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| {{Unreferenced|date=June 2013}}
| | Im Conrad and was born on 19 January 1977. My hobbies are Trainspotting and Bus spotting.<br><br>Feel free to visit my web-site [http://durl.me/7czh3k food And beverage Pr crier pr] |
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| {{Infobox disease|
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| Name = Respiratory alkalosis |
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| Image = Davenport Fig 11.jpg |
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| Caption = [[Davenport diagram]] |
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| DiseasesDB = 406 |
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| ICD10 = {{ICD10|E|87|3|e|70}} |
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| ICD9 = {{ICD9|276.3}} |
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| ICDO = |
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| OMIM = |
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| MedlinePlus = 000111 |
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| eMedicineSubj = med |
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| eMedicineTopic = 2009 |
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| MeshID = D000472 |
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| }}
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| '''Respiratory alkalosis''' is a medical condition in which increased respiration ([[hyperventilation]]) elevates the blood [[pH]] (a condition generally called [[alkalosis]]). It is one of four basic categories of disruption of [[acid-base homeostasis]].
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| ==Terminology==
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| *'''Alkalosis''' refers to disorders that elevate cellular pH to > 7.45.
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| *'''Alkalemia''' refers to a arterial pH > 7.45.
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| ==Types==
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| There are two types of respiratory alkalosis: [[chronic (medicine)|chronic]] and [[acute (medicine)|acute]].
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| * ''Acute respiratory alkalosis'' occurs rapidly. For every 10 mmHg drop in PCO<sub>2</sub> in arterial blood, there is a corresponding 2 mEq/L drop in bicarbonate ion due to acute compensation. During acute respiratory alkalosis, the person may lose consciousness where the rate of ventilation will resume to normal.
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| * ''Chronic respiratory alkalosis'' is a more long-standing condition. For every 10 mmHg drop in PCO<sub>2</sub> in arterial blood, there is a corresponding 5 mEq/L drop in bicarbonate ion. The drop of 5 mEq/L of bicarbonate ion is a compensation effect which reduces the alkalosis effect of the drop in PCO<sub>2</sub> in blood. This is termed metabolic compensation.
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| ==Mechanism==
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| Respiratory alkalosis generally occurs when some stimulus (see "Causes" below) makes a person hyperventilate. The increased breathing produces increased [[alveoli|alveolar]] respiration, expelling [[Carbon dioxide|CO<sub>2</sub>]] from the circulation. This alters the dynamic [[chemical equilibrium]] of carbon dioxide in the circulatory system, and the system reacts according to [[Le Chatelier's principle]]. Circulating hydrogen ions and bicarbonate are shifted through the [[carbonic acid]] (H<sub>2</sub>CO<sub>3</sub>) intermediate to make more CO<sub>2</sub> via the enzyme [[carbonic anhydrase]] according to the following reaction:
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| :<math>\rm HCO_3^- + H^+ \rightarrow H_2CO_3 \rightarrow CO_2 + H_2O</math>
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| The net result of this is decreased circulating hydrogen ion concentration, and thus increased [[pH]] (alkalosis). There is also a decrease in ionized blood [[calcium]] concentration.
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| ===Causes===
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| Respiratory alkalosis may be produced accidentally ([[iatrogenic]]ally) during excessive [[mechanical ventilation]]. Other causes include:
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| * [[psychiatry|psychiatric]] causes: [[anxiety]], [[hysteria]] and [[Stress (medicine)|stress]]
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| * [[Central nervous system|CNS]] causes: [[stroke]], [[subarachnoid hemorrhage|subarachnoid haemorrhage]], [[meningitis]]
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| * drug use: [[doxapram]], [[aspirin]], [[caffeine]] and [[coffee]] abuse
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| * moving into [[high altitude]] areas, where the low [[atmospheric pressure]] of oxygen stimulates increased ventilation
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| * lung disease such as [[pneumonia]], where a [[hypoxic drive]] governs breathing more than CO<sub>2</sub> levels (the normal determinant)
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| * [[fever]], which stimulates the respiratory centre in the brainstem
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| * [[pregnancy]]
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| * high levels of NH4+ leading to brain swelling and decreased blood flow to the brain
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| ==Symptoms==
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| Symptoms of respiratory alkalosis are related to the decreased blood carbon dioxide levels, and include peripheral [[paraesthesiae]]. In addition, the alkalosis may disrupt calcium ion balance, and cause the symptoms of [[hypocalcaemia]] (such as [[tetany (medical sign)|tetany]] and [[fainting]]) with no fall in total serum calcium levels.
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| ==In popular culture==
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| In ''[[The Andromeda Strain]]'', [[Michael Crichton]]'s first novel, only two people exposed to a pathogenic extraterrestrial microbe survive. Scientists investigating these survivors discover that each had abnormal blood pH. One, a baby, had respiratory alkalosis due to constant crying; the other, an old man, drinks [[Sterno]]. As a result, it becomes clear that the microbe cannot survive outside a narrow pH range.
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| ==See also==
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| * [[Metabolic acidosis]]
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| * [[Metabolic alkalosis]]
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| * [[Respiratory acidosis]]
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| * [[Hypocalcemia]]
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| {{Fluid, electrolyte, acid base metabolic pathology}}
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| [[Category:Acid-base disturbances]]
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Im Conrad and was born on 19 January 1977. My hobbies are Trainspotting and Bus spotting.
Feel free to visit my web-site food And beverage Pr crier pr