TY - JOUR
T1 - Effects of reductions in hemoglobin-oxygen affinity and hematocrit level on oxygen consumption and acid-base state in fetal lambs
AU - Edelstone, Daniel I.
AU - Darby, Marilyn J.
AU - Bass, Katherine
AU - Miller, Kim
N1 - Funding Information:
From the Department of Obstetrics and G_~necology, University of Pittsburgh School of Medicine. Supported by grants from the NatIOnal Institute of Health (HD19092) and the Magee-Womens Hospital Research Fund. Presented by tnvttation at the Seventh Annual Meeting of the Amer-Ican Gynecological and Obstetncal Society, Napa, Californza. Sep-tember 8-10, 1988. Reprint requests: Daniel I. Edelstone, MD. Department ofObstetncs and Gynecology, Magee-Womens Hospital, Forbes Ave. & Halket St., Pittsburgh, PA 15213.
Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1989/4
Y1 - 1989/4
N2 - To determine whether the high oxygen affinity of fetal blood, compared with that of the adult, is advantageous to the fetus during fetal anemia we studied 16 chronically catheterized fetal lambs. Half of the lambs had hemoglobin-oxygen affinity reduced acutely by isovolemic exchange transfusion with fresh adult whole blood; the other half served as controls. In both groups of fetuses, we measured fetal oxygen delivery, oxygen consumption, and acid-base state at normal fetal hematocrit levels and during reductions in the hematocrit level of 30% (moderate anemia) and 60% (severe anemia) produced by isovolemic exchange transfusions with plasma. At normal fetal hematocrit levels, reductions in hemoglobin-oxygen affinity had no effect on fetal oxygen consumption or acid-base state. During moderate anemia, fetal oxygen delivery decreased in both series of fetuses, but oxygen consumption and base excess fell only in those fetuses whose circulations contained adult hemoglobin. During severe anemia, oxygen consumption and base excess decreased in both groups of fetuses, although these changes were more pronounced in fetuses with adult hemoglobin than in those with fetal hemoglobin. Our data indicate that, even though a high hemoglobin-oxygen affinity may not be essential to a healthy fetus, it is critical for normal metabolism in a fetus subjected to a hypoxic stress such as anemia.
AB - To determine whether the high oxygen affinity of fetal blood, compared with that of the adult, is advantageous to the fetus during fetal anemia we studied 16 chronically catheterized fetal lambs. Half of the lambs had hemoglobin-oxygen affinity reduced acutely by isovolemic exchange transfusion with fresh adult whole blood; the other half served as controls. In both groups of fetuses, we measured fetal oxygen delivery, oxygen consumption, and acid-base state at normal fetal hematocrit levels and during reductions in the hematocrit level of 30% (moderate anemia) and 60% (severe anemia) produced by isovolemic exchange transfusions with plasma. At normal fetal hematocrit levels, reductions in hemoglobin-oxygen affinity had no effect on fetal oxygen consumption or acid-base state. During moderate anemia, fetal oxygen delivery decreased in both series of fetuses, but oxygen consumption and base excess fell only in those fetuses whose circulations contained adult hemoglobin. During severe anemia, oxygen consumption and base excess decreased in both groups of fetuses, although these changes were more pronounced in fetuses with adult hemoglobin than in those with fetal hemoglobin. Our data indicate that, even though a high hemoglobin-oxygen affinity may not be essential to a healthy fetus, it is critical for normal metabolism in a fetus subjected to a hypoxic stress such as anemia.
KW - Fetal anemia
KW - P
KW - critical fetal oxygen delivery
KW - exchange transfusion with adult blood cells
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U2 - 10.1016/0002-9378(89)90297-4
DO - 10.1016/0002-9378(89)90297-4
M3 - Article
C2 - 2712115
AN - SCOPUS:0024566987
SN - 0002-9378
VL - 160
SP - 820
EP - 828
JO - American journal of obstetrics and gynecology
JF - American journal of obstetrics and gynecology
IS - 4
ER -