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Published on: February 9, 2024
Comparison of distress and pain in infants randomized to groups receiving standard versus multiple immunizations
Denise Hanson1, Wendy Hall, Leslie L Mills
1Vancouver Coastal Health, Pacific Spirit Health Centre, 2110 West 43rd Avenue, Vancouver, BC V6M 2E1, Canada.
Insights
Simultaneous immunizations significantly reduced pain behaviors in 4-month-old infants compared to sequential shots. Further research could explore long-term effects on pain sensitivity.
Area of Science:
- Pediatrics
- Immunology
- Pain Management
Background:
- Infants undergo multiple immunizations around 4 months of age.
- Painful stimuli in infancy may have long-term implications for pain sensitivity and stress responses.
Purpose of the Study:
- To compare infant distress and pain between sequential and simultaneous immunization schedules.
- To assess the impact of immunization timing on physiological stress markers.
Main Methods:
- A randomized controlled trial involving 4-month-old infants.
- Comparison of sequential (control) versus simultaneous (experimental) administration of three immunizations.
- Measurement of salivary cortisol and Neonatal Infant Pain Scale (NIPS) scores.
Main Results:
- Both groups showed increased cortisol, but no significant difference between groups.
- The simultaneous immunization group exhibited significantly lower NIPS pain scores (p=0.003).
- Simultaneous injections effectively reduced pain behavior responses.
Conclusions:
- Simultaneous administration of 4-month immunizations appears effective in reducing acute pain behaviors in infants.
- Longitudinal studies are warranted to investigate potential long-term effects of reduced infant pain exposure on pain sensitivity and stress.
Abstract:
This randomized controlled trial compared distress and pain in healthy 4-month-old infants receiving three different immunizations either sequentially (control, n=50) or simultaneously, two at the same time, followed by the third (experimental, n=51). Although both groups demonstrated a significant increase in cortisol from baseline levels, the lack of significant difference on salivary cortisol between groups post-immunization suggests the study was underpowered. On NIPS scores, the experimental group demonstrated significantly less pain (Mann-Whitney U=1648.0, p=0.003). Simultaneous injections appeared to be effective in reducing pain behavior responses in infants receiving their 4-month immunizations. Longitudinal studies could determine whether reduced exposure to pain in infancy, through simultaneous immunization injections, could contribute to a reduction in sensitivity to pain and physiologic stress responses.
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