title: Electroencephalographic activity in response to procedural pain in preterm infants born at 28 and 33 weeks gestational age.
abstract: OBJECTIVE
  Preterm infants undergo frequent painful procedures in the neonatal intensive care unit. Electroencephalography (EEG) changes in reaction to invasive procedures have been reported in preterm and full-term neonates. Frontal EEG asymmetry as an index of emotion during tactile stimulation shows inconsistent findings in full-term infants, and has not been examined in the context of pain in preterm infants. Our aim was to examine whether heel lance for blood collection induces changes in right-left frontal asymmetry, suggesting negative emotional response, in preterm neonates at different gestational age (GA) at birth and different duration of stay in the neonatal intensive care unit.
  
  
  METHODS
  Three groups of preterm infants were compared: set 1: group 1 (n=24), born and tested at 28 weeks GA; group 2 (n=22), born at 28 weeks GA and tested at 33 weeks; set 2: group 3 (n=25), born and tested at 33 weeks GA. EEG power was calculated for 30-second artifact-free periods, in standard frequency bandwidths, in 3 phases (baseline, up to 5 min after heel lance, 10 min after heel lance).
  
  
  RESULTS
  No significant differences were found in right-left frontal asymmetry, or in ipsilateral or contralateral somatosensory response, across phases. In contrast, the Behavioral Indicators of Infant Pain scores changed across phase (P<0.0001). Infants in group 1 showed lower Behavioral Indicators of Infant Pain scores (P=0.039).
  
  
  CONCLUSIONS
  There are technical challenges in recording EEG during procedures, as pain induces motor movements. More research is needed to determine the most sensitive approach to measure EEG signals within the context of pain in infancy.
authors: *Faculty of Health Sciences §Epidemiology Department, Ben Gurion University of the Negev ∥Soroka Medical Center, Beer Sheva, Israel †Pediatrics Department, University of British Columbia ‡Developmental Neurosciences and Child Health, Child and Family Research Institute, Vancouver, BC, Canada ¶Orgil Medical Instruments, Or Akiva, Israel.
authors: Neta
authors: N
authors: Maimon
authors: Ruth E
authors: RE
authors: Grunau
authors: Ivan L
authors: IL
authors: Cepeda
authors: Michael
authors: M
authors: Friger
authors: Leonel
authors: L
authors: Selnovik
authors: Shlomo
authors: S
authors: Gilat
authors: Eilon
authors: E
authors: Shany
mesh_terms: D002540:Cerebral Cortex / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D007363:Intensive Care Units, Neonatal; D008297:Male; D010146:Pain / Q000503:physiopathology*; D010147:Pain Measurement; D011446:Prospective Studies