Neonatal Hematology: Blood Disorders, Blood
Volume, and Rh Incompatibility Questions with
100% Correct Answers
What does polycythemia mean?
An increased total red blood cell mass.
What is hyperviscosity?
Blood that is thicker than normal, usually due to too many red blood cells.
What central venous hematocrit level defines polycythemia of the newborn?
Central venous hematocrit >65%.
How is hyperviscosity defined in terms of blood viscosity?
Blood viscosity >14 centipoises.
What is the main factor affecting neonatal blood viscosity?
Hematocrit.
What percentage of newborns are affected by polycythemia?
1-4%.
What percentage of normal newborns experience hyperviscosity without polycythemia?
About 1%.
What can cause hypoglycemia in polycythemic infants?
Reduced plasma volume due to increased red blood cell mass.
What percentage of polycythemic infants may experience hypoglycemia?
, 12-40%.
What factors can contribute to hyperviscosity?
Hematocrit, plasma viscosity, red blood cell aggregation, and red blood cell membrane
deformability.
How does altitude affect polycythemia?
High altitude causes a physiological increase in RBC mass due to lower oxygen availability.
When does hematocrit typically peak in newborns?
At 2-4 hours of life.
What obstetric factor can increase hematocrit in newborns?
Delayed cord clamping or cord milking.
What is the incidence of polycythemia in infants of diabetic mothers?
Polycythemia incidence >40%.
What is twin-twin transfusion syndrome?
A condition in monochorionic twin pregnancies where one twin becomes polycythemic and
the other anemic.
What are common clinical symptoms of polycythemia and hyperviscosity?
Lethargy, irritability, respiratory distress, and feeding intolerance.
What is a rare finding in the central nervous system for polycythemic infants?
Seizures.
What is the significance of delayed cord clamping?
Volume, and Rh Incompatibility Questions with
100% Correct Answers
What does polycythemia mean?
An increased total red blood cell mass.
What is hyperviscosity?
Blood that is thicker than normal, usually due to too many red blood cells.
What central venous hematocrit level defines polycythemia of the newborn?
Central venous hematocrit >65%.
How is hyperviscosity defined in terms of blood viscosity?
Blood viscosity >14 centipoises.
What is the main factor affecting neonatal blood viscosity?
Hematocrit.
What percentage of newborns are affected by polycythemia?
1-4%.
What percentage of normal newborns experience hyperviscosity without polycythemia?
About 1%.
What can cause hypoglycemia in polycythemic infants?
Reduced plasma volume due to increased red blood cell mass.
What percentage of polycythemic infants may experience hypoglycemia?
, 12-40%.
What factors can contribute to hyperviscosity?
Hematocrit, plasma viscosity, red blood cell aggregation, and red blood cell membrane
deformability.
How does altitude affect polycythemia?
High altitude causes a physiological increase in RBC mass due to lower oxygen availability.
When does hematocrit typically peak in newborns?
At 2-4 hours of life.
What obstetric factor can increase hematocrit in newborns?
Delayed cord clamping or cord milking.
What is the incidence of polycythemia in infants of diabetic mothers?
Polycythemia incidence >40%.
What is twin-twin transfusion syndrome?
A condition in monochorionic twin pregnancies where one twin becomes polycythemic and
the other anemic.
What are common clinical symptoms of polycythemia and hyperviscosity?
Lethargy, irritability, respiratory distress, and feeding intolerance.
What is a rare finding in the central nervous system for polycythemic infants?
Seizures.
What is the significance of delayed cord clamping?
