Forty very low birth weight (VLBW) infants with non-oliguric
hyperkalemia in the first few days after birth were enrolled in this study. They were randomly divided into 2 groups,
regular insulin (RI) infusion group and
kayexalate resin
enema group.
Therapy was administered when serum
potassium level was greater than 6 mEq/L. None of these infants received
blood transfusion during this study course. In RI group (n = 20), the ratio of infusion
glucose to
regular insulin was 10-15 gm
glucose to 1 unit RI, and the
glucose infusion rate was maintained at least 6 mg/Kg/min. In
Kayexalate group (n = 20), the dose of
Kayexalate was 1 gm/Kg
body weight given rectally every four hours. All treatment discontinued after the serum
potassium level returned to normal for 6 hours. The mean gestational ages were 27.4 +/- 1.8 weeks in RI group and 28.4 +/- 2.4 weeks in
Kayexalate group, respectively. Mean
birth weights were 935 +/- 259 gm (RI) and 1065 +/- 214 gm (
Kayexalate). The ages at onset of
hyperkalemia were 24.6 +/- 8.2 (RI) and 22.2 +/- 8.1 (
Kayexalate) hours after birth. The mean urine outputs during the 8-hour interval prior to development of
hyperkalemia were 5.4 +/- 1.3 (RI) and 5.5 +/- 0.9 (
Kayexalate) ml/kg/min. The durations of
hyperkalemia were 26.4 +/- 14.9 (RI) and 38.6 +/- 13.3 (
Kayexalate) hours. The peak serum
potassium levels during
therapy were 7.3 +/- 0.9 and 7.4 +/- 0.6 mEq/L. The incidences of grade II and above intraventricular
hemorrhage (IVH) were 15% (3/20) and 50% (10/20). The incidences of
cardiac dysrhythmia were 5% (1/20) and 10% (2/20). Significantly shorter duration of non-oliguric
hyperkalemia and lower incidence of IVH were noted in RI group, but there were no differences in the peak
potassium level or the incidence of
cardiac dysrhythmia between these two groups. We conclude that to use early continuous
regular insulin infusion
therapy for the treatment of non-oliguric
hyperkalemia in VLBW infants is more effective than
kayexalate in decreasing the duration of
hyperkalemia and reducing the incidence of intraventricular
hemorrhage.