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Preterm newborn pain research review
1Touch Research Institute, University of Miami/Miller School of Medicine, United States; Fielding Graduate University, United States.
Insights
Preterm newborns experience numerous painful procedures, often without pain relief. This review highlights the significant short- and long-term developmental effects of this pain and discusses potential therapies.
Area of Science:
- Neonatal Medicine
- Developmental Psychology
- Pain Management
Background:
- Preterm newborns undergo frequent painful procedures, with 79% receiving them without analgesia.
- A median of 75 painful procedures occur during hospitalization, averaging up to 51 per day.
Purpose of the Study:
- To review current research on preterm newborn pain, including assessment methods, short- and long-term effects, and therapeutic interventions.
- To identify gaps in the research regarding the long-term impact of pain and the efficacy of various therapies.
Main Methods:
- A narrative review of literature from PubMed and PsycINFO.
- Focus on studies published within the last ten years regarding preterm newborn pain.
Main Results:
- Immediate effects include increased heart rate, oxidative stress, cortisol, and decreased vagal activity.
- Developmental outcomes show effects as early as 32 weeks gestation (lower body weight/head circumference) and by eight months (thinner gray matter, motor/cognitive delays).
- Longer-term effects at school age include reduced cortical thickness, lower vagal activity, impaired visual-perceptual development, lower IQs, and internalizing behaviors.
Conclusions:
- Pharmacological and non-pharmacological therapies like sucrose, nonnutritive sucking, and full-body interventions show promise for immediate pain relief.
- More research is needed on the routine use of non-pharmacological therapies for long-term pain reduction and additional randomized controlled trials.
Abstract:
This narrative review is based on a literature search of PubMed and PsycINFO for research on preterm newborn pain published during the last ten years. The high prevalence of painful procedures being performed with preterm newborns without analgesia (79%), with a median of 75 painful procedures being received during hospitalization and as many as 51 painful procedures per day highlights the importance of this problem. This review covers the pain assessments that have been developed, the short-term effects of the painful procedures, the longer-term developmental outcomes and the pharmacological and alternative therapies that have been researched. The most immediate effects reported for repeated painful procedures include increased heart rate, oxidative stress and cortisol as well as decreased vagal activity. Lower body weight and head circumference have been noted at 32 weeks gestation. Blunted cortisol reactivity to stressors has been reported for three-month-olds and thinner gray matter in 21 of 66 cerebral regions and motor and cognitive developmental delays have been noted as early as eight months. Longer-term outcomes have been reported at school age including less cortical thickness, lower vagal activity, delayed visual- perceptual development, lower IQs and internalizing behavior. Pharmacological interventions and their side effects and non-pharmacological therapies are also reviewed including sucrose, milk and nonnutritive sucking which have been effective but thought to negatively affect breast-feeding. Full-body interventions have included tucking, swaddling, kangaroo care and massage therapy. Although these have been effective for alleviating immediate pain during invasive procedures, research is lacking on the routine use of these therapies for reducing long-term pain effects. Further, additional randomized controlled replication studies are needed.
