Effects of Handling and Environment on Preterm Newborns Sleeping in Incubators

Abstract

Objective: To describe the total sleep time, stages of sleep, and wakefulness of preterm newborns and correlate them to levels of sound pressure, light, temperature, relative air humidity, and handling inside incubators. Design: Observational, correlational study. Setting: A neonatal intermediate care unit. Participants: Twelve preterm newborns, who were 32.2 +/- 4.2 weeks gestational age and weighed 1,606 +/- 317 g. Methods: Sleep records were assessed by polysomnograph. Environmental variables were measured with a noise dosimeter, light meter, and thermohygrometer. To record time and frequency of handling, a video camera was used. All recordings were made for an uninterrupted 24-hour period. Results: Mean total sleep time in 24 hours was 899 +/- 71.8 minutes (daytime = 446 +/- 45.3 and nighttime = 448 +/- 60.2). Mean wakefulness was 552 +/- 94.0 minutes. The predominant stage was quiet sleep. A significant correlation was identified only between the levels of light and wakefulness (r = 0.65 and p = .041). Conclusion: The environmental conditions and care provided to hospitalized preterm newborns did not influence sleep except for high light levels, which increased wakefulness. Nurses in clinical practice should implement strategies to promote and protect sleep by decreasing newborns' exposure to excessive light.