Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from

CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION

BY JAMES W. FARQUHAR and HYLTON SMITH From the Department of Child Life and Health, Univer-sity of Edinburgh, and the Edinburgh Central Hospital Group Biochemical Laboratory (RECEIVED FOR PUBLICATION AUGUST 26, 1957) The development of exchange transfusion has Plan of Investigation greatly altered the prognosis of haemolytic disease In the belief that analysis of serum taken during of the newborn and the procedure is now accepted exchange transfusion would reflect the ability of the as being essential in cases of any severity. It is newborn infant suffering from erythroblastosis carried out wherever the criteria for operation are foetalis to maintain a normal serum electrolyte fulfilled and by operators of varying skill and picture, electrolyte balance with reference to calcium experience. The difficulties associated with blood and potassium ions has been evaluated. transfusion have received increasing attention in recent years, and its employment is beset with Methods problems not only of cytology and serology but of Clinical. The technique of exchange transfusion was microbiology, biochemistry, allergy, dynamics, essentially that described by Farquhar and Lewis (1949). religion and race. Some of these are greatly A careful clinical record was kept during the transfusion. increased by the volume of blood used in exchange This included recording the volume of blood exchanged, copyright. transfusion. Considering that the infant may be heart rate, and the occurrence of clinical incident. The perfused with stored blood of altered chemistry in exchange was carried out slowly, and if the patient was quantities of up to three times his own blood not tolerating the procedure the apparatus was flushed volume, it is surprising perhaps that it can be done with saline and the infant rested for 5-15 minutes. As at all. Hazards such as sepsis, air embolism, many as three or four rest periods were necessary for readjustment in some of the more seriously disturbed portal-vein thrombosis and perforation of the babies. umbilical vein have been described, but are fortu- Specimens of blood were collected at regular intervals http://adc.bmj.com/ nately uncommon. Circulatory overloading is an during transfusion. In the first series of cases studied ever-present danger in the profoundly anaemic blood was collected at intervals immediately before the infant, and it may be precipitated by conducting the administration of calcium gluconate. In the second exchange transfusion too rapidly. Deterioration series blood was collected at intervals immediately before and even death, however, may occur in infants and after the administration of calcium gluconate. In whose pre-operative condition gave rise to no con- the event of any abnormal incident occurring during cern. Such clinical deterioration was observed in transfusion, specimens of blood were collected immedi- 40 % of the cases transfused by Walker and Neligan ately. During specimen collection, contamination of on September 29, 2021 by guest. Protected blood samples with the contents of the polythene catheter (1955), and it did not appear to be related in any was avoided by the following procedure. A few milli- simple way to the baby's initial condition, to birth litres of the infant's blood was sucked into the syringe weight, to the technical difficulties encountered or and rejected into the waste bucket. By this means any to the rate of exchange. Moreover, Walker (1955) residual donor blood was removed from the polythene was led to believe, from inquiries received by him, catheter. The actual blood specimen was then withdrawn that unexpected death was commoner over the and placed in a centrifuge tube. Specimens were centri- United Kingdom than he had previously thought. fuged soon after clot retraction, and the sera were stored Signs of clinical disturbance which had been in the refrigerator until analysis. one observed by of us (J. W. F.) during exchange Analytical. Sodium and potassium were determined transfusions at the Simpson Memorial Maternity by means of the flame photometer; protein by the Pavilion, Edinburgh, between 1948 and 1953, micro-Kjeldahl procedure (King, 1951); total calcium by prompted us to undertake a joint study of a series the method of Sobel and Sobel (1939), with the modifica- of infants during operation. tion that the serum was ashed prior to oxalate precipita- 142 Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 143 tion in order to eliminate citrate; citric acid by a method the pallor of the upper half. Increased venous devised by one of us (H. S.), the principle depending on filling became apparent over the trunk and the veins the oxidation of citrate to acetone with vanadate, and the were noted to drain superiorly. No pitting oedema subsequent distillation of the liberated acetone into an alkaline solution of salicylaldehyde, forming a coloured of the legs was noted. The symptoms disappeared complex which was measured colorimetrically. spontaneously in about half an hour. This Simultaneous electrocardiography would have been of phenomenon has been designated 'distal cyanosis'. much value, but unfortunately no suitable machine was available. Retching. Three infants (B, H and J) suffered from repeated retching of mucus. This is a common Patterns of Clinical Disturbance Observed observation during exchange transfusion, and A quite unexpected near-fatality observed during because of this milder degrees have not been exchange transfusion in 1953 finally provoked these recorded. observations. A mature female infant of 8 lb. 6 oz. birth weight, Shock. Three infants (B, F and M) presented second of a family, had a cord haemoglobin of 17-4 g. a clinical picture to which the term 'shock' has been per 100 ml., a cord serum bilirubin of 3 mg. per 100 ml., loosely applied. These infants showed some or all and a strongly positive Coombs test. There was no of the following features in varying degree. After splenomegaly and the liver was judged to be normal. crying lustily initially on restraint, they became Influenced only by the bilirubin level, it was decided to unduly quiet and pale during operation. At least carry out an exchange transfusion. No trouble was one infant was so pale that the possibility of internal anticipated. Aliquots of 10 ml. of blood were exchanged bleeding was considered. The babies were cool and at an average time interval of one minute. Calcium their abdomens became distended. The latter was gluconate 0 1 g. was injected at intervals of 100 ml. The operation proceeded smoothly until 430 ml. had been not due to liver enlargement. They became exchanged, when the infant suddenly collapsed and 'hypotonic' and unresponsive. Little change in became pale and unresponsive. The heart rate increased heart rate was observed and there was no increase from 132 to 152 beats per minute. Calcium was given in venous pressure. Case B showed this clinical without effect. Glucose 20% solution was given intra- picture within the first 100 ml. of blood exchanged, copyright. venously quite empirically in a dosage of 6 ml. The but survived an exchange of 600 ml. baby appeared to improve, but on resumption of the exchange she collapsed again. Glucose was given once Cardiac Failure. Signs of heart failure more with less convincing effect. The transfusion was congestive then continued much more cautiously and in negative appeared in one case only (J). This baby suffered balance to a total of 740 ml. from repeated retching during the exchange of the first 200 ml. of blood. He remained irritable, and

Of the 19 infants studied, one died during trans- after an exchange of 700 ml. he was beginning to http://adc.bmj.com/ fusion. Six others showed some clinically recogniz- show evidence of deterioration. Respiration able disturbance at some stage of the procedure. became a little distressed and dyspnoea was obvious The remaining 12 infants were normal throughout. after 800 ml. of blood. At this stage the heart rate Different patterns of clinical disturbance were had increased from a resting rate of 138 to one of observed, and a description of these is essential to 164 per minute. The venous pressure in the portal the further understanding of the investigation. circulation rose from a resting level of 7-5 cm. to 30 cm. The baby was a little cyanosed, the super- Distal Cyanosis. Two babies produced an alarm- ficial veins became more obvious and the liver on September 29, 2021 by guest. Protected ing clinical picture which, probably as a result of enlarged. Unfortunately the blood specimen taken modification in technique, was not observed in at this point was lost, but the values found in the subsequent transfusions. In both cases (F and R) preceding one were coexistent with the signs of difficulty was experienced in withdrawing blood early cardiac failure. during the first 100 ml. of blood exchanged. Per- sistent efforts were made to overcome this by partial Acute Non-fatal Collapse. One infant (R) withdrawal and reintroduction of the catheter. In collapsed suddenly and unexpectedly, but he both cases the catheter tip was advanced along the fortunately recovered. He had been well until umbilical vein for about 11 cm. and repeatedly 470 ml. of blood had been exchanged. He then encountered some resistance, which was thought retched and became apnoeic and deeply cyanosed. at the time to be within the portal circulation. Both The heart sounds were faint and the rhythm was babies developed a deep cyanosis of the lower half irregular, but his condition gradually improved of the body, and this contrasted dramatically with over a ten-minute period. This has been broadly Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 144 ARCHIVES OF DISEASE IN CHILDHOOD termed 'acute non-fatal collapse'. Samples of this treated in another hospital. Attempts to employ infant's blood were being taken only at intervals the umbilical vein were unsuccessful and the registrar of 200 ml., and the nearest specimen to the incident catheterized the long saphenous vein in the groin. was taken after 400 ml. of blood had been exchanged. Even here withdrawal was exceedingly difficult, and because the infant was only mildly affected the Death. One infant (1) died during operation. procedure was abandoned. In all cases the speed of This infant was born with assistance by the breech, exchange was fairly leisurely by intention, but in was limp at birth and was covered with yellow some it was prolonged by the technical difficulties vernix. The cord haemoglobin was 9 8 g. per encountered. The numbers are, of course, very 100 ml. and the serum bilirubin 3-5 mg. per 100 ml; small, but there is a reasonable distribution of there were very many nucleated red cells in a peri- severity. Five cases were mild, seven moderate and pheral blood smear and the Coombs test was seven severe. If those cases which pursued a normal strongly positive. Both liver and spleen were course are considered, four were mildly affected, palpably enlarged. Apart from pallor no abnor- three were of moderate severity and as many as five mality was noted until the infant collapsed and died severe. Of the clinically abnormal cases, one was at 500 ml. Necropsy revealed considerable bilateral mildly affected, four were of moderate severity and tearing of the tentorium cerebelli, and a subtentorial only two severe. Of those showing the 'shock' subdural haematoma of such size that the medulla picture, none had severe haemolytic disease. The oblongata was flattened antero-posteriorly. Con- only death occurred in the severely affected group. siderable intraperitoneal haemorrhage was also Only one other of this group (total seven cases) noted. No source of bleeding was found to explain showed any abnormality, and this was limited to this other than some haemorrhage around the retching. umbilical vein in the region ofthe anterior abdominal Regarding the speed of exchange, a total of wall. Although no perforation was found, this 6-36 litres of blood was exchanged in the normal seemed to be the likely source of intraperitoneal group in 1,386 minutes (excluding Cases K and P). blood loss. The pathological opinion was that the The average rate of exchange was 4- 6 ml. per minute, subdural bleeding alone, or with the intraperitoneal

In the abnormal group a total of 4 12 litres of blood copyright. haemorrhage, provided adequate reason for the was exchanged in 968 minutes, so that the average baby's death. speed of exchange was 4 3 ml. per minute. In the cases showing no clinical disturbance, therefore, Relationship of Behaviour to Severity of Disease, the exchange was effected a shade more quickly Birth Weight, Volume and Speed of Exchange on the average, but the fact that in the abnormal The severity of the haemolytic disease process group intentional delays followed the occurrence of mild incidents, and so increased the duration of operation was classified arbitrarily into three grades: (+), http://adc.bmj.com/ moderate (+ +) and severe (+ + +) (Tables I a little, must be kept in mind. and 2). In all cases a Coombs test was positive. The mild cases had a cord haemoglobin value greater Pattern of Serum Electrolytes than 14 g. per 100 ml. and a serum bilirubin of Introductory Remarks. Analytical data referring 3 mg. per 100 ml. or less. Neither liver nor spleen to the cases investigated are charted in Figs. I was enlarged. The moderately severe cases had a and 2. Fig. I shows the individual results obtained cord haemoglobin value greater than 11 2 g. but from six normal transfusions, while Fig. 2 shows less than 14 g. per 100 ml. and the serum bilirubin the individual results from seven transfusions at on September 29, 2021 by guest. Protected was 3 mg. per 100 ml. or less. Some enlargement which clinical abnormalities were observed. From of liver and/or spleen was noted. The severe cases reference to the appropriate figures it will be apparent had a cord haemoglobin value of less than 11 2 g. that they depict only the general trend of serum and a serum bilirubin of more than 3 mg. per 100 ml., electrolytes during transfusion. It will be appre- enlargement of liver and spleen, possibly bruising ciated that, since specimens were collected at or oedema, and in one case a birth weight of less intervals during transfusion, it is only at these points than 5- lb. that electrolytes could be assessed. Fluctuation must The aim of the operation was to employ 80-120 ml. have occurred in the periods between collection of of donor blood per lb. body weight, to use the specimens, this fluctuation being influenced by umbilical route wherever possible and to effect the movement of electrolytes in and out of the plasma exchange fairly slowly. compartment and, of course, by metabolic factors. There were cases where only a small volume was Nevertheless, if this point be borne in mind in the exchanged-for example, Case P. This infant was evaluation ofthe results, it is believed that the general Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 145 pattern which emerges from this investigation of high citrate levels, of calcium-ion depression by adequately portrays the effect of infusion of citrated citrate, of high serum potassium levels and the blood upon serum electrolytes. mutually reinforcing influences of a high potassium and a low calcium ion upon the heart. Calcium Gluconate 30 - 30 20 240.- Icc Icc Ic. Icc Icc Icc Icc 240- 2cc2c2ccC2lcc.4e4cc 2cc2cc2ccic These are depicted in 220- 220- ** * * * Figs. 3 and 4. In each 50- CASE A 50 CASE C 25- every relevant i40- 200- SEVERITY H.0 + 200- SEVERITY HO.D. graphph rlvn DURATION 40 180- 129 0 180- DURATION 162' analytical result in 2 30-I the series is included 20- 160- 20 MD0- 20- E20- a 140- 140 a--~ ,, ,3andmarked by E 10- E 2 120- 120- symbol which denotes 0- -1 - the clinical state of E 100- oo- 0-C> 10 - E 80- _= the patient at the - 80- time when the sample O- 60- 60 - , taken. In Fig. 3 - 5- 40- ,'.wasthe coexisting citrate 20- and calcium-ion levels

05 0 0 Calcium Gluconate Calehm Ghuconats are entered against 30 240- 2cc Icc Icc Icc Icc Icc 301 240- icc Icc Ice each other. If high 220 - so - CASE D CASE E citrate levels per se 40 25- 200- SEVERiTY H.D. 44 sol 200- SLVERITY H. - I 150 were responsible for 180- 0DURATION 128 E 20- 330- 180- clinical abnormality, 20- 160- 'a. 160- then the symbols 20-2 O- u--3- 0 20 140 20 - 20- 10- e c E 140- ---cs 0, ;ts denoting abnormal 0-°15-_-120- 10-C 120 behaviour should be lo.lo0 EEC)S = 100- 0- 100- across the top of the copyright. O-- 80- 80- graph. If clinical 60 60 - 60- abnormality were the 40- 40- result of high citrate 20 20 , " levels depressing cal- 0 0 OJ 0 cium Calcium Gluconate Calcium Ghlcooate ion, however, 30- 240- icc Icc Icc Icc Icc Icc Icc 30- 240- -cc lcc then the abnormal L 220- 220- SEERCASE cases should be at 50- CASE G SEVERITY H.D. + 50- SEVERITY H.D * 25- 200- DURATION 156' 200- DURATION 115' the top of the graph http://adc.bmj.com/ 7240 -40 D-o- O---E--0° ---m__ -a--- 30- 180-I 180- , (Total esehmaqa 6 i and towards the left. 1(160 The of E20- 20- 20- 160- ' upper part the E 14 140- --a graph does not in D

EE10- aZ. 120-I; 0- 120- fact contain the a 100-H Q-I loo- abnormal cases, nor IO- - 80I 80- do they lie pre- i

60- 60- dominantly to the left on September 29, 2021 by guest. Protected

40-A 5 40- of the picture. The 20; 20- one death does lie in 0 0- 05 the top left-hand 0 100 200 0 4005 0 60 070 0 620 '0O 40 500 600700 corner, but otherwise VOL. BLOOD EXCHANGED VOL. BLO8 EXCHANGED there is reasonable

o---o K o Cit A---A Ca++ V v Total Ca dispersal of the FIG. 1.-Serial serum electrolyte levels during six norn mal exchange transfusions. abnormal symbols among those which imply normal be- The Group as a Whole. From the outset of the haviour when the specimen was taken. In Fig. 4 investigation attention was focused on the relation- the serum potassium levels were plotted against the ship of four biochemical situations to the clinical coexisting levels of calcium ion. If hyperpotas- behaviour of the baby. These were: the influence saemia were responsible, then the abnormal cases Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 146 ARCHIVES OF DISEASE IN CHILDHOOD should lie across the top of the picture, whereas if abnormal cases should lie in the top left-hand depression of calcium ion were responsible, then quadrant. Apart from the important exception that they should lie to the left of the picture. If the the only death did in fact represent the highest serum offending biochemical upset were coexisting hyper- potassium level at the lowest calcium-ion level, the potassaemia and calcium-ion depression, then the other abnormal symbols are scattered across the

CASE B 30 CASE F CASE H c cc Calcium Glucenctc 0 50 240 Calcium Gluconate 2240° 220240- 05051 50- 220 * * _ 50- 50- E 25 200- 25- 25- 200 + o 40- g40- I 40 180- 40- 180 O - 30- 'Z30- Z-30- 20 160 , b W 20 20- - 160 a--a.a E 20- E 20- E E 20-W. E :140- c -2 0140 a 0- 10-10 120- -E IS- 120 0- _ 0°1- E E 100 a E I00- 80 0 0- ,! 10. 80 60- SEVERITY HD 4+- 60 SEVERITY HHD -N* DURATION 110' DURATION 1 195' 5- 40- 5- 40

20- 20 - " .

10 0 0 0 I. . r---r---i 0 100 200 300 400 300 600 700 100 200 300 400 500 600 700 0 100 200 300 400 500 600700 Calcium Gluconate cc Calcium Gluconate cc Calcium Gluconate probobly Icc at each 100 ml I I CASE I CASE J hII I U I CASE M I I1I1I I1I1 30] 301 307

50- - 50- E 25'II E 25 25 040. 10 o40-

3l0- 30- copyright. E 20' E 20- 20 20- - S 20- E E 20-50ID- U 0- - 205 10lo 0c 10-0 0-15W. 0-15 -°E 5. E E 0 10 105 3 10- http://adc.bmj.com/

o0 0 0 0 100 200 300 400 500 600 700 0 100 200 300 400 500 600 700 VOL BLOOD EXCHANGED VOL BLOOD EXCHANGED VOL. BLOOD EXCHANGED cc Calcium Gluconate CASE R 0.5 05 301 240 )-+ I a o--0 K 220 50- O C it 20C on September 29, 2021 by guest. Protected 40- )ao SEVERITY HD -* 4--A Ca++ 180 DURATION 90 0- )- Y-v Tat Ca 20 16C , 20- E a SHOCK ,, 140 O RETCHING I - 12C 0- a DISTAL CYANOSIS 10C i DEATH 10 = 80 X ACUTE NON-FATAL COLLAPSE 60 * CARDIAC FAILURE 40 )- 20 "-A -, 0 1. .- 0 100 200 500 400 500 600 700 VOL. BLOOD EXCHANGED FIG. 2.-Serial serum electrolyte levels during seven abnormal exchange transfusions. Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 147 picture and fairly evenly disposed among the normal and if, in fact, the formation of calcium citrate cases. From these two pictures it is possible to in vivo were dependent only upon chemical kinetic state that, with the exception of the fatal case, there factors, then all available calcium ion in the plasma was no relationship in this series of cases between of these infants, except for the small amount liberated the coexisting biochemical values and the clinical in the primary dissociation, should have been behaviour at the moment of taking the specimen. combined as calcium citrate. That this situation It was apparent that a pattern of serum electro- did not exist was apparent from the clinical state of lytes during transfusion emerged from this investiga- the infants. The physiological environment, then, tion, this pattern being common to all infants must be more complex than experiments in vitro whether or not clinical incident was observed. In would suggest, although all the calcium supplied in summary, there appeared to be an increase in total the form of calcium gluconate appeared to be calcium and citrate, a decrease in active calcium ion, inactivated immediately after injection (Fig. 5), if it and either no change or an increase in serum can be presumed that calcium gluconate is com- potassium. Several conclusions have been drawn pletely ionized. The results are illustrated in from these results. Fig. 5. The absence of the classical manifestations of hypocalcaemia during transfusion even though Citrate and Calcium. Great excess of citrate was subsequent analysis of serum showed a profound found in the serum during exchange transfusion, depression of calcium-ion concentration, is difficult

o 346 + 319 o 26? * 255 o 240 0 0 225 0 0 0 203 50* 200- 0 0 0

0 45.

!80- copyright. 0 8 0 40 0 160- 0 °o ct) o 0 000 0 0 + 0 0 0 0 35- 140- 000 0 E 0 00 30- O00 0 http://adc.bmj.com/ o 120- 00 , 000 , 0o00 0 000 0 7 cbo 8 E E cl225- 0 9 1- 00-100- 4a %o \ (9 0 E 0 0 0 v 20 ° 80 0 9 00 0 so0 0 8 Oc 0 IP0 on September 29, 2021 by guest. Protected 0 &0 o00 15 0 60 0 0 . 0 o 0 0 0 o cI0 0 0~~ 0 I0 40. 00 oo0 a0 \00 o ox o 5. 20 0 o8 0 \ O. 20\ III A I D- 9 I v I IFs I- 2 3 4 I 1 2 3 4 5 Ca ion mq /lOOml Ca ion. mq / 100 mI FIG. 3 -Clinical behaviour during exchange transfusion related to FIG. 4.-Clinical behaviour during exchange transfusion related to plasma values of citrate and calcium ion. plasma values of potassium and calcium ion. Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 148 ARCHIVES OF DISEASE IN CHILDHOOD to explain. Since the formation of calcium citrate the absence of active metabolic factors the reaction is known to be a slow reaction, it is suggested that between citrate and calcium ions was able to reach completion.

SEVERITY ND * SEVERITY N D 11+ It is claimed that during exchange transfusion DURATION 115' DURATION 114' the rate of transfusion is the most important -6E0- E 6-0- factor in the development of hypercitraemia. o ~o cc Icc Ilcc lcc O cec lcc Table I shows the infusion rate of citrate in this

E series, and it is apparent that the safety rate recommended by Mollison (1951) was com- ,, 2 -0 - ' [ monly exceeded. There did not appear to be any correlation between the hypercitraemia and the citrate infusion rate, and it is considered 0 200 400 600 0 200 400 600 VOL BLOODEXCNANGED VOL BLOOD EXCHANGED significant that hypercitraemia of equal severity SEVERITY HD -+ developed in both the clinically normal and CASE P DURATION Not recordled abnormal groups. All infants showed consider- 6.0 2cc able ability to 'metabolize' infused citrate, even in IE i the presence of alleged hepatocellular immaturity. 40 It has been postulated that a high serum citrate level in the resting state is indicative of hepato- cellular dysfunction. Hypercitraemia was com- monly observed in the pre-transfusion state in this

200400 investigation. Natelson et al., (1948) quoted the 0 200 400 600 800 2.0 VOL. BLOOD EXCHANGED VOL BLOOD EXCHANGED normal range of serum citrate as I 5 to 6-0 mg. per 100 ml., with a mean value of 3-8 mg. per CASE SEVERITY ND 14- CASE R SEVERITY HD *+1 DURATION 120' ~DURATION 116' 100 ml., and in this series the range was 1P4 to 6.0 Icc I cc cc 6.0- Icc 05cc 40 0 mg. per 100 ml., with a mean value of c~ GLUCONAT

rE 12- 6 mg. per 100 ml. The fatal case had a resting copyright. 0 4 K0 serum citrate level of 40 0 mg. per 100 ml., yet ~~~~~~~~~~~EAFTER rE post-mortem examination revealed no gross E20 L 2O0 GLUCONAT hepatocellular damage. Furthermore, liver enlargement was not a common feature in any .0 200 400 600 0 200 400 of the other cases, but this does not exclude VOL. BLOOD EXCHANGED VOL. BLOOD EXCHANGED the possibility of a 'metabolic' immaturity FIG. 5.-Effect of calcium gluconate on serum calcium-ion concentration,. existing. Confirmatory evidence of high resting citrate values has been provided by the low http://adc.bmj.com/ complex formation may have been incomplete level of resting serum calcium ion observed in this during transfusion, but on storage of the serum in series.

TABLE 1 TABLE RELATING RATE OF TRANSFUSION, RATE OF CITRATE INFUSION AND INCIDENCE OF CLINICAL ABNORMALITY Severity of Birth Volume of Blood Time taken

Case Haemolytic Weight Exchanged for Exchange Citrate Infused Incident on September 29, 2021 by guest. Protected Disease (kg.) (ml.) (minutes) (mg./kg./1hr.) A + 3-2 700 129 286 B + + 2-9 600 107 397 Shock, retching C ++ 3-3 700 162 202 D ++ 3-2 700 128 400 E +++ 2-5 500 150 356 F + 2-6 500 125 - Distal cyanosis G + 3*5 700 156 293 H +++ 2- 3 500 195 242 Retching I + + + 2-7 500 160 218 Death J + + 3-3 850 110 542 Retching, heart failure K + 3*2 300 240 80 - L +++ 3*0 600 150 385 M + + 2*7 700 190 240 Shock N ++ 2-6 500 115 404 0 +++ 3-8 600 114 302 P + _ 200 Not recorded - Q +++ 3-2 560 120 303 R + + 3 6 470 81 298 Distal cyanosis, acute collapse S +++ 3-8 800 162 334 Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 149 Potassium. Variations in serum potassium during point is worthy of note: the plasma potassium exchange transfusion were unpredictable. Hill level of the donor blood used in the fatal case was (1954) quoted the normal range of serum potassium 110 mg. per 100 ml., and at death coexisting high in the newborn infant as 17 5 to 21 1 mg. per potassium and low calcium-ion concentrations were 100 ml. In this series the normal pre-transfusion recorded. Whether the high potassium level influenced the onset of cardiac failure could not be 2 TABLE ascertained, since electrolyte imbalance was not ANALYSIS OF CASES ACCORDING TO SEVERITY OF HAEMOLYTIC DISEASE considered to be the cause of death.

+ ++ +++ Summary of Biochemical Changes in Abnormal Total number of cases 5 7 7 Cases Clinically normal .. 4 3 5 Fig. 2 illustrates serum electrolyte changes during Clinically abnormal 1 4 2 (a) Shocked 1 2 - exchange transfusion in the abnormal cases. (b) Retching .. 2 1 (c) In cardiac failure 1 - (d) Acutely collapsed - _ - Distal Cyanosis. This was not associated with (e) Dead- any particular electrolyte pattern. Symptoms appeared early in the exchange, and at a time when range was 13-3 to 40 0 mg. per 100 ml. Table 3 serum citrate was beginning to rise and serum- shows that five infants (F, G, K, N, R) had pre- calcium ion to fall. Both infants had a pre-trans- transfusion serum potassium levels above normal, fusion hyperpotassaemia, which persisted through- and in these instances either no change or a rise out transfusion. accompanied the transfusion. Of those infants who Retching (Cases B, H, J). This was associated had a normal pre-transfusion serum potassium level, with a hyperpotassaemia, a rising serum citrate level, five (B, D, I, J, L) developed a hyperpotassaemia and a serum calcium ion which was by no means during transfusion. All these infants were transfused unduly low when compared with other apparently with donor blood with a plasma potassium content normal transfusions. of over 30 0 mg. per 100 ml. Except in the fatal copyright. case, however, the hyperpotassaemia was not relat- Shock (Cases B, F, M). In Case B, shock able to any particular clinical abnormality, since the appeared before any marked change in either serum phenomenon was observed in both clinically normal citrate or calcium ion, but hyperpotassaemia was and abnormal infants. Furthermore, two infants present after only 100 ml. of blood had been classified as clinically abnormal (H, M) had a normal exchanged, and therefore coexisted with the appear- serum potassium level throughout transfusion. One ance of clinical signs of shock. Case F presented http://adc.bmj.com/ TABLE 3 CHANGES IN SERUM POTASSIUM DURING EXCHANGE TRANSFUSION Volume of Blood Exchanged (ml.) Case 0 100 200 300 400 500 600 700 Serum Potassium (mg. per 100 ad.)

- A 16-2 20 5 20-8 20 4 22 7 24 0 25-7 on September 29, 2021 by guest. Protected B 17-0 34-0 25 0 20 0 26 5 30 0 30 0 - C 13 3 13 6 19.0 14-3 14-0 14 0 12 7 17 7 D 20 5 20 5 21 4 23-2 38 0 35 4 26 0 24 4 E 16 1 16 1 13 8 17 4 17 5 15 4 _ _ F 23-1 18 8 22-7 20 6 25-1 26 0 - _ G 37 0 37-5 38 0 38-4 38-2 36 2 35 7 37-0 H - 23-0 23 1 22-0 17-8 14 4 - _ I 12 4 14 0 18 0 20-0 28 0 36 0 - _ J - 27-7 31 6 28-3 39 5 38 0 34-8 34-8 K 31-0 36 0 30 0 50-0 - - - - L - 20 0 24 5 23-5 18 0 18 0 - _ M 16-5 15-7 18-2 17-0 16 0 16 5 16-5 17-1 N 28*0 - 28 0 - 29*0 - 33*0 - 0 18-7 - 18-1 - 21 7 _ 22-4 P 17-7 _ 243 - - - - Q 19 9 - 21 8 - 17-8 - 17-3 R 40 8 - 53 2 - 50 1 - - _ S 18 0 - 17 6 - 24 8 - 214 19-0 Mean value 21 6 22-9 24 9 24-3 26 0 25 2 26 7 25-0 Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 150 ARCHIVES OF DISEASE IN CHILDHOOD only a mild hyperpotassaemia. Signs of shock imbalance, since similar biochemical changes were appeared towards the end of the transfusion in common to all the infants of the series. Serum Case M. At this time the serum citrate level had electrolytes reflect the total electrolyte pattern to suddenly increased to 250 mg. per 100 ml., but some degree, but clinical abnormality need not serum potassium was within the normal range. necessarily be the result of a sudden change in Serum calcium-ion level was apparently uninfluenced plasma electrolytes. Rather it may be due to pro- by the sudden change in citrate, remaining, as it had longed exposure of the intracellular environment to done throughout the transfusion, at about 2 mg. a gradually changing extracellular environment. per 100 ml. Considered from this point of view, a study of serum electrolytes throughout a transfusion is more Cardiac Failure (Case J). Heart failure appeared important than the assessment of electrolytes at any at a point in the transfusion when the serum particular instant in a transfusion. Critical evalua- electrolytes were beginning to return towards tion of the results of this investigation has failed to normal. The citrate level had fallen substantially, show a correlation between electrolytic imbalance total calcium had reached a peak of 15 mg. per and clinical abnormality during transfusion, but 100 ml., calcium ion had risen by 1 0mg. per 100 ml., there is no doubt that all infants undergoing exchange and serum potassium had fallen by 5 mg. per transfusion are exposed to an abnormal biochemical 100 ml. to a level of 30 mg. per 100 ml. state over a prolonged period. Acute Non-fatal Collapse (Case R). The infant collapsed after 500 ml. of blood had been exchanged, GENERAL DISCUSSION and the nearest sample of blood to this incident, Citrate taken at 400 ml., indicated a profound hyper- Hypercitraemia. The possible importance of potassaemia although the serum citrate level was rising levels of plasma citrate in the production of falling and the serum calcium ion was relatively symptoms during infusion of citrated blood was stable at 2 mg. per 100 ml. It is significant that the Wexler et al. (1949) and Ames et al. bottle of donor blood had been changed after 400 ml. emphasized by (1950). The level of citrate was found to rise to a copyright. had been transfused, and the plasma potassium than the mg. figure 10 to 30 times greater pre-transfusion concentrations in the two bottles were 85 4 value. This was accompanied by a decrease in and 52 8 mg. per 100 ml. respectively. The plasma plasma calcium-ion concentration. Prolongation of potassium value after the exchange of 400 ml. of the Q-T interval on ECG tracings was recorded by blood, although high, was actually a little lower than the latter could be might Ames et al. (1950). Although it had been earlier, and a further reduction attributed to the depression of calcium-ion concen- have been expected by the time of the clinical by citrate, no constant relationship existed tration http://adc.bmj.com/ incident, in view of the lower plasma potassium between the plasma citrate concentration and the content of the second bottle. ECG change. Furthermore, the Q-T interval could return to normal in the presence of continued high Death (Case 1). In the fatal case, serum citrate made on in the series, levels of citrate. These studies were had reached by far the highest level infants. Plasma total calcium yet death took place when the citrate level was convalescent citrate, concen- and total protein were determined, and plasma beginning to decrease. Serum calcium-ion was assessed indirectly tration was not measurable, nor had it been for calcium-ion concentration by employing the normogram of McLean and on September 29, 2021 by guest. Protected some time before death. At the time of death the babies became a peak value of Hastings (1935). Several of serum potassium had reached irritable during the infusion; their skins were pale 36 mg. per 100 ml. Thus there existed a profound skin was and hyperpotassaemia. and mottled, and a normal temperature hypocalcaemia not restored by the use of blankets alone. One infant collapsed suddenly and responded only to prolonged Hyperpotassaemia. This was the only constant dead feature of the abnormal cases, and it was severe in resuscitative measures. Another was found during transfusion. The authors considered that the cases of cardiac failure, acute non-fatal collapse the and death. Three apparently normal infants these acute disturbances were almost certainly of result of acute lowering of plasma calcium-ion level. (D, G, L), however, exhibited hyperpotassaemia shows similar magnitude. Critical study of the case records, however, no convincing evidence for such a belief and reveals Conclusion. It is believed that none of the the presence of other factors predisposing to com- clinical incidents was due entirely to electrolytic plication. They believed that the absence of reactions Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 151 in the majority of cases might be explained on the stipulates a maximum rate of 260 mg. of citrate basis of the existence of forces capable of counter- per kg. of body weight per hour, but Wexler et al. acting the calcium-ion-lowering effect of citrate. (1949) and Walker et al. (1955) freely admit to However, they provide no explanation of why these exceeding this rate without clinical incident. In the two less fortunate individuals should have been present series similar conditions prevailed. Nakasone deficient in this homoeostatic mechanism. More et al. (1954) performed an interesting experiment in recently Bunker et al. (1955) have shown, in a series which citrate solutions of varying strengths were of 130 adults who received moderate to large infused into dogs and the response of cardiac muscle volumes of citrated blood, that many patients was measured by ECG tracings. They suggested developed hypercitraemia, and theoretically calcium- that it was not the actual level of citrate in the ion concentration in the plasma ought to have been perfusate which was the factor precipitating cardiac seriously depressed. More marked elevation of changes, but rather the cumulative dose of citrate plasma citrate occurred when transfusion was in the animal's body. In other words, hypocalcaemia extremely rapid, prolonged or repeated. Higher was induced after the infusion of a critical amount of levels also occurred where the liver was damaged, citrate, whether this was attained over a short period and this may be important in the newborn infant by the infusion of a solution containing a high with or without haemolytic disease. concentration of citrate or after a longer period with The present investigation has demonstrated conclu- a solution containing less citrate. For this reason sively that a great increase in serum citrate occurs dur- the slower the rate of transfusion the less severe ingthe infusion ofcitrated blood, and itis important to the hypercitraemia which will develop. It is consider the facts which influence this phenomenon. suggested that the clinical incidents in this series The acid-citrate-dextrose mixture used as an anti- were not related to the infusion rate of citrate. coagulant in this country has been criticized and Reference to Table 1 will show that the safety rate praised for many years. When it was first instituted was often exceeded in cases which appeared normal the dangers of citrate were emphasized, but until throughout transfusion, yet in other abnormal cases the technique ofreplacement transfusion and massive the infusion rate was below the recommended safety blood transfusion became common, little attention rate. copyright. was focused upon the possibility of citrate intoxica- tion in medical practice. In the infants in this Metabolism of Citrate. It should be borne in series, amounts of citrate ranging from 738 to mind that reports describing rapid metabolic 3,413 mg. were infused into a plasma compartment breakdown of citrate during the infusion of citrated of less than 200 ml. average volume, so that accumu- blood are based on observations of plasma citrate lation of citrate under these circumstances could be concentration during a period when rapid diffusion dangerous. It is believed that citrate in stored out of the plasma compartment is occurring. http://adc.bmj.com/ donor blood is confined essentially to the plasma. Transfer of citrate to other compartments of body Thus, if the recommended ratio of volume of anti- water would account, at least in part, for the dis- coagulant to blood is strictly adhered to, then the appearance of exogenous citrate out of the plasma plasma citrate content of the donor blood should water. The average amount of citrate contained be about 600 mg. per 100 ml. It will be appreciated in 100 ml. of citrated donor blood is 370 mg. that any marked deviation from the standard Assuming that no transfer occurred out of the technique may result in significant changes in the plasma compartment into interstitial water, then plasma citrate. Ames particularly emphasized this the amount of this citrate which would be retained on September 29, 2021 by guest. Protected point when describing an alleged case of citrate after the exchange of 100 ml. of blood by the intoxication following the infusion of plasma con- technique employed in this investigation would be taining 1,536 mg. of citrate per 100 ml. With this in about 320 mg. In practice, however, a proportion mind Walker and Neligan (1955) recommend the of this would be transferred to interstitial water, use of packed cells in exchange transfusion. and, assuming even distribution throughout the extracellular water, about a seven-fold reduction in Speed of Citrate Infusion. Although the plasma the theoretical maximum plasma concentration citrate level in the donor blood is the first considera- could be expected. The actual level in the plasma tion, the rate at which it is infused is obviously would depend on the degree of transfer of the citrate important. It is desirable that the rate of transfusion at the time of collection of the specimen, but it be adjusted so that the homoeostatic mechanisms should be within the range of 46-320 mg. per 100 ml. controlling citrate are able to deal with the citrate Thus the levels recorded in this series indicate that as fast as it is being infused. Mollison (1956) a considerable portion of infused citrate migrated Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 152 ARCHIVES OF DISEASE IN CHILDHOOD out of the plasma compartment after each 100 ml. of two infants (I, M) were able to metabolize infused blood exchanged. Increased intracellular meta- citrate very efficiently. If citrate intoxication were bolism of citrate was likely to occur under the the causative factor in some or all of the clinical stimulus of the infusion of citrate. The exact rate incidents in this series, then it is difficult to explain of oxidation of citrate in the human being is un- the fact that serum citrate levels of a similar magni- known, but toxic effects appear to depend on dosage tude did not precipitate incidents in the normal and rate of administration. Most tissues contain infants. a specified citric-acid dehydrogenase, the liver and renal parenchyma being the most active sites of Citrate-induced Hypocalcaemia. The high serum metabolism (Thunberg, 1953; Mfartensson, 1940). citrate recorded in this investigation should have Wexler observed delayed removal of citrate from induced severe hypocalcaemia. The theoretical plasma in one fatal case which showed gross liver implications are that all available calcium ions in damage at necropsy, and from this evidence he the plasma of infants undergoing transfusion should postulated that delayed citrate metabolism might be inactivated, but the results indicate that, although result from impaired liver function. In the fatal significantly reduced, this reduction was not com- case of the present series a similar delayed removal plete except in the fatal case. Two explanations are of citrate was observed, yet post-mortem examina- proposed. First, citrate was present in the plasma tion revealed no severe liver damage. It is quite in high concentration, but there was no evidence possible that a mild degree of metabolic immaturity to show whether the whole or part of it was present exists in newborn infants, especially those suffering in an active ionic form. In fact an inactive molecule, from erythroblastosis foetalis. This would explain possibly bound to protein, may have existed. Such the resting hypercitraemia observed in some cases complexes are known to exist in the case of protein in this series. It can only be concluded, however, and glucose and the lipoproteins. Under such that all infants appeared to have efficient homoeo- circumstances only ionized citrate would be available static mechanisms for removing infused citrate for reaction with calcium and other cations. from plasma. Secondly, the formation of calcium citrate is not an

It is suggested as a hypothesis that all the factors instantaneous reaction, and this might explain the copyright. discussed must operate during the infusion of apparent discrepancy between the absence of clinical citrated blood. Initially the prevention of severe manifestations of tetany, even though subsequent hypercitraemia by careful adjustment of the donor analysis of serum showed a profound depression of plasma citrate level and the rate of transfusion can calcium ion. During transfusion calcium citrate be controlled by the operator. Presumably any formation may have been incomplete, whereas on infused citrate enters the plasma, and from there it storage of the serum in the absence ofenzyme action,

is transferred to interstitial water and finally to the reaction was allowed to reach completion in the http://adc.bmj.com/ intracellular water, where it is metabolized. Refer- presence of excess of citrate ion. Whatever the ence to Figs. 1 and 2 will indicate the general pattern explanation, analysis revealed that complete in- of serum citrate during transfusion. The initial activation of calcium ion in serum did not occur. dramatic rise to a level between 100 and 160 mg. There was no evidence to confirm the finding of per 100 ml. may represent a phase in which citrate others (Lansing and Scott, 1942) that significant is essentially confined to the plasma. Once mobilization of calcium ion occurred from intracel- mechanisms controlling transfer out of the plasma lular sources, nor did it appear that the injection of compartment become operative it is reasonable to calcium gluconate was effective in elevating calcium on September 29, 2021 by guest. Protected expect a fall in the plasma citrate if the rate of ion in serum. On clinical grounds, Walker and transfer exceeds the rate of citrate infusion in the Neligan (1955) abandoned the use of gluconate, and plasma. This has been confirmed in the present they did not observe tetany in a series of 272 trans- investigation. Fluctuations observed at later stages fusions. in the transfusion may reflect the efficiency of Herlitz (1942) observed active tetany in infants intracellular metabolic pathways. Thus a rising whose plasma calcium-ion level had fallen below citrate in the presence of a constant rate of citrate 3 5 mg. per 100 ml., yet even with serum calcium-ion infusion suggests some impairment of function levels below 2-0 mg. per 100 ml., classical tetany (Cases I, M). Conversely, a falling serum citrate was not seen during this investigation. The absence level suggests efficient metabolism, while a fluctuat- of clinical abnormality is not inconsistent with a ing citrate level may be indicative of sudden changes reduction in calcium ion, as the factors governing in the citrate intake with which the intracellular neuromuscular irritability are complex, and the metabolic processes are unable to cope. All except maintenance of a normal state of irritability may Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 153 have been due to compensatory mechanisms. The about twice the infant's blood volume. The influence exact means by which tetany is brought about has of transfusion upon serum potassium concentration not yet been elucidated, but the original work of in eight infants was studied by Miller et al. (1954). Ringer and Loeb (discussed in any standard textbook Hyperpotassaemia was present, particularly when of physiology) might elucidate the problem. They the donor blood had been stored for a week or postulated a delicate equilibrium between the longer. No convincing proof was offered that the cations of the serum, and any disturbance of this high potassium levels were harmful to these infants. equilibrium, such as a decrease in calcium, mag- Sudden unexplained death in two infants also nesium or hydrogen ions or an increase in sodium, prompted the investigation carried out by Campbell potassium or hydroxyl ions, causes hyperirritability (1955). Hyperpotassaemia was present in three of of the tissues. It has been shown in this series that four deaths in the series, but comparably high figures an increase in potassium and a decrease in calcium were recorded in infants who had shown no ion occurred in serum, thus favouring the develop- abnormality. Although the levels were potentially ment of neuromuscular hyperirritability. lethal, Campbell was unable to ascribe the deaths It has been demonstrated that citrated blood is with certainty to hyperpotassaemia. Some success weakly acid in reaction, and the infusion of such a was obtained with insulin in maintaining more medium would favour the production of a metabolic normal potassium levels, and the author's experience acidosis. This problem is at present under investiga- of comparative morbidity and mortality in compar- tion by Walker (personal communication, 1956), but able control and test groups is awaited with interest. no results have been reported to date. Increase in Serum potassium levels recorded in the present hydrogen-ion concentration would tend to compen- investigation indicated that 60 % ofinfants developed sate for thecoexisting hypocalcaemia and hyperpotas- a hyperpotassaemia either before or during trans- saemia in terms of neuromuscular irritability. For fusion, but these changes were common, even in the example, MudgeandVislocky (1949) observed thatthe asymptomatic infants. Rise in plasma potassium acidosis of chronic renal disease was not specifically level during exchange transfusion is influenced by related to a change in acid-base equilibrium, but was the intake of potassium in the donor plasma, the associated with a decrease in intracellular potassium ability of the renal mechanism to excrete excess copyright. and a rise in intracellular sodium. In this investiga- potassium and the efficiency of intracellular tion perfusion of donor blood did not significantly 'metabolic' sites in removing potassium from the alter the infants' sodium level in the face of a virtual plasma. It was apparent in this investigation that replacement of their blood and a donor plasma the development of hyperpotassaemia was closely concentration around 400 mg. per 100 ml. Since related to the infusion of donor blood. The inci- renal excretion of sodium must have been negligible dence of hyperpotassaemia was high when the donor during transfusion, diffusion or transfer of excess

plasma potassium level exceeded 30 0 mg. per http://adc.bmj.com/ sodium out of the plasma compartment must have 100 ml. As in the case of citrate, however, the high occurred. Is it reasonable to postulate that at least serum potassium levels were not relatable, sur- some of this sodium entered the intracellular water, prisingly, to the rate of transfusion. Thus the possibly reflecting that some movement of potassium development of hyperpotassaemia may be due to into the extracellular water had occurred? accumulation of potassium rather than to the potassium concentration of the perfusate. In the Potassium adult renal excretion of potassium is a most The leakage of potassium from red blood cells important homoeostatic mechanism preventing on September 29, 2021 by guest. Protected during storage is a well-known phenomenon potassium intoxication, but, since renal immaturity (De Gowin et al., 1940), and the significance of this is an accepted phenomenon in the newborn, their was emphasized by Mollison (1951). Toxic levels ability to excrete excess potassium is doubtful. In of potassium in blood plasma are associated with fact the mean normal urine output in the first cardiac arrest, and in fact the injection of potassium 24 hours is about 20 ml., so that the maintenance citrate solution into the coronary circulation has of a normal serum level during transfusion must been used experimentally to produce elective depend upon mechanisms other than renal. One of temporary cardiac arrest (Melrose et al., 1955). In these must be the transfer of potassium from the the adult the transfusion of one or two pints of blood plasma to other compartments of the body water. does not greatly affect the recipient's plasma Simple distribution within the extracellular water potassium concentration, but the situation is will result in a seven-fold decrease in the concentra- different during exchange transfusion in a newborn tion of any exogenous potassium which is confined infant, where one pint of blood is equivalent to initially to the plasma. The serum potassium Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 154 ARCHIVES OF DISEASE IN CHILDHOOD concentration per se does not necessarily reflect the firmed in this investigation. There is some sugges- state of cellular potassium, and it is not justifiable tion that the hyperpotassaemia may have pre- automatically to associate a high serum potassium cipitated heart signs in the cases of acute non-fatal level with a toxic accumulation of potassium in collapse, cardiac failure and death, but completely body water. In fact Tarail and Elkinton (1949) asymptomatic infants presented a hyperpotassaemia have shown that a cellular deficiency of potassium of similar magnitude. The evidence is strong in may exist in the presence of a high serum potassium favour of profound electrolytic imbalance in the level. Although this would explain the absence of fatal case, although the actual cause of death was potassium intoxication in the cases in this investiga- found to be haemorrhage. It appears that there is tion with a high serum potassium level, it is difficult no association between the clinical disturbance to imagine in infants suffering from erythroblastosis observed during exchange transfusion and the foetalis. These infants are exposed to a severe changes which undoubtedly occur in plasma haemolytic process which starts in utero, and it is electrolytes. possible that in the absence of a renal homoeostatic mechanism these infants are in a state of positive Other Possible Explanations of the Clinical potassium balance. This fact tends to be confirmed Disturbances by the high incidence of resting hyperpotassaemia. Circulatory Stress Experiments (Joseph et al., 1939; Fenn, 1939; Interference with Postnatal Readjustment of Houssay et al., 1936; Eichelberger, 1941) have shown Circulation. The picture of differential cyanosis of that the intravenous injection of soluble potassium the distal half of the body is most alarming. Only salts results in the accumulation of potassium two such cases have been seen by J. W. F. and both within the liver cells, and this process is enhanced occurred in this series. In each great difficulty had by the simultaneous infusion of glucose solution. been met in withdrawing blood and much time had Presumably potassium enters the intracellular space been spent manipulating the catheter. On the first of the hepatic cells during hepatic glycogenesis. occasion the development of some venacaval This is suggested as a working hypothesis in the obstruction was considered, and the spontaneous only a temporary present investigation. The liver is resolution of the disturbance was witnessed with copyright. site, but it serves as a means of preventing potassium relief. The production of a temporary veno-arterial intoxication in the absence of renal regulating shunt through a patent ductus arteriosus must be mechanisms. The liberation of potassium during considered. Increasing experimental evidence is glycogenolysis inevitably occurs, but at a rate which becoming available that the ductus arteriosus does allows adequate renal excretion of potassium by the not close within a few minutes after birth. The maturing renal tissue. careful studies of lambs by Dawes et al. (1954) and that in that Born et al. (1956) at Oxford have shown http://adc.bmj.com/ Coexistent Hypocalcaemia and Hyperpotassaemia animal the closure takes place over hours, and is The biochemical abnormality observed in this dependent on changes in oxygen tension and the investigation was the coexisting hyperpotassaemia release of sympathetic amines. and hypocalcaemia. The danger of simultaneously The occasional observation of cyanosis of the rising potassium and falling calcium-ion levels in lower part of the body of newly born babies the blood was described by Guest (1952). Protec- stimulated Eldridge et al. (1954) to carry out oxygen tion of dogs against normally lethal concentrations saturation studies upon arterialized capillary blood of potassium may be provided by the intravenous from the right hand and foot of healthy newborn on September 29, 2021 by guest. Protected injection of calcium (Winkler et al., 1939). Modifica- human infants; 14 studies were made on 12 subjects. tion of the effects of potassium intoxication in Of the 14 studies, eight showed significantly lower children by the administration of calcium salts was values in the foot than in the hand. In all five claimed by Govan and Weiseth (1946). Latent studied from one to three hours after delivery the tetany in a group of adults with coexisting hypo- oxygen saturation of blood from the foot was potassaemia and hypocalcaemia was rendered significantly lower than in the hand, indicating the manifest by the slow intravenous infusion of presence of a veno-arterial shunt to the lower part potassium salts even though the final plasma potas- of the body. Three of the five infants studied from sium level did not exceed the usual normal range three hours to three days after birth showed lower (Engel et al., 1949). More recently Levine et al. blood oxygen-saturation values in the foot than in (1952) have claimed that hypocalcaemia may the hand. None of the four infants who were older actually potentiate the electrocardiographic signs of than three days showed significant oxygen-saturation hyperpotassaemia. None of these facts was con- differences. One baby who had a significant Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 155 difference at two hours which persisted at two As a possible explanation for a very curious days showed no difference between hand and foot phenomenon it is suggested that spasm spreading values by the fifth day. Should these studies be to the greater vessel and producing partial occlusion confirmed, then exchange transfusion is being merits consideration. Resolution of the physical carried out at a time when the ductus may be open signs might then follow partial withdrawal of the functionally and when it may be the site of a veno- catheter and relaxation of the vena cava. Sphincter arterial shunt. mechanisms exist on the great veins of some From this it is but a step to the fact that the mammals. The dog has one on the hepatic vein, increase in pressure in the right side of the heart and the common seal has one on the posterior which may occur during exchange transfusion may inferior vena cava (Harrison and Tomlinson, 1956). increase the right-to-left shunt through the ductus No reference can be found to the existence ofany such and give rise to visible cyanosis in the distal half of structure in the human embryo at any point in the body. The increased pressure might be the development. Spasm of the inferior vena cava of result of a weakened myocardium going into failure, animals may occur, however, as a reflex phenomenon of excessively rapid transfusion or of partial spasm in the absence of any recognizable sphincter. The of the great abdominal veins which would act fact that the vena cava of the horse could be made to normally as a blood reservoir. Such an explanation constrict by stimulating the abdominal sympathetic is not entirely satisfactory, however. If the cyanosis was recorded by Valentin (1839). Splanchnic were the result of a veno-arterial shunt through the stimulation can cause constriction of the inferior ductus, it is surprising that it appeared in the very vena cava (McDowall, 1938), and the portal vein early stages of operation, that it did not become can be made to constrict similarly (Burton-Opitz, progressively more noticeable and that it resolved 1913). Furthermore, Neil (quoted by McDowall, although operation was continued. Perhaps the 1956) has obtained records of post-ganglionic withdrawal of the catheter for a few centimetres was sympathetic activity in fibres supplying the superior responsible, as the blood flow which had been and inferior venae cavae. Such impulse discharge directed through the ductus venosus to the vena cava is markedly increased reflexly by such a remote areas close to the heart would then be subjected to the procedure as the perfusion of the carotid-body copyright. cushioning effect of the portal circulation. Even if with blood of low oxygen saturation. With spasm this were so, a major difficulty still remains. There of the vena cava in mind, radiological studies was no doubt that the superficial veins over the employing a contrast medium were planned for such front of the abdomen became much more obvious further cases as might be encountered, but none has and that they drained upward over the chest. They occurred. did not constitute convincing evidence of occlusion Even if both these explanations should be incor- suggested it. rect, the phenomenon, of which there may be milder of the inferior vena cava, but they http://adc.bmj.com/ Catheterization of the umbilical vein takes the unobserved degrees, reminds the paediatrician that catheter tip to the inferior vena cava at 12-14 cm. he is producing acute dynamic changes in a circu- from the abdominal wall (van Loghem et al., 1949). latory system which is undergoing simultaneous When obstruction is encountered at 10-11 cm., the adaptation to extra-uterine life. Following the catheter may have turned into the portal circulation occurrence of the second case the catheter tip has and the withdrawal of blood may be very difficult never been inserted for more than 7-8 cm. from the or even impossible. Catheterization of the ductus abdominal wall. The employment of less rigid

venosus is not easy, but from a knowledge of the catheter material may have some advantage (Tizard, on September 29, 2021 by guest. Protected length of polythene tube introduced into these two 1957). infants the catheter tips must have lain in the ductus venosus or in the portal circulation. 'The fact that Speed of Exchange. The development of signs of veins are capable of constriction may be observed cardiac failure during exchange transfusion is not by anyone who attempts to insert a cannula into uncommon, but, apart from the unknown impor- one without due care' (McDowall, 1938). The tance of the coexisting hyperpotassaemia and ductus venosus is a foetal vessel which is in process reduced calcium ion in Case 1, the other biochemical of establishing or maintaining functional closure at findings in the series were unassociated with cardiac the time when an exchange transfusion is being failure. The mechanical stress of exchange trans- carried out. Irritation by a catheter could be fusion must be considerable. When a 7 lb. baby expected to intensify the muscular constriction. The receives an 80 ml. per lb. body weight exchange he vessel is relatively short and it enters the inferior is subjected to a constant withdrawal and replace- vena cava. ment of from 3 % to 7% of his blood volume every Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 156 ARCHIVES OF DISEASE IN CHILDHOOD two to three minutes for 1 to 2 hours. This takes the puppies were subjected to additional stress place in a subject whose myocardium may be (barbiturate overdosage in one and exsanguination unhealthy before operation is begun and who may shock in another), however, they were less able to have other weak points in the circulatory system. face the challenge of rapid exchange transfusion. The spleen, for example, may rupture either spon- There are obvious differences between the animal taneously or during exchange transfusion. In 1949 experiment and the human operation. The experi- an exchange transfusion by the umbilical route was ment employed healthy puppies receiving their own carried out by one of us (J. W. F.) on a severely warm heparinized blood by the femoral artery, affected baby of 5 lb. weight. Twenty-ml. aliquots whereas the operation is carried out on human of blood were used and all seemed well until 380 ml. infants who have been the victims of a pathological had been exchanged. The infant then collapsed process for some weeks and possibly involving the suddenly and died in a few moments. The catheter circulatory system, and who receive cool or cold was clamped in situ, and at necropsy its tip was found stored citrated blood by the portal circulation. in the inferior vena cava near the right atrium. The Whatever the part played by excessive speed in the right side of the heart was extremely dilated. No production of symptoms during exchange trans- other abnormality was found and the death may be fusion, the surgical principle of gentleness in attributed to the author's inexperience. operating is likely to be less upsetting to an infant The deterioration observed so commonly by than haste and undue manipulation. Where signs Walker and Neligan (1955) was thought to be of distress appear they frequently subside if the baby unrelated to the initial condition of the infants, the is left undisturbed for five or ten minutes, and if birth weight, technical difficulties encountered or the cardiac failure is definitely present a small venesec- rate of exchange. Yet at least one of their subjects tion may be carried out with advantage. Clinical was so delicately balanced that the injection of only deterioration may take place, however, in the 10 ml. at one point in an exchange transfusion absence of the classical signs of cardiac failure. The dramatically converted an apparently well baby into descriptive term 'shock' has been applied here to a dead one. The effect of the too-rapid transfusion those infants who become cold, pale and limp, who of anaemic patients was described by Starling (1918) develop varying degrees of abdominal distension as being like an overloaded heart-lung preparation. and whose breathing may be accompanied in copyright. Venous pressure rises and cardiac output falls. expiration by a faintly audible, murmuring whine. Referring to what Wiener (1943) has described as The pallor may be so striking that intraperitoneal 'speed shock', the British Medical Journal (1955) haemorrhage is suspected. The condition was points out that the circulatory collapse is related. recognized by Walker and Neligan (1955), who also not to the properties of the stored blood, but to the described it as shock and who recommended the total volume given and the speed of administration. giving of more blood as treatment. In the present The ability of children to tolerate relatively faster investigation the clinical disturbance was unaccom- http://adc.bmj.com/ transfusion than adults was mentioned by Andrews panied by a single biochemical pattern. and Coleman (1957), but their subjects were aged 4 years or more. Increasing Blood Viscosity. Variation in the The need for care and experience in carrying out viscosity of the blood influences the load carried exchange transfusion has been stressed by Philipsborn by the heart (Whitby and Britton, 1953). Any et al. (1956). They found from the literature that most increase in blood viscosity is naturally harmful when exchange transfusions were carried out in from one it increases the work thrown on a heart with reserves on September 29, 2021 by guest. Protected to two hours, and decided to investigate the effect of strength seriously diminished by disease (Lcncet, of rapid exchange transfusion in pups. The opera- 1942). The immediate cause of death from haemo- tion was carried out on healthy mongrel pups lytic disease within 12 to 24 hours of birth is cardiac through the femoral artery and employing their own failure, for which the best immediate treatment is heparinized blood. They discovered that much larger venesection and oxygen administration (Mollison, aliquots of blood could be used with safety than had 1956). The viscosity of blood increases with been anticipated, and that the vascular trees of increase in the haematocrit. For these reasons puppies could be expanded or contracted by as much the wisdom of using packed or sedimented as 25% without significantly altering the venous or red cells for exchange transfusions may be arterial pressures or provoking changes in the ECG. doubted where the infant's original haematocrit Circulatory equilibrium could be maintained is low and the haematocrit of the donor blood is under challenges far exceeding those which ordinarily appreciably higher. The transfusion of anaemic occur during exchange transfusion. When two of patients was found by Evans (1942) not to increase Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from CLINICAL AND BIOCHEMICAL CHANGES DURING EXCHANGE TRANSFUSION 157 whole-blood viscosity, but he transfused with whole ally controlled water-bath and through which the blood and the procedure was not comparable in donor blood was heated briefly on its way to the volume or speed with exchange transfusion. No baby. The blood reached the infant at a temperature observations on changes in blood viscosity during of 96°-100° F. Following this innovation the rectal exchange transfusions with whole blood and with temperatures of further infants studied were main- sedimented cells have been found. If the viscosity tained, and their condition was claimed to be better does in fact rise with a rising haematocrit, then this than that of the infants who had received cool blood. would provide an objection to the routine exchange A dramatic description of cardiac arrest during of the profoundly anaemic patient's blood with exchange transfusion was given by Pew (1955). An aliquots of sedimented cells. It is acknowledged, infant with moderately severe haemolytic disease however, that if high-output cardiac failure is to be received an umbilical exchange transfusion with very avoided in such infants the haemoglobin value may fresh citrated blood. Shortly after 350 ml. had been need to be raised to some extent. This may be done exchanged the heart stopped suddenly. The infant's without employing sedimented cells for the whole chest was opened and the heart massaged. Normal operation, and it should be done slowly. Any cardiac rhythm was restored after about two residual anaemia may be corrected later by scalp- minutes. The exchange transfusion was continued vein transfusion when the patient's immediate and the exposed heart kept under observation. As survival has been assured. At the Simpson Memorial blood was injected the heart was noted to slow and Maternity Pavilion emphasis has always been placed to be 'definitely cool'; indeed the bradycardia upon leisurely exchange with whole blood and upon became so profound that further cardiac massage the judicious maintenance of a negative balance and the intracardiac injection of adrenaline were between withdrawal and replacement in severely required. Normal rhythm was again restored; the affected babies. Rising blood viscosity would be exchange transfusion was carefully completed and unlikely to bear any relationship to the clinical the chest repaired. The total serum calcium con- disturbance of mildly affected infants during centration shortly after cardiac arrest was only exchange transfusion. The blood viscosity of such 5 7 mg. per 100 ml. The baby showed some

cases may in fact fall during operation. twitching when convalescent. The calcium was not copyright. In practice, however, there is probably less recorded, but the sign disappeared when calcium difference than might be thought between the blood gluconate was given. No information was pro- from which the supernatant plasma has been vided about the speed of operation or where the decanted and whole blood which is allowed to stand tip of the catheter lay. Cooling was considered to undisturbed throughout the operation. Recent be the possible precipitating factor. The first bottle observations on blood containers in Edinburgh of blood had been adequately warmed, and the (Cumming, 1957) have shown how very difficult it is crisis developed soon after the second, unwarmed, to maintain anything like an even suspension of cells bottle had been brought into use. http://adc.bmj.com/ in the standard glass transfusion bottles even when The local application of cold to the front of the these are intermittently inverted. chest produces a slow heart rate, diminished systolic output and increased blood pressure (McDowall, Cooling 1956). Extracorporeal cooling of dogs down to Chilling of the baby during exchange transfusion temperatures of 260 C. will not precipitate cardiac has been thought to be responsible for some of arrest, but the injection of very cold blood close to the abnormalities observed. The rectal tempera- the heart can provoke auricular fibrillation (Delorme on September 29, 2021 by guest. Protected tures of infants receiving blood at 70°-80° F. have 1957). This would be particularly dangerous if it been shown to fall from 97°-99° to 94°-96° in 21 occurred in an infant with a devitalized myocardium cases studied by Marting et al. (1955). Cooling of and whose heart was receiving rapidly recurring this degree might occur in newborn infants exposed influxes of 10-20 ml. of blood under pressure. on a table for two hours unless careful precautions such as those described by Corey et al. (1955) are Autonomic Stress taken to avoid it. Four of the 21 infants, however, The catheterization of the umbilical vein and the showed signs of shock after about 250 ml. had shunting to and fro of blood in the portal circulation been exchanged. Their blood was noted to be may be more disturbing than has been thought poorly oxygenated, and this was attributed to previously. Walker and Neligan (1955) gained the hypothermia. Two of the four babies died. As a impression that excessive traction on the umbilical result of their investigation Marting et al. produced cord during manipulation of the catheter produced a glass helix which was immersed in a thermostatic- vomiting. There is no doubt that the prodding of Arch Dis Child: first published as 10.1136/adc.33.168.142 on 1 April 1958. Downloaded from 158 ARCHIVES OF DISEASE IN CHILDHOOD obstructions within the portal circulation makes the have to sacrifice their occasional opportunities of baby retch and he commonly regurgitates. Disten- carrying out the procedure, but many would be sion of the portal circulation by rapid transfusion prepared to do so for the sake of the child. In the may also precipitate this trouble. Such reflex towns around Edinburgh a number of hospitals stimulation was undoubtedly the cause of retching make a practice of sending the affected mother to in this small series. Operations in the upper the Simpson Memorial Maternity Pavilion for abdomen in relation to diaphragm and peritoneum delivery, and for treatment of the child should that may provoke hiccup, vomiting and shock. Exchange be necessary. By doing so they assure the infants transfusion evokes dynamic changes in a region of very early treatment by a team which possesses richly supplied with both afferent and efferent reasonable experience. autonomic nerves and may be expected to give rise to some disturbance. Conclusions Various clinical disturbances may be observed Inexperience during exchange transfusion in the infant suffering The experience of those conducting exchange from haemolytic disease. Exchange transfusion transfusions varies widely. There is more to the produces considerable change in the patients' plasma procedure than exchanging 10 ml. aliquots of blood. electrolytes. The citrate level increases, potassium In a surgical team it is unlikely that an operation frequently increases and the calcium-ion level falls carrying a comparable mortality would always be irrespective of the total serum calcium. The changes left to the house-surgeon or an inexperienced in serum electrolytes were shared by infants who registrar. Yet junior staff may be left unsupervised were disturbed and by those who showed no to carry out an exchange transfusion in the belief abnormality. The depression of calcium ion can be sometimes held by senior staff inexperienced in this neither prevented nor corrected by injectingcalcium procedure that normal skill and common sense gluconate in the dose employed in this study. Other are all that is required. The apprenticeship to be possible causes of clinical disturbance have been served by the would-be operator of exchange trans- suggested. Evidence for them has not been sought nor easy, and even after many in this study. They include such factors as inter- fusion is neither short copyright. successes the experienced may be humbled by failure. ference with the circulation during the period of It is interesting to note that Walker and Neligan post-natal readjustment, excessive speed ofexchange, (1955) had a low mortality, and yet Walker (1955) changing blood viscosity, manipulation of the in a personal communication stated that, taking the catheter within the abdomen, the injection of cool country as a whole, the problem of unexpected death blood and, above all, inexperience on the part of the was more common than he had previously thought. operator. This suggests that where both skill and experience We wish to express our thanks to Professor R. W. B. http://adc.bmj.com/ were available the mortality was lower than in other Ellis and Dr. C. P. Stewart for their encouragement areas where experience was less. Precisely this view during this work, and to the former for his constructive- has been expressed by Walker and Mollison (1957). criticism of the paper. We are grateful also to those They have shown from national figures that an registrars who took samples of blood and kept careful clinical records during some of the exchange transfusions. appreciable number of infants dying of haemolytic The biochemical data included in this paper formed disease had received exchange transfusions which part of the Ph.D. thesis submitted successfully by H. S were inadequate in volume, and that the actual to the University of Edinburgh.

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