Talk:Hyperventilation

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 * Reduced carbon dioxide concentration causes the blood vessels in the brain to contract, resulting in reduced blood flow to the brain. It also affects the nerves, and can cause heart arrhythmias.

Why and how does this happen? AxelBoldt 05:26, 24 Dec 2004 (UTC)


 * Offhand, I don't remember reading that hypocapnea (reduced carbon dioxide concentration) directly causes any blood vessels to constrict. It can affect nerves through a different mechanism, in that hypocapnea causes a shift in pH levels and that causes hypocalcemia which causes nerves to tingle (and I suppose, that that can cause heart arrhythmias although I would imagine that arrhythmias caused by hyperventilation to be quite rare). Alex.tan 17:48, 25 Dec 2004 (UTC)


 * In this artice they mention how hypercapnea dilates brain blood vessels, (and hypocapnea accordingly constricts them). They don't clearly say why the body does this though, what the point is. My conjecture: under hypercapnea, the brain vessels "think falsely" that the brain is currently working hard, using up a lot of oxygen and producing a lot of carbon dioxide. So they dilate, to bring more oxygen in. But I haven't read that anywhere. AxelBoldt 21:36, 1 Jan 2005 (UTC)


 * Hypercapnea causing increased blood flow to the brain makes sense. It's not "thinking falsely", it's under the assumption (usually correct) that increased carbon dioxide concentration means reduced oxygen concentration. The bottom line is that there are more chemoreceptors measuring carbon dioxide levels than oxygen levels in the body. However, hypocapnea has much less of an effect on blood vessels given that physiological pCO2 levels range from 35-45 or so and you really have to hyperventilate fast for a period of time to get them anywhere near 20 whereas raising pCO2 levels just takes holding your breath for a short lenght of time. I still find it difficult to correlate heart arrhythmias with hypocapnea secondary to hyperventilation. Alex.tan 14:36, 6 Jan 2005 (UTC)

Split
We should either have both tachypnea merged with hyperventilation and bradypnea merged with hypoventilation or we should have neither merged for continuity. Please look at the bradypnea page and help us decide wheter that should be merged with hypoventilation (and an explanation added like is the case with tachypnea/hyperventilation page) or if the hyperventilation page should be separated from tachypnea. Thanks! Ayvah 13:13, 8 June 2006 (UTC)


 * I personally think that tachypnea whould be split from hyperventilation because there are enough differences between the two that the information on hyperventilation isn't always useful for someone researching tachypnea (I speak from experience here - I need info on tachypnea and can't find it anywhere but find hyperventilation information wherever I search). Also, looking at the dates on this page, I understand that I'm coming in a little after the fact, but I figured that'd be alright with everyone...if I'm wrong about that, feel free to point it out... Jay 01:09, 7 April 2007 (UTC)


 * Tachypnea, hyperpnea, and hyperventilation are all different from each other. They all involve breathing fast, but imply slightly different mechanisms.  They should each have their own page. Otherwise, it implies that one is subtype of another (tachypnea is the most general though).  Cmcnicoll 18:32, 13 April 2007 (UTC)

Hyperpnia should not be used interchangeably with hyperventilation. As I understood it, hyperventilation was the increased alveolar ventilation exceeding the metabolic demand for oxygen, this increases the alveolar partial pressure of oxygen (due to diffusion gradient - Fick's Law). Hyperpnia on the other hand is the increase in alveolar ventilation with an increased metabolic demand (as seen in excercise).

Definition should be changed with a better reference. Hyperventilation is the process of abnormally prolonged, rapid, and deep breathing (polypnea), resulting in increased alveolar ventilation which reduces carbon dioxide tension leading to alkalosis. (Dorland, W.A., Dorland's Illustrated Medical Dictionary, 2000. W.B. Saunders Company, Philadelphia, USA) —Preceding unsigned comment added by 210.49.127.90 (talk) 08:41, 31 August 2007 (UTC)


 * Split please, these are 3 different terms. --Steven Fruitsmaak (Reply) 23:26, 28 December 2007 (UTC)


 * Agree, split. Mr. Absurd (talk) 05:32, 7 January 2008 (UTC)


 * Done.   --209.244.43.122 (talk) 20:41, 5 March 2008 (UTC)

Treatment
This section needs both revisions and additions. VodkaJazz 21:59, 28 January 2006 (UTC)

Treatment for the broad term hyperventilation will be hard to summarise as clinically there are three forms, artificial (mechanical ventilation), chronic (due to disease or syndrome such as chronic generalised anxiety syndrome) and psychogenic of which cause is often undiagnosable but still requires prompt treatment. The whole article would have to be expanded to accurately add a treatment thread.

Question on Treatment
"The common treatment of breathing into a paper bag is no longer recommended by physicians and nurses, as it can cause the carbon dioxide level to rise too rapidly"

Are there any sources to support this? Chrisjsaunders 15:18 (BST), 26 July 2006

There are many sources such as cited below by Alexspence that suggest alternatives to the rebreathing treatment or even suggest that rebreathing may do more harm than good. However article fails to cite such sources. Anyhow the existence of such sources does not really support the assertion that it "is no longer recommended [by anyone]". (Article no longer says "physicians and nurses"). Indeed some time after the first studies that point to the ineffectiveness of the rebreathing treatment I continue to see this treatment recommend in books written or at least reviewed by doctors. (Now I guess I need to add citations here to support that). Anyhow I've tagged the section as needing references. Brian McCauley, 8 November 2008 (UTC).

I don't know of any sources, but Buteyko Breathing Therapists use a exercise called the Anti-Hyperventilation Exercise to take the place of a paper bag, this simple breathing exercise puts the gap or pause back in to rapid breathing and helps the breathing to slow down, you can find out more at Buteyko Method or at Buteyko. Alexspence 11 May 2007

"Hyperventilation can be self induced..."
This (misspelled) line, the last line of the first paragraph, is in direct conflict with the rest of the article. It reads that hyperventilation induces adrenaline rushes (not stated anywhere else in the article) and allows for clearer thought (while the article goes on to state that hyperventilation actually restricts blood flow to the brain). I'm going to remove it.

Treatment (3)
Hi,

The section treatment now both discourages and prescribes the use of paper bags as a treatment for hyperventilation. For the uninformed reader, this will seem very confusing.

Also, the last paragraph above "treatment" begins in a weird way and contains seemingly nonsensical information. I would like to propose to remove it. Cheers, 92.108.16.46 (talk) 11:44, 25 February 2009 (UTC)

"Hyperventilation is not the same as hyperpnoea."
Under Causes, the article talks about how hyperventilation is not the same as hyperpnoea, yet clicking the link for hyperpnoea is just a redirect back to this article. In other words... the article is linking to itself... Furrybeagle (talk) 22:46, 26 March 2009 (UTC) hi, i just want to know more about hyperventilation and it's relation to dental office including ( cause-symptoms-mechanism-treatment) thanks

Solid Medical Evidence Related to Hyperventilation Is Necessary
Without specific numbers related to minute ventilation in healthy subjects, normal subjects, and in diseased states, the article about hyperventilation is nonsense. We should study science and provide public with hard core evidence (as in Evidence-based medicine), not some fantasies. (Artour2006 (talk) 10:41, 23 January 2011 (UTC)).


 * The table added appears to be original research synthesizing various minute ventilations from various conditions from disparate primary sources. I would much prefer a secondary source to add this information back in; as created, it isn't encyclopedic in nature anyways - we already describe the conditions that cause hyperventilation; adding a table with the exact minute ventilation from studies appears to place undue weight on the specific conditions noted and not on others. Yobol (talk) 15:40, 23 January 2011 (UTC)

In order to prove that this Table is "synthesizing various minute ventilations from various conditions from disparate primary sources", you need a small thing: find medical evidence or a single study that confirms that some group of patients with heart disease (of asthma, or diabetes, or CF, etc.) had nearly normal breathing parameters at rest (minute ventilation, or respiratory frequency, etc.). Then you can claim that this table is "synthesizing...".

Furthermore, we got here 4 medical doctors, who claim that this table are "from disparate primary sources" with "synthesizing" intentions. You, Yabol, in fact, claim that, for example, 3 doctors from Department of Cardiac Medicine, National Heart and Lung Institute, London, UK ""synthesized"" 88 patients with minute ventilation 15 (±4) L/min instead of normal 5-8 (or 6-7) L/min and then these medical ""synthesizers" published their original research in British Heart Journal (1995 Oct; 74(4): 377-380.)

Or a group of 7 Italian doctors from the Respiratory Function Laboratory, IRCCS, S. Maugeri Foundation, Montescano Medical Center, Pavia specially selected 132 patients with minute ventilation 12 (±3) l/min and published their synthesis in Chest (1998; 114; p. 1083-1090.)

All together, you are now blaming about 150 authors of over 50 peer-reviewed published medical studies that they deliberately selected sick patients with abnormally large minute ventilation and healthy subjects with normal minute volumes.

You are allowing yourself very strong claims, Yabol. (Artour2006 (talk) 10:21, 24 January 2011 (UTC)). (Artour2006 (talk) 10:19, 24 January 2011 (UTC)).


 * Moved this here as per WP:MEDRS

== Prevalence of hyperventilation == Minute ventilation or respiratory minute volume is the volume of air which is inhaled (inhaled minute volume) or exhaled (exhaled minute volume) from a person's lungs in one minute. Medical evidence suggests that hyperventilation is a common clinical finding for a variety of chronic health problems.

(Source: www.normalbreathing.com) There are many more medical studies that found 100% prevalence of chronic hyperventilation in patients with various chronic diseases and modern normal subjects.

Doc James (talk · contribs · email) 13:14, 24 January 2011 (UTC)

General Cleanup Tag: Syntax
Hi - This is just a quick note to say that I put the General Cleanup tag instead of making the change to the first sentence myself because the language is so convoluted that I can't quite make out what it means and am afraid I'd edit it incorrectly. Thanks! Sorry if I did anything incorrectly -- this is my first edit. :) NicoSuave (talk) 23:02, 24 May 2011 (UTC)

remove treament section
The treatment sectino as it stands is uselss and should be removed raher than left the way it is108.161.122.195 (talk) 04:20, 30 April 2012 (UTC)
 * I would say it should be left in but expanded and referenced, as it's an important medical condition. Td1wk (talk) 08:49, 30 April 2012 (UTC)

unsourced
Moved the content here per WP:PRESERVE as it is unsourced -- what is sourced i also moved as leavning it would be UNDUE:


 * Terminology

In very general terms, hyperventilation is an increased alveolar ventilation. Hyperventilation should not be confused with tachypnea (fast breathing) or hyperpnea (breathing that is faster or deeper than normal with an increased minute ventilation). Both of these terms neutrally describe the manner of breathing rather than the impact that breathing has on carbon dioxide levels. In tachypnea and hyperpnea, increased ventilation is appropriate for a metabolic acidotic state (also known as respiratory compensation) whereas in hyperventilation, increased ventilation is inappropriate for the metabolic state of blood plasma.

Exercise, fever, shivering, and other disorders can cause the body to produce more carbon dioxide than normal. The body attempts to correct for this by breathing more rapidly and deeply. This corrective behavior does not lead to excess ventilation. Rather, it brings the body into balance by compensating for excess carbon dioxide production. Thus, hyperpnea in this context is not hyperventilation. In fact, if the excess carbon dioxide production cannot be completely cast off via hyperpnea, then a person will in fact be hypoventilating even though they are breathing faster or more deeply than normal. For example, in certain respiratory disorders, the transfer of carbon dioxide from the blood to the alveoli may be blocked. No matter how deeply or rapidly the person tries to breathe, they cannot expel enough carbon dioxide.


 * from Causes

Hyperventilation can also occur when someone exercises over their VO2 max, when they're unable to generate sufficient energy through purely aerobic respiration, but hyperventilate in an effort to do so. The VO2 max is a representation of an individual's aerobic capacity during exercise of large duration and low intensity (from 30 minutes to hours), for example the marathon. It is the highest rate of oxygen consumption reached during maximum exertion in long duration exercises. If the intensity of exercise increases past an individual's VO2 max the consumption of oxygen will be relatively stabilized and the body will utilize anaerobic energy substrates, e.g. hepatic glycogen (a polysaccharide which stores glucose in the liver) through glycolysis, also known as passing the anaerobic threshold. As the result of the above-mentioned process there is an increase of lactic acid and carbon dioxide in the blood and therefore a decrease of the pH of the blood. Carbon dioxide is transported as bicarbonate ion through the blood during the gaseous exchange of oxygen and carbon dioxide between alveoli and blood capillaries through the respiratory membrane. The increase of the level of carbon dioxide in the blood reflects the more anaerobic metabolism past the anaerobic threshold by (Wasserman and Mclllory) and hence provokes the hyperventilation.

In normal breathing, both the depth and frequency of breaths are varied by the nervous system, primarily in order to maintain normal amounts of carbon dioxide but also to supply appropriate levels of oxygen to the body's tissues. This is mainly achieved by measuring the carbon dioxide content of the blood; normally, a high carbon dioxide concentration signals a low oxygen concentration, as we breathe in oxygen and breathe out carbon dioxide at the same time, and the body's cells use oxygen to burn fuel molecules, making carbon dioxide as a by-product. Normal minute ventilation is generally 5–8 liters of air per minute at rest for a 70 kg man.
 * Mechanism

If carbon dioxide levels are high, the body assumes that oxygen levels are low, and accordingly, the brain's blood vessels dilate to assure sufficient blood flow and supply of oxygen. Conversely, low carbon dioxide levels cause the brain's blood vessels to constrict, resulting in reduced blood flow to the brain and lightheadedness. The gases in the alveoli of the lungs are nearly in equilibrium with the gases in the blood. Normally, less than 10% of the gas in the alveoli is replaced with each breath taken. Deeper or quicker breaths as in hyperventilation exchange more of the alveolar gas with ambient air and have the net effect of expelling more carbon dioxide from the body, since the carbon dioxide concentration in normal air is very low. The resulting low concentration of carbon dioxide in the blood is known as hypocapnia. Since carbon dioxide is carried as bicarbonate in the blood, the loss of carbon dioxide will drive bicarbonate to combine with hydrogen ions (protons) to form more carbon dioxide. The loss of hydrogen ions results in the blood becoming alkaline, i.e. the blood pH value rises. This is known as a respiratory alkalosis.

This alkalization of the blood causes vessels to constrict (vasoconstriction). The high pH value resulting from hyperventilation also reduces the level of available calcium (hypocalcemia), which affects the nerves and muscles, causing constriction of blood vessels and tingling. This occurs because alkalization of the plasma proteins (mainly albumin) increases their calcium binding affinity, thereby reducing free ionized calcium levels in the blood. Therefore, low levels of carbon dioxide can cause tetany by altering the albumin binding of calcium such that the ionised (physiologically influencing) fraction of calcium is reduced.

Therefore, there are two main mechanisms that contribute to the cerebral vasoconstriction that is responsible for the lightheadedness, paresthesia, and fainting often seen with hyperventilation. One mechanism is that low carbon dioxide (hypocapnia) causes increased blood pH level (respiratory alkalosis), causing blood vessels to constrict. The other mechanism is that the alkalosis causes decreased freely ionized blood calcium, thereby causing cell membrane instability and subsequent vasoconstriction and paresthesia.

Hyperventilation can be useful in the management of head trauma. After head injuries, fluids can leak into the cranial vault, thus elevating intracranial pressure. Since the total cranial volume is relatively fixed, and the brain is much more compressible than the skull, in settings of increased intracranial pressure, the brain is preferentially compressed and damaged. Hyperventilation, and the resultant cerebral vasoconstriction, is useful in this situation, since it decreases the volume of blood in the brain. Less blood volume in the cranial cavity results in less pressure compressing the brain. However, this vasoconstriction comes at the cost of reducing blood flow to the brain, which can potentially result in ischemic damage.


 * Treatment

The first step that should be taken is to treat the underlying cause. If hypoxia is present supplemental oxygen may be useful. If it is due to anxiety as the cause of hyperventilation syndrome, counselling (such as cognitive behavioral therapy) to identify and address triggers may be useful, possibly supported by a few days of benzodiazepines. Mild hyperventilation can be treated by recycling some of the carbon dioxide released in one's breath. This is traditionally done by breathing into a paper bag. The Buteyko method will also reduce respiratory alkalosis in the short term and also claims to correct chronic hyperventilation by retraining the breathing pattern through repetitive breathing exercises although this is disputed.

-- Jytdog (talk) 00:49, 30 November 2016 (UTC)

Technique vs Condition
There is not enough balance in the article between the Technique vs Condition, for the moment it is 0% vs 100%. --TudorTulok (talk) 12:17, 13 May 2017 (UTC)