Gösta Rooth

EARLY REDUCTION OF VASCULAR REACTIVITY IN DIABETIC CHILDREN DETECTED BY TRANSCUTANEOUS OXYGEN ELECTRODE

Reactive hyperaemia in the skin was monitored by transcutaneous measurement of PO2 (tcPO2) (using electrode temperatures of 35 and 37 degrees C) in 13 well controlled diabetic children without clinical signs of vascular disease, and in healthy peers matched for age and sex. The tcPO2 increase was smaller in 12 of the 13 diabetic children than in individual controls. Taking the lower limit of the 95% confidence interval of the increases for the healthy children as a cut-off point, only 4 of the 13 diabetic children had values overlapping into the range of non-diabetics at 37 degrees C. This non-invasive technique, demonstrating a reduced postischaemic response in a group of well controlled diabetic children, may become a useful method for the early detection of diabetic microvascular disorders.

Hydrogen Concentration, Carbon Dioxide Tension and Acid Base Balance in Blood of Human Umbilical Cord and Intervillous Space of Placenta

In a previous paper (Sjostedt, Rooth and Caligara, 1960) we reported on the oxygen tension (PO2) in the blood of the human umbilical cord and the intervillous space of the placenta. It is the purpose of this paper to report on the pH and the carbon dioxide tension (pCO2) in blood from the same sources in order to give a more complete picture of the gas exchange of the foetus and of its acid base balance.

Haemoglobin in cord blood in normal and prolonged pregnancy.

Four hundred and fourteen healthy infants born in the Department of Obstetrics and Gynaecology were investigated. In no case was pregnancy complicated by toxaemia. All infants were delivered spontaneously without complications in occipitoanterior presentation and they showed no signs of asphyxia. In order to obtain reliable information on the duration of gestation, the dates on menstrual age were carefully checked. Only cases with a regular menstrual cycle were included and any in which the duration of pregnancy was in doubt were excluded. Techniques

Oxygen Saturation in the Umbilical Vessels of the Human Fgtus in Normal and Prolonged Pregnancy

The oxygen saturation in the umbilical cord has been studied in 363 cases with special reference to the duration of pregnancy. There was no apparent change in the oxygen saturation with advancing fœtal age and there was definitely no decrease in the mean oxygen saturation in 52 cases where pregnancy was prolonged beyond the 42nd week.The probable physiological values for the oxygen saturation in the fœtal blood from the 36th to the 45th week are 65 to 70 per cent in the umbilical vein and 40 to 45 per cent in the umbilical arteries.

The Oxygen Tension of the Blood in the Umbilical Cord and the Intervillous Space

During recent years there has been a revival of the interest in oxygen saturation in the umbilical blood; this work was started in the 1930s by Haselhorst and Stromberger (1931) and several papers have been published by different groups (Walker and Turnbull, 1953; MacKinney, Ehrlich, Goldberg and Cantwell, 1955; Rooth and Sjostedt, 1955, 1957; Bancroft-Livingston and Neill, 1957; Tumbull and Baird, 1957). It should be remembered, however, that measurements of oxygen saturation mainly give an indication of the amount of oxygen present in the blood. For a more complete picture of the oxygenation it is also necessary to know the oxygen tension (PO2) since that is the force by which oxygen is pressed from the vessels into the tissues and because the physiological effect of the oxygen depends solely on its P02* As oxygen in foetal circulation is obtained from maternal blood in the intervillous space of the placenta, a comparison between the levels of P02 in the intervillous space and in the umbilical vessels will indicate the diffusion pressure drop of the oxygen between the maternal and foetal circulation in the placenta.

The Oxygen Tension in the Cord Blood after Normal Delivery

In order to understand the oxygen supply of the fetus, it is necessary to know the oxygen capacity, the oxygen saturation, the oxygen tension, the pH of the fetal blood, and the dissociation curve. The circulation rate in the fetus, which is so far unknown, is also of fundamental importance. Direct measurements of the oxygen tension in the cord blood seem only to have been made by Beer, Bartels, and Raczowski (1955). They used the potentiometric method of Bartels (1951). Their mean values, 22.4 mm. Hg. in the umbilical vein and 9.2 mm. Hg. in the arteries are lower than might be expected from the oxygen saturation analyses made in our series of uncomplicated deliveries (Rooth and S jostedt, 1955, 1957). A wider knowledge of the oxygen tension (PO,) in the cord blood is therefore necessary. This knowledge is also fundamental in understanding the rise in oxygen tension after birth and the subsequent vasomotor reactions in different vascular systems of the newborn infant.

OXYGEN SATURATION IN THE UMBILICAL CORD

Asphyxia is one of the main causes of foetal death and is considered of importance in the development of cerebral palsy and other nervous disorders of childhood. When studying asphyxia it was found necessary to investigate the degree of hypoxia in the foetal blood. For this purpose the oxygen saturation of the hemoglobin in the vein and the arteries of the umbilical cord was measured in cases of spontaneous and forceps deliveries and Caesarean section.

Combined electronic fetal heart rate and fetal movement monitor — a preliminary report

We have tested a new Doppler ultrasound apparatus which registers both fetal movements and fetal heart rate with a single transducer. To evaluate the reliability of the recognition of movements we also observed them simultaneously by real time ultrasound. In 20 patients with normal pregnancies between the 30th and 42nd week of gestation, taking the real time ultrasound as reference the positive predictive value was 0.93 and the sensitivity 0.94. Maternal hiccups or coughing were recorded as fetal movements. Neither gestational age, the amount of amniotic fluid or the position of the placenta influenced the recognition of movement; nor did fetal breathing, maternal breathing, speaking or laughing.

INTERPRETATIVE ASPECTS ON THE ACID‐BASE COMPOSITION AND ITS VARIATION IN FETAL SCALP BLOOD AND MATERNAL BLOOD DURING LABOUR

Different acid‐base parameters determined in human fetal scalp blood during normal labour have been studied. In evaluating changes in fetal blood acid‐base components during labour changes in corresponding components in the maternal blood must be considered. A tentative model of the maternal‐fetal acid‐base interaction under normal conditions is presented.

A Follow-up Study of Dysmature Infants.

were classified according to Cliffords Stages 0 to 3 (Sjostedt et al., 1958), differed from normal newborn infants in a number of parameters studied. Thus, in the cord blood, the mean oxygen saturation was lower in dysmature infants than in the controls, whereas haemoglobin concentration, plasma pentoses, protein-bound hexoses, bilirubin and nonprotein nitrogen was higher in the dysmature than