Okujwayelekile, okwandisiwe, nokwehlisa imiphumela ye-V / Q
Ukungahambi kahle kwe-V / Q kuyinhlawulo eyenzeka emaphashini lapho umoya wokuphuza umoya (ukushintshaniswa komoya phakathi kwamaphaphu nemvelo) kanye ne-perfusion (ukuhamba kwegazi emaphashini) akuhambisani ngokufanayo, uphawu olujwayelekile lwe-chronic obstructive disease pulmonary ( COPD ).
Yisho ukuthini i-V / Q
Ngaphambi kokuxoxa ngalokho okwenzeka ku-V / Q okungahambi kahle, kubalulekile ukuchaza ngokuqondile ukuthi i-V / Q isho ukuthini:
- I-V imele umoya wokuvuthwa umoya , umoya ophefumula ngemphunga nasemlonyeni, phansi nge-trachea, ube yi-bronchi, bese uhamba ngezindiza ezincane ezindiza emigwaqweni encane kunazo zonke ezibizwa ngokuthi i-alveoli lapho ukushintshaniswa kwe-oxygen ne-carbon dioxide kwenzeka khona .
- I-Q imele ukumiswa noma ukugeleza kwegazi. Kusuka enhliziyweni, i-deoxygenated ("igazi eliluhlaza okwesibhakabhaka") lidlula emithanjeni ye-pulmonary (efana nemithanjeni ngoba inegazi elidinga oksijeni) ngezitsha ezincane nezincane kanye nama- capillari (imithwalo yegazi encane kunazo zonke) lapho i-oksijeni ne-exchange exchange ithatha indawo.
I- alveoli yiyona encane kunazo zonke zokuhamba emoyeni, isisodwa esisodwa esincane. Eceleni ne-alveoli kukhona i-capillary, emincane kakhulu emithanjeni yegazi kanye nesisindo esisodwa kuphela. Lona indawo lapho ukushintshaniswa kwe-oksijeni nekhabhoni kwenzeka emaphashini, njengoba kudlula oksijeni ukusuka e-alveoli kuya kuma-capillaries, futhi i-carbon dioxide idlula kuma-capillaries kuya e-alveoli.
I-V / Q noma i-ventilation / perfusion ibhekisela emkhathini womoya ofinyelela e-alveoli ehlukaniswe inani legazi eligeleza ngama-capillari emaphashini.
Ukuqonda Isikhala Esifile
Kubalulekile ekulandelayo ukuchaza "indawo efile." Lokhu kubhekisela kunoma yimuphi indawo lapho i-alveoli ne-capillaire ingaboni khona.
Lesi sikhala esifile singaba:
- Isikhala esibulalayo esine-anatomical, okubangelwa ukuvinjelwa kwe-airways noma ukunikezwa kwegazi, njengokungenwa kwe-pulmonary emboli (ukuvimbela umkhumbi wegazi) noma umzimba wangaphandle uhanjiswe endleleni (ukuvimbela umoya).
- Isikhala esiphelile sezinto eziphilayo, okwenzeka lapho izakhiwo ze-airways noma imithwalo yegazi zivamile, kodwa kunezinye izizathu zokuthi kungani ama-alveoli ne-capillari engavumelani nokujula kwegazi kude nomunye wamaphaphu (ukuvimbela umzimba) .
Ngesikhala esiphelile, ubhekene nokuletha igazi endaweni engakwazi ukuyithatha i-oxygen, noma ukuletha umoya endaweni engakwazi ukukhipha umoya-mpilo.
Ukulinganisa isilinganiso se-V / Q
Ukulinganisa isilinganiso se-V / Q senziwa ngezivivinyo ezimbili ezihlukene. Ukulinganisa umoya, umuntu unomaski obeke phezu kobuso bakhe futhi uphefumule emoyeni omsakazo. Ukuze ulinganise i-perfusion, iphrotheni enomsakazo ijojowe ku-vein. Khona-ke imiphumela yalezi zivivinyo ezimbili ifaniswa.
Yisho ukuthini okushiwo yi-V / Q
I-V / Q i-mismatch isho ukuthi kwezinye izindawo zamapayipi, i-alveoli ne-capillari ayihlanganisi noma isikhala esifile. Lokhu kungasho ukuthi kwezinye izindawo zamapayipi, kunezinhlamvu eziningi kune-alveoli, ngamanye amagama, izindawo emaphashini angcono aphethwe yigazi kunokungena umoya.
Kwezinye izindawo, kungase kube khona i-alveoli eningi nge-oksijeni elisha kunama-capillari ukuze athole lelo-oxygen. Ngamanye amazwi, ezinye izindawo zamapayipi zingase zibe ngcono umoya ongcono kunokuba zenziwe kabi.
Okunye ukungahambisani kahle kwenzeka ngokujwayelekile, kodwa uma kukhula ngaphezu kwephuzu elithile, kubangela izinkinga. Kungani i-V / Q ixosha inkinga? Ukungahambi kahle kwe-V / Q yisona esivame kakhulu se- hypoxemia kanye nengxenye yezimbangela eziningi zokuhluleka ukuphefumula.
I-hypoxemia yigama elisho izinga elinciphile le-oksijini egazini. Lapho amangqamuzana omzimba enqatshelwe oksijini (futhi ewonakele futhi ekugcineni afe) ngenxa ye-hypoxemia, kuthiwa yi-hypoxia.
Izimpawu zika-hypoxia zingase zibe ukuphelelwa amandla, ukuphefumula, ukudideka, futhi uma kungaphenduliwe, ukufa.
Izimbangela ze-V / Q
Ukungahambi kahle kwe-V / Q kungabangelwa yilokho okwandisa noma ukunciphisa umoya wokuphuza amaphaphu noma ukwanda noma ukunciphisa ukukhipha amaphaphu. Ngamanye amazwi, noma yini ephazamisa ikhono lomoya omusha ukufinyelela e-alveoli, noma noma yini evimbela igazi ukugeleza kuma-capillaries. Zombili lezi zingaphazamisa ibhalansi phakathi kwe-ventilation ne-perfusion.
Ukujwayelekile, ukwehlisa, nokwandiswa kwe-V / Q Izilinganiso
Isilinganiso esijwayelekile se-V / Q siseduze no-0.80. Lokhu kusho ukuthi cishe amalitha amane e-oksijeni adlula emaphashini ngomzuzu ngamunye kanti ama-5 amalitha wegazi adlula emaphashini.
Ukwenyuka kwe-V / Q isilinganiso kwenzeka uma kukhona ukwehla kwamandla emaphashini noma ukwanda kwamaphutha (ukugeleza kwegazi okungaphezulu kumaphaphu). Izimo ezingabangela ukwehla kwe-V / Q zihlanganisa:
- I-bronchitis engapheliyo : Ukuhlanganiswa kwe- bronchospasm , ama-plugs, izibhamu, nokuvimbelwa kwemimoya konke kuhlanganisa ukungena kwe-air condition futhi kunciphise izinga lokuphuza umoya.
- I-asthma
- I-edema yepulmonary
- Ukuvinjelwa kwe-Airway (isifiso somzimba wangaphandle)
Ukwenyuka kwezinga le-V / Q kwenzeka uma kukhona ukungena kwempuphu noma ukunciphisa kwe-perfusion (ukugeleza kwegazi kuya emaphashini.) Ukwenyuka kwezinga le-V / Q kungabonakala nge:
- Ukubumbana kwepulmonary: Ukuvuthwa kwe-pulmonary is a clot igazi emaphashini ngokuvamile aqala njengendwangu yegazi emilenzeni ephumula bese ehamba eya emaphashini. Uma kukhulu ngokwanele, i-clot ingavimba isitsha esiphelele segazi okwenza kungabi namaphutha ezindaweni ezithile zamaphaphu ezithola umoya. Ngakho-ke i-V / Q iyanda ngenxa yokuthi umoya wokuvuthwa (V) uhlala okufanayo futhi ukukhipha (Q) kwehla. Kulayini lwe-V / Q, kuyoba nobufakazi bokuthi izingxenye zamaphaphu ekusatshalaliswa kwegazi elichaphazelekayo azenzi kahle.
- I-Emphysema : I-Emphysema ingabangela futhi isilinganiso esiphezulu se-V / Q. Ngenxa ye-alveoli ewonakele futhi ebhujiswe emaphashini, indawo ekhona yokudluliselwa kwe-oxygen ne-carbon dioxide iyahla. Ngakho-ke umoya we-ventilation uyakhuphuka, okwenza kube nesilinganiso se-V / Q esandisiwe.
Imithombo:
UJobe, B., McCurry, C., Morissette, M. et al. Impact of Inflammation, Emphysema, nokuyeka ukubhema ku-V / Q kumamodeli wamouse we-Lung Obstructing. Ucwaningo lokuphefumula . 2014. 15:42.
Ilabhulali Kazwelonke Yezokwelapha yase-US. I-MedlinePlus. I-Pulmonary Ventilation / Scan Scan. https://www.nlm.nih.gov/medlineplus/ency/article/003828.htm.