Acute effects of maternal skin-to-skin contact and massage on saliva cortisol in preterm babies

A systematic review and multivariate meta-analysis of the physical and mental health benefits of touch interventions

Receiving touch is of critical importance, as many studies have shown that touch promotes mental and physical well-being. We conducted a pre-registered (PROSPERO: CRD42022304281) systematic review and multilevel meta-analysis encompassing 137 studies in the meta-analysis and 75 additional studies in the systematic review (n = 12,966 individuals, search via Google Scholar, PubMed and Web of Science until 1 October 2022) to identify critical factors moderating touch intervention efficacy. Included studies always featured a touch versus no touch control intervention with diverse health outcomes as dependent variables. Risk of bias was assessed via small study, randomization, sequencing, performance and attrition bias. Touch interventions were especially effective in regulating cortisol levels (Hedges' g = 0.78, 95% confidence interval (CI) 0.24 to 1.31) and increasing weight (0.65, 95% CI 0.37 to 0.94) in newborns as well as in reducing pain (0.69, 95% CI 0.48 to 0.89), feelings of depression (0.59, 95% CI 0.40 to 0.78) and state (0.64, 95% CI 0.44 to 0.84) or trait anxiety (0.59, 95% CI 0.40 to 0.77) for adults. Comparing touch interventions involving objects or robots resulted in similar physical (0.56, 95% CI 0.24 to 0.88 versus 0.51, 95% CI 0.38 to 0.64) but lower mental health benefits (0.34, 95% CI 0.19 to 0.49 versus 0.58, 95% CI 0.43 to 0.73). Adult clinical cohorts profited more strongly in mental health domains compared with healthy individuals (0.63, 95% CI 0.46 to 0.80 versus 0.37, 95% CI 0.20 to 0.55). We found no difference in health benefits in adults when comparing touch applied by a familiar person or a health care professional (0.51, 95% CI 0.29 to 0.73 versus 0.50, 95% CI 0.38 to 0.61), but parental touch was more beneficial in newborns (0.69, 95% CI 0.50 to 0.88 versus 0.39, 95% CI 0.18 to 0.61). Small but significant small study bias and the impossibility to blind experimental conditions need to be considered. Leveraging factors that influence touch intervention efficacy will help maximize the benefits of future interventions and focus research in this field.

Associations between parental involvement at bedtime and young children's evening cortisol and nighttime sleep

Parents are theorized to play an important role in helping young children to downregulate arousal to achieve sufficient and good-quality sleep. To my knowledge, however, the links between parenting and children's physiological arousal at bedtime and subsequent nighttime sleep have not been empirically tested. The present study examined 3- to 6-year-old children's evening cortisol levels as a pathway linking parental involvement at bedtime to children's nighttime sleep duration and quality. Fifty-one children (53% male, 47% female; 80% White, 18% Biracial, 2% Black) and their families participated. Parental involvement (presence, contact, quiet activities) was assessed by raters from video recordings of one night of bedtime. Children's evening cortisol levels were measured from saliva samples taken at bedtime by parents across three nights. Children's nighttime sleep (minutes, efficiency) was determined from an actigraph worn the same three nights. Path analyses controlling for child and family demographics provided support for three significant indirect effects: lower child evening cortisol acted as a pathway linking greater parental presence at bedtime to more child nighttime sleep minutes and higher sleep efficiency, and lower child evening cortisol also linked greater parental contact at bedtime to higher sleep efficiency. Among this low-risk sample, the findings suggest that encouraging parental involvement in young children's bedtime routine may promote healthy sleep by way of reduced child physiological arousal.

Skin-to-skin contact to support preterm infants and reduce NICU-related stress

OBJECTIVE

Hospitalization in the neonatal intensive care unit (NICU) with numerous painful medical interventions, being separated from parents, leads to the high risk of chronic stress for preterm infants. Today, many NICUs use more appropriate developmental care and pain management, but the early and long-term outcomes of stress in these vulnerable infants require searching for more stress-reducing interventions in neonatal care. The objective of the study was to investigate how skin-to-skin contact (SSC) can influence the biologic stress levels in preterm infants in the NICU by assessing cortisol and oxytocin levels.

PARTICIPANTS AND METHODS

The study included 71 preterm infants with gestational age less than 34 + 0/7 weeks who were recruited from level III NICU. The overall design was a baseline-response design. Saliva and urine were collected before (baseline) and after skin-to-skin contact to measure salivary cortisol and urinary oxytocin by enzyme immunoassay method.

RESULTS

The infants' baseline hormonal status was represented by the following indicators: the level of salivary cortisol was 0.402 [0.227; 1,271] μg/dl, urinary oxytocin 48.88 [32.97; 88.11] pg/ml. There was a decrease in salivary cortisol levels to 0.157 [0.088; 0.351] μg/dl compared to baseline (p ˂ 0.001) with a simultaneous increase of the urinary oxytocin level -73.59 [45.18; 108.8] pg/ml (p = 0.028) in response to SSC.

CONCLUSION

Preterm infants in the NICU experience significant stress, characterized by hormonal imbalance: an increased level of the stress hormone cortisol and a decreased level of the anti-stress hormone oxytocin. Skin-to-skin contact helps to ameliorate the hormonal stress in preterm infants by activating the oxytocin release with simultaneous reduction of cortisol secretion.

Consequences of Prematurity on Cortisol Regulation and Adjustment Difficulties: A 9-Year Longitudinal Study

A preterm birth represents a stressful event having potentially negative long-term consequences. Thirty-three children born preterm (<33 weeks gestational age) and eleven full-term children participated in a nine-year longitudinal study. Perinatal Risk Inventory (PERI) was used at birth to assess the perinatal stress. Salivary cortisol, collected four times a day over two consecutive days, was measured with radioimmunoassay technique at six months and nine years to assess the hypothalamic-pituitary-adrenal (HPA) axis. Mothers reported post-traumatic symptoms on a self-report questionnaire 12 months after their child's birth and children's adjustment problems at 9 years of child age on the Child Behavior Checklist. Results showed a significant difference in cortisol regulation at nine years between preterm and full-term children but no differences in adjustment problems. Whereas biological factors (i.e., PERI, cortisol regulation at six months) explained cortisol at nine years, maternal post-traumatic symptoms were predictive of adjustment problems in their child. In conclusion, very preterm birth has some long-term consequences on the HPA-axis regulation at nine years. Although cortisol regulation is mostly influenced by biological factors, the presence of maternal post-traumatic symptoms predicts the manifestation of adjustment problems in both groups. This shows the importance of maternal psychological well-being for child development. Further research is needed to understand the exact consequences of premature birth on cortisol regulation and the implication for the child's development and health.

Parent-Infant Skin-to-Skin Contact and Stress Regulation: A Systematic Review of the Literature

Several studies have focused on neonatal maternal separation (MS) to investigate behavioural and neuroendocrine reactions to lack of contact, but only a few have focused on early separation in the first days or weeks after birth. This literature review investigates the vital importance of contact and touch by exploring how skin-to-skin contact (SSC) regulates stress in the mother-infant relationship. Various databases such as PubMed, Scopus, and ScienceDirect were searched for literature published between 2015 and 2020. From 1141 articles, 22 were declared eligible. The reviewed articles showed how SSC regulates child stress by biological indicators such as the autonomic nervous system (ANS), heart rate variability (HRV), cortisol, and oxytocin. This research concludes the importance of SSC for stress regulation, especially during the COVID-19 pandemic. With no research to date indicating a possible risk of neonatal COVID-19 transmission following SSC, SSC should continue to be practiced for all women, as recommended by the WHO.

Capturing touch in parent-infant interaction: A comparison of methods

Naturally occurring high levels of caregiver touch promote offspring development in many animal species. Yet, caregiver touch remains a relatively understudied topic in human development, possibly due to challenges of measuring this means of interaction. While parental reports (e.g., questionnaires, diaries) are easy to collect, they may be subject to biases and memory limitations. In contrast, observing touch in a short session of parent-child interaction in the lab may not be representative of touch interaction in daily life. In the present study, we compared parent reports (one-off questionnaires and diary) and observation-based methods in a sample of German 6- to 13-month-olds and their primary caregivers (n = 71). In an attempt to characterize touching behaviors across a broad range of contexts, we measured touch both during play and while the parent was engaged in another activity. We found that context affected both the quantity and types of touch used in interaction. Parent-reported touch was moderately associated with touch observed in parent-child interactions and more strongly with touch used during play. We conclude that brief one-off questionnaires are a good indicator of touch in parent-child interaction, yet they may be biased toward representing particular daily activities and particular types of touch.

Premature Birth and Developmental Programming: Mechanisms of Resilience and Vulnerability

The third trimester of pregnancy represents a sensitive phase for infant brain plasticity when a series of fast-developing cellular events (synaptogenesis, neuronal migration, and myelination) regulates the development of neural circuits. Throughout this dynamic period of growth and development, the human brain is susceptible to stress. Preterm infants are born with an immature brain and are, while admitted to the neonatal intensive care unit, precociously exposed to stressful procedures. Postnatal stress may contribute to altered programming of the brain, including key systems such as the hypothalamic-pituitary-adrenal axis and the autonomic nervous system. These neurobiological systems are promising markers for the etiology of several affective and social psychopathologies. As preterm birth interferes with early development of stress-regulatory systems, early interventions might strengthen resilience factors and might help reduce the detrimental effects of chronic stress exposure. Here we will review the impact of stress following premature birth on the programming of neurobiological systems and discuss possible stress-related neural circuits and pathways involved in resilience and vulnerability. Finally, we discuss opportunities for early intervention and future studies.

Kangaroo mother care alters chromogranin A and perfusion index in preterm babies

BACKGROUND

While providing various benefits, concerns about the potential risks of kangaroo mother care, or skin-to-skin contact (SSC), between mother and her preterm infant hinder its widespread implementation in some resource- rich countries. In neonates, salivary chromogranin A (s-CgA) is elevated upon exposure to stress, whereas the perfusion index (PI) is associated with hemodynamics and peripheral perfusion. Here, we investigated the effects of SSC on s-CgA and the PI in preterm infants.

METHODS

Twelve infants were enrolled in the study. Factors associated with baseline s-CgA were analyzed. Baseline s-CgA and the level after SSC were compared. Secreted IgA in the saliva was compared as the control. The PI before, throughout, and after SSC were compared.

RESULTS

Baseline s-CgA was significantly lower in infants who were supplemented with baby formula milk in addition to breast milk before SSC (n = 2) compared with those fed with their mother's breast milk alone (n = 10, P = 0.03). SSC significantly decreased s-CgA in babies who were fed breast milk only before SSC (n = 10, P = 0.01) but not in those supplemented with formula milk before SSC (n = 2). Secreted IgA in saliva was not affected by SSC. The PI was significantly elevated during SSC (P = .01).

CONCLUSION

Our data indicate that SSC can reduce s-CgA levels when combined with mother's breast milk and increase the PI in preterm infants, thereby providing additional evidence of the benefit of SSC.

Neurophysiology of human touch and eye gaze in therapeutic relationships and healing: a scoping review

Objective:

The primary objective of this scoping review was to examine and map the range of neurophysiological impacts of human touch and eye gaze, and consider their potential relevance to the therapeutic relationship and to healing.

Introduction:

Clinicians, and many patients and their relatives, have no doubt as to the efficacy of a positive therapeutic relationship; however, much evidence is based on self-reporting by the patient or observation by the researcher. There has been little formal exploration into what is happening in the body to elicit efficacious reactions in patients. There is, however, a growing body of work on the neurophysiological impact of human interaction. Physical touch and face-to-face interaction are two central elements of this interaction that produce neurophysiological effects on the body.

Inclusion criteria:

This scoping review considered studies that included cognitively intact human subjects in any setting. This review investigated the neurophysiology of human interaction including touch and eye gaze. It considered studies that have examined, in a variety of settings, the neurophysiological impacts of touch and eye gaze. Quantitative studies were included as the aim was to examine objective measures of neurophysiological changes as a result of human touch and gaze.

Methods:

An extensive search of multiple databases was undertaken to identify published research in the English language with no date restriction. Data extraction was undertaken using an extraction tool developed specifically for the scoping review objectives.

Results:

The results of the review are presented in narrative form supported by tables and concept maps. Sixty-four studies were included and the majority were related to touch with various types of massage predominating. Only seven studies investigated gaze with three of these utilizing both touch and gaze. Interventions were delivered by a variety of providers including nurses, significant others and masseuses. The main neurophysiological measures were cortisol, oxytocin and noradrenaline.

Conclusions:

The aim of this review was to map the neurophysiological impact of human touch and gaze. Although our interest was in studies that might have implications for the therapeutic relationship, we accepted studies that explored phenomena outside of the context of a nurse-patient relationship. This allowed exploration of the boundary of what might be relevant in any therapeutic relationship. Indeed, only a small number of studies included in the review involved clinicians (all nurses) and patients. There was sufficient consistency in trends evident across many studies in regard to the beneficial impact of touch and eye gaze to warrant further investigation in the clinical setting. There is a balance between tightly controlled studies conducted in an artificial (laboratory) setting and/or using artificial stimuli and those of a more pragmatic nature that are contextually closer to the reality of providing nursing care. The latter should be encouraged.

Impact of Skin-to-Skin Parent-Infant Care on Preterm Circulatory Physiology

OBJECTIVES

To ascertain the impact of skin-to-skin care between parents and infants on cardiac function and cerebral blood flow in preterm infants.

STUDY DESIGN

We undertook a prospective study of 40 self-ventilating preterm infants at a quaternary center and assessed cardiac performance and cerebral blood flow. Assessments were carried out two hours before skin-to-skin care and then 60 minutes after skin-to-skin care (with the infant still on parent and turned supine).

RESULTS

Infants were 30.5 ± 0.6 weeks' gestational age and 1378 ± 133 g birthweight. Axillary temperature noted a nonsignificant increase during skin-to-skin care from 36.7 ± 0.07°C to 36.9 ± 0.07°C (P = .07). Cardiac contractility (right ventricular fractional area change [26.5% ± 0.3% vs 27.8% ± 0.4; P < .001] and tricuspid annular plane systolic excursion [0.73 ± 0.03 cm vs 0.77 ± 0.03 cm; P = .02]) increased significantly, coincident with decreased measures of pulmonary vascular resistance. An increase in systemic cardiac output was associated with increased cerebral blood flow and reduced middle cerebral artery resistive index (0.81 ± 0.02 vs 0.74 ± 0.02; P = .0001).

CONCLUSIONS

We documented a significant circulatory beneficial adaptation to a common neonatal practice. These findings align with previously documented physiologic benefits in cardiorespiratory stability and cardiac rhythm in preterm infants, and may be mediated through modulation of the autonomic nervous system.

Higher tactile sensitivity in preterm infants at term-equivalent age: A pilot study

Despite a growing body of research on perinatal sensory abilities, data on the extent of tactile sensitivity and more particularly passive touch (i.e. sensitivity to a stimulation imposed on the skin) are relatively limited, and the development and processing of tactile function are still thus little known. This question is particularly of high importance for infants with atypical early development such as those born prematurely who are exposed to many sensory (including tactile) stimulations (being in a hospital setting) during a critical period of brain development and those born at early term whose birth occurs at the precise time of cortical reorganization, in particular in the sensory areas. Some parents and health-care providers have for instance reported that children born prematurely exhibit atypical (e.g. higher) sensitivity to “benign” tactile stimuli. In the present study, we hypothesized that preterm and early-term infants may show altered tactile sensitivity. We compared the behavioral responses around term-equivalent age of infants born either pre-term, early-term or at term to the application of a light (0.008 grams) mechanical stimulus. We found that almost all preterm infants perceive this tactile stimulus, contrarily to the two other groups of infants. This extreme tactile sensitivity may be due to experiential, maturational or more likely both processes. We also compared the tactile sensitivity of these infants to that of adults. We found that adults were irresponsive to the light mechanical stimulus. This finding opens not only new insights in understanding development of tactile processing, but also new lines of thought about the particular sensory world of premature and early-term infants and hence about the potential impact of early care practices.

Effects of smelling amniotic fluid on preterm infant's pain and stress during peripheral cannulation: A randomized controlled trial

AIM

To investigate the effect of smelling amniotic fluid on preterm infants' pain and stress caused by peripheral cannulation.

METHODS

This was a randomized controlled trial. The study sample consisted of 80 preterm infants meeting the case selection criteria and infants were randomly assigned to each group. However, in addition to the infants excluded from the study, total number of the infants in all the groups was 61. Infants in the amniotic fluid group smelled amniotic fluid for 15 min before, during, and after the application of peripheral cannulation while those in the control group received routine care during the procedure. The Premature Infant Pain Profile was used to assess their pain levels, and salivary cortisol analysis was performed to evaluate stress levels.

RESULTS

Preterm infants in the amniotic fluid and control groups had similar baseline characteristics. However, the pain levels of infants in the amniotic fluid group were significantly lower than of those in the control group during and after the procedure. After the procedure, cortisol levels of the infants in the amniotic fluid group were lower than of those in the control group, although this difference was not significant.

CONCLUSION

The intervention of smelling amniotic fluid is a practice that can be used for reducing pain and stress of preterm infants during peripheral cannulation.

The human newborn's umwelt: Unexplored pathways and perspectives

Historically, newborns, and especially premature newborns, were thought to "feel nothing." However, over the past decades, a growing body of evidence has shown that newborns are aware of their environment, but the extent and the onset of some sensory capacities remain largely unknown. The goal of this review is to update our current knowledge concerning newborns' perceptual world and how ready they are to cope with an entirely different sensory environment following birth. We aim to establish not only how and when each sensory ability arises during the pre-/postbirth period but also discuss how senses are studied. We conclude that although many studies converge to show that newborns are clearly sentient beings, much is still unknown. Further, we identify a series of internal and external factors that could explain discrepancies between studies, and we propose perspectives for future studies. Finally, through examples from animal studies, we illustrate the importance of this detailed knowledge to pursue the enhancement of newborns' daily living conditions. Indeed, this is a prerequisite for assessing the effects of the physical environment and routine procedures on newborns' welfare.

Supporting Optimal Neurodevelopmental Outcomes in Infants and Children With Congenital Heart Disease

Improved survival has led to increased recognition of developmental delays in infants and children with congenital heart disease. Risk factors for developmental delays in congenital heart disease survivors may not be modifiable; therefore, it is important that lifesaving, high-technology critical care interventions be combined with nursing interventions that are also developmentally supportive. Implementing developmental care in a pediatric cardiac intensive care unit requires change implementation strategies and widespread support from all levels of health care professionals. This manuscript reviews developmentally supportive interventions such as massage, developmentally supportive positioning, kangaroo care, cue-based feeding, effective pain/anxiety management, and procedural preparation and identifies strategies to implement developmentally supportive interventions in the care of infants and children with congenital heart disease. Improving developmental support for these infants and children at high risk for developmental delay may improve their outcomes and help promote family-centered care.

Salivary Cortisol as a Biomarker of Stress in Mothers and their Low Birth Weight Infants and Sample Collecting Challenges

Background

Salivary cortisol measurement is a non-invasive method suitable for use in neonatal research. Mother-infant separation after birth represents stress and skin-to-skin contact (SSC) has numerous benefits. The aim of the study was to measure salivary cortisol in mothers and newborns before and after SSC in order to assess the effect of SSC on mothers’ and infants’ stress and to estimate the efficacy of collecting small saliva samples in newborns.

Methods

Salivary cortisol was measured in 35 mother-infant pairs before and after the first and the fifth SSC in small saliva samples (50 μL) using the high sensitivity Quantitative ELISA-Kit (0.0828 nmol/L) for low cortisol levels detection. Samples were collected with eye sponge during 3 to 5 minutes.

Results

Cortisol level in mothers decreased after SSC: the highest levels were measured before and the lowest after SSC and the differences in values were significant during both the first (p<0.001) and the fifth SSC (p<0.001). During the first SSC the cortisol level decrease was detected in 14 (40%) and an increase in 21 (60%) newborns, and during the fifth SSC a decrease was detected in 16 (45.7%) and an increase in 19 (54.3%) newborns, without confirmed significance of the difference. Saliva sampling efficacy using eye sponge was 75%.

Conclusions

Cortisol level decrease in mothers proves the stress reduction during SSC, while variable cortisol levels in infants do not indicate stress reduction and imply the need for further research. The used sampling method appeared to be one of the most optimal considering the sample volume, sampling time and efficacy.

Neonatal pain and reduced maternal care: Early-life stressors interacting to impact brain and behavioral development

Advances in neonatal intensive care units (NICUs) have drastically increased the survival chances of preterm infants. However, preterm infants are still exposed to a wide range of stressors during their stay in the NICU, which include painful procedures and reduced maternal contact. The activation of the hypothalamic-pituitary-adrenal (HPA) axis, in response to these stressors during this critical period of brain development, has been associated with many acute and long-term adverse biobehavioral outcomes. Recent research has shown that Kangaroo care, a non-pharmacological analgesic based on increased skin-to-skin contact between the neonate and the mother, negates the adverse outcomes associated with neonatal pain and reduced maternal care, however the biological mechanism remains widely unknown. This review summarizes findings from both human and rodent literature investigating neonatal pain and reduced maternal care independently, primarily focusing on the role of the HPA axis and biobehavioral outcomes. The physiological and positive outcomes of Kangaroo care will also be discussed in terms of how dampening of the HPA axis response to neonatal pain and increased maternal care may account for positive outcomes associated with Kangaroo care.

Kangaroo care by fathers and mothers: comparison of physiological and stress responses in preterm infants

OBJECTIVE

To compare physiological and biochemical responses in stable preterm neonates and their parents following kangaroo mother care (KMC) and kangaroo father care (KFC).

STUDY DESIGN

We conducted a prospective cross-over design study of stable preterm neonates of <35 weeks gestation in a tertiary Neonatal Unit in Toronto. All neonates received KMC and KFC for 1 h on consecutive days in a random order. Heart rate, temperature, blood pressure, oxygen saturation and salivary cortisol in infants before and after kangaroo care and heart rate, temperature and salivary cortisol in parents before and after kangaroo care were measured. Pairwise comparisons of changes in these measures were analyzed.

RESULT

Twenty-six sets of neonates and their parents were studied for physiological parameters, of which 19 had adequate samples for salivary cortisol assessment. The infants had a mean birth weight of 1096 g (s.d.=217) and a mean postmenstrual age at study of 32 weeks (s.d.=2). There were no significant differences in the changes in mean heart rate (P=0.51), temperature (P=0.37), oxygen saturation (P=0.50), systolic blood pressure (P=0.32), mean blood pressure (0.10) and salivary cortisol (P=0.50) before and after KMC or KFC in the neonates. The changes in mean heart rate (P=0.62), temperature (P=0.28) and salivary cortisol (P=0.59) before and after kangaroo care were similar between mothers and fathers.

CONCLUSION

No significant differences in physiological and stress responses were identified following KMC or KFC in preterm neonates. KFC may be as safe and as effective as KMC.

An experimental study on mother-infant skin-to-skin contact in full-terms

In premature infants, daily skin-to-skin contact (SSC) has various beneficial effects on the health of the infant and the mother. These beneficial effects might extend to full-term infants. This experimental within-subject study examines the immediate effects of SSC on full-terms' cortisol physiology during SSC and subsequent physiological and behavioral reactions to a mild stressor (a bathing session). Additionally, the effects of SSC on the quality of maternal behavior are examined. Between 5 and 7 weeks postpartum, 17 full-term infant-mother dyads were visited at home twice. During one home visit, a bathing session was proceeded by 50min of mother-infant SSC, while during the other visit the bathing session was proceeded by 50min of the infant resting alone. The order of the home visits was counterbalanced. Infant salivary cortisol measures were taken to measure the cortisol response to the experimental condition (SSC versus solitary resting) and the bathing session. Furthermore, infant behavioral distress and the quality of maternal behavior during the bathing session were scored from videotapes. Two-way within-subject repeated measures ANOVA's showed that, when compared to solitary resting, full-terms' cortisol concentrations significantly decreased during SSC, followed by higher cortisol reactivity in response to the subsequent bathing session. No effects of SSC on infant behavioral distress and maternal caregiving behavior were found. Apparently, a single session of mother-infant SSC can affect infant cortisol physiology in full-term infants. Future SSC research is needed to investigate the neurobiological mechanisms and dose-response relations in full-term infants.

The Relationship between Gentle Tactile Stimulation on the Fetus and Its Temperament 3 Months after Birth

OBJECTIVE

The aim of this study was to evaluate the effect of gentle tactile stimulation on the fetus in its temperament 3 months after birth.

METHOD

A total of 302 mother-3-month-infant dyads enrolled the retrospective cohort study. 76 mothers had regular gentle tactile stimulation on the fetus in their pregnancy; 62 mothers had irregular tactile stimulation on the fetus, and the rest of 164 mothers who had no tactile stimulation served as nonexposure group. Temperament was assessed using the EITS (a nine-dimensional scale of temperament).

RESULTS

Significant difference in temperament type was found among infants in 3 groups at 3 months of age. In the regular practice group, the babies with easy type temperament accounted for 73.7%, which was higher than that in irregular practice group (53.2%, P = 0.012) and that in the control group (42.1%, P < 0.001). Compared to infants in no practice group, the infants who had received regular gentle tactile stimulation before birth were lower in negative mood (P = 0.047) while higher in adaptability (P < 0.001), approach (P = 0.001), and persistence (P = 0.001), respectively.

CONCLUSION

Regular gentle tactile stimulation on fetus may promote the formation of easy type infant temperament.

Live music reduces stress levels in very low-birthweight infants

AIM

Music might benefit preterm infants in stressful, intensive care environments. However, data on stress level indicators, determined by salivary cortisol levels, are scarce. We evaluated the effect of live harp music on the stress level indicators of preterm infants in a neonatal intensive care unit (NICU).

METHODS

We exposed 20 stable preterm infants to music for 15 min on three consecutive days. Saliva was collected before the music was played and 25 min and 4 h after it ended. Salivary cortisol levels were measured by liquid chromatography-tandem mass spectrometry and vital signs, oxygen saturation, bradycardia, apnoeas and oxygen desaturations were recorded. Pain levels were assessed by the Bernese Pain Scale for Neonates.

RESULTS

Salivary cortisol was significantly lower 25 min (18.9 nmol/L [3.9-35.6] p = 0.001) and 4 h after music (17.4 nmol/L [3.9-35.3] p = 0.003) than at baseline 4 h before exposure (19.5 nmol/L [7.2-51.1]). After music, the number of apnoeas and oxygen desaturations was significantly reduced on all three, days and the number of bradycardia episodes on day one. Pain scores significantly improved after music on all 3 days.

CONCLUSION

Exposure to live music reduced salivary cortisol and had beneficial effects on the physiologic parameters of stable preterm infants in a NICU.

Nasopharyngeal suctioning does not produce a salivary cortisol reaction in preterm infants

AIM

To investigate whether nasopharyngeal suctioning produces a physiological and behavioural stress reaction in preterm infants and if a possible reaction can be dampened by sweet solution.

METHODS

Eleven preterm infants were randomly assigned to receive either 30% oral glucose or nothing prior to morning nasopharyngeal suctioning; the procedure was reversed in the afternoon. The study included a total of 44 samples from preterm infants evaluated with salivary cortisol, pain score (Visual Analogue Scale), heart rate, oxygen saturation and recovery time through the Newborn Individualized Developmental Care and Assessment Program. For reference, 44 samples from eleven full-term infants were evaluated for salivary cortisol.

RESULTS

Regardless of whether or not preterm infants received glucose before nasopharyngeal suctioning, no statistically significant difference was found in salivary cortisol reactivity, pain score, heart rate, oxygen saturation or recovery time. Nor were any statistically significant differences between salivary cortisol baseline and response values found in full-term infants after nasopharyngeal suctioning.

CONCLUSION

In the present setting, nasopharyngeal suctioning was not stressful enough to increase salivary cortisol or pain score. Oral glucose did not alter salivary cortisol levels.

The Stockholm Neonatal Family-Centered Care Study: effects on salivary cortisol in infants and their mothers

BACKGROUND

Parental involvement in the care of preterm infants in neonatal intensive care units (NICUs) is common, but little is known about the effect on stress responses in mothers and infants.

AIMS

The aim of this study is to evaluate the effect of family-centered care on salivary cortisol reactivity in mothers and preterm infants and the correlation between the mothers' and the preterm infants' salivary cortisol levels.

METHODS

This study is part of a randomized controlled trial conducted at two level-II NICUs, including Family Care (FC), where parents were able to stay 24h/day from admission to discharge, and Standard Care (SC). To investigate the cortisol response, saliva was collected from 289 preterm infants and their mothers before and after a diaper change at the time of discharge.

RESULTS

No significant differences were found between the two groups in salivary cortisol reactivity, either in mothers or in infants. The results revealed a correlation between preterm infants' and their mothers' baseline and response cortisol in the FC group: r=0.31 (p=0.001) and r=0.24 (p=0.01), respectively. Such correlation was not observed in the SC group: r=0.14 (p=0.14) and r=0.18 (p=0.07), respectively.

CONCLUSIONS

Family-centered care had no effect on salivary cortisol reactivity during diaper change. However, sharing the same environment may increase the concordance between preterm infants' and their mothers' salivary cortisol levels.

Social regulation of the stress response in the transitional newborn: a pilot study

The purpose of the study was to explore relationships between caregiver holding and feeding behaviors and the transitional newborn infant's cortisol response. Behaviors of 46 mothers, fathers, and their term transitional newborn infants were measured with the Index of Mother-Infant Separation (IMIS). Repeated measures of infant salivary cortisol were used to calculate area under the curve. A higher percentage of observations in which mother was holding infant was related to lower infant total cortisol during the first 6 hours after birth (r = -.24, p = .05, one-tailed).

Comparison of salivary cortisol, heart rate, and oxygen saturation between early skin-to-skin contact with different initiation and duration times in healthy, full-term infants

BACKGROUND

There are few studies that compare the physiological and biological efficacies between different early skin-to-skin contacts (SSC) post birth.

AIM

To investigate physiologically and biochemically how early SSC with different initiation and duration time influence the stress post birth for full-term infants.

STUDY DESIGN

Non-experimental study.

SUBJECTS

Study I; Thirty-two infants who began SSC 5 min or less [birth SSC, mean initiation time (standard deviation): 1.6 (1.1) min] after birth and 36 infants who did so more than 5 min [very early SSC, 26.3 (5.0) min] in heart rate (HR) and oxygen saturation (SpO(2)) analysis. Study II; Eighteen infants who underwent SSC for 60 min or less [mean initiation time: 7.5 (12.2) min] and 61 infants who did so for more than 60 min [15.3 (12.5) min] in salivary cortisol analysis.

OUTCOME MEASURES

HR and SpO(2) measured for 30 min post birth. Salivary cortisol concentration measured at 1 min, 60 min, and 120 min post birth.

RESULTS

Birth SSC group reached HR stability of 120-160 bpm significantly faster than very early SSC group by Kaplan-Meier analysis (P=0.001 by log-rank test). As for SpO(2) stability of 92% and 96%, no significantly between-group difference was found. Salivary cortisol levels were significantly lower between 60 and 120 min after birth in SSC group, continuing for more than 60 min compared with SSC group for 60 min or less after adjustment for salivary cortisol level at 1 min besides the infant stress factors (P=0.046).

CONCLUSIONS

Earlier SSC beginning within 5 min post birth and longer SSC continuing for more than 60 min within 120 min post birth are beneficial for stability of cardiopulmonary dynamics and the reduction of infant stress during the early period post birth.

Randomized crossover trial of kangaroo care to reduce biobehavioral pain responses in preterm infants: a pilot study

Kangaroo care (KC), skin-to-skin contact between mother and infant, is a promising method for blunting pain responses. This crossover pilot tested KC effects on biobehavioral responses to heel stick in preterm infants (30-32 weeks' gestational age, 2-9 days old) measured by Premature Infant Pain Profile (PIPP) and salivary and serum cortisol. Mother-infant dyads were randomly assigned to KC heel stick (KCH) first or incubator heel stick (IH) first. Study 1 (80-min study, N = 18) tested the effect of 80 min of KC before and throughout the heel stick procedure versus incubator care. Study 2 (30-min study, N = 10) tested 30 min of KC before and throughout the heel stick versus incubator care. KCH and IH began during a premeasurement phase and continued through four data collection phases: baseline, heel warming, heel stick, and recovery. PIPP responses were measured every 30 s during data collection; salivary cortisol was measured at the end of baseline and recovery; and serum cortisol was measured during heel stick. Study 1 showed no differences between KCH and IH. Study 2 showed lower PIPP scores at four time points during recovery (p < .05 to p < .001), lower salivary cortisol at the end of recovery (p < .05), and lower serum cortisol during heel stick for the KCH condition (p < .05) as well as clinically lower PIPP scores in the KCH condition during heel stick. Thirty minutes of KC before and throughout the heel stick reduced biobehavioral responses to pain in preterm infants.

A pilot study of a nursing intervention protocol to minimize maternal-infant separation after Cesarean birth

OBJECTIVE

To pilot test a standardized intraoperative and postoperative nursing intervention protocol to minimize maternal-infant separation after Cesarean.

DESIGN

Randomized-controlled trial.

SETTING

A 250-bed acute care community hospital labor/delivery/recovery/postpartum unit with approximately 150 repeat Cesarean deliveries per year.

PARTICIPANTS

Fifty women having a live, term, singleton, repeat Cesarean delivery and their newborns.

INTERVENTION

A standardized nursing intervention protocol was designed and administered to minimize the amount of maternal-infant spatial, tactile, olfactory, auditory, and visual separation post-Cesarean.

MAIN OUTCOME MEASURES

Maternal outcomes included maternal pain, anxiety, and childbirth perception. Infant outcomes included respiratory rate, temperature, stress (infant salivary cortisol), and breastfeeding rates.

RESULTS

Compared with the control group, the intervention group experienced earlier first physical contact and feedings and a longer interval until the infant first bath. Differences were found between treatment groups for infant temperatures and respiratory rates. Three infants in the control group experienced suboptimal temperatures. Infants in the intervention group had significantly higher salivary cortisol levels but were within the normal upper level range. No differences were noted in maternal pain, maternal anxiety, or perception of birth experience among treatment groups.

CONCLUSIONS

The pilot was valuable in examining intervention feasibility, appropriate outcome measures, and data collection strategies. The standardized intervention protocol shows promise for positively affecting maternal-infant outcomes after Cesarean delivery and merits further testing.

Application of Psychobiological Measures in Occupational Science and Occupational Therapy Research

The authors discuss the use of psychobiological measures (i.e., biomarkers) for furthering understanding of the biological foundations supporting human occupational behavior. They explore the possible applications of psychobiological measures in research relevant to occupational therapy practice and occupational science, including the documentation of outcomes following occupational therapy intervention. Common psychobiological measures that are available and of particular interest to occupational scientists and therapists are described based on a review of research that has applied psychobiological measures. Psychobiological measures have rarely been reported in the occupational science and occupational therapy literature to date, although such measures are beginning to emerge as researchers expand their questions and methods related to occupational engagement. Psychobiological measures may provide promising insights into the effectiveness of interventions designed to improve self-regulation and more effectively manage stressors for enhancing occupational performance. These measures also may be used to increase understanding of how participation in desired occupations influences arousal levels, stress response, and overall states of well-being and productivity.

The development of potentially better practices to support the neurodevelopment of infants in the NICU

OBJECTIVE

To review the existing evidence used to identify potentially better care practices that support newborn brain development.

STUDY DESIGN

Literature review.

RESULT

Sixteen potentially better practices are identified and grouped into two operational clinical bundles based upon timing for recommended implementation.

CONCLUSION

Existing evidence supports the implementation of selected care practices that potentially may support newborn brain development.

Is a nappy change stressful to neonates?

OBJECTIVES

Infants in neonatal intensive care (NICU infants) are often cared for in a stressful environment that includes potentially painful or stressful interventions. The aim was to investigate whether NICU infants have different pattern of stress and pain responses than healthy newborns when challenged by a non-painful everyday care routine.

METHODS

NICU infants born at 23-38 weeks gestation (n=39) were compared to healthy full-term newborns (n=30). Cortisol concentrations in saliva were determined before and 30 min after a standardised nappy change. The premature infant pain profile (PIPP) and the neonatal infant pain scale (NIPS) were evaluated before, during, directly after, 3 min after, and 30 min after the nappy change. The investigation was performed on two different occasions, first between postnatal days 2-7 and then between postnatal days 10-18.

RESULTS

NICU infants had higher median baseline salivary cortisol levels compared to full-term newborns on both occasions (17.1 nmol/L vs. 6.2 nmol/L p<0.01 and 8.5 nmol/L vs. 2.4 nmol/L p<0.01, respectively). Salivary cortisol decreased in response to the second nappy change in NICU infants (p=0.01). NICU infants had higher PIPP scores during both nappy changes (p<0.001 for both occasions) and more sustained increases in PIPP and NIPS up to 30 min after the nappy changes compared to full-term newborns.

CONCLUSIONS

NICU infants have higher baseline salivary cortisol than healthy full-term newborns. There is a change in baseline cortisol by age in both groups. Full-term infants as well as NICU infants show an increased pain response to a standardised nappy change.

Estimulação tátil-cinestésica: uma integração entre pele e sistema endócrino?

Apresenta-se uma revisão da literatura sobre os aspectos neuroendócrinos da pele e as conseqüências da estimulação tátil-cinestésica sobre o córtex adrenal. Os artigos foram identificados a partir das bases de dados MEDLINE e LILACS, usando as palavras-chave "córtex supra-renal", "pele", "massagem", "lactentes", "glicocorticóide" e "ritmo circadiano". O período pesquisado foi de 1990 a 2003. Foram também consultados artigos de destaque publicados antes desse período. Estudos reconhecem o hipotálamo, a hipófise e a glândula adrenal como órgãos dinâmicos durante o desenvolvimento fetal e neonatal, e que respostas de estresse estão presentes ao nascer. A maioria dos estudos revisados, utilizando a estimulação tátil-cinestésica, seja em humanos ou animais, evidencia a capacidade da pele em metabolizar, coordenar e organizar estímulos externos, procurando manter a homeostase interna e externa, demonstrando a interação entre sistema neuroendócrino e a pele. A estimulação tátil-cinestésica parece ter um efeito sobre a reatividade hormonal, porém essa questão merece uma investigação mais aprofundada.

A controlled trial of skin-to-skin contact in extremely preterm infants

BACKGROUND

Extremely preterm birth, even in the absence of significant neurological impairment, is associated with altered pain responses and impaired memory and behaviour. Preterm birth increases the risk of maternal depression and may impede the development of the mother-infant relationship, factors that in turn are also associated with impaired infant outcome. Mother-infant skin-to-skin contact has been recommended as a simple means of ameliorating these effects.

METHODS

We conducted a pragmatic, prospective, controlled, intention-to-treat trial in two neonatal intensive care units. Infants born below 32 weeks gestation were recruited within the first week after birth and assigned to a control group receiving standard care, or an intervention group in which mothers were encouraged to provide a session of skin-to-skin contact once daily for 4 weeks. We assessed infant behaviour at time of discharge from hospital, responses to immunisation at 4 and 12 months of age, and memory, behaviour and development at 1 year corrected (postmenstrual) age. Indices of maternal depression, stress, anxiety, lactation performance and infant interaction were assessed at time of infant discharge, 4 months and 1 year.

RESULTS

No significant difference was identified in any infant or maternal measure at any time point.

CONCLUSIONS

Mother-infant skin-to-skin contact after extremely preterm birth results in neither benefit nor adverse consequences. Although there is no reason to dissuade mothers who wish to provide STS contact, we are unable to recommend resource allocation for the implementation of STS programmes for extremely preterm infants in a neonatal intensive care unit setting.

Salivary cortisol and mood and pain profiles during skin-to-skin care for an unselected group of mothers and infants in neonatal intensive care

OBJECTIVES

Mother-infant separation after birth is a well-known source of stress. Parents and preterm infants in neonatal intensive care are separated immediately after birth. Skin-to-skin care is 1 possible method to reduce the separation-dependent stress. The aim of the present study was to investigate how skin-to-skin care influences stress for the mother and the infant in neonatal intensive care.

METHODS

Seventeen mother-infant pairs were included at their first and fourth skin-to-skin care. The infants were 25 to 33 weeks' gestational age, with birth weights ranging from 495 to 2590 g. In mothers, salivary cortisol, heart rate, mood scale, and stress measured on a visual analog scale (VAS) were analyzed. In infants, salivary cortisol and heart rate were analyzed, and because pain is one facet of stress, 2 different pain scales were used.

RESULTS

In mothers, the skin-to-skin care decreased salivary cortisol (32%), heart rate (7%), and VAS (89%), whereas mood increased (6%). Before the fourth skin-to-skin care, mothers rated less stress on VAS, and salivary cortisol and heart rate improved faster. The infants' cortisol either increased or decreased. Their heart rates and pain scores decreased during skin-to-skin care.

CONCLUSIONS

Our results lend additional support to the value of skin-to-skin care in neonatal intensive care. Variable stress responses in preterm infants favor the need for individualized care. The mothers' need for support seem to be more pronounced in the first skin-to-skin session as our results show a higher degree of stress as compared with later skin-to-skin care.