BR/>Another free resource about the control of the respiratory rate can be given by the NIH bookshelf through this link:<BR/><BR/>http://www.ncbi.nlm.nih.gov/bookshelf/picrender.fcgi?book=cm&&partid=365&blobtype=pdf<BR/><BR/>I think that your calculation of the exhaled CO2 should be as accurate as logic allows given the input data given. It also shows the logic of C++ programmers over the pythonistas.<BR/><BR/>Thanks for your reply as well.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-2715968472735546962.post-63879261993077452722008-09-30T19:52:00.000+02:002008-09-30T19:52:00.000+02:00However, there are several other compounds that co...<I>However, there are several other compounds that could add to this, despite the striking prevalence of CO2 over them. One way to look towards this would be to include articles like the following include the following:</I><BR/>[...]<BR/><BR/>Of course the calculation is just an approximation, albeit hopefully a reasonable accurate one.<BR/><BR/>Alas the source you provide is not free, so I can't have a look at it.<BR/><BR/>A thing that struck me as odd during the writing of this entry if that I couldn't find any justified answer to the question of how much CO2 do people exhale, besides the quoted but unavailable USDA study and some coarse calculations based on CO2 breath concentration and wild guesses on respiratory frequency --which misses the fact that how much CO2 we exhale depends on what our energy consumption is.<BR/><BR/>Thank you for your comments,Joaquín M López Muñozhttps://www.blogger.com/profile/08579853272674211100noreply@blogger.comtag:blogger.com,1999:blog-2715968472735546962.post-73348375290487664682008-09-30T18:26:00.000+02:002008-09-30T18:26:00.000+02:00However, there are several other compounds that co...However, there are several other compounds that could add to this, despite the striking prevalence of CO2 over them. One way to look towards this would be to include articles like the following include the following:<BR/><BR/>Moser B. et al, 2005: Mass spectrometric profile of exhaled breath--field study by PTR-MS., Respir Physiol Neurobiol. 2005 Feb 15;145(2-3):295-300.<BR/><BR/>Needless to say that oxygen and other compounds find their way out in various forms through our nostrils, including CO, NO, H20 vapors and also volatile substances with relatively complicated structure (ketone breath of the diabetic, post-exercise ketosis are some ideas).<BR/><BR/>Overall, I really liked your post very much! :)Anonymousnoreply@blogger.com