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Hyperventilation and the Body

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Hyperventilation and the Body Hyperventilation and the body C. Gilbert Hyperventilation has rapid and far-ranging physiological effects via its alteration of pH and depletion of CO 2 in the body, resulting in respiratory alkalosis, acute or chronic. The general effects on skeletal and smooth muscles, as well as neural tissue, are summarized. A wide variety of symptoms such as pain, tension, disturbances of consciousness, circulatory problems and cardiovascular effects can confound treatment efforts but may respond to alterations of breathing patterns. Suggestions are given for detecting this condition. Introduction Background Imagine the following set of symptoms reported The 'Fat folder' syndrome is one vivid description to you: episodes of light-headedness attached by Claude Lum to the so-called accompanied by cool, moist hands, pale skin, hyperventilation syndrome, indicating the perhaps some tunnel vision, chest pain, tortuous, and tortured, doctor-to-doctor path headaches, feelings of unreality, dread and followed by many individuals pursuing relief agitation; heart palpitations, uncomfortable from their problems. Each specialist performs his breathing and tender shoulder muscles. Suppose tests, finds little that is specifically diagnostic, and that medical consultation has found little of note, dutifully relays the individual on to the next but at least there is no evidence of major disease. specialist because typically, with this disorder, Where would you start? A break for lunch, symptoms come and go in many different perhaps? systems. Hyperventilation simply means breathing in Christopher Gilbert In working with such a diffuse set of PhD Social Sciences complaints spread out over many systems, a excess of the body's needs for oxygen at a and Human practitioner will naturally tend to focus on the particular moment. The need fluctuates Services, Ramapo symptom that is most familiar and easiest to continuously, and the body gets what it needs by College of New Jersey, Mahwah, handle, and may postpone dealing with the rest adjusting respiratory rate and depth. Strong, NJ 07430, USA of the picture in the hopes that perhaps vigorous breathing, no matter how fast or deep, is Correspondence everything will clear up in time, or that someone not necessarily hyperventilatory unless it is in to: C. Gilbert, else will handle the other problems. You may excess of the body's needs. 10 Wilsey Square #14, Ridgewood, receive a referral because you hold out promise of The problem in hyperventilation is not 'too NJ 07450, USA helping with the muscle pain or the headaches. much oxygen' - whatever is unabsorbed by the Manuscript But other things are probably happening as well. lungs is simply exhaled again. The problem accepted: The problem, in the example above, may comes with a deficit of CO 2. CO2 is a waste gas, a April 1998 actually be an intermittent biochemical byproduct of metabolism, primarily muscle This article was derangement brought on by insufficient carbon activity; it is given off by tissues and carried in previously published in dioxide (CO2) in the blood, resulting in broad the bloodstream to the lungs, to be exhaled. Journal of effects on every organ and nearly every bodily Production of CO 2 is normally in equilibrium Bodywork and system. Even though there is no clear indication with 0 2 intake. Movement Therapies 2(3): of overbreathing at that moment, it may be This equilibrium is important because CO2 has 184-191 correct to consider hyperventilation. an essential physiological function, remarkable 130 Acddent & Emergency Nursing (1999) 7, 130-140 9 1999 Harcourt Brace & Company Ltd Hyperventilation and the body considering that it's on its way to being excreted: present moment but in some other moment more it is a prime regulator of vascular tone in the associated with frustration, anxiety, or anger. In cerebral cortex, among other places. This is such a case time and place are blurred as the Nature's elegant solution: in a natural memory or imagination stimulates the body to environment and assuming normal physiology, prepare for action: fight, flight, or tense-freeze. CO 2 builds up in the bloodstream only with All these options require muscle contraction, breath-holding or while breathing oxygen-poor which requires oxygen, so hyperventilation air. In either case, high blood CO 2 correlates with becomes a sensible precautionary preparation. less oxygen available. Since oxygen deficit Apart from this reality-shifting effect, events (hypoxia) is dangerous to the brain, several actually occurring in the present moment may mechanisms combine in such a circumstance to not really require any physical action: for maintain normal brain oxygenation, and instance, when one's hypercritical supervisor is vasodilation of blood vessels is one of them. This coming to inspect your work and you are is probably due to alterations in calcium and/or preparing for a confrontation that requires only phosphorus movement through the vessel walls. words, not fists. Here there will be a discrepancy Arterial walls, when dilated, become more between the action-demands on the body and the permeable to oxygen molecules. mind's expectation of trouble. Apparently the possibility of threat of any kind, social or The loophole physical, reliably sets off physical preparation 'just in case'. Hyperventilation is part of this, The opposite condition, however, is more more for some individuals than others. Also, relevant to this article. There seems to be a there is evidence that the hyperventilation can loophole, or flaw, in the system, possibly unique easily be conditioned (Ley 1999) so that a to humans: although high CO 2 stimulates stimulus associated with potential danger will vasodilatation and increased oxygenation, a drop trigger more breathing directly, just as Pavlov's in CO 2 stimulates vasoconstriction and in fact is dogs came to salivate to the sound of a bell. said to be the 'most potent vasoconstrictive agent Hyperventilation is functional as long as known' (Raichle & Plum 1972). This other half of muscle use follows closely after; the resulting a regulatory mechanism becomes rapidly reserve of oxygen and loss of CO 2 permit a head dysfunctional as CO 2 concentration in the blood start if danger should materialize. The regulatory drops, and that is what happens when an mechanisms for breathing probably evolved individual breathes in excess of bodily needs for without providing for the possibility that oxygen: more CO 2 is exhaled than is being hyperventilation might occur at times other than replaced. The degree of circulatory loss in the preparing for action. When emotional arousal cerebral cortex is around 2% for each I mmHg does not lead to physical action, it can leave the drop in CO 2 pressure (Gardner 1996) This loss is brain and body impaired by alkalosis because visible to an observer if the hyperventilating respiration is driven to a higher level than is individual's cortex happens to be uncovered at required by the current situation. The muscles are the time; it has been described by neurosurgeon not generating enough CO 2 to replace what is Wilder Penfield as a blanching of the surface of being exhaled; the organism is not active when the brain. the system expects it to be. Thus body and mind Normal arterial carbon dioxide tension can live in two different worlds, and this odd (PaCO2) is around 40 mmHg. A level of 30 mismatch can create a morass of symptoms and corresponds to pH of 7.5; this is the commonly- no end of distress (Table 1). accepted point at which mild hypocapnic symptoms are likely to begin.Twenty mmHg is Importance of pH associated with a pH of 7.6, at which symptoms will appear in almost everyone. The body takes pains to preserve a normal pH in Response to 'needs of the moment' may the body, particularly in the bloodstream, constitute one thing to the body but quite another extracellular fluids and cerebrospinal fluid. The thing to the mind, at least in human beings. For body is optimized for a pH of 7.4, slightly above instance, an individual can be mentally not in the the neutral 7.0, toward the alkaline end. This 1999 Harcourt Brace & Company Ltd Accident and Emergency Nursing (1999) 7, 130-140 131 Hyperventilation and the body Table 1 Notable acute effects of hyperventilation Effects on smooth muscle Generally, vasoconstriction and spasm Gastrointestinal: tight throat, difficulty swallowing, intestinal cramps Restricted circulation in cerebral cortex (leads to light-headedness, dizziness, visual disturbances) Cold hands and feet Impaired coronary artery blood flow Effects on skeletal muscle Weakness, fatigue, twitching Heart muscle disturbance (palpitations, skipped beats, rapid pulse) Vague shifting pains, especially around chest Diaphragm weakness, impaired breathing Tense or fatigued neck and shoulder muscles (from over use during thoracic breathing) Effects on nervous system Peripheral tingling, numbness Hypersensitivity to lights and sounds Faster reflexes Enhanced sympathetic activity (more adrenaline) Common psychological effects Panic, fear of death Restlessness, heightened vigilance Time distortion, depersonalization, derealization Misinterpretation of symptoms (catastrophic thinking, hypochondria) supports endocrine, metabolic and other combination of high pH and low CO 2 causes maintenance operations. Deviations in pH of a certain body changes. Acute, episodic tenth of a point have noticeable consequences for hyperventilation is often associated with an the body, changing nerve conduction, the emotional crisis, either current or relived. In the diameter of blood vessels and the contractility of stereotype, hyperventilation is seen as a panic smooth muscle. 'attack' - dramatic and obvious, but ameliorated We can easily disrupt this balance with 2 or 3 by letting time pass or by breathing into a paper deep breaths, pH will rise from 7.4 to 7.5 or 7.6, bag. This is actually much less common than and CO 2 will fall from a normal 40 to 30 or 25 in subtle, chronic hyperventilation. In this case, less than 30 seconds (Figs 1 & 2).
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