HemeOnc Flashcards
Types and breakdown of Hgb in newborn blood
(December 2021)
HbF (fetal, α2/γ2) and HbA (adult, α2/β2) with the latter ~6-40% depending on time relative to transition from predominantly fetal to adult Hgb
HbSS disease - what is it from Hgb standpoint and how do pRBC transfusions relative to newborn screen collection affect screening results
(December 2021)
Point mutation in β-globin gene where none are normal, so they lack HbA (α2/β2) and only have HbF and HbS. If transfused pre-PKU draw then could pick up HbA and be falsely negative. Recommend repeat 90 days post-transfusion or if collected <33 WGA, because preterm infants have less HbA inherently.
Maternal medications that can increase the risk of early VKDB?
(December 2021)
Anticonvulsants (ie phenobarbital, phenytoin, carbamazepine), anticoagulants, and anti-TB drugs
Time of onset and details of early v classic v late VKDB?
(December 2021)
-Early: first 24h; often severe & life-threatening. 25% ICH, cephalohematoma, subgaleal, intra-thoracic, intra-abdominal, GI tract, umbilical cord
-Classic: 2-7d; umbilical stump bruising/bleeding, circ site, GI tract, nose, rarely ICH
-Late: 2 wks- 6 mos; 30-60% ICH; generally exclusively breastfed infants who did not receive IM Vitamin K or malabsorptive disorders. Skin/GI tract bleeds also possible. Of note, oral VK helps with early and classic but not late onset VKDB
Diagnostic criteria for VKDB
(December 2021)
(i) PT greater than or equal to 4x control (ii) normal or increased platelets (iii) normal fibrinogen and degradation products (iv) normalization of PT after VK administration
Types of exchange transfusion, amount of blood volume replaced and % blood volume exchanged
(December 2021)
-partial volume: aims to modulate infant’s Hct while maintaining their blood volume ie normal saline for polycythemia with hyper viscosity syndrome
-single volume: replaces ~80 mL/kg of blood with ~60% of blood volume being exchanged. ?Maybe fewer side effects but not recommended over double due to risk:benefit re: reducing kernicterus
-double volume: replaces ~160 mL/kg of blood with ~85% of blood volume being exchanged.
Potential complications from exchange transfusion
(December 2021)
-hypotension, metabolic acidosis
-A/Bs
-arrhythmias
-hypocalcemia, hyperkalemia
-hypoglycemia
-NEC
-coagulopathy
-thrombocytopenia
-infection, air embolism
What is the most common germ cell tumor (GCT) in neonates? Primary treatment? Monitoring post-treatment?
(March 2022)
-teratoma
-postnatal surgical resection in any site
-Recurrence is low even in tumors with yolk sac or malignant components
-monitor serially with exam, imaging, and serum AFP levels and in rare case of recurrence then cisplatin or carboplatin-based chemotherapy is used
Fetal/Neonatal alloimmune thrombocytopenia (NAIT) or (FNAIT)
-Pathophysiology
-Clinical presentation
-Predictor of ICH in subsequent pregnancy
-Mgmt
(May 2022)
- incidence ~1/1000 and is caused by maternal production of maternal alloantibodies against fetal platelet antigens inherited from the father. Transplacental transport of these antibodies can cause fetal platelet destruction and mild to severe thrombocytopenia. In >90% white patients, caused by Ab against HPA-1a. Unlike Rh(i), this can occur in the first pregnancy
-presents with petechiae, ICH occurs in 0.2-1 in 10k live births and 10% of pregnancies affected by FNAIT
-Only predictor is history of ICH in a sibling with FNAIT
-Can use cfDNA to get fetal platelet genotype, IVIG if high risk can decrease ICH, maternal antenatal tx less risky and aims at reducing fetal thrombocytopenia/ICH. Tx mom with IVIG +/- prednisone if hx early ICH in sibling. No optimal evidence-based mode of delivery.
The formula for partial exchange transfusion volume for, say, hyper viscosity syndrome?
(July 2022)
Partial exchange volume = [Total blood volume (mL) x (patient’s hematocrit - desired hematocrit)] / patient’s hematocrit.
Optimal fluid to use for a neonate with hyper viscosity syndrome from erythrocythemia is normal saline
