The effect of breast milk and other odor interventions applied during venous procedures in the neonatal intensive care unit on the pain and comfort level of premature neonate: Systematic review and meta-analysis

Abstract

Purpose

This systematic review and meta-analysis was conducted to determine the effect of breast milk and other scent interventions applied during venous procedures in the Neonatal Intensive Care Unit on premature babies’ pain and comfort levels.

Materials and methods

This review [PROSPERO:CRD42024547970] searched eight (8) databases (Cochrane, PubMed, EBSCO, ScienceDirect, Web of Science, Scopus, TR Index, CINAHL). A search strategy specific to each database was created by using the keywords of published studies on the subject. In general, the words ((Comfort OR Pain) AND (Preterm) AND (“neonatal intensive care unit” OR NICU) AND (venipuncture OR bloodletting OR catheter OR cannula)) were used. Population, Intervention, Comparison, Outcome(s) of interest, and Study design (PICOS framework) and studies published between 2014 and 2024 that met the inclusion criteria have been examined by researchers between the dates May 01, 2024 and July 01, 2024. Data were analyzed using Comprehensive Meta-Analysis (CMA). For comparison of binary data, odds ratio (OR) (95% CI) was calculated. For continuous data, mean difference (MD) with a 95% confidence interval was estimated. OR was used to calculate the joint effect. A value of p < 0.05 was considered statistically significant.

Results

As a result of the searches made with the search strategy, a total of 214 studies were reached. Of these studies, 17 were removed as a result of duplication and 188 were removed as a result of title and abstract reviews. The full texts of the remaining nine studies were examined and two studies that did not meet the inclusion criteria were excluded. Among these, one study was eliminated because the comparison was not appropriate because each infant had its own control, and one study was eliminated because the results were not appropriate. A total of seven researchers were found to meet the involvement criteria and were included in this meta-analysis study. It was found that breast milk and other odors interventions had a large effect on reducing the pain scores of premature babies, and the effect size of all studies except one study included in the meta-analysis was statistically significant. Subgroup analysis according to odor types revealed that breast milk odor and other odors were effective interventions in reducing pain reactivity. There was not enough evidence to state that odor interventions had a positive effect on the comfort levels of newborns.

Conclusion

There is a need for studies with a high level of evidence examining the effects of odor interventions on the comfort level of premature babies.