The Experts below are selected from a list of 45 Experts worldwide ranked by ideXlab platform
William E. Hoffman - One of the best experts on this subject based on the ideXlab platform.
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Cerebral venous and tissue gases and arteriovenous shunting in the dog.
Anesthesia and analgesia, 1999Co-Authors: Guy Edelman, William E. HoffmanAbstract:UNLABELLED: Cerebral venous blood gas values have been used to indicate Brain tissue oxygenation. However, it is not clear how cerebral tissue and venous measures may vary under physiologic conditions caused by arteriovenous shunt. The purpose of this study was to measure Brain tissue and local cerebral venous oxygen (PO2) and carbon dioxide (P(CO2)) partial pressure during changes in ventilation and to calculate shunt fraction. Eight dogs were anesthetized with isoflurane. After a craniotomy, a Neurotrend probe (Diametrics Inc., St. Paul, MN) that measures P(O2), P(CO2), pH, and temperature was inserted into Brain tissue, and a small Vein that drained the same tissue was catheterized. Arterial, cerebral venous, and Brain tissue P(O2) and Pco2 were measured during random changes in ventilation to produce five different levels of inspired oxygen (room air, 40%, 60%, 80%, 95%) at each of three different end-tidal Pco2 (20 mm Hg, 40 mm Hg, 60 mm Hg). Arteriovenous shunt was calculated from oxygen and C(O2) content in artery, Vein, and tissue, representing capillary. Tissue P(CO2) was 8 mm Hg greater than Vein Pco2 during hypocapnia and this difference increased to 20 mm Hg during hypercapnia. Vein P(O2) was 8 mm Hg higher than tissue P(O2) during hypocapnia, and this difference increased to 40 mm Hg during hypercapnia. Shunt fraction increased from 10%-20% during hypocapnia to 50%-60% during hypercapnia. These results show that Brain Vein and tissue P(O2) and P(CO2) differ because of arteriovenous shunting and this difference is increased as end-tidal P(CO2) increases. IMPLICATIONS: We found, in dogs, that the gradient between Brain venous and tissue P(O2) and PCO2 is increased with increased arterial P(CO2). The divergence between tissue and venous gases can be described by arterial to venous shunting.
Paul Govaert - One of the best experts on this subject based on the ideXlab platform.
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Brain Vein disorders in newborn infants
Developmental medicine and child neurology, 2014Co-Authors: Marlou M A Raets, Jeroen Dudink, Charles Raybaud, Luca A. Ramenghi, Maarten H. Lequin, Paul GovaertAbstract:The Brain Veins of infants are in a complex phase of remodelling in the perinatal period. Magnetic resonance venography and susceptibility-weighted imaging, together with high-resolution Doppler ultrasound, have provided new tools to aid study of venous developmental anatomy and disease. This review aims to provide a comprehensive background of Vein development and perinatal venous lesions in preterm and term-born infants, and to encourage further research in both the fetus and the newborn infant, with the aim of preventing or mitigating parenchymal injury related to diseases involving Veins.
Guy Edelman - One of the best experts on this subject based on the ideXlab platform.
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Cerebral venous and tissue gases and arteriovenous shunting in the dog.
Anesthesia and analgesia, 1999Co-Authors: Guy Edelman, William E. HoffmanAbstract:UNLABELLED: Cerebral venous blood gas values have been used to indicate Brain tissue oxygenation. However, it is not clear how cerebral tissue and venous measures may vary under physiologic conditions caused by arteriovenous shunt. The purpose of this study was to measure Brain tissue and local cerebral venous oxygen (PO2) and carbon dioxide (P(CO2)) partial pressure during changes in ventilation and to calculate shunt fraction. Eight dogs were anesthetized with isoflurane. After a craniotomy, a Neurotrend probe (Diametrics Inc., St. Paul, MN) that measures P(O2), P(CO2), pH, and temperature was inserted into Brain tissue, and a small Vein that drained the same tissue was catheterized. Arterial, cerebral venous, and Brain tissue P(O2) and Pco2 were measured during random changes in ventilation to produce five different levels of inspired oxygen (room air, 40%, 60%, 80%, 95%) at each of three different end-tidal Pco2 (20 mm Hg, 40 mm Hg, 60 mm Hg). Arteriovenous shunt was calculated from oxygen and C(O2) content in artery, Vein, and tissue, representing capillary. Tissue P(CO2) was 8 mm Hg greater than Vein Pco2 during hypocapnia and this difference increased to 20 mm Hg during hypercapnia. Vein P(O2) was 8 mm Hg higher than tissue P(O2) during hypocapnia, and this difference increased to 40 mm Hg during hypercapnia. Shunt fraction increased from 10%-20% during hypocapnia to 50%-60% during hypercapnia. These results show that Brain Vein and tissue P(O2) and P(CO2) differ because of arteriovenous shunting and this difference is increased as end-tidal P(CO2) increases. IMPLICATIONS: We found, in dogs, that the gradient between Brain venous and tissue P(O2) and PCO2 is increased with increased arterial P(CO2). The divergence between tissue and venous gases can be described by arterial to venous shunting.
Marlou M A Raets - One of the best experts on this subject based on the ideXlab platform.
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Brain Vein disorders in newborn infants
Developmental medicine and child neurology, 2014Co-Authors: Marlou M A Raets, Jeroen Dudink, Charles Raybaud, Luca A. Ramenghi, Maarten H. Lequin, Paul GovaertAbstract:The Brain Veins of infants are in a complex phase of remodelling in the perinatal period. Magnetic resonance venography and susceptibility-weighted imaging, together with high-resolution Doppler ultrasound, have provided new tools to aid study of venous developmental anatomy and disease. This review aims to provide a comprehensive background of Vein development and perinatal venous lesions in preterm and term-born infants, and to encourage further research in both the fetus and the newborn infant, with the aim of preventing or mitigating parenchymal injury related to diseases involving Veins.
Jeroen Dudink - One of the best experts on this subject based on the ideXlab platform.
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Brain Vein disorders in newborn infants
Developmental medicine and child neurology, 2014Co-Authors: Marlou M A Raets, Jeroen Dudink, Charles Raybaud, Luca A. Ramenghi, Maarten H. Lequin, Paul GovaertAbstract:The Brain Veins of infants are in a complex phase of remodelling in the perinatal period. Magnetic resonance venography and susceptibility-weighted imaging, together with high-resolution Doppler ultrasound, have provided new tools to aid study of venous developmental anatomy and disease. This review aims to provide a comprehensive background of Vein development and perinatal venous lesions in preterm and term-born infants, and to encourage further research in both the fetus and the newborn infant, with the aim of preventing or mitigating parenchymal injury related to diseases involving Veins.