Circulatory failure due to severe cardiac arrhythmia as a result of hyperkalemia in a very low birth weight infant

BACKGROUND: Hyperkalemia is frequently seen during the first days of life in premature infants with a gestational age at birth less than 28 weeks. Normally, these high concentrations of potassium are well tolerated of the premature infants. In a few cases hyperkalemia leads to life-threatening cardiac arrhythmias. CASE REPORT: We report about a 800 grams weighing preterm infant born after 26 + 4 gestational weeks. 24 hours after birth the infant developed 2 : 1 atrioventricular block due to hyperkalemia with a heart rate about 75 bpm. The bradycardia continued about 45 minutes in spite of immediate therapy concomitant by circulatory failure that resulted in an intraventricular hemorrhage of grade III with periventricular intraparenchymal lesions. CONCLUSIONS: The case report demonstrates the variations of the electrocardiogram that can be found in preterm infants with hyperkalemia and their potential risks. Therapy of symptomatic hyperkalemia is not able to interrupt early a life-threatening circulatory failure in any case.