Background: Determining the effectiveness of pain management strategies in newborns provide evidence to promote high-quality midwifery practices.

Purpose: The aim of the research is to evaluate the effect of the nesting technique on pain response during heel prick blood sampling in newborns.

Method: During the heel prick blood collection procedure at a university hospital, pain responses were evaluated in 29 full-term newborns who were held in a nest made of specially designed pillows for 3 minutes before, during, and after the procedure, and in 30 full-term newborns who underwent the routine procedure without being placed in a nest. Data were collected using the Baby Information Form, Observation Form, and the Neonatal Infant Pain Scale. A statistical software package was used for data analysis. As the data were normally distributed, the Independent t-test was used to compare group means, and Repeated Measures ANOVA was employed to assess differences over time.

This study is a randomized controlled experimental trial designed to evaluate the effect of the nesting technique on behavioral and physiological outcomes - specifically pain scores, crying duration, respiratory rate, heart rate, and SpO₂ - measured at three time points: baseline (before the procedure), during the procedure, and during recovery (after the procedure).

Hypotheses H₀: The nesting technique has no significant effect on newborns' pain, crying duration, heart rate, oxygen saturation, or respiratory rate during heel prick blood sampling.

H₁: The nesting technique has significant effect on newborns' pain, crying duration, heart rate, oxygen saturation, or respiratory rate during heel prick blood sampling.

Sample Inclusion criteria for the study included term newborns undergoing routine heel prick blood sampling, with a birth weight between 2500 g and 4000 g, not receiving any medications, and whose parents provided consent for participation. The sample size was determined through a power analysis based on the Neonatal Infant Pain Scale (NIPS) score averages at the third measurement time point. The effect size, calculated as Cohen's d = 0.83, was derived from the difference between the intervention (2.06 ± 2.83) and control (4.44 ± 2.93) groups. For two independent groups, with a 95% confidence level (α = 0.05) and 80% statistical power (1-β = 0.80), it was determined that each group required at least 25 newborns. The study was completed with a total of 59 newborns, comprising 29 in the intervention group and 30 in the control group.

Intervention The study was conducted at a university hospital between May and August, 2024. Detailed information about the study was provided to the parents of eligible newborns, and written and verbal informed consent was obtained. Newborns were randomized by an independent researcher not involved in the intervention, using an online random list generator, namely, Random.org website, to ensure randomization. The randomization list was provided to the researchers performing the interventions in sealed envelopes to prevent bias during the study process. The study was conducted as a single-blind trial in which the researcher performing data analysis was blinded to group allocation; the clinical staff implementing the procedures could not be blinded due to the visible nature of the intervention.

In the intervention group, the nesting technique was applied prior to the heel prick procedure. The nesting technique involved positioning the newborn in a lateral position with hands and legs flexed, without restricting movement, using specially prepared support materials (cotton-filled pillows) to create a nest that contacted all body surfaces. The newborn was kept in the nest for 3 minutes. Physiological parameters and the NIPS were assessed at the end of the 3-minute period. The heel prick procedure, performed by the clinical midwife, was followed by assessments of physiological parameters and NIPS during the procedure. After the procedure, the nesting technique was applied for an additional 3 minutes, and physiological parameters and NIPS were evaluated at the end of this period.

In the control group, newborns were kept in their natural position on the bed for 3 minutes before the heel prick procedure, with physiological parameters and NIPS assessed at the end of this period. The heel prick procedure, performed by the clinical midwife, was followed by assessments of physiological parameters and NIPS during the procedure. After the procedure, newborns were kept in their natural position for 3 minutes, and physiological parameters and NIPS were evaluated at the end of this period (Figure 1) Data Collection Data were collected using the "Infant Information Form," a 5-parameter "Observation Form" for assessing physiological changes, and the NIPS.

Procedural Standardization Heel lances were performed 30-45 minutes after feeding while infants were awake or in light sleep. Procedures were done solely for postnatal screening and not combined with other caregiving activities to avoid confounding stimuli.

Data Analysis IBM SPSS Statistics version 29.0 was used for all analyses. Descriptive statistics, including frequency, percentage, mean, and standard deviation, were calculated. The dataset was subjected to preliminary analyses to test assumptions of normality and homogeneity of variance. Normality was assessed using the Kolmogorov-Smirnov test. As the data followed a normal distribution, parametric tests were used. The Independent Samples t-test was employed to compare means between groups. Repeated Measures Analysis of Variance (ANOVA) was used to evaluate significant differences in measurements over time. A significance level of p ≤ 0.05 was adopted for all analyses.

Inclusion Criteria:

• Term newborns undergoing routine heel prick blood
• Weight between 2500 g and 4000 g,
• Not receiving any medications, and Whose parents provided consent for participation.

Exclusion Criteria:

• Newborns with any medical condition that could affect physiological or behavioral responses,
• Infants who were clinically unstable or receiving medication