Neonatal hyperviscosity: randomized study of effect of partial plasma exchange transfusion on long-term outcome.

The use of partial plasma exchange transfusion in newborns with polycythemia and hyperviscosity was evaluated. Ninety-three infants with polycythemia and hyperviscosity were randomly assigned to receive either partial plasma exchange transfusion or symptomatic treatment; the infants were matched with control infants without polycythemia. Neonatal course and outcome at 1 and 2 years were evaluated for each of the three groups. Polycythemic infants had more fine motor and speech problems at 1 year of age than did control infants. At 2 years of age, polycythemic infants had more gross motor delays, neurologic diagnoses, fine motor abnormalities, and speech delays than did the control infants. There was no significant difference at 1 year between the polycythemic infants who had received partial plasma exchange transfusion and those given only symptomatic care. At 2 years, the group receiving partial plasma exchange transfusion had fewer neurologic diagnoses and fine motor abnormalities.

Gastrointestinal injury in polycythemic term infants.

Necrotizing enterocolitis is uncommon among term infants. In this group, necrotizing enterocolitis has been associated with two risk factors: polycythemia and umbilical catheterization. During a randomized trial of partial plasma exchange transfusion for treatment of polycythemia, an increased risk of gastrointestinal problems was noted. Eight hyperviscous patients treated with partial plasma exchange transfusion, no symptomatically treated patients, and no control infants developed typical necrotizing enterocolitis (blood in the stools, pneumatosis, and systemic signs). The incidence of necrotizing enterocolitis was significantly greater among patients treated with exchange transfusion compared with patients treated symptomatically or control subjects (P less than .001).

Developmental and neurologic sequelae of neonatal hyperviscosity syndrome.

One hundred eleven consecutive infants with neonatal hyperviscosity were identified by screening all newborns for polycythemia in an 18-month period. These polycythemic infants were matched with non-polycythemic newborns for birth weight, gestational age, Apgar scores, and sex. Maternal, intrapartum, and neonatal data were analyzed for associated morbidity. Maternal preeclampsia was more common among the hyperviscous patients than among control subjects. Hypoglycemia was also significantly increased among the hyperviscous patients. Follow-up studies at 1 to 3 years of age revealed a significantly higher incidence (38% vs 11%) of motor and neurologic abnormalities in the infants with neonatal hyperviscosity. The data suggested that concurrent hypoglycemia increased the risk of a poor outcome in hyperviscous infants inasmuch as 55% of infants with both characteristics were abnormal at follow-up. This, however, was not significantly different from the outcome of infants with hyperviscosity alone (P greater than .05 but less than .1). Further studies will be needed to confirm or deny this relationship.