查看“︁阴离子间隙”︁的源代码

[[File:阴离子间隙.jpg|thumb|简略示意阴离子间隙的计算，UA指未测定的阴离子，UC指未测定的阳离子，'''AG'''指阴离子间隙。]]
'''阴离子间隙'''（{{lang|en|anion gap}}, AG）是指[[血浆]]中未测定的[[阴离子]]（undetermined anion, UA）和未测定的[[阳离子]]的差值（undetermined cation, UC）的差值，即<math>AG = UA - UC</math>。<ref name=":0">{{cite book |author1=肖献忠 |title=病理生理学 |date=2018-11-30 |publisher=高等教育出版社 |isbn=978-7-04-050887-1 |page=49 |edition=4th |accessdate=2024-11-12}}</ref>“阴离子间隙”也可能指代[[血清]]阴离子间隙、[[尿液]]阴离子间隙。<ref>{{Cite book |url=https://www.ncbi.nlm.nih.gov/books/NBK539757/ |title=StatPearls |last=Pandey |first=Devansh G. |last2=Sharma |first2=Sandeep |date=2024 |publisher=StatPearls Publishing |location=Treasure Island (FL) |chapter=Biochemistry, Anion Gap |pmid=30969579 |quote=There are three types: serum, plasma, and urine anion gaps. |access-date=2024-11-30 |archive-date=2024-12-01 |archive-url=https://web.archive.org/web/20241201074748/https://www.ncbi.nlm.nih.gov/books/NBK539757/ |dead-url=no }}</ref>

== 计算 ==
Na<sup>+</sup>是血浆中主要的阳离子，又称可测定的阳离子；HCO<sub>3</sub><sup>-</sup>和Cl<sup>-</sup>是血浆中主要的阴离子，又称可测定的阴离子。未测定的阳离子（UC）主要包括K<sup>+</sup>，Ca<sup>2+</sup>，Mg<sup>2+</sup>等，未测定的阴离子主要包括[[蛋白质|Pr]]<sup>-</sup>（蛋白质陰離子），HPO<sub>4</sub><sup>2-</sup>，SO<sub>4</sub><sup>2-</sup>。<ref name=":0" />由此可见，阴离子间隙是血浆钠浓度（体内主要阳离子）与氯离子和[[碳酸氢盐]]浓度（体内主要阴离子）之和之间的差值。<ref>{{cite journal |last1=Wiener |first1=Sage W. |title=Toxicologic Acid-Base Disorders |journal=Emergency Medicine Clinics of North America |date=2014-02 |volume=32 |issue=1 |pages=149–165 |doi=10.1016/j.emc.2013.09.011 |accessdate=2024-11-30}}</ref>即<ref>{{cite journal |last1=Carroll |first1=Robert G. |title=Integration |journal=Elsevier's Integrated Physiology |date=2007 |pages=209–214 |doi=10.1016/B978-0-323-04318-2.50023-6 |accessdate=2024-11-30}}</ref><ref>{{Cite book |url=http://www.crossref.org/deleted_DOI.html |title=Cardiothoracic Critical Care |last=Gillham |first=Michael |last2=Sidebotham |first2=David |date=2007 |publisher=Elsevier |isbn=978-0-7506-7572-7 |pages=461–469 |language=en |chapter=Acid-Base Disturbances |doi=10.1016/b978-075067572-7.50034-5 |access-date=2024-12-05 |archive-date=2014-01-28 |archive-url=https://web.archive.org/web/20140128105109/http://www.crossref.org/deleted_DOI.html |dead-url=no }}</ref>：<math>AG = Na^+ - (Cl^- + HCO_3^-)</math>
{{Test sample values|align=right}}

== 临床意义 ==

阴离子间隙实际上反映了血浆（或血清）中固定酸根（如[[硫酸盐]]、[[磷酸盐]]和[[乳酸盐]]等）的含量，而实验检查通常并不直接测定这些固定酸根的含量。<ref name=":1">{{Cite book |title=Understanding Pathophysiology |last=Sue E. Huether MS, Kathryn L. McCance MS |isbn=978-0323639088 |edition=7th |pages=332}}</ref>由于阴离子间隙很容易从常规实验室检查结构中计算得到，因此经常被用作代谢性酸中毒，特别是[[高乳酸血症]]的筛查。<ref>{{Cite journal |last=Dinh |first=C H |last2=Ng |first2=R |last3=Grandinetti |first3=A |last4=Joffe |first4=A |last5=Chow |first5=D C |title=Correcting the anion gap for hypoalbuminaemia does not improve detection of hyperlactataemia |url=https://emj.bmj.com/lookup/doi/10.1136/emj.2005.031898 |journal=Emergency Medicine Journal |language=en |date=2006-08-01 |volume=23 |issue=8 |doi=10.1136/emj.2005.031898 |issn=1472-0205 |pmc=2564167 |pmid=16858097}}</ref>

血浆阴离子间隙的正常值约为10-14mmol/L<ref name=":0" />，升高的阴离子间隙可用于判断[[代谢性酸中毒]]是由于内源性或外源性酸的增加所致（是否为AG增高型代谢性酸中毒），如当硫酸盐、磷酸盐、乳酸盐或水杨酸根产生增多或排出减少时，阴离子间隙增大。<ref name=":1" /><ref name=":0" />阴离子间隙降低的情况可见于[[低白蛋白血症]]等UC增加或UA减少的情况。<ref name=":0" />

== 历史 ==
Emmet和Narins最早于1977年使用阴离子间隙来解释和诊断代谢性酸中毒的病因。<ref>{{Cite journal |last=Emmett |first=Michael |last2=Narins |first2=Robert G. |title=CLINICAL USE OF THE ANION GAP: |url=http://journals.lww.com/00005792-197756010-00002 |journal=Medicine |language=en |date=1977-01 |volume=56 |issue=1 |doi=10.1097/00005792-197756010-00002 |issn=0025-7974}}</ref><ref>{{Cite journal |last=Chawla |first=Lakhmir S |last2=Shih |first2=Shirley |last3=Davison |first3=Danielle |last4=Junker |first4=Christopher |last5=Seneff |first5=Michael G |title=Anion gap, anion gap corrected for albumin, base deficit and unmeasured anions in critically ill patients: implications on the assessment of metabolic acidosis and the diagnosis of hyperlactatemia |url=https://bmcemergmed.biomedcentral.com/articles/10.1186/1471-227X-8-18 |journal=BMC Emergency Medicine |language=en |date=2008-12 |volume=8 |issue=1 |doi=10.1186/1471-227X-8-18 |issn=1471-227X |pmc=2644323 |pmid=19087326 |access-date=2024-12-05 |archive-date=2024-11-30 |archive-url=https://web.archive.org/web/20241130065001/https://bmcemergmed.biomedcentral.com/articles/10.1186/1471-227X-8-18 |dead-url=no }}</ref>

==参考文献==
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