Effects of a flexed posture in the prone position with boundaries following endotracheal suction in very low birthweight infants

Abstract

Aim: The purpose of this study is to determine the differences in behavioral responses (signs of stress and sleep-wake state) following endotracheal suction in very low birthweight infants between routine care and flexed posture with boundaries. The nine infants in this study had a mean gestational age of 26.96 weeks (ranging from 23 weeks and 6 days to 28 weeks and 6 days) and a mean birthweight of 968.4 g (ranging from 572 to 1524 g).Methods: Heart rate and arterial oxygen saturation were monitored to assess autonomic functions, while motor system parameters were assessed visually through observation. Autonomic and motor system variables were combined and used to trace signs of stress. States of sleep were assessed according to the Thoman classification system. Observations were made every 2 min for 30 min, commencing at baseline and finishing 30 min after the end of suctioning.Results: A total of 42 sessions were recorded, comprising 20 for the experimental group and 22 for the control group. The two groups did not differ significantly in birthweight and gestational age at birth. The results of a two-way repeated measures (ANOVA) for each variable indicated that the groups differed significantly in signs of stress. There were significant differences in the effects of time (F = 3.530, P = 0.0001), intervention (F = 12.476, P = 0.001), and intervention-by-time interaction for signs of stress (F = 3.018, P = 0.001). The experimental group exhibited fewer signs of stress than the control group. The time before onset of a quiet sleep state differed significantly between the groups (t = -2.529, d.f. = 35, P = 0.016); the time for the experimental group was significantly shorter than for the control group.Conclusion: The flexed posture in the prone position with boundaries around the infant's body is needed to enhance self-regulatory behavior in very low birthweight infants and to help them maintain behavioral integrity.