EXCHANGE BLOOD TRANSFUSION –
AIMS, INDICATIONS, HAZARDS
AND GENERAL INSTRUCTION
EXCHANGE BLOOD TRANSFUSION
An exchange transfusion is a method of treating certain blood diseases or abnormalities in the newborn child by the exchange of the majority of the circulating blood. The term replacement transfusion and exsanguination have also been used.
Aims
1. To remove excess bilirubin from the body of the infant and prevent kernicterus
2. To enhance haemoglobin level without appreciable changes in the blood volume
3. To remove the sensitized blood cells in the affected children
An exchange or replacement blood transfusion may be carried out on a newly born Rh positive infant born to a Rh negative mother and suffering from haemolytic disease. Exchange blood transfusion is the only effective therapy for the majority of cases of haemolytic diseases of the newborn. This method permits regulation of the blood volume, remove cells susceptible to haemolysis and controls hyperbilirubinaemia. Exchange blood transfusion may be performed in adults suffering with severe anaemia in which the amount of blood is removed from the patient which equals to the amount introduced. This prevent circulatory overload and other related complications in these patients.
Indications
These may be divided into two categories namely haemolytic and non-haemolytic conditions.
1. Haemolytic conditions
a. Rhesus incompatibility
– Severe anaemia – Hb below 8 gm%
– Hydrops foetalis
– Impending heart failure
– Previous obstetric history of seriously affected infants e.g., siblings with hydrops foetalis or severe hemolytic disease provided the Coomb’s test is positive in the present pregnancy.
– Maternal anti Rh titre more than 1/64 and father homozygous D.
– Induced delivery of sensitized premature infant
– Cord blood haemoglobin below 13 gm% with positive direct test of the cord cells.
– Cord blood bilirubin of 4mgm or more and rapid rise of indirect bilirubin after birth. (serum bilirubin approaching the dangerous level of 20mg% at any time).
– Serum albumin rising more than 1mg% or approaching 10mg% at 24 hours. 14mg% at 148 hours, 17 mg% by 72 hours.
b. ABO incompatibility, mainly to prevent kernicterus
c. G 6 PD deficiency
d. Jaundice from administration of drugs to newborns (vitamin K, Sulfisoxazole, salicylates etc.).
e. Infections as evidenced by positive blood culture, pus cells in the urine and polymorphonuclear cells in the gastric aspirate.
f. Impending Kernicterus
g. Diffuse intravascular coagulation
2. Increase in Reticulocytes
HAZARDS OF EXCHANGE TRANSFUSION
Complications following exchange transfusion may occur during the procedure (early) or after 6 to 8 weeks (late)
Early complications
1. Cardiac arrest which result from acidosis because of low pH of citrate blood. Use of heparinized blood is recommended to prevent this complication.
2. Hyperkalaemia due to the use of old stored blood with a high level of potassium
3. Tetany from the use of citrated blood
4. Air embolism
5. Oligaemic shock on giving anaemic blood or administration of much less blood than what is removed from the patient
6. Septicemia due to introduction of infection into the blood stream during the procedure
7. Transfusion reaction from incompatible blood transfusion
8. Haemorrhagic problems from heparinized blood used for the transfusion.
9. Respiratory distress
10. Heart failure
11. Cyanosis
12. Necrotizing enterocolitis
Late Complications
1. Anaemia
2. Portal vein thrombosis
3. Portal thrombosis
Procedure
1. Strict surgical asepsis must be observed
2. After preparation, the infant is draped. In newborn the umbilical vein is used. When this is not available femoral vein may be used. Umbilical stamp is exposed and a small umbilical catheter is passed into the umbilical vein, which is introduced to a distance of 6 to 8 cm.
3. Venous pressure is estimated before starting the procedure as well as at frequent intervals. (normal 10 cm of water at rest).
4. Initially about 50 ml of blood is withdrawn and 20 ml is introduced to keep a deficit of 30 ml of blood throughout the procedure (deficit exchange). 20 ml of blood is withdrawn and equal amount of donor blood is introduced during subsequent transfusions.
5. An accurate record of input and output of blood is maintained throughout the procedure to prevent circulatory overload.
6. At the end of procedure, the deficit – 30 ml – blood should be added to equalize the input and the output.
7. The amount of blood to be replaced is twice the blood volume of the infant (normal blood volume is about 35-100 ml/Kg). this may result in exchange of about 35% of baby’s blood volume. This will also ensure an exchange of erythrocytes that is 85% to 90% effective.
GENERAL INSTRUCTIONS
1. Explain the procedure to the relatives and reassure them.
2. The blood should be cross matched properly.
3. In Rh incompatibility, the transfusions are performed with group O Rh negative blood, whereas in ABO incompatibility and G6 PD deficiency disease the procedure has to be performed with the same ABO and Rh groups of the baby.
4. The blood should be as fresh as possible and it should never be more than 5 days old.
5. On no account the procedure should be hurried. A minimum time of 1 and half hours should be allowed. Take 3 to 5 minutes for the introduction of each 20 ml of blood. The rate of giving blood must be both slow and consistently even.
6. The venous pressure should be assessed from time to time and a careful watch is kept against overloading.
7. The individual exchange amount should not exceed 20 ml at a time. In premature infants, this amount should be even less.
8. All apparatus should be flushed from time to time with heparinized saline.
9. Donor blood preserved in ACD solution has a low pH and this can cause the danger of metabolic acidosis. It is recommended that one milli-equivalent of sodium bicarbonate be given for every 100 ml of blood transfused. It is desirable to estimate the acid-base ratio both before and after the transfusion.
10. Because of the risk of tetany from the use of citrated blood, 1 ml of calcium gluconate in 10 percent solution can be given for every 100 ml of blood transfused.
11. Estimate the serum bilirubin everyday for the first 5 days in order to assess the need for a repeat exchange transfusion to get rid of excess of circulating bilirubin and thereby to prevent kernicterus.
12. In case of heparinized blood, 0.5 to 1 mg of protamine sulphate is given 1M at the end of the transfusion.
13. If there are signs of cardiac or respiratory distress the exchange transfusions should be immediately discontinued.
14. The nurse must be alert to the fact that a significant risk of morbidity and mortality risk of 0.1 % to 1% exist with exchange transfusion. It is time consuming and expensive as well.
15. After the transfusion, observe closely for umbilical vessel bleeding, redness or inflammation of the cord that suggests infection, and changes from normal in vital sign.
16. The infant needs dextrostix assessment for about 2 hours and bilirubin levels monitored for 2 or 3 days after the transfusion to ensure that the level of bilirubin is not rising again and that no further transfusion is necessary.
17. Erythropoietin may be administered to increase new blood cell growth and prevent extended anaemia.