A Longitudinal Randomized Trial of the Effect of Consistent Pain Management for Infant Vaccinations on Future Vaccination Distress

The objective was to determine if consistent pain management during vaccine injections has a beneficial effect on future infant pain reactivity. This was a multicenter, longitudinal, double-blind, double-dummy, add-on, randomized controlled trial. Healthy infants were randomized to 1 of 4 add-on pain management regimens for all vaccinations in the first year of life: 1) placebo control (standard care), 2) parent video education about infant soothing (video), 3) video and oral sucrose solution (sucrose), 4) video and sucrose and topical liposomal lidocaine (lidocaine). At 15-month vaccinations, all active pain interventions were administered (video and sucrose and lidocaine); however, individuals remained blinded to the original treatments given. Pain at 15 months was evaluated during 3 procedure phases (baseline, needle injection, and recovery) by a researcher unaware of group allocation using a validated measure, the Modified Behavioural Pain Scale (range, 0–10). Altogether, 352 infants participated; characteristics did not differ among groups (P > .05). Pain scores did not differ among groups during baseline (P = .642), needle injection (P = .739), or recovery (P = .750) phases. In conclusion, there was no evidence of a long-term benefit of consistent use of pain interventions in the first year of life on future infant pain responsivity at 15-month vaccinations. This randomized controlled trial did not find a long-term benefit of consistent pain management during infant vaccinations on future infant pain responsivity at 15 months. The results are relevant to clinicians and researchers studying and evaluating pain interventions in children undergoing medical procedures. •Consistent pain management during infant vaccinations had no long-term benefit.•There was no difference in infant reactivity at future vaccinations at 15 months.•Future research should target the effect of analgesia in older children.