{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T17:23:03Z","timestamp":1786123383496,"version":"build-2736575974"},"reference-count":35,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"1","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,1]]},"abstract":"<jats:sec>\n                    <jats:title>BACKGROUND:<\/jats:title>\n                    <jats:p>\n                      General anesthesia during pregnancy is not uncommon, for example, for trauma surgery, cerclage, or cesarean delivery. Current recommendations are to maintain maternal partial pressure of carbon dioxide in arterial blood (p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      ) at 30 mm Hg, which is based solely on the average maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      in awake pregnant women. However, there is no evidence that this target, compared to other targets, would enable optimal conditions for the fetus during general anesthesia. Maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      can affect uterine blood flow, affinity of hemoglobin for oxygen, and fetal CO\n                      <jats:sub>2<\/jats:sub>\n                      elimination. In this study, a range of potential targets of maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      was investigated in the ovine model, aiming to determine which target is most conducive to physiological fetal blood gas values during laparotomy with general anesthesia.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>METHODS:<\/jats:title>\n                    <jats:p>\n                      Ten time-mated pregnant Swifter ewes with a gestational age of 93 to 104 days were used. During the first phase of the experiment, anesthesia was induced, all ewes were ventilated to target a physiological maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      of 30 mm Hg, a maternal laparotomy was performed, and a fetal microcatheter was inserted surgically to enable blood sampling from the fetal aorta. Thereafter, in the second phase of the experiment, the 10 pregnant ewes were randomized to 10 different targets of maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      between 27 and 50 mm Hg (1 target for each ewe), and maternal ventilation was adjusted accordingly. Forty-five minutes later, maternal and fetal arterial blood gas samples were analyzed. Linear regression models were used to estimate maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      enabling physiologic fetal parameters, including fetal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      (primary outcome).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS:<\/jats:title>\n                    <jats:p>\n                      A maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      of 27.4 mm Hg (95% confidence interval, 23.1\u201330.3) enabled physiological fetal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      . Each increase in maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      by 1 mm Hg, on average, increased fetal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      by 0.94 mm Hg (0.69\u20131.19). This relationship had a strong correlation (r\u00b2 = 0.906). No fetuses died during the experiment.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS:<\/jats:title>\n                    <jats:p>\n                      This study provides experimental support for the clinical recommendation to maintain maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      close to the physiologic value of 30 mm Hg during general anesthesia for maternal laparotomy in pregnancy as it is conducive to physiological fetal blood gas values. Given the lower bound of the 95% confidence interval, the possibility that a lower maternal p\n                      <jats:sub>a<\/jats:sub>\n                      CO\n                      <jats:sub>2<\/jats:sub>\n                      would improve fetal gas exchange cannot be excluded.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1213\/ane.0000000000006872","type":"journal-article","created":{"date-parts":[[2024,11,25]],"date-time":"2024-11-25T15:01:50Z","timestamp":1732546910000},"page":"175-184","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":0,"title":["Optimal Maternal Ventilation During Laparotomy with General Anesthesia in Pregnancy in the Ovine Model"],"prefix":"10.1213","volume":"140","author":[{"given":"Tom","family":"Bleeser","sequence":"first","affiliation":[{"name":"Department of Anesthesiology, UZ Leuven, Leuven, Belgium"},{"name":"Department of Cardiovascular Sciences, Group 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Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Basurto","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, UZ Leuven, Leuven, Belgium"},{"name":"Department of Development and Regeneration, Cluster Woman and Child, Group Biomedical Sciences, KU Leuven, Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ignacio","family":"Valenzuela","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, UZ Leuven, Leuven, Belgium"},{"name":"Department of Development and Regeneration, Cluster Woman and Child, Group Biomedical Sciences, KU Leuven, Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Talia Rose","family":"Hubble","sequence":"additional","affiliation":[{"name":"Department of Clinical Medicine, Medical Sciences Division, University of Oxford, Oxford, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yada","family":"Kunpalin","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, UZ Leuven, Leuven, Belgium"},{"name":"Department of Development and Regeneration, Cluster Woman and Child, Group Biomedical Sciences, KU Leuven, Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Doaa","family":"Emam","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, UZ Leuven, Leuven, Belgium"},{"name":"Department of Development and Regeneration, Cluster Woman and Child, Group Biomedical Sciences, KU Leuven, Leuven, Belgium"},{"name":"Department of Obstetrics and Gynecology, University Hospitals Tanta, Tanta, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marc","family":"Van de Velde","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, UZ Leuven, Leuven, Belgium"},{"name":"Department 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