Pain responses in preterm infants and parental stress over repeated painful procedures: a randomized pilot trial

In this pilot study, the aims were to determine the feasibility of whether pain behavior in extremely and very preterm infants and perceived parental stress change when parents are involved in pain reducing measures, either actively, performing facilitated tucking or passively, observing the intervention, in comparison to the involvement of nurses only. In addition, the infant's pain reactivity and parental stress over three time points of measurement was of interest.

Extremely and very preterm infants in need of subcutaneous erythropoietin were randomly assigned to the two intervention groups. The intervention encompassed that one parent of each infant was involved during the painful procedure: Either parents executed facilitated tucking themselves or stood by, observing the procedure. Usual care involved that nurse executed facilitated tucking. All infants received 0.5 ml of 30% oral glucose solution via cotton swab before the painful procedure. Infant pain was observed with the Bernese Pain Scale for Neonates (BPSN) and measured with the MedStorm skin conductance algesimeter (SCA) before, during, and after the procedure. Parents' stress levels were measured before and after the painful procedure on the infant, using the Current Strain Short Questionnaire (CSSQ). Feasibility of a subsequent trial was determined by assessing recruitment, measurement and active parental involvement. Quantitative data collection methods (i.e. questionnaires, algesimeter) were employed to determine the number of participants for a larger trial and measurement adequacy. Qualitative data (interviews) was employed to determine parents' perspectives of their involvement.

A total of 13 infants (98% participation rate) were included along with their mothers. Median gestational age was 27 weeks (IQR 26-28 weeks), 62% were female. Two infants (12.5%) dropped out of the study as they were transferred to another hospital. Facilitated tucking turned out to be a good method to actively involve parents in pain reducing measures. No significant differences between the two intervention and control groups were found concerning parental stress and infant pain (p = .927). Power analysis indicated that at least N = 741 infants (power of 81%, α = .05) would be needed to obtain statistically significant results in a larger trial, as effect sizes were smaller than expected. Two of the three measurement tools - i.e. the BPSN and CSSQ) - proved easy to implement and were well accepted. owever, the SCA was challenging in this context. Measurements were also found to be time-consuming and resource-intense (i.e. health professionals as assistants).

Although the intervention was feasible and was readily accepted by parents, the study design was found to be challenging along with the SCA. In preparation of the larger trial, the study design needs to be revisited and adjusted. Thus, issues of time and resources may be resolved. In addition, national and international collaboration with similar neonatal intensive care units (NICU) needs to be considered. Thus, it will be possible to conduct an appropriately powered larger trial, which will yield important results to improve pain management in extremely and preterm infants in NICU.