Comparing the Effects of Continuous and Cyclical Lightings on Weight Gain and Length of Hospital Stay Among Preterm Neonates

Background: Hospitalization in neonatal intensive care units predisposes preterm neonates to negative stimuli such as continuous 24-hour lighting. Objectives: The present study was done to evaluate the effects of a cyclical lighting model on weight gain and length of hospital stay among preterm neonates. Methods: This clinical trial was performed during year 2012 on 60 preterm neonates, who were hospitalized in the neonatal intensive care unit of Bentolhoda hospital, Bojnord, Iran. The neonates were conveniently recruited and randomly allocated to a control and an experimental group through permuted block randomization. The neonates in these groups were exposed to continuous and cyclical lighting, respectively. Their weight and sleeping time were measured both before and after the intervention. Moreover, the length of their hospital stay was documented. The data were analyzed through doing the independent-sample t and the Mann-Whitney U tests by using the SPSS software (v. 18.0) at a significance level of less than 0.05. Results: Before the study intervention, the groups did not differ significantly regarding the neonates' birth weight, Apgar score, height and sleeping time (P > 0.05). Compared with baseline values, the neonates' weight in the control and the experimental groups increased significantly during the study by 263±52 and 232±48 grams, respectively (P = 0.02). Moreover, the means of hospital stay in the groups were 10.6 ± 1.5 and 9.1 ± 1.4 days (P=0.03) while the means of sleeping time were 17.03±2 and 18.3 ± 2 hours/day (P = 0.02), respectively. Conclusions: Using cyclical lighting in the same way as usual day/night-based lighting is recommended for neonates, who are hospitalized at neonatal intensive care units.