Hemolytic disease of the new born (HDN) HYPERBILIRUBINEMIA

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Hemolytic disease of the new
born (HDN)
HYPERBILIRUBINEMIA
Dr. Nihad Al Doori
5th lecture
Objectives:
• At the end of the lecture the student will be able
to:
1. Describe the concept of bilirubinemia
2. Recognize the causes of bilirubinemia
3. Evaluate the prognosis of the condition of the
infant receiving the different types of therapy for
hyperbilirubinemia e.g. phototherapy and
exchange blood transfusion
4. Develop awareness for the serious side effects of
hyperbilirubinemia
5. Recognize the need of the parents for support
and comforting
• Hyperbilirubinemia:
Refers to the increased level of
accumulated bilirubin in the blood &
characterized by jaundice or icterus.
• Normally there is balance between the
destruction of RBCs and the use or secretion
of it’s products
Causes of Hyper bilirubinemia:
1. physiologic (developmental) factors such as,
prematurity
2. An association with breast-feeding or breast
milk
3. Excess production of bilirubin e.g. hemolytic
disease, biochemical defects, and bruises
4. Disturbed capacity of the liver to secrete
conjugated bilirubin, e.g. enzyme deficiency,
bile duct obstruction.
5. Combined over production and under
secretion e.g. sepsis
6. Some disease states e.g. hypothyroidism,
galactosemia, and infants of diabetic
mothers
• Anemia in this condition is caused by the
destruction of the RBCs which stimulate the
↑ production of +++ RBC leading to more
hemolysis.
• Hyperbilirubinemia in the first 24hrs after birth
result of:
• Erythroblastosis fetalis in which there is an
abnormally rapid rate of RBCs destruction.
The major cause of erythrocyte destruction is:
Isoimmunization primary Rh & ABO
incompatibility.
Blood incompatibility
• Antibodies in the serum of a blood group will
produce agglutination or clumping reaction
when mixed with antigens of a different blood
group.
• 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.
Rh incompatibility (Isoimmunization)
• The blood group consists of several antigens,
the Rh +positive (presence of antigen) & the
Rh-negative (absence of the antigen).
• If the Rh blood types are the same in the
mother & the fetus NO problem
• If the Rh blood type of the mother is Rh +
positive & the infant is Rh- negative also NO
problem
• Difficulty will occur when the blood of the
mother is Rh -negative & the infant is Rh +
positive, the Rh antigen from the fetus will
cross the placenta though minute break in the
vessels
• The mother’s natural defense mechanism will
produce anti Rh antibodies in respond to the
alien RBCs of the Rh positive from the fetus.
• This usually occurs during labor, so this first
baby is not affected.
• During subsequent pregnancies with Rh
positive fetus, the previously formed maternal
antibodies enter the fetal circulation and
attack and destroy the fetal erythrocytes
• In the severe cases of Erythroblastosis fetalis
hydrops fetalis the
progressive hemolysis causes:
• Fetal hypoxia
• Cardiac failure
• Generalized edema
• Effusion of the pericardial, pleural &
peritoneal spaces
• Fetus may be delivered stillborn or in severe
respiratory distress
• Complications of hyperbilirubinemia:
Uncojugated bilirubin is highly toxic to the
neurons bilirubin encephalopathy
(Kernicterus) sever damage of the brain,
which occurs when the serum concentrations
reaches toxic levels & crosses the blood-brain
barrier in the newborn causing irreversible
brain damage.
Signs of bilirubin ncephalopathy:
•
•
•
•
•
•
Rigid extension of all limbs
Opisthotonus
Fever
Irritability
Cry
Seizures
Diagnostic evaluation:
• Amniocentesis & analysis of bilirubin levels in
the amniotic fluid if it is increasing then there
is progressive hemolysis
• Rh-antibody tiers in the maternal blood can be
evaluated (indirect coomb,s test)
• can be confirmed by detecting antibodies
attached to the circulating RBCs in the infant’s
blood (direct coombs test).
Management & Treatment:
• The aim is prevention of isoimmunisation by:
• Administration of RhO — Immuno-Globin
(Rh.OGAM) injection to all unsensataised Rh
negative mothers after delivery or abortion of
an Rh positive infant or fetus
• The injection to be given within 72 hrs after
delivery.
• Injection of anti - Rh antibodies destroy the
fetal erythrocytes passing into the maternal
circulation before they can exert their
immunogenic effect, this injection has to be
given after the first delivery to be repeated
after subsequent ones
• Administration of the injection at 26 — 28
weeks of gestation is also recommended to
decrease antibody formation but it is not
effective on the already formed antibodies.
• Physiologic ( NON pathologic )jaundice:
Is the most common cause and is relatively
mild self-limited. It appears 2nd or 3rd day
and peaks on 3rd or 4th and decreases on the
5th day to 7th day
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•
•
•
Causes are :
Higher concentration of circulating RBCs
Immature liver
Absence of intestinal flora in the NB which is
responsible for reducing urobilinogen to be
excreted by feces.
The ↓ intestinal motility if feeding is delayed
Therapeutic management:Primary goals are to prevent bilirubin
encephalopathy.
Early Initiation of br. Or bottle feeding.
• Photo therapy → photoisomirization
• Florescent light spectrum .
• Exchange transfusion (hemolytic disease).
• Use of Phenobarbital (hemolytic disease )
• Early initiation of feeding (breast feeding) if
bilirubin is 17mg /dl stop breast feeding for 24 hrs
and resume when it decreases.
Exchange transfusion:
this will help to:
1. Remove the sensitized RBCs
2. Decrease the serum bilirubin level to prevent
Kernicterus
3. Correct anemia
4. Prevent cardiac failure
Indications for exchange transfusion:
• Positive direct coomb’s test
• Hb<12g/dl
• Bilirubin level of 20 mg/dl in the full term
infant or 15 mg/dl in the premature infant
• An infant born with Erythroplastosis fetalis is a
candidate for immediate exchange transfusion
with fresh whole blood
• Small amounts of the infant’s blood
(2-10 ml) of the infant’s blood is removed &
replaced with compatible blood
• Amount of blood used is double the
newborn’s blood volume(85 ml/Kg) 500ml
• Sterile procedure is used to introduce the
umbilical catheter and is passed into the
inferior vena cava
• (5-10)ml of the infants blood is withdrawn
within 15 — 20 sec
• the same amount of blood is withdrawn from
the donor blood & infused into the infant’s
circulation within 60 — 90 sec
• Calcium gluconate is given after each 100 ml
of blood transfusion to prevent hypocalcaemia
• This procedure will replace 55% of the
newborn’s blood
Phototherapy
• Phototherapy, in which the baby is placed
under a fluorescent light are placed 12 to 30
inches , lowers the bilirubin in the neonate's
blood. Term newborns are generally
scheduled for phototherapy when the total
serum bilirubin level rises to 10 to 12 mg/dL at
24 hours of age;
Fibro optic blanket
It is ideal for home care. The infant is
undressed except for a diaper so as
much skin surface as possible is
exposed to the light
Nursing considerations:
• Recognition of hyperbilirubinemia is very
important antenatal & perinatally by history
assessment & looking for early signs of jaundice
in the newborn
• If exchange transfusion is needed the nurse will
reassure the parents
• Assist the physician with the procedure by
keeping accurate records of the amount of blood
given & removed
• Observing the vital signs
• keeping the infant warm.
• Observe the umbilical catheter & is kept covered
with sterile gauze after the procedure is finished
in case another exchange is needed.
Thank You
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