Iii. The Fate of Citrate in Erythroblastotic Infants Treated With Exchange Transfusion 12

Abstract

Since the adoption of exchange transfusion as a method in the treatment of newborn infants with severe erythroblastosis (1-3) the question of the possible toxic effects of sodium citrate added to the administered blood, to prevent coagulation, has arisen (4). In this procedure from 85 to 95% of the infant's Rh-positive erythrocytes are replaced by the donor's Rh-negative erythrocytes depending upon the volume of blood that is administered and simultaneously removed (5). In order to effectuate an exchange of 85%o, a quantity of blood equivalent to twice the infant's blood volume must be used, and for an exchange of 98%o, a quantity of blood equivalent to four times the blood volume must be used. Since the average newborn infant has a blood volume in the range of 250-300 ml. the procedure involves the use of approximately 500 ml. and approximately 1,000 ml., respectively. With the use of sodium citrate as an anticoagulant the infant receives as much as 60 to 120 ml. of a 3%o solution of sodium citrate intravenously over a period of about 1½/2 hours.In the experimental animal, the intravenous administration of large quantities of sodium citrate has been shown to produce convulsions (6). This has been ascribed to the formation of a poorly ionized calcium citrate complex which removes calcium ion from the blood stream (7-9). Despite this consideration, exchange transfusions have been successfully carried out in a large number of cases, although occasionally deaths have been reported in the very severely affected cases (10).In order to study the adjustment that the newborn makes to the physiological strains to which it is subjected when an exchange transfusion is 1 The third in a series on the mechanism controlling citric acid levels in the blood. The first two papers in this series appeared in the Journal of Clinical Investigation, Vol. 27, pages 446 and 450, 1948. 2 This paper was presented at the Washington meeting of the American Chemical Society, August 30, 1948. carried out, citric acid, calcium, phosphorus, protein and total base levels were studied before, during and after such a transfusion on a newborn with no symptoms of erythroblastosis and with apparent normal hepatic and kidney function. The newborn studied was a mongolian idiot born in normal delivery. In addition citric acid determinations were carried out on serial bloods withdrawn from eight erythroblastotic infants during exchange transfusion. 500 ml. of blood were freshly drawn from a compatible donor. To this were added 60 ml. of 3%o sodium citrate dehydratee of tri-sodium citrate). This made a total volume of 560 ml. Over a period of approximately 60 minutes 500 ml. of. this citrated blood were infused into the saphenous vein at the ankle. After 60 ml. had been infused the radial artery was cut and the blood was collected in 60 ml. portions, during the progress of the transfusion. The first 60 ml. were added without removal of blood in order to dilate the blood vessels and make the radial artery more apparent. The cells were separated by cen...

Clinical and Biochemical Changes During Exchange Transfusion

“…Hypercitraemia. The possible importance of rising levels of plasma citrate in the production of symptoms during infusion of citrated blood was emphasized by Wexler et al (1949) and Ames et al (1950). The level of citrate was found to rise to a figure 10 to 30 times greater than the pre-transfusion value.…”

Biochemical changes during exchange transfusion in hyperbilirubinemia in term newborn babies

“…However, there was a subsequent fall in the mean post-exchange value (9.31+_1.19 mg%) which was not found to be significantly different (p>0.05) from the mean pre-and mid-exchange values. The initial rise had been observed by earlier workers also (13) and was reported to be due to the administration of calcium gluconate (100 mg for every 100 mt exchanged blood) in order to counteract any fall in serum ionized calcium levels (17,18,19). Such fall occurs d ue to calcium chelating properties of citrate which is present in high concentration in the donor's blood where it is used as an anticoagulant (19,20).…”

“…However, in the present study calcium gluconate was not administered at all (1). Increase in the mean mid-exchange total serum calcium level was possibly due to a rapid rise in serum citrate concentration which has a calcium mobilizing effect on bones (1,3,17). Later the citrate metabolism stepped up and serum levels were stabilized or even fell marginally.…”

The Effect of Oral Administration of Calcium Fructose Diphosphate on the Serum Organic Phosphate, Inorganic Phosphate, Calcium, Protein, and Citric Acid Levels 1

“…However, ashing made no significant difference (2 per cent increase) in the calcium content of the same serum at the peak organic phosphorus level. Increase in citrate levels is probably associated with the rise in calcium levels (15). Protein changes were not considered significant.…”