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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">akusherstvo</journal-id><journal-title-group><journal-title xml:lang="en">Obstetrics, Gynecology and Reproduction</journal-title><trans-title-group xml:lang="ru"><trans-title>Акушерство, Гинекология и Репродукция</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2313-7347</issn><issn pub-type="epub">2500-3194</issn><publisher><publisher-name>IRBIS LLC</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17749/2313-7347/ob.gyn.rep.2020.175</article-id><article-id custom-type="elpub" pub-id-type="custom">akusherstvo-887</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ORIGINAL ARTICLE</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНОЕ ИССЛЕДОВАНИЕ</subject></subj-group></article-categories><title-group><article-title>Parameters of neonate serum acid-base state and gas composition in multifetal pregnancy</article-title><trans-title-group xml:lang="ru"><trans-title>Показатели кислотно-основного состояния и газовый состав крови новорожденных при многоплодной беременности</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2658-5417</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Калашников</surname><given-names>С. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Kalashnikov</surname><given-names>S. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Калашников Сергей Аркадьевич – к.м.н., доцент кафедры акушерства и гинекологии педиатрического факультета</p><p>117997 Москва, ул. Островитянова, д. 1</p></bio><bio xml:lang="en"><p>Sergey A. Kalashnikov – MD, PhD, Associate Professor, Department of Obstetrics and Gynecology, Faculty of Pediatrics</p><p>1 Ostrovityanova Str., Moscow 117997</p></bio><email xlink:type="simple">homeksa@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГАОУ ВО «Российский национальный исследовательский медицинский университет имени Н.И. Пирогова» Министерства здравоохранения Российской Федерации</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Pirogov Russian National Research Medical University, Health Ministry of Russian Federation</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2020</year></pub-date><pub-date pub-type="epub"><day>10</day><month>01</month><year>2021</year></pub-date><volume>14</volume><issue>6</issue><fpage>612</fpage><lpage>621</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Kalashnikov S.A., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Калашников С.А.</copyright-holder><copyright-holder xml:lang="en">Kalashnikov S.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.gynecology.su/jour/article/view/887">https://www.gynecology.su/jour/article/view/887</self-uri><abstract><p>Aim: to study ABS parameters, blood gas composition and complete blood count in newborns upon multiple pregnancy depending on the order of twin birth, neonate weight, and accompanying chronic hypoxia. Materials and Methods. Laboratory parameters assessed in the twin-collected venous blood were analyzed: hemoglobin (Hb) and hematocrit (Ht) level, count of red blood cells (RBC), platelets (PLT) and white blood cells (WBC), base excess (BЕ), partial pressure of oxygen (рО2) and carbon dioxide (рСО2), оxygen saturation (sО2), standard and total carbon dioxide level (НСО–3, tСО2). Results. The second vs. first twin after vaginal delivery had decreased level of рН (7.30 ± 0.08 and 7.35 ± 0.09; р = 0.03, respectively), рО2 (18.2 ± 13.1 and 27.1 ± 10.7 mm Hg; р = 0.03), sО2 (29.7 ± 22.7 and 41.8 ± 20.3 %; р &lt; 0.001). Metabolic acidosis exacerbated in case of birth interval extending more than 30 minutes. The hypotrophic vs. normotrophic neonates had a decreased WBC (14.2 ±5.9 vs. 15.9 ± 6.5×109/L; р = 0.02), рО2 (19.3 ± 13.6 vs. 22.6 ± 10.6 mm Hg; р = 0.03), sО2 (27.9 ± 19.5 vs. 33.8 ± 20.6 %; р = 0.04). PH and PLT level were lower in newborns with intraventricular hemorrhages (7.29 ± 0.07 and 243.1 ± 75.4×109/L), whereas ВЕ magnitude was higher (–4.9 ± 5.2 mmol/L) than in those lacking intraventricular hemorrhages (7.34 ± 0.06; р = 0.03; 265.4 ±71.6×109/L; р &lt; 0.001; –3.2 ± 4.2 mmol/L; р = 0.02, respectively). Conclusion. During the vaginal delivery, a birth interval should not exceed 30 minutes. In case of diagnosing fetal growth retardation and hypoxia during pregnancy, caesarean section is an optimal option.</p></abstract><trans-abstract xml:lang="ru"><p>Введение. Показатели кислотно-основного состояния (КОС), газов крови и клинического анализа крови являются важным инструментом оценки состояния новорожденных, однако многие вопросы клинического применения этих показателей при многоплодии остаются мало изучены. Цель исследования: изучить показатели КОС, газов крови и клинического анализа крови новорожденных при многоплодной беременности в зависимости от порядка рождения близнецов, массы тела при рождении и наличия хронической гипоксии. Материалы и методы. У новорожденных из двоен проведен анализ лабораторных показателей венозной крови: уровней гемоглобина (Hb) и гематокрита (Ht), количества эритроцитов (RBC), тромбоцитов (PLT) и лейкоцитов (WBC), дефицита буферных оснований (ВЕ), парциального давления кислорода (рО2) и углекислого газа (рСО2), сатурации крови кислородом (sО2), стандартного бикарбоната (НСО–3), уровня тотальной углекислоты (tСО2). Результаты. При родоразрешении через естественные родовые пути у второго ребенка из двойни по сравнению с первым обнаружено снижение значений рН (7,30 ± 0,08 и 7,35 ± 0,09; р = 0,03, соответственно), рО2 (18,2 ± 13,1 и 27,1 ± 10,7 мм рт. ст.; р = 0,03) и sО2 (29,7 ± 22,7 и 41,8 ± 20,3 %; р &lt; 0,001). Метаболический ацидоз усугублялся, если интервал между рождением детей превышал 30 мин. Новорожденные с гипотрофией по сравнению с нормотрофиками имели более низкое число лейкоцитов (14,2 ± 5,9 и 15,9 ± 6,5×109/л; р = 0,02), показатели рО2 (19,3 ± 13,6 и 22,6 ± 10,6 мм рт. ст.; р =0,03) и sО2 (27,9 ± 19,5 и 33,8 ± 20,6 %; р = 0,04). У детей с внутрижелудочковыми кровоизлияниями значения рН и количество тромбоцитов были ниже (7,29 ± 0,07 и 243,1 ± 75,4×109/л), а дефицит оснований больше (–4,9 ± 5,2 ммоль/л), чем у детей без внутрижелудочковых кровоизлияний (7,34± 0,06; р = 0,03; 265,4 ± 71,6×109/л; р &lt; 0,001; –3,2 ± 4,2 ммоль/л; р= 0,02, соответственно). Заключение. При родоразрешении через естественные родовые пути интервал между рождением детей не должен превышать 30 мин. При задержке развития плода/плодов и гипоксии во время беременности оптимальной является операция кесарева сечения.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>перинатальный исход</kwd><kwd>интервал между рождением детей</kwd><kwd>газовый состав крови</kwd><kwd>кислотно-основное состояние</kwd></kwd-group><kwd-group xml:lang="en"><kwd>perinatal outcome</kwd><kwd>birth interval</kwd><kwd>blood gas composition</kwd><kwd>acid-base state</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Коваленко Т.С., Чечнева М.А., Капустина М.В. и др. Истмико-цервикальная недостаточность при многоплодной беременности. Российский вестник акушера-гинеколога. 2018;1(18):44–50. https://doi.org/10.17116/rosakush201818144-50.</mixed-citation><mixed-citation xml:lang="en">Kovalenko T.S., Chechneva M.A., Kapustina M.V. et al. Isthmic-cervical insufficiency in multiple pregnancies. 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