ch. 36 hemolytic diorders/congenital anomalies Flashcards
hemolytic disease of the newborn
1) associated with alloimmunity, it is the result of antigens expressed by fetal erythrocytes crossing the placenta, entering the maternal circulation, and stimulating the maternal immune response (antibody antigen fights)
2) occurs most frequently with:
(a) ABO incompatibility - MOST COMMON
- ex: mom (O+), father (AB+_)
(b) Rh(D) incompatibility - SECOND MOST COMMON
- ex: mom (O+), rhogam (28 weeks)
3) review:
(a) four major blood group: A,B,AB,O
(b) the Rh factor: person who is Rh (-) means she/he does NOT have the Rh(d) antigen
TIP:
- universal recipient: AB+
- universal donor: O-
Hemolytic disease of the newborn: Rh incompatibility
1) Rh positive offspring of an Rh-negative mother are at risk
2) mother forms antibodies (called maternal sensitization) that then destroy fetal red blood cells (hemolysis)
3) results can be mild (infant hyperbilirubinemia) or severe (erythroblastosis fetalis, hydrops fetalis)
Hemolytic disease of the newborn: ABO cincompatibility
1) Fetal blood type is A,B, AB and mother is O
2) naturally occurring anti-A and anti-B antibodies are transferred across the placenta to the fetus
3) of the 20% of newborns who have ABO incompatibility, only 5% have clinical effects
4) if the hemolysis is severe, other treatment options include exchange transfusions and intravenous (IV) immunoglobulin
Hemolytic disease of the newborn: other causes of hemolysis
1) Nonimmune hemolysis: seen with infections such as TORCH are bacterial infections
- Toxoplasmosis, other, rubella, cytomeglia, herpes
2) glucose 6 phosphate dehydrogenase (G6PD) deficiency:
- common among neonates whose genetic heritage comes from Africa, Asia, the Mediterranean, and the Middle east
- G6OD deficiency is a LACK of the G6PD enzyme that protects RBCs from reactive oxidative species and destruction
- male offsprings > female offsprings affected
- hyperbilirubinemia can be SEVERE (jaundice)
3) other metabolic/inherited conditions cause hemolysis and hyperbilirubinemia in the newborn:
- galactosemia
- crigler-najjar disease
- hypothyroidism
- gilbert syndrome
- thalassemia
- elliptocytosis
- spherocytosis
hemolytic disease of the newborn
1) care mgmt:
- important to determine the blood type and rH factor of pregnant women early in gestation or DURING the preconception period (blood sample)
- Rh immune globulin: commercial preparation of passive antibodies against the Rh factor; destroys any fetal RBCs in the maternal circulation and blocks maternal sensitization and antibody production
- TIP: give to ALL RH negative mothers at 28 weeks of gestation; within 72 hours after delivery, after an invasive procedure, and any time there is a risk of fetal maternal hemorrhage
2) critical testing:
- indirect Coombs test
- anti-D titer
- MCA-PSV
- cord blood at birth
- Coomb’s test
- serial bilirubin
- in some cases of severe hyperbilirubinemia, exchange transfusion may be needed (if phototherapy doesn’t work)
congenital anomalies
1) structural or functional abnormality that occurs during intrauterine life and is identified prenatally, at birth, postnatally, during infancy, or thereafter
2) can be caused by genetic or environmental factors but up to 50% do not have an identifiable cause
3) WHO (2022) estimates that 6% of all infants are born with a birth defect, and approximately 295,000 of those infants will die as a result
4) factors r/t to incidence of congential anomalies:
- genetic factors
- socioeconomic factors
- demographic factors
- environmental factors
- maternal health factors (nutritional status, diabetes, infections)
5) most common, major congenital anomalies that cause serious problems in neonates are as follows:
- congenital heart disease
- neural tube defects (spina bifida)
- cleft lip or palate
- clubfoot
- developmental dysplasia of the hip
congenital anomalies: congenital cardiac defects
1) CHD: structural anomalies of the heart or intrathoracic vessels that are present at birth and affect cardiac function
2) most common type AND leading cause of death from congenital anomalies
3) screening programs are effective in detecting CCHD and in reducing early infants due to CCHD (50 tests)
4) major role of the nurse: assess infants for abnormal findings
congenital anomalie: CNS (neural tube defects)
1) encephalocele & Anencephaly (absence of brainstem)
2) spina bifida:
- 3 most common types: occulta, meningocele, myelomeningocele
3) meningocele;myelominingcele
4) hydrocephalus
5) microcephaly (ZIKA virus contributes)
congenital anomalies: respiratory system
1) choanal atresia:
- most common congenital anomaly of the nose
- congenital blockage of the posterior nares by a bony or soft tissue obstruction (baby trouble breathing, turning blue)
2) congenital diaphragmatic hernia (CDH):
- defect in the formation of the diaphragm (abdominal organs are displaced into the thoracic cavity causing interference with development of the lungs
- etiology unknown
- diagnosis
- treatment: direct towards what it is
congenital anomalies: GI
1) cleft lip and palate (orofacial clefts)
2) esophageal atresia (EA) and tracheoesophageal fistula (TEF)
3) omphalocele and gastroschitis
4) gastrointestinal obstruction
- contortion intestine
- meconium ileus
5) anorectal malformations
- imperforate anus
congenital anomalies: hip/foot
1) developmental dysplasia of the hip:
(a) 3 degrees of DDH:
- acetabular dysplasia (preluxation)
- subluxation
- dislocation
2) assessment
3) diagnosis
4) treatment
5) foot deformities:
- congenital clubfoot (talipes equinovarus): newborn assessment, move foot midline (easy - nothing wrong, difficult - club foot)
- metatarsus adductus
congenital anomalies: GU
1) hypospadias:
- encompasses a range of penile anomalies associated with an abnormally located urinary meatus
2) bladder exstrophy
3) ambiguous genitalia
congenital anomalie: inborn errors of metabolism
1) biochemical genetic disorders that result from defects in single genes; the majority of disorders are inherited as autosomal recessive conditions; causes a blockage in a critical metabolic pathaway
- phenylalanine hydroxylase deficiency (PAH)
- galactosemia
- congenital hypothyroidsm (CH)
congenital anomalies care mgmt
1) assessment:
- prenatal
- postnatal
2) interventions:
- newborn care (discredited toward anomalie)
- parents and family support
- genetic evaluation and counseling (extensive r/t risk of having another baby)
