Analgesic effect of non-nutritive sucking in term neonates: A randomized controlled trial

Newborns commonly experience pain due to a variety of reasons. Non-nutritive sucking (NNS) is thought to be an effective non-pharmacological method of pain-relief. However, the significant heterogeneity in some systematic reviews limited the certainty of the findings about NNS. Hence, this study was aimed at evaluating the analgesic effect and safety of NNS in healthy term neonates during the heel prick test, using the Neonatal Pain Agitation and Sedation Scale (N-PASS).

In this randomized controlled trial, 42 term infants were included: 22 infants in the intervention group (receiving NNS) and 20 infants in the control group (not receiving NNS). In the intervention group, neonates were given a silicone pacifier 120 s before, during, and 120 s after the heel puncture, while neonates in the control group received routine care. Pain-related outcomes were assessed using the N-PASS at 30s, 60s, 90s, and 120s after the heel prick. Any adverse events during the procedure were noted. The Spearman correlation coefficients between the pain scores on the N-PASS and two other scales (NFCS and NIPS) were calculated at all four moments of evaluation.

The mean N-PASS pain scores at 30s, 60s, 90s, and 120s after heel prick were significantly lower in the NNS group than in the control group: 4.73 ± 2.78 vs. 7.90 ± 1.52 (p = 0.0002); 3.64 ± 3.06 vs. 5.55 ± 2.95 (p = 0.052); 2.59 ± 3.08 vs. 5.25 ± 3.51 (p = 0.011); and 2.05 ± 2.94 vs. 4.90 ± 3.99 (p = 0.013), respectively. No adverse events were detected in either group. Our findings revealed a strong positive correlation between the pain scores on the N-PASS and two other scales (NFCS and NIPS), which was statistically significant (p < 0.01).

NNS is considered a safe and effective pain-relief method during the heel prick procedure in term neonates, demonstrated using the N-PASS. These findings were correlated with the pain evaluation by NFCS and NIPS.