Short-term effects of incubator covers on quiet sleep in stable premature infants

Incubator covers are increasingly being used in neonatal care as part of mi nimal disturbance strategies. The aim of this study was to examine possible effects of incubator covers on sleep patterns in stable premature infants. Quiet sleep (QS) can be investigated by amplitude-integrated electroenceph alography (aEEG) at 32-34 wk gestational age. In nine premature infants (ge stational ages 26-32 wk, median 29) QS periods were measured at a postconce ptional age of 32-34 wk (median 34) during two consecutive 24 h periods, on e period with a padded dark cover over the incubator and one period without the cover, in a randomized order. There were no significant differences be tween the two 24 h periods (with incubator cover and without cover, respect ively) regarding the duration of the QS periods, the percentage of QS of th e total recording time (%QS) or the duration of QS intervals. However, ther e was a positive correlation between postnatal age in days and the mean dur ation of QS periods when incubator covers were used (r = 0.90, p = 0.001). When the covers were used there was a difference between the girls and the boys in the duration of QS intervals (p = 0.032); the QS intervals increase d in the live girls from median (range) 63.2 (49.4-94.6) min to 77.2 (59.3- 100.9) min (p = 0.043). There was no difference in the duration of QS perio ds between girls and boys. Conclusion: Incubator covers seem to have some short-term effects on Sleep quality in premature infants but the clinical significance and possible lon g-term effects are not known.