Sensorial saturation in neonatal and infant pain management compared to other non-pharmacological and pharmacological analgesic techniques: a systematic review

Background: Sensorial saturation (SS) is a non-pharmacological approach for the management of pain in newborns during medical procedures. Despite its growing adoption, the comparative effectiveness of SS versus other analgesic interventions remains under investigation. This review aims to verify the validity of this method, compared to other analgesic approaches.

Methods: We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines to conduct a systematic search in MEDLINE and Scopus databases from January 2017 to June 2025. Inclusion criteria: randomized controlled trials that examined the effects of SS in term and preterm neonates undergoing painful medical procedures. Exclusion criteria: reviews, case reports, and commentaries; studies on animals; articles focusing on non-pain-related interventions (e.g., neuromuscular diseases or dementia); studies conducted in adult populations; and studies on children older than 1 year of age. Data were retrieved following a standardized protocol, and risk of bias was assessed using the Cochrane Risk of Bias Tool.

Results: A total of 7 studies met the inclusion criteria. The total number of patients is 700, including 246 preterm newborns (115 male, 83 female and 48 newborns of unspecified sex; average weight 1,500–2,300 grams; age 4–30 days), 283 term newborns (158 male and 125 female; average weight 3,100–3,200 grams; age 2–23 days), and 171 newborns (79 male and 92 female) aged 4–6 months (6,700 grams and 7,500 grams, respectively). These included two studies using heel prick as a painful stimulus, one study eye examination, two studies used venipuncture, one bathing and one pentavalent vaccination. All studies have shown that SS is a safe practice and has a superior analgesic efficacy compared to other non-pharmacological interventions, including sucrose administration alone, breastfeeding alone, and swaddling alone. These findings highlight SS as a consistent and effective pain management strategy.

Conclusions: This review confirms the effectiveness of SS in neonatal pain management and expands its applicability to infants. However, the nature of non-pharmacological interventions precludes blinding. Minor limitations across the included studies include the lack of physiological data (e.g., blood cortisol), small sample sizes, and potential confounding factors such as the use of oral sucrose or prior feeding. However, SS remains a safe and cost-effective primary intervention. Further high-quality trials are recommended to consolidate these findings and explore its broader applications.