[Middle latency auditory evoked potentials in critical care children: preliminary study].
BACKGROUND
Middle latency auditory evoked potentials (MLAEP) reflect changes in electroencephalogram waves after an auditory signal and represent the earliest cortical response to acoustic stimulus. They are therefore used to measure variations in the level of consciousness. MLEAP have been used to measure the depth of anesthesia during surgical procedures, but experience in critical care patients is very limited.


OBJECTIVE
To analyze the utility of MLAEP for monitoring the level of sedation in critically ill children.


METHODS
Level of consciousness was monitored through MLAEP by placing special headphones and three sensors situated in the frontal and preauricular regions. Simultaneously, the level of sedation was measured using the COMFORT scale and the Bispectral Index (BIS) in distinct clinical situations.


RESULTS
We studied six critically ill children in whom MLAEP helped us to evaluate the level of consciousness: light sedation, natural sleep, deep sedation, sedation in a paralyzed child, and brain death. MLAEP showed a good correlation with the COMFORT scale and BIS in light and deep sedation and were effective in the early detection of brain death in one patient. In the paralyzed patient, MLAEP was able to detect undersedation. In one patient, a pacemaker interfered with the MLAEP signal.


CONCLUSIONS
MLAEP can be useful in evaluating the level of consciousness and sedation in critically ill children. Further studies with larger samples are required to analyze the limitations and reproducibility of this type of monitoring in children of different ages.
Lamas Ferreiro
A
A
Sección de cuidados Intensivos Pediátricos, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
López-Herce
J
J
Sánchez Pérez
L
L
Mencía Bartolomé
S
S
Borrego Domínguez
R
R
Carrillo Alvarez
A
A
D001926:Brain Death / Q000175:diagnosis*; D002648:Child; D003422:Critical Care; D016638:Critical Illness; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D014474:Unconsciousness / Q000175:diagnosis*