Yiziphi izici zokujikeleza kwegazi ebusweni?
Ngakho-ke, igazi eliphethe i-oksijeni kumntwana, liza kuye ngqo kusuka e-placenta ngokusebenzisa umvuthwandaba. Lesi sifo emgqeni we-umbilical, kanye nemibhoshongo emibili ye-umbilical, ithwala igazi ku-fetus kusuka e-placenta.
Khona-ke, emzimbeni wesisu, i-velilical vein ihlukaniswe ngamagatsha amabili: umgwaqo we-venous (arantzium), ohambisa igazi elibhebhethekayo ngqo kwi-inferior vena cava, lapho ixubene khona; egatsheni lesibili - igazi likamama ligeleza ngesistimu ye-vein ngqo ngaphakathi kwesibindi se-fetus, lapho kuhlanzwa khona izinto ezinobuthi.
Ngenxa yalokho, ngokusabalalisa kwegazi e-placental ye-fetus, ixubane igazi kusuka e-vena cava elingaphansi lingena endaweni efanele yomntwana, futhi i-venous one ivela emthanjeni ophezulu. Ukusuka ku-atrium elungile kuya kwi-ventricle efanele ithola ingxenye encane yegazi, eliya kumbuthano omncane wokujikeleza nge-trum pulmonary. Nguye onika izicubu zamaphaphu, i-tk. amaphaphu esiswini sikamama ayisebenzi.
Yimaphi amafomu akhona ohlelweni lokujikeleza kwesisu?
Ngemva kokuhlola uhlelo lokujikeleza kwegazi lwe-fetus, kuyadingeka ukuthi ukhulume ngokuthi kukhona khona okunye okusebenzayo, okungajwayelekile ukuthi umntwana ozelweyo akakho.
Ngakho kule septum, ephakathi kwe-atria, kukhona imbobo - iwindi elinesibindi. Ngaye, igazi elixutshwe, edlulisa umjikelezo omncane, liwela ngokushesha ku-atrium kwesokunxele, lapho ligeleza khona ku-ventricle kwesokunxele. Khona-ke ukugeleza kwegazi kuya e-aorta, ibe yindilinga enkulu. Ngakho-ke kunomyalezo wemibuthano engu-2 yokusakaza kwe-fetal.
Futhi ohlelweni lokujikeleza lwe-fetus, ukubunjwa okusebenzayo kuvelele, njengezimpi zomgwaqo. Uxhuma isiqu se-pulmonary emgqeni we-aorta, futhi uyenezela ingxenye ethile yegazi elixutshwe. Ngamanye amazwi, ibutho lomzila, kanye nefasitela le-oval, lilayisha umjikelezo omncane wegazi, ukuqondisa igazi ngqo kumbuthano omkhulu.
Isistimu yokujikeleza ishintsha kanjani emva kokuzalwa?
Kusukela ngesikhathi sokuphefumula kwengane, kusukela ekuzalweni kwakhe, umjikelezo omncane wokujikeleza kwegazi uqala ukusebenza. Emva kokuzalwa kwengane kuboshwe ngezintambo zomzimba, uhlelo lokujikeleza kwegazi lwe-fetus nomama luphela. Kulesi simo, ukusabalalisa kwe-placental kumiswa ngokuphelele futhi i-veillical vein ayinalutho. Lokhu kuholela ekunciphiseni okukhulu ekucindezelweni emgodleni we-atrium efanele kanye nokunyuka kwe-atrium kwesokunxele, njenge. yilapho igazi lithunyelwa kusuka kumbuthano omncane. Ngenxa yalokho, ngenxa yalokhu umehluko wecindezelo, i-valve window ye-oval igaxa ngokwayo. Uma lokhu kungenzeki, khona-ke ingane itholakale inenkinga yokuzalwa, ngoba kukhona ingxube yegazi elinomsoco negazi,
Ngokuqondene namathanga aseBatalov nase-Arancian, ayekhona ekusakazeni kwe-intrauterine ye-fetus, ngokuzenzekelayo, ngokoqobo ngasekupheleni kwenyanga yokuqala yokuphila, iziqu. Ngenxa yalokho, umntwana, njengomuntu omdala, uqala ukusebenza imibuthano engu-2 yokujikeleza. Kodwa-ke, naphezu kwalokhu, usana lunezici ezithile zesistimu yokujikeleza, ehambisana nokusebenza kwezitho kanye nezinhlelo. Ngakho-ke, uhlelo lwezinhliziyo zomvuthwandaba, olulodwa lwezokuqala emva kokuzalwa, luhlolwa yi-ultrasound.