By:Marvi Mae Jimena

Rosean Marvi Joy M. Yunsay

ABO INCOMPATIBILITY

ABO blood group

ABO Incompatibility

ABO incompatibility is  common and generally mild

type of hemolytic disease in babies

In most cases of ABO incompatibility, the maternal

blood type is O and the fetal blood type is A.

It may also occur when the fetus has type B or AB

blood.

The reticulocyte count (immature of newly formed

red blood cells) is usually elevated as an infant

attempts to replace destroyed cells.

Pathophysiology

Etiology:Unkown

Predisposing and precipitating factors :

MiscarriageTraumaBirth(especially during placental

separation)

Mixing of maternal and fetal blood

Antibodies against foreign blood type is formed

Antibodies circulate through the fetal circulation

Hemolysis of the baby’s blood cells

Pathophysiology

• ABO antibodies are of large (IgM) class and do not

cross the placenta.

• Hemolysis of blood begins AT BIRTH, when the

blood and antibodies are exchanged during the

mixing of maternal and fetal as the placenta is

loosened

• destruction of red blood cells may continue for up

to 2 weeks of age.

AN INFANT OF AN ABO INCOMPATIBILITY IS NOT BORN ANEMIC AS IS THE Rh SENSITISED CHILD.

 

WHY?

This may be because the receptor sites for anti-A or anti-B antibodies do not appear on red cells until late in fetal life. Even in the mature newborn, the direct Coomb’s test may be only weakly positive because of the few anti-A or anti-B sites present.

PRETERM INFANTS DO NOT SEEM TO BE AFFECTED.

WHY?

Progressive jaundice within the first 24 hours of life. Jaundice occurs because as red blood cells are destroyed, indirect bilirubin (fat-soluble and cannot be excreted from the body) is released.

Brain damage and Kernicterus can occur

Assessment

Progressive hypoglycemia. An infant needs to use glucose stores to maintain metabolism in the presence of anemia.

Decrese in HgbTachypneaDyspneaTachycardia

Assessment

Exchange Transfusion The procedure involves alternatively

withdrawing small amounts (2-10 ml) of infant’s blood and then replacing it with equal amounts of donor blood via umbilical vein catheter

Procedure lasts 2-3 hoursremoves approximately 85% of sensitized

red cells in ABO incompatibility.

Management

Initiation of early feeding

Bilirubin is removed from the body by being incorporated into feces. Therefore, the sooner the bowel elimination begins, the sooner bilirubin removal begins.

Management

Phototherapy

Exposure to light triggers the liver to assume its function which is to process bilirubin.

Additional light supplied by phototherapy speed the conversion potential of the liver.

Management

Infant’s eyes must be covered under

bilirubin lights because the retina can be

damaged.

Infants should also wear a gonadal shield

Stools are often bright green because of

excessive bilirubin. They are also loose and

frequently irritating to the skin.

 

POINTS TO REMEMBER during PHOTOTHERAPY 

Urobilinogen formation may cause dark-

colored urine.

Monitor temperature.

Explain importance to parents.

Turn the infant every two hours to expose

different parts of the infants body

Monitor I&O.