Oral Sucrose Fails to Reduce Pain in Preterm Infants During Lung Ultrasound

Although lung ultrasound (LUS) is considered non-invasive in nature, handling and probe pressure may provoke pain and transient physiological changes in preterm infants. The aim of this study was to determine whether oral sucrose combined with a pacifier reduces procedural pain and stress in preterm infants undergoing bedside LUS. A two-arm randomized controlled trial was conducted between November 2020 and January 2023. Preterm infants undergoing LUS were randomized to receive either oral sucrose-plus-pacifier or pacifier-alone, administered 2 min before the scan. Pain was evaluated using the premature infant pain profile (PIPP) at four time points: baseline (30 s before intervention), 30 s into scanning, midpoint of the scan, and 30 s post-procedure. Physiological parameters (heart rate, oxygen saturation, and apneic episodes) and duration of the procedure were recorded. Group differences in PIPP scores were analyzed using repeated-measures ANOVA. Out of 60 infants enrolled, 30 infants were randomized in each group with data available on 29 infants in the sucrose-plus-pacifier group and 27 in the pacifier-alone group. Baseline demographics and clinical characteristics were comparable between groups. No statistically significant differences were observed in PIPP scores and physiological parameters at any time point between groups. Repeated-measures ANOVA showed a significant change in PIPP scores across procedural phases (p < 0.0001), with no differences between groups (p = 0.16) or group-by-phase interaction, indicating similar PIPP score trajectories in both groups (p = 0.21). Conclusion: Among preterm infants, sucrose did not add benefit to pacifier-alone for reducing procedural pain and stress during lung ultrasound.Trial registration: NCT05717088. What is Known • Lung ultrasound (LUS) is a bedside, radiation-free imaging modality increasingly used in preterm infants, but probe pressure and handling may still provoke mild procedural discomfort and physiological changes. • Oral sucrose is an established non-pharmacologic analgesic for painful neonatal procedures; however, its benefit during minimally invasive procedures such as LUS remains uncertain. What is New • In this randomized controlled trial, oral sucrose did not provide additional analgesic benefit beyond pacifier use alone during bedside LUS in preterm infants. • These findings suggest that non-nutritive sucking alone may be sufficient for comfort during LUS, supporting its classification as a minimally distressing neonatal bedside procedure.