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Guttorm Haugen - One of the best experts on this subject based on the ideXlab platform.

  • the effect of a maternal meal on fetal Liver Blood Flow
    PLOS ONE, 2019
    Co-Authors: Gun Lisbeth Opheim, Tore Henriksen, Guttorm Haugen
    Abstract:

    INTRODUCTION During the third trimester of development, the human fetus accumulates fat, an important energy reservoir during the early postnatal period. The fetal Liver, perfused by the nutrient-rich and well-oxygenated Blood coming directly from the placenta, is assumed to play a central role in these processes. Earlier studies have linked fetal Liver Blood Flow with maternal nutritional status and response to the maternal oral glucose tolerance test. Our aim was to explore the effect of a regular maternal meal on fetal Liver Blood Flow at two timepoints during the third trimester, representing the start and towards the end of the fetal fat accretion period. We also sought to explore the influence of prepregancy body mass index on how the maternal meal affects fetal Liver Blood Flow. METHODS Using ultrasound Doppler, we examined 108 healthy women with singleton pregnancies in gestational weeks 30 and 36. At each visit, the first examination was performed with the participant in a fasting state at 08.30 a.m., followed by a standard breakfast meal of approximately 400 kcal. The examination was repeated after 105 minutes. Umbilical vein and ductus venosus Blood Flow was estimated from diameter and Blood Flow velocity measurements. Fetal Liver Flow was calculated as umbilical vein Flow minus ductus venosus Flow, and change in Liver Blood Flow as Flow after minus before the meal. The total group was divided into a normal-weight group (prepregancy body mass index 18.5-25.0 kg/m2; n = 83) and an overweight group (prepregancy body mass index >25.0 kg/m2; n = 21). Four women with prepregancy body mass index <18.5 kg/m2 were excluded from these analyses. Non-parametric statistical hypothesis tests were used for group comparisons. RESULTS For the total group, we observed a significant increase in median (10th - 90th percentile) Liver Flow 28.9 (‒67.9-111.6) ml/min (p = 0.002) following the meal in week 36, but not in week 30, ‒2.63 (‒53.2-65.0) ml/min (p = 0.91). This result in turn yielded a statistically significant increase in delta Liver Flow from weeks 30 to 36 of 26.0 (‒107.1-146.6) ml/min (p = 0.008). The increase in postprandial Liver Flow was observed only in the normal-weight group in week 36. Accordingly, the delta Liver Flow values between the two weight groups were significantly different in week 36 (p = 0.006) but not in week 30 (p = 0.155). Among the normal-weight women, the increase in delta Liver Blood Flow from weeks 30 to 36 was 39.3 (‒83.0-156.1) ml/min (p<0.001); in contrast, we observed no statistically significant change in the overweight group (‒44.5 (‒229.0-123.2) ml/min; p = 0.073). As a substitute for Liver size, we divided the delta Liver Flow values by abdominal circumference and found no changes in the statistical significance results within or between the two weight groups. CONCLUSION In our healthy study population, we observed a statistically significant difference in Liver Blood Flow after maternal intake of a regular meal. This effect depended on gestational age and maternal prepregancy body mass index, but apparently was independent of Liver size, based on abdominal circumference as a proxy measure.

  • human fetoplacental and fetal Liver Blood Flow after maternal glucose loading a cross sectional observational study
    Acta Obstetricia et Gynecologica Scandinavica, 2014
    Co-Authors: Tore Henriksen, Guttorm Haugen, Jens Bollerslev
    Abstract:

    Objective To study umbilical vein and fetal Liver Blood Flow related to fetal anthropometric measures following maternal oral glucose loading. Design Experimental design in a cross-sectional observational study. Setting University hospital. Population A total of 113 low-risk pregnancies (30–32 weeks of gestation). Methods Ultrasound Doppler measurements of umbilical vein and ductus venosus Blood Flow (ml/min) before and 2 h after completed 75-g oral glucose tolerance test (OGTT). Liver Blood Flow was defined as the umbilical vein Blood Flow minus ductus venosus Blood Flow. Main outcome measures Changes in umbilical vein and fetal Liver Blood Flow following OGTT related to fetal biometric measurements. Results In the fasting state, fetal abdominal circumference z-scores did not correlate with any of the Flow parameters; 120 min after glucose loading, the z-scores correlated positively with the changes in umbilical vein (r = 0.25, p = 0.010) and fetal Liver Blood Flow (r = 0.25, p = 0.009), but not with those in ductus venosus (p = 0.84). In simultaneous multiple linear regression analyses, the effects of the changes in umbilical vein or fetal Liver Blood Flow after OGTT on the fetal abdominal circumference z-scores were almost equal to or greater than other parameters related to fetal size (body mass index, fasting plasma glucose, parity, and sex). Fetal heart rate increased after OGTT, but did not influence the association between the Blood Flow parameters and fetal abdominal circumference z-scores. Conclusions Changes in umbilical vein and fetal Liver Blood Flow after glucose loading were positively related to fetal abdominal size.

  • fetal Liver Blood Flow distribution role in human developmental strategy to prioritize fat deposition versus brain development
    PLOS ONE, 2012
    Co-Authors: Keith M Godfrey, Guttorm Haugen, Torvid Kiserud, Hazel Inskip, C Cooper, Nicholas C Harvey, S R Crozier, S M Robinson
    Abstract:

    Among primates, human neonates have the largest brains but also the highest proportion of body fat. If placental nutrient supply is limited, the fetus faces a dilemma: should resources be allocated to brain growth, or to fat deposition for use as a potential postnatal energy reserve? We hypothesised that resolving this dilemma operates at the level of umbilical Blood distribution entering the fetal Liver. In 381 uncomplicated pregnancies in third trimester, we measured Blood Flow perfusing the fetal Liver, or bypassing it via the ductus venosus to supply the brain and heart using ultrasound techniques. Across the range of fetal growth and independent of the mother's adiposity and parity, greater Liver Blood Flow was associated with greater offspring fat mass measured by dual-energy X-ray absorptiometry, both in the infant at birth (r = 0.43, P<0.001) and at age 4 years (r = 0.16, P = 0.02). In contrast, smaller placentas less able to meet fetal demand for essential nutrients were associated with a brain-sparing Flow pattern (r = 0.17, p = 0.02). This Flow pattern was also associated with a higher degree of shunting through ductus venosus (P = 0.04). We propose that humans evolved a developmental strategy to prioritize nutrient allocation for prenatal fat deposition when the supply of conditionally essential nutrients requiring hepatic inter-conversion is limited, switching resource allocation to favour the brain if the supply of essential nutrients is limited. Facilitated placental transfer mechanisms for glucose and other nutrients evolved in environments less affluent than those now prevalent in developed populations, and we propose that in circumstances of maternal adiposity and nutrient excess these mechanisms now also lead to prenatal fat deposition. Prenatal developmental influences play important roles in the human propensity to deposit fat.

Tore Henriksen - One of the best experts on this subject based on the ideXlab platform.

  • the impact of umbilical vein Blood Flow and glucose concentration on Blood Flow distribution to the fetal Liver and systemic organs in healthy pregnancies
    The FASEB Journal, 2020
    Co-Authors: Gun Lisbet Opheim, Ane Moe Holme, Maia Blomhoff Holm, Trond M Michelsen, Saba Muneer Zahid, Marie Cecilie Paasche Roland, Tore Henriksen
    Abstract:

    Glucose is a major energy substrate for the fetus, including Liver, heart, and brain metabolism. The umbilical vein (UV) Blood Flow supplies the fetal Liver directly from the placenta, whereas a fraction is shunted via ductus venosus (DV) to the fetal systemic circulation bypassing the fetal Liver. We hypothesized UV glucose concentration to be a major regulator of the distribution of glucose supply between the fetal Liver and DV, and explored the influence of maternal metabolic status on this distribution. We included 124 healthy women with normal singleton pregnancies, scheduled for elective cesarean section. UV and DV Blood Flow measurements were performed by Doppler ultrasound immediately before, and Blood samples were obtained during surgery. UV Blood Flow was significantly correlated with DV Blood Flow, Liver Blood Flow, and the DV shunting fraction, while UV glucose concentration was not. For normal-weight mothers, the maternal-fetal glucose gradient was positively correlated with DV shunting fraction, and negatively with Liver Blood Flow. For the fetuses of the overweight mothers no such correlation was found. This indicates that within the normal physiological range the human fetus makes adaptations of Blood Flow to ensure individual needs related to the offered maternal energy supply.

  • the effect of a maternal meal on fetal Liver Blood Flow
    PLOS ONE, 2019
    Co-Authors: Gun Lisbeth Opheim, Tore Henriksen, Guttorm Haugen
    Abstract:

    INTRODUCTION During the third trimester of development, the human fetus accumulates fat, an important energy reservoir during the early postnatal period. The fetal Liver, perfused by the nutrient-rich and well-oxygenated Blood coming directly from the placenta, is assumed to play a central role in these processes. Earlier studies have linked fetal Liver Blood Flow with maternal nutritional status and response to the maternal oral glucose tolerance test. Our aim was to explore the effect of a regular maternal meal on fetal Liver Blood Flow at two timepoints during the third trimester, representing the start and towards the end of the fetal fat accretion period. We also sought to explore the influence of prepregancy body mass index on how the maternal meal affects fetal Liver Blood Flow. METHODS Using ultrasound Doppler, we examined 108 healthy women with singleton pregnancies in gestational weeks 30 and 36. At each visit, the first examination was performed with the participant in a fasting state at 08.30 a.m., followed by a standard breakfast meal of approximately 400 kcal. The examination was repeated after 105 minutes. Umbilical vein and ductus venosus Blood Flow was estimated from diameter and Blood Flow velocity measurements. Fetal Liver Flow was calculated as umbilical vein Flow minus ductus venosus Flow, and change in Liver Blood Flow as Flow after minus before the meal. The total group was divided into a normal-weight group (prepregancy body mass index 18.5-25.0 kg/m2; n = 83) and an overweight group (prepregancy body mass index >25.0 kg/m2; n = 21). Four women with prepregancy body mass index <18.5 kg/m2 were excluded from these analyses. Non-parametric statistical hypothesis tests were used for group comparisons. RESULTS For the total group, we observed a significant increase in median (10th - 90th percentile) Liver Flow 28.9 (‒67.9-111.6) ml/min (p = 0.002) following the meal in week 36, but not in week 30, ‒2.63 (‒53.2-65.0) ml/min (p = 0.91). This result in turn yielded a statistically significant increase in delta Liver Flow from weeks 30 to 36 of 26.0 (‒107.1-146.6) ml/min (p = 0.008). The increase in postprandial Liver Flow was observed only in the normal-weight group in week 36. Accordingly, the delta Liver Flow values between the two weight groups were significantly different in week 36 (p = 0.006) but not in week 30 (p = 0.155). Among the normal-weight women, the increase in delta Liver Blood Flow from weeks 30 to 36 was 39.3 (‒83.0-156.1) ml/min (p<0.001); in contrast, we observed no statistically significant change in the overweight group (‒44.5 (‒229.0-123.2) ml/min; p = 0.073). As a substitute for Liver size, we divided the delta Liver Flow values by abdominal circumference and found no changes in the statistical significance results within or between the two weight groups. CONCLUSION In our healthy study population, we observed a statistically significant difference in Liver Blood Flow after maternal intake of a regular meal. This effect depended on gestational age and maternal prepregancy body mass index, but apparently was independent of Liver size, based on abdominal circumference as a proxy measure.

  • human fetoplacental and fetal Liver Blood Flow after maternal glucose loading a cross sectional observational study
    Acta Obstetricia et Gynecologica Scandinavica, 2014
    Co-Authors: Tore Henriksen, Guttorm Haugen, Jens Bollerslev
    Abstract:

    Objective To study umbilical vein and fetal Liver Blood Flow related to fetal anthropometric measures following maternal oral glucose loading. Design Experimental design in a cross-sectional observational study. Setting University hospital. Population A total of 113 low-risk pregnancies (30–32 weeks of gestation). Methods Ultrasound Doppler measurements of umbilical vein and ductus venosus Blood Flow (ml/min) before and 2 h after completed 75-g oral glucose tolerance test (OGTT). Liver Blood Flow was defined as the umbilical vein Blood Flow minus ductus venosus Blood Flow. Main outcome measures Changes in umbilical vein and fetal Liver Blood Flow following OGTT related to fetal biometric measurements. Results In the fasting state, fetal abdominal circumference z-scores did not correlate with any of the Flow parameters; 120 min after glucose loading, the z-scores correlated positively with the changes in umbilical vein (r = 0.25, p = 0.010) and fetal Liver Blood Flow (r = 0.25, p = 0.009), but not with those in ductus venosus (p = 0.84). In simultaneous multiple linear regression analyses, the effects of the changes in umbilical vein or fetal Liver Blood Flow after OGTT on the fetal abdominal circumference z-scores were almost equal to or greater than other parameters related to fetal size (body mass index, fasting plasma glucose, parity, and sex). Fetal heart rate increased after OGTT, but did not influence the association between the Blood Flow parameters and fetal abdominal circumference z-scores. Conclusions Changes in umbilical vein and fetal Liver Blood Flow after glucose loading were positively related to fetal abdominal size.

Catherijne A J Knibbe - One of the best experts on this subject based on the ideXlab platform.

  • pilot study on the influence of Liver Blood Flow and cardiac output on the clearance of propofol in critically ill patients
    European Journal of Clinical Pharmacology, 2008
    Co-Authors: Mariska Y M Peeters, Leon Aarts, Ferenc A Boom, Leo Bras, Dick Tibboel, Meindert Danhof, Catherijne A J Knibbe
    Abstract:

    Objective To investigate the effect of cardiac output and Liver Blood Flow on propofol concentrations in critically ill patients in the intensive care unit. Methods Five medical/surgical critically ill patients were enrolled in this preliminary study. Liver Blood Flow was measured using sorbitol. The cardiac output was measured by bolus thermodilution. NONMEM ver. V was applied for propofol pharmacokinetic analysis. Results The clearance of propofol was positively influenced by the Liver Blood Flow (P<0.005), whereas no significant correlation between cardiac output and propofol clearance was found. A correlation between Liver Blood Flow and cardiac output or cardiac index could not be assumed in this patient group. Conclusions Liver Blood Flow is a more predictive indicator than cardiac output for propofol clearance in critically ill patients when the techniques of hepatic sorbitol clearance and bolus thermodilution, respectively, are used. Further study is needed to determine the role played by Liver Blood Flow and cardiac output on the pharmacokinetics of highly extracted drugs in order to reduce the observed high interindividual variabilities in response in critically ill patients.

Torvid Kiserud - One of the best experts on this subject based on the ideXlab platform.

  • fetal Liver Blood Flow distribution role in human developmental strategy to prioritize fat deposition versus brain development
    PLOS ONE, 2012
    Co-Authors: Keith M Godfrey, Guttorm Haugen, Torvid Kiserud, Hazel Inskip, C Cooper, Nicholas C Harvey, S R Crozier, S M Robinson
    Abstract:

    Among primates, human neonates have the largest brains but also the highest proportion of body fat. If placental nutrient supply is limited, the fetus faces a dilemma: should resources be allocated to brain growth, or to fat deposition for use as a potential postnatal energy reserve? We hypothesised that resolving this dilemma operates at the level of umbilical Blood distribution entering the fetal Liver. In 381 uncomplicated pregnancies in third trimester, we measured Blood Flow perfusing the fetal Liver, or bypassing it via the ductus venosus to supply the brain and heart using ultrasound techniques. Across the range of fetal growth and independent of the mother's adiposity and parity, greater Liver Blood Flow was associated with greater offspring fat mass measured by dual-energy X-ray absorptiometry, both in the infant at birth (r = 0.43, P<0.001) and at age 4 years (r = 0.16, P = 0.02). In contrast, smaller placentas less able to meet fetal demand for essential nutrients were associated with a brain-sparing Flow pattern (r = 0.17, p = 0.02). This Flow pattern was also associated with a higher degree of shunting through ductus venosus (P = 0.04). We propose that humans evolved a developmental strategy to prioritize nutrient allocation for prenatal fat deposition when the supply of conditionally essential nutrients requiring hepatic inter-conversion is limited, switching resource allocation to favour the brain if the supply of essential nutrients is limited. Facilitated placental transfer mechanisms for glucose and other nutrients evolved in environments less affluent than those now prevalent in developed populations, and we propose that in circumstances of maternal adiposity and nutrient excess these mechanisms now also lead to prenatal fat deposition. Prenatal developmental influences play important roles in the human propensity to deposit fat.

  • venous Liver Blood Flow and regulation of human fetal growth evidence from macrosomic fetuses
    American Journal of Obstetrics and Gynecology, 2011
    Co-Authors: Jorg Kessler, Keith M Godfrey, Svein Rasmussen, Mark A Hanson, Torvid Kiserud
    Abstract:

    OBJECTIVE: Experimental studies show that fetal Liver venous perfusion is a determinant for growth in utero. Here we explore the relationship between fetal venous Blood Flow to the Liver and macrosomia. STUDY DESIGN: From diameter and Blood Flow velocity measurements, we derived Liver venous Blood Flow in a longitudinal ultrasound study of 25 macrosomic fetuses of nondiabetic mothers during the second half of pregnancy. RESULTS: Compared with appropriately growing fetuses, macrosomic fetuses directed more umbilical Blood to the Liver tissue, with correspondingly less contribution from the portal circulation when normalized for fetal weight. Whereas total venous Liver Blood Flow showed no late gestation rise in the reference population, it continued to increase in macrosomic fetuses and was accompanied by greater fetal weight. CONCLUSION: The direct relationship between venous Liver Blood Flow and macrosomia in the fetus supports the concept that intrauterine growth is linked to the amount and distributional pattern of venous Liver perfusion.

Mariska Y M Peeters - One of the best experts on this subject based on the ideXlab platform.

  • pilot study on the influence of Liver Blood Flow and cardiac output on the clearance of propofol in critically ill patients
    European Journal of Clinical Pharmacology, 2008
    Co-Authors: Mariska Y M Peeters, Leon Aarts, Ferenc A Boom, Leo Bras, Dick Tibboel, Meindert Danhof, Catherijne A J Knibbe
    Abstract:

    Objective To investigate the effect of cardiac output and Liver Blood Flow on propofol concentrations in critically ill patients in the intensive care unit. Methods Five medical/surgical critically ill patients were enrolled in this preliminary study. Liver Blood Flow was measured using sorbitol. The cardiac output was measured by bolus thermodilution. NONMEM ver. V was applied for propofol pharmacokinetic analysis. Results The clearance of propofol was positively influenced by the Liver Blood Flow (P<0.005), whereas no significant correlation between cardiac output and propofol clearance was found. A correlation between Liver Blood Flow and cardiac output or cardiac index could not be assumed in this patient group. Conclusions Liver Blood Flow is a more predictive indicator than cardiac output for propofol clearance in critically ill patients when the techniques of hepatic sorbitol clearance and bolus thermodilution, respectively, are used. Further study is needed to determine the role played by Liver Blood Flow and cardiac output on the pharmacokinetics of highly extracted drugs in order to reduce the observed high interindividual variabilities in response in critically ill patients.