NEONATAL POLYCYTHEMIA MEDICAL CARE

Medical Care:
Therapy is based on both the measured central venous Hct and the presence or absence of symptoms. Treatment of polycythemia with partial exchange transfusion remains controversial. Regarding treatment with partial exchange, the Committee of the Fetus and Newborn of the American Academy of Pediatrics states, "The accepted treatment of polycythemia is partial exchange transfusion (PET). However there is no evidence that exchange transfusion affects the long term outcome."

• Treatment for asymptomatic patients
o Hct 65-75%: Liberally give fluids, perform cardiorespiratory monitoring and monitoring of Hct and glucose levels every 6 hours, and observe the patient for symptoms.
o Hct >75% on repeated measurements: Consider partial exchange transfusion.
o If the etiology is dehydration: Rehydrate the patient over 6-8 hours.

• Treatment for symptomatic patients
o Hct 60-65%: Consider alternative explanations for the symptoms. Although hyperviscosity may be the etiology of the symptoms, other causes for the symptoms must be excluded.
o Hct >65% with symptoms attributable to hyperviscosity: Perform partial exchange transfusion.

• Partial exchange transfusion
o Perform a partial exchange transfusion by using an umbilical arterial or venous catheter to reduce the central Hct to 50-55%.
o The total blood volume to be exchanged is determined as follows: [blood volume (patient's Hct – desired Hct)]/(patient's Hct), where blood volume = the patient's weight in kilograms multiplied by 90 mL/kg.
o Normal saline is the replacement fluid of choice for exchange transfusions because it is effective and inexpensive. As alternatives, Plasmanate, 5% albumin, or fresh frozen plasma can be used. However, none of these is more effective than normal saline. In addition, both 5% albumin and fresh frozen plasma are blood products, and certain religious beliefs prohibit their use.
o Sterile technique is required.
o An exchange transfusion can be performed in 3 ways, depending on the type of vascular access that is available. Regardless of the method used, aliquots should not exceed approximately 5 mL/kg delivered or removed over 2-3 minutes.
- If only a single umbilical arterial or venous catheter is in place, use a push-pull technique. With this technique, the withdrawal of blood is alternated with the administration of replacement fluid through the single catheter. Do not remove more than 5% of the patient's calculated blood volume in any single withdrawal.
- If both umbilical venous and arterial catheters are in place, withdraw blood from the arterial catheter while administering the replacement fluid through the venous catheter
- If a venous or arterial umbilical catheter and a peripheral venous catheter are in place, the former can be used for blood withdrawal, while the latter is used to simultaneously and continuously infuse the replacement fluid.

Further Inpatient Care:
• Carefully monitor vital signs and bilirubin, glucose, and electrolyte levels as needed
• Feedings may cautiously be introduced a number of hours after completing the partial exchange transfusion.

Further Outpatient Care:
• Perform routine newborn follow-up care.

Complications:
• Apnea
• Arrhythmia
• Vasospasm
• Vessel perforation
• Air embolus
• Thrombosis
• Infarction
• Thrombocytopenia
• Hemolysis
• Electrolyte abnormalitie
• Hypoglycemia
• Hypocalcemia
• Intrahepatic hematoma
• Necrotizing enterocolitis

Prognosis:
• Infants are at increased risk for neurological deficits including speech abnormalities, fine-motor delays, and gross-motor delays.

• Partial exchange transfusion has not been shown to reduce these problems.

Medical/Legal Pitfalls:
• Use of a blood product (eg, albumin) in an exchange transfusion may result in the transmission of infection. Infections related to blood products can be avoided by using normal saline, which is sterile and which has been shown to be as effective as albumin.

• Informed consent must be obtained as exchange transfusions have multiple risks.

• The question regarding the efficacy of partial exchange transfusion in improving neurologic outcomes has not been answered. However, polycythemia and neurologic abnormalities have been linked. With this in mind, a symptomatic infant who has not been treated with partial exchange transfusion and who subsequently develops neurologic abnormalities may be considered inadequately treated.