{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,7]],"date-time":"2026-11-07T09:14:57Z","timestamp":1794042897951,"version":"4.8.0"},"reference-count":22,"publisher":"BMJ","issue":"4","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Arch Dis Child Fetal Neonatal Ed"],"accepted":{"date-parts":[[2016,10,13]]},"published-print":{"date-parts":[[2017,7]]},"abstract":"<jats:sec>\n                  <jats:title>Objective<\/jats:title>\n                  <jats:p>While delayed umbilical cord clamping (UCC) is thought to facilitate placental to infant blood transfusion, the physiological factors regulating flow in the umbilical arteries and veins during delayed UCC is unknown. We investigated the effects of gravity, by changing fetal height relative to the placenta, and ventilation on umbilical blood flows and the cardiovascular transition during delayed UCC at birth.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>Catheters and flow probes were implanted into preterm lambs (128\u2005days) prior to delivery to measure pulmonary, carotid, umbilical artery (UaBF) and umbilical venous (UvBF) blood flows. Lambs were placed either 10\u2005cm below or 10\u2005cm above the ewe. Ventilation commenced 2\u20133\u2005min before UCC and continued for 30\u2005min after UCC.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Gravity reduced umbilical and cerebral flows when lambs were placed below the midline, but the reduction in UaBF and UvBF was similar. Ventilation during delayed UCC reduced UvBF and UaBF by similar amounts, irrespective of the lamb's position, such that flows into and out of the placenta remained balanced. The effects of ventilation on umbilical flows were much greater than the effects of gravity, but no net placental to lamb blood transfusion could be detected under any condition. Cardiovascular parameters, cerebral oxygen kinetics and final blood volumes were similar in both groups 5\u2005min after UCC.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>Gravity caused small transient effects on umbilical and cerebral flow, but given changes were similar in umbilical arteries and veins, no net placental transfusion was detected. Ventilation during delayed UCC has a markedly greater influence on cardiovascular function in the newborn.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1136\/archdischild-2016-311159","type":"journal-article","created":{"date-parts":[[2016,11,9]],"date-time":"2016-11-09T07:24:39Z","timestamp":1478676279000},"page":"F312-F319","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":35,"title":["Effect of body position and ventilation on umbilical artery and venous blood flows during delayed umbilical cord clamping in preterm lambs"],"prefix":"10.1136","volume":"102","author":[{"given":"Stuart B","family":"Hooper","sequence":"first","affiliation":[{"name":"Ritchie Centre, The Hudson Institute for Medical Research, Clayton, Victoria, Australia"},{"name":"Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kelly J","family":"Crossley","sequence":"additional","affiliation":[{"name":"Ritchie Centre, The Hudson Institute for Medical Research, Clayton, Victoria, Australia"},{"name":"Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valerie A","family":"Zahra","sequence":"additional","affiliation":[{"name":"Ritchie Centre, The Hudson Institute for Medical Research, Clayton, Victoria, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeroen","family":"van Vonderen","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Leiden University Medical Centre, Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alison","family":"Moxham","sequence":"additional","affiliation":[{"name":"Ritchie Centre, The Hudson Institute for Medical Research, Clayton, Victoria, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew W","family":"Gill","sequence":"additional","affiliation":[{"name":"Centre for Neonatal Research and Education, The University of Western Australia, Crawley, Western Australia, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Kluckow","sequence":"additional","affiliation":[{"name":"Department of Neonatology, Royal North Shore Hospital and University of Sydney, Sydney, New South Wales, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arjan B","family":"te Pas","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Leiden University Medical Centre, Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Euan M","family":"Wallace","sequence":"additional","affiliation":[{"name":"Ritchie Centre, The Hudson Institute for Medical Research, Clayton, Victoria, Australia"},{"name":"Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Graeme R","family":"Polglase","sequence":"additional","affiliation":[{"name":"Ritchie Centre, The Hudson Institute for Medical Research, Clayton, Victoria, Australia"},{"name":"Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2016,11,8]]},"reference":[{"key":"2025090511323395000_102.4.F312.1","doi-asserted-by":"publisher","DOI":"10.1016\/j.resuscitation.2015.07.045"},{"key":"2025090511323395000_102.4.F312.2","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1016\/S0140-6736(69)90213-X","article-title":"Effect of gravity on placental transfusion","volume":"2","author":"Yao","year":"1969","journal-title":"Lancet"},{"key":"2025090511323395000_102.4.F312.3","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2012.250084"},{"key":"2025090511323395000_102.4.F312.4","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0117504"},{"key":"2025090511323395000_102.4.F312.5","doi-asserted-by":"publisher","DOI":"10.1136\/archdischild-2014-307144"},{"key":"2025090511323395000_102.4.F312.6","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(14)60197-5"},{"key":"2025090511323395000_102.4.F312.7","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.ph.41.030179.002123"},{"key":"2025090511323395000_102.4.F312.8","unstructured":"Dawes GS . Foetal and neonatal physiology: a comparative study of the changes at birth. Chicago: Year Book Medical Publishers, Inc., 1968."},{"issue":"2","key":"2025090511323395000_102.4.F312.9","first-page":"11","article-title":"Fetal and neonatal pulmonary circulation","volume":"115","author":"Rudolph","year":"1977","journal-title":"Am Rev Respir Dis"},{"key":"2025090511323395000_102.4.F312.10","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2009.174870"},{"key":"2025090511323395000_102.4.F312.11","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.01544.2005"},{"key":"2025090511323395000_102.4.F312.12","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00041.2008"},{"key":"2025090511323395000_102.4.F312.13","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1046\/j.1537-2995.1999.39299154729.x","article-title":"Measurement of red cell survival using biotin-labeled red cells: validation against 51 Cr-labeled red cells","volume":"39","author":"Mock","year":"1999","journal-title":"Transfusion"},{"key":"2025090511323395000_102.4.F312.14","doi-asserted-by":"crossref","first-page":"1178","DOI":"10.1111\/j.1537-2995.2009.02095.x","article-title":"Red blood cell volume can be independently determined in vitro using sheep and human red blood cells labeled at different densities of biotin","volume":"49","author":"Mock","year":"2009","journal-title":"Transfusion"},{"key":"2025090511323395000_102.4.F312.15","doi-asserted-by":"publisher","DOI":"10.1016\/j.jpeds.2013.10.041"},{"key":"2025090511323395000_102.4.F312.16","doi-asserted-by":"crossref","first-page":"1389","DOI":"10.1113\/JP270926","article-title":"Increase in Pulmonary blood flow at birth: role of oxygen and lung aeration","volume":"594","author":"Lang","year":"2016","journal-title":"J Physiol"},{"key":"2025090511323395000_102.4.F312.17","doi-asserted-by":"publisher","DOI":"10.1159\/000368880"},{"key":"2025090511323395000_102.4.F312.18","doi-asserted-by":"publisher","DOI":"10.1038\/jp.2009.170"},{"key":"2025090511323395000_102.4.F312.19","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2005-1706"},{"key":"2025090511323395000_102.4.F312.20","doi-asserted-by":"publisher","DOI":"10.1136\/adc.2006.108837"},{"key":"2025090511323395000_102.4.F312.21","doi-asserted-by":"publisher","DOI":"10.1016\/S1474-4422(08)70294-1"},{"key":"2025090511323395000_102.4.F312.22","doi-asserted-by":"publisher","DOI":"10.1159\/000240691"}],"container-title":["Archives of Disease in Childhood - Fetal and Neonatal Edition"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/archdischild-2016-311159","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T18:53:51Z","timestamp":1757098431000},"score":1,"resource":{"primary":{"URL":"https:\/\/fn.bmj.com\/lookup\/doi\/10.1136\/archdischild-2016-311159"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,11,8]]},"references-count":22,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2017,6,21]]},"published-print":{"date-parts":[[2017,7]]}},"alternative-id":["10.1136\/archdischild-2016-311159"],"URL":"https:\/\/doi.org\/10.1136\/archdischild-2016-311159","relation":{},"ISSN":["1359-2998","1468-2052"],"issn-type":[{"value":"1359-2998","type":"print"},{"value":"1468-2052","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,11,8]]}}}