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

Abstract The objective was to determine if consistent pain management during vaccine injections has a beneficial effect on future infant pain reactivity. This was a multicentre, 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 + oral sucrose solution (sucrose), 4) video + sucrose + topical liposomal lidocaine (lidocaine). At 15 month vaccinations, all active pain interventions were administered (video + sucrose + 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 (MBPS) (range, 0-10). Altogether, 352 infants participated; characteristics did not differ among groups (p>0.05). Pain scores did not differ among groups during baseline (p=0.642), needle injection (p=0.739), or recovery (p=0.750) 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.