Efficacy and safety of sucrose for procedural pain relief in preterm and term neonates

The purpose of the randomized controlled trial was to determine the most efficacious and safe method of sucrose administration for procedural pain relief in preterm and term neonates. The influence of gestational age on the safety and efficacy of sucrose was explored. The conceptual framework was based on the Gate Control Theory of Pain (Melzack & Wall, 1965; 1996) and an understanding of neonates' capacity to transmit, transduct, perceive and modulate pain impulses in light of their neurological development. A sample of 190 neonates was obtained from one Neonatal Intensive Care Unit (NICU) in Metropolitan Toronto. The primary outcome, pain, was measured by the Premature Infant Pain Profile (PIPP) (Stevens, Johnston, Petryshen & Taddio, 1996). Safety was measured by established criteria for adverse events. Stratification for gestational age was used to control for the effects of age on the primary outcome. Parents of eligible neonates were approached during the first week of life and consent to participate in the study was sought. All neonates whose parents gave consent were randomized, using central randomization, to one of three intervention groups; sucrose and non-nutritive sucking (NNS), sucrose alone or water and NNS. Physiological and behavioral data were collected during the baseline, warming, lance, squeeze and return to baseline phases of a heel lance procedure performed to collect blood for standard diagnostic testing. Demographic data were collected from the medical and nursing records prior to randomization. Data analyses for the primary and exploratory questions were performed utilizing analyses of variance (ANOVA), and post hoc analyses for significant ANOVAs were used to determine where significant differences were found. Due to the small number of adverse events, safety data were reported by frequencies. A hierarchical regression model was used to determine which variables contributed to the variance in pain scores. There were statistically significant differences between intervention groups, with sucrose & NNS being most efficacious. Moreover, the differences in pain responses were significant within each gestational age stratum, with sucrose and NNS most efficacious in all groups. Although the results were statistically significant, further research to determine clinical significant differences in pain scores is required. Few adverse events (n = 6) occurred during the study period and none of the events occurred in the sucrose and NNS group. The most immature preterm neonates experienced the greatest number of adverse events compared to their older preterm and term counterparts. Intervention group and gender contributed to the most variance in pain scores. PIPP scores were significantly lower in the most immature gestational age stratum (27-31 6/7 weeks) compared to older preterm (32-35 6/7 weeks) and most mature (>=36 weeks) neonates. Sucrose and NNS are readily available in NICUs and easily incorporated into standard nursing care. The challenge will be to have nurses incorporate these research findings into practice. Since neonatal pain assessment and management is an ongoing requirement in the NICU, continuous evaluation of the best available practices is required. Therefore, future research examining the efficacy and safety of repeated doses of sucrose & NNS (with or without other interventions) for a variety of painful procedures and diseases is required.