Abstracts

To quantify the movement in each different sleep-phases in full-term newborns and comparing with number of the phases. We analyzed the amount of movement, according to a proposed Motor Index (MI) of 32 polissonographic studies of normal full-term newborn babies born at the Hospital de Cl[iacute]nicas da UFPR. MI was dubbed (MI 3) when there were findings suggestive of movement in more than 50% of an EEG epoch, (MI 1) when no movements could be observed and Average MI 2 when findings of movement where observed in less than 50% of an EEG epoch. Movement features were obtained through annotations on the exam such as movement of feet, hands, head, mouth, suction movements and generalized movements, among others. An additional electromyographic channel aided in registering an increase in amplitude or irregularity of registry, when the EEG was obscured by muscular and/or movement artifacts. All of these variables were quantified in each different sleep-wake phase. The mean duration of registry was of 57.45 minutes and the total amount was of 1838.4 minutes. The mean duration of M 3 was of 18.33 minutes, M 2 of 16.36 and of M 1 of 21.5 minutes. During quiet sleep the mean duration of M 3 was of 22.3 minutes and during active sleep 323 minutes. Mean duration of M 1 in quiet sleep was of 446.33 and in active sleep was of 171.6. In quiet sleep the mean duration of M 2 was of 134.33, 240 during active sleep, 84.6 minutes in transitional sleep, and 67.6 minutes in the wake state. The sum of M 3 and M 2 was of 563 minutes (30.6% of the total time). Considering the incidence of each sleep phase, quiet sleep occurred at a rate of 3.1/exam (range 1 - 8/exam), active sleep 3.3/exam (raging 1 - 9/exam), transitional sleep 3.9/exam (range 0-9/exam) and awake 3.9/exam (range 0-10/min). When the number of phases is compared with de movements, the instable sleep there are more movements. The statistical test used was regression multiple, with co-variance time of the electroencephalogram. In all our exams the newborns remained the majority of time in sleep. Movements are observed in a greater amount during active sleep, predominantly in those patients who had a greater variation of sleep phases. There are more movements in instable sleep neonates.
In the visual analysis of neonatal EEG one must classify the different phase of the sleep-wake cycle based on polygraphic features and their changes according to each phase. In addition, quantifying the amount of each sleep phase may be of help in determining whether the polissonographic findings are those of a normal newborn or of an abnormal one.