Blood flow to fetal organs as a function of arterial oxygen content.

In a sheep preparation the blood flow to fetal organs was studied 3 to 10 days after surgery by means of the microsphere technique over a range of fetal arterial O2 content from 6 to 1 mM. Blood flows to neural tissues (cerebrum, cerebellum, brain stem), heart, and the adrenals increased in inverse relation to arterial O2 content. As a result the arterial supply of O2 to these organs tended to remain constant over the O2 range studied. Blood flow to the fetal lungs decreased progressively with hypoxia. The blood flow to kidneys, digestive tract, pancreas, and carcass had a tendency to remain constant or increase gradually in the transition from high to moderately low levels of arterial O2 content and then to decrease abruptly in more severe hypoxia. Umbilical blood flow did not change systematically in relation to arterial O2 content.

[1]  E. Makowski,et al.  Cerebral blood flow, oxygen consumption, and glucose utilization of fetal lambs in utero. , 1972, American journal of obstetrics and gynecology.

[2]  W. Droegemueller,et al.  Measurement of Umbilical Arterial Blood Flow to the Sheep Placenta and Fetus in Utero: DISTRIBUTION TO COTYLEDONS AND THE INTERCOTYLEDONARY CHORION , 1968 .

[3]  M. D. Jones,et al.  Placental production and foetal utilisation of lactate and pyruvate , 1975, Nature.

[4]  G. Dawes,et al.  Hypoxaemia and aortic chemoreceptor function in foetal lambs , 1969, The Journal of physiology.

[5]  E. Makowski,et al.  Postnatal changes in oxygen affinity of sheep red cells: a dual role of diphosphoglyceric acid. , 1970, The American journal of physiology.

[6]  G. Dawes,et al.  Oxygen lack and autonomic nervous control of the foetal circulation in the lamb , 1956, The Journal of physiology.

[7]  H. Scheffé.  The Analysis of Variance , 1960 .

[8]  I. Silver,et al.  Factors responsible for the stimulation of the adrenal medulla during asphyxia in the foetal lamb , 1965, Journal of Physiology.

[9]  A. C. Guyton,et al.  Oxygen lack as a possible cause of reactive hyperemia. , 1959, The American journal of physiology.

[10]  M. Heymann,et al.  Cardiovascular responses to hypoxemia and acidemia in fetal lambs. , 1974, American journal of obstetrics and gynecology.

[11]  R. Behrman,et al.  Distribution of the circulation in the normal and asphyxiated fetal primate. , 1970, American journal of obstetrics and gynecology.

[12]  M. Purves,et al.  Observations on the Control of Cerebral Blood Flow in the Sheep Fetus and Newborn Lamb , 1969, Circulation research.

[13]  N. Assali,et al.  Effects of Hyperbaric Oxygen on Uteroplacental and Fetal Circulation , 1968, Circulation research.

[14]  C. Brinkman,et al.  Effects of maternal hypoxia on fetal cardiovascular hemodynamics. , 1970, American journal of obstetrics and gynecology.

[15]  L. Peeters,et al.  Regulation of cerebral blood flow in the ovine fetus. , 1978, The American journal of physiology.

[16]  G. Dawes,et al.  Vasomotor responses in the hind limbs of foetal and new‐born lambs to asphyxia and aortic chemoreceptor stimulation , 1968, The Journal of physiology.

[17]  K. W. Cross,et al.  Foetal and Neonatal Physiology , 1973 .

[18]  L. Peeters,et al.  Fetal cerebral oxygen consumption at different levels of oxygenation. , 1977, Journal of applied physiology: respiratory, environmental and exercise physiology.

[19]  B. B. Ross,et al.  The vascular resistance of the foetal and newly ventilated lung of the lamb , 1964, The Journal of physiology.

[20]  N. Assali,et al.  Hemodynamic Changes in Fetal Lamb in Utero in Response to Asphyxia, Hypoxia, and Hypercapnia , 1962, Circulation research.

[21]  A. Hill,et al.  The possible effects of the aggregation of the molecules of haemoglobin on its dissociation curves , 1910 .

[22]  T. Olsson,et al.  Cerebral Reactions during Intrauterine Asphyxia in the Sheep. I. Circulation and Oxygen Consumption in the Fetal Brain , 1974, Pediatric Research.

[23]  E. Makowski,et al.  Fetal oxygen consumption, carbon dioxide production, and glucose uptake in a chronic sheep preparation. , 1972, Pediatrics.

[24]  C. Jones,et al.  The development of some metabolic responses to hypoxia in the foetal sheep. , 1977, The Journal of physiology.

[25]  C. Rosenfeld,et al.  Effect of Estradiol-17, β on the Magnitude and Distribution of Uterine Blood Flow in Nonpregnant, Oophorectomized Ewes , 1973, Pediatric Research.

[26]  O. S. Andersen.  Blood acid-base alignment nomogram. Scales for pH, pCO2 base excess of whole blood of different hemoglobin concentrations, plasma bicarbonate, and plasma total-CO2. , 1963, Scandinavian journal of clinical and laboratory investigation.

[27]  A. Fishman,et al.  Regional Redistribution of Blood Flow in the Mature Fetal Lamb , 1967, Circulation research.