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Effects of a tripartite intervention on biological stress in preterm infants during heel pricks for newborn
Ti Yin1,2, Jen-Jiuan Liaw1, Chiung-Hsi Tien3,4
1School of Nursing, National Defense Medical Center, Taipei, Taiwan.
Insights
A tripartite intervention significantly reduced stress in preterm infants during heel pricks. This method, combining behavioral state modulation, nonnutritive sucking, and tucking, lowered salivary cortisol levels compared to usual care.
Area of Science:
- Neonatal care
- Pediatric pain management
- Stress physiology
Background:
- Procedural pain, such as heel pricks, is a significant stressor for preterm infants.
- Elevated salivary cortisol levels (SCLs) are a physiological indicator of stress in neonates.
- Non-pharmacological interventions are sought to mitigate procedural pain and stress in vulnerable infant populations.
Purpose of the Study:
- To evaluate the efficacy of a tripartite intervention (behavioral state modulation, nonnutritive sucking, tucking) in reducing stress during heel pricks in preterm infants.
- To compare salivary cortisol level changes between infants receiving the tripartite intervention and those receiving standard care.
Main Methods:
- A prospective randomized trial involving 64 preterm infants in Level III neonatal care units.
- Infants were randomly assigned to either a control group (usual care) or an intervention group (tripartite intervention).
- Salivary cortisol levels were measured immediately before (T0) and 20 minutes after (T1) heel pricks at two stages: 48 hours after birth and at ≥37 weeks' gestation.
Main Results:
- The tripartite intervention group showed a significantly lower increase in salivary cortisol levels from T0 to T1 at Stage 1 compared to the control group (p < 0.001).
- The reduction in the change of SCLs between Stage 1 and Stage 2 was significantly greater in the intervention group than in the control group (p = 0.026).
- The intervention effectively decreased the rise in SCLs, indicating reduced stress response to heel pricks.
Conclusions:
- The tripartite intervention is effective in significantly decreasing the stress response, as indicated by lower salivary cortisol levels, in preterm infants undergoing heel pricks.
- The intervention is easily implementable by clinicians for heel-stick procedures.
- Further replication studies are recommended before widespread clinical adoption for routine heel sticks and other painful procedures.
Abstract:
This prospective randomized trial examined the effects of a tripartite intervention (behavioral state modulation + nonnutritive sucking + tucking) on stress from procedural pain during heel pricks. Blood samples for routine screening were collected by heel pricks 48 h after birth (Stage 1) and at ≥37 weeks' gestation (Stage 2); salivary cortisol levels (SCLs) pre-prick (T0) and 20 min post-prick (T1) assessed stress. Preterm infants (n = 64) sampled by convenience at Level III neonatal care units were randomly assigned to the control condition (usual care) or intervention condition (tripartite intervention). Generalized estimating equations examined differences in salivary cortisol between conditions. After adjusting for effects of gestational age, postmenstrual age, and baseline SCLs, (1) at Stage 1, the change in salivary cortisol from T0 to T1 in preterm infants who received the tripartite intervention was, on average, significantly lower by 0.431 units (log scale) than the change in preterm infants who received the control condition (p < 0.001); (2) in the tripartite intervention condition, the difference between the change in mean SCLs from T0 to T1 at Stages 1 and 2 was significantly lower by 0.287 units (log scale), on average than between the change at Stages 1 and 2 in the control condition (p = 0.026). The provision of a tripartite intervention during heel prick significantly decreased the raise of SCLs compared with infants receiving usual care, suggesting lower stress. Clinicians could easily implement the tripartite intervention for heel-stick support; however, replication is needed before recommending its incorporation into routine heel stick and other stressful procedures.
