Electrocortical Activity at 7 Days of Life is Affected in Extremely Premature Infants with Patent Ductus Arteriosus

Background: The aim of this study was to determine whether the aEEG at 7 days of life is influenced by the presence of a PDA in non-sedated extremely low gestational age preterm infants.

Patients: We prospectively recruited infants born at less than 28 weeks of gestation between 11/2007 and 12/2009.

Method: aEEGs were recorded at seven days of life and assessed by using the Burdjalov score and the electronically assessed lower border (eLBA). Kruskal-Wallis-Test and linear regression analysis were performed to determine how GA and a PDA affect the aEEG score and the eLBA. Using linear regression analysis we tested which components of the score are affected by a PDA.

Results: We recruited 44 infants with a GA of 26.5/7 (23.4/7-27.6/7) weeks and a birth weight of 837 (461-1230) g. The total sum of score points increased from 4 (1-6) to 8 (5-9) points in infants born at 23/24 weeks and 27 weeks of gestation, respectively. In infants with relevant PDA the aEEG scored lower with 8 (3-10) points compared to those with PDA: 5 (1-8) points. Linear regression analysis showed a positive influence of GA and a negative influence of a PDA on the total score. GA had a positive influence on SWC and the visually assessed LBA. A PDA had a negative influence on continuity. The eLBA increased from 4.61 (3.18-5.53) µV to 5.27 (3.38-6.51) µV in infants of 23/24 vs. 27 gestational weeks, but was not significantly influenced by a PDA.

Conclusion: A PDA has a negative influence on the total Burdjalov score and continuity at 7 days of age in infants born at less than 28 weeks of gestation. The electrocortical disturbances may be the consequence of a diminished cerebral perfusion in the presence of a PDA.