Electrographic neonatal seizures after infant heart surgery.
OBJECTIVE
Neonatal seizures are relatively common and an important early sign of acute encephalopathy in those who survive infant heart surgery. The contemporary occurrence of seizures in this setting is not fully known, and their electrographic characteristics are incompletely described. This study describes the characteristics of electrographic neonatal seizures (ENSs) in contemporary infants with congenital heart disease (CHD) surgically repaired by using cardiopulmonary bypass, with or without deep hypothermic circulatory arrest.


METHODS
Consecutive infants undergoing heart surgery were monitored by video-EEG for 48 h postoperatively to establish the time of first seizure, total number of ENSs, site(s) of ENS(s) origin and other characteristics.


RESULTS
ENSs occurred in 21 (11.5%) of 183 infants. None had clinically visible seizures. The mean time to the first ENS was 21 h (range, 10-36 h). The total number of ENSs among the entire cohort was 1,429. Mean total number of ENSs per patient over a 48-h period was 72 (range, 1-217). Phenobarbital administration was associated with a > or =50% reduction in seizure counts in five (41.7%) of 12 subjects.


CONCLUSIONS
ENSs were relatively common in a large, contemporary cohort of infants after infant heart surgery. A wide variation was noted in seizure burden, but many experienced numerous seizures. Electrographic neonatal seizures are a candidate outcome end point in future neuroprotection trials in this patient population.
Clancy
Robert R
RR
Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19105, USA. Clancy@email.chop.edu
Sharif
Uzma
U
Ichord
Rebecca
R
Spray
Thomas L
TL
Nicolson
Susan
S
Tabbutt
Sarah
S
Wernovsky
Gil
G
Gaynor
J William
JW
D006348:Cardiac Surgical Procedures; D004569:Electroencephalography / Q000706:statistics & numerical data*; D005260:Female; D006330:Heart Defects, Congenital / Q000601:surgery*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008991:Monitoring, Physiologic / Q000706:statistics & numerical data*; D011183:Postoperative Complications / Q000175:diagnosis*; D012640:Seizures / Q000175:diagnosis*; D014743:Videotape Recording / Q000706:statistics & numerical data