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Pain reactivity in preterm neonates: examining the sex differences
B O Valeri1, C M Gaspardo, F E Martinez
1Department of Neuroscience and Behavior, Ribeirão Preto Medical School, University of São Paulo, Brazil.
Insights
Male and female preterm infants show similar behavioral pain responses. However, males exhibited higher heart rate reactivity during painful procedures, suggesting potential sex-based physiological differences in neonatal pain sensitivity.
Area of Science:
- Neonatal care
- Pain research
- Developmental pediatrics
Background:
- Neonatal Intensive Care Unit (NICU) hospitalizations expose vulnerable newborns to early and repeated pain.
- Neonatal pain responses are influenced by various factors encountered by neonates.
Purpose of the Study:
- To test the hypothesis that male preterm neonates exhibit greater pain sensitivity than females.
- To assess biobehavioral pain reactivity and recovery patterns in response to painful procedures.
Main Methods:
- Observed 53 preterm, low birthweight infants in the NICU across five phases: baseline, antisepsis, puncture, recovery-dressing, and recovery-resting.
- Measured behavioral pain reactivity using the Neonatal Facial Coding System (NFCS) and Sleep-Wake States Scale (SWS).
- Continuously recorded heart rate (HR) and assessed scores and magnitude of responses.
Main Results:
- No statistical differences were found between male and female preterm neonates in NFCS and SWS scores, indicating similar behavioral pain reactivity and recovery patterns.
- Male preterm infants showed higher HR during the initial minute of the puncture phase compared to females.
- Male preterm infants exhibited a greater change in maximum HR from baseline to puncture phase than female preterm infants.
Conclusions:
- While male infants demonstrated higher physiological reactivity (HR parameters) to painful stimuli than females, the findings were insufficient to confirm sex influence on biobehavioral pain response in vulnerable neonates.
- Further research is needed to fully elucidate the role of sex in neonatal pain perception and response.
Background:
Early and repeated experiences of pain may have long-term effects on vulnerable newborns hospitalized in the Neonatal Intensive Care Unit (NICU), and neonatal pain responses may be affected by a variety of factors that neonates encounter. We tested the hypothesis that male preterm neonates exhibited greater pain sensitivity than females by assessing biobehavioural pain reactivity and recovery patterns to painful procedure.
Methods:
Fifty-three infants born preterm and low birthweight who were admitted to NICU were observed during five phases (baseline, antisepsis, puncture, recovery-dressing and recovery-resting). Behavioural pain reactivity was measured using the Neonatal Facial Coding System (NFCS) and the Sleep-Wake States Scale (SWS). The heart rate (HR) was continuously recorded. All measures were assessed based on scores and magnitude of responses.
Results:
We found that male and female preterm neonates had similar patterns of behavioural pain reactivity and recovery; there were no statistical differences between groups in NFCS and SWS scores. However, male preterm infants presented higher HR immediately in the first minute of the puncture phase and also higher change in maximum HR between the baseline and puncture phases, than female preterm infants.
Conclusion:
Although we found that male infants showed higher physiological reactivity to painful stimulus in some HR parameters than female infants, the evidences were not sufficient to confirm the influence of sex on biobehavioural response to pain in vulnerable neonates.
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