The effect of positioning on preterm infants' sleep-wake states and stress behaviours during exposure to environmental stressors

Visual stimulation in the neonatal intensive care unit: A systematic literature review

We aimed to systematically categorize evidence on the types of early visual stimulation applied to preterm infants (PTIs) admitted to neonatal intensive care units (NICUs), aiming to improve visual function parameters. This study was conducted according to PRISMA and registered in PROSPERO with CRD42022333753. Last search was conducted on March 15, 2023, in four different databases. Articles written in English, Portuguese, Spanish, or Italian, and available in full text were included. Two independent authors performed study selection, data extraction, and bias risk assessment. If there was any disagreement, a third author was contacted. A total of eight studies were included. From these, 62.5% presented a low risk of bias. 100% used a multisensory intervention, which included visual stimulation. In 50%, visual intervention consisted of black and white stimulation cards placed inside the incubator for three minutes. The outcomes showed positive benefits in visual function parameters and other reported clinical benefits in breastfeeding and neuromuscular development. This review demonstrated there is still scarce literature on the effects of early visual stimulation on purely visual functional outcomes, although the existing findings are promising. Parental involvement has been generating unquestionable benefits for the binomial mother-infant and gaining greater acceptance by health professionals.

The effect of M technique massage on behavioral state and weight gain in preterm neonates: A randomized controlled trial

This study aimed to investigate the effect of M technique massage on behavioral state and weight gain in preterm neonates admitted to neonatal intensive care unit (NICU). This was a randomized controlled trial study in which a total of 64 preterm neonates were randomly allocated to intervention and control group. Intervention group received M technique massage and control group received routine care. Neonatal weight and behavioral state were measured for two weeks. After intervention, no statistically significant difference was found between groups in terms of neonatal weight (mean difference: 44.03, 95% CI [-180.66, 268.74]). At baseline, the mean score for behavioral state response was 5.84 ± 2.20 (mean ± SD) in control group and 5.68 ± 2.15 (mean ± SD) in intervention group and the difference was not significant (mean difference: 0.16, 95% CI [-1.21, 1.52]), but 2 weeks later, and also, after intervention, a statistically significant difference was found between groups (mean difference: 2.16, 95% CI [1.19, 3.17]) and (mean difference: 3.03, 95% CI [2.15, 3.91]), respectively, meaning that it was significantly lower in intervention group compared with control group. According to the findings, massage with M technique in premature neonates can have a positive effect on behavioral state, but no effect on their weight gain.

Systematic Review of the Effects of Positioning on Nonautonomic Outcomes in Preterm Infants

OBJECTIVE

To identify and synthesize the available evidence on the effect of different positions (prone, supine, and right and left lateral) on nonautonomic outcomes for preterm infants admitted to the NICU.

DATA SOURCES

We searched the CINAHL, MEDLINE, Scopus, and Cochrane databases for reports of primary research studies using a three-step strategy. We also searched for gray literature and reviewed the reference lists of retrieved articles.

STUDY SELECTION

We included reports of quantitative studies published in English from database inception through February 2022 that focused on positioning and nonautonomic outcomes (pain, comfort, skin integrity, behavioral state, and sleep quality and duration) for preterm infants in the NICU. Two authors independently screened titles and abstracts and assessed articles in full text against the inclusion criteria.

DATA EXTRACTION

Two authors independently extracted the data from the full-text articles using a standardized data extraction tool. We synthesized the data narratively because of the different designs and outcome measures among the included studies.

DATA SYNTHESIS

From a total of 550 records initially screened, we included 17 articles in our review. In the included articles, prone positioning improved sleep quality and duration, whereas supine positioning was associated with increased awakenings and activity. Infants demonstrated fewer self-regulatory behaviors in the prone position compared to supine or side-lying and were less stressed in the prone position. We found minimal evidence on the effect of positioning on skin integrity or pain.

CONCLUSION

There is limited good-quality evidence on the effect of positioning on nonautonomic outcomes in preterm infants. To inform clinical practice, high-quality randomized controlled trials focused on the positioning of premature infants are warranted.

Parent-infant skin-to-skin contact reduces the electrical activity of the diaphragm and stabilizes respiratory function in preterm infants

BACKGROUND

The physiological benefit of parent-infant skin-to-skin contact (SSC) is uncertain for preterm infants with ventilatory support. We aimed to investigate whether SSC stabilizes the respiration compared to incubator care in mechanically ventilated preterm infants.

METHODS

The prospective observational study was performed in Turku University Hospital, Finland. Preterm infants were eligible if they were born before 36 weeks gestation and received respiratory support with either invasive or non-invasive neurally adjusted ventilatory assist (NAVA). SSC was applied as soon as possible after birth. Respiratory variables were collected from the ventilator log data, and SSC episodes were compared with matched control periods during incubator care.

RESULTS

A total of 167 episodes of SSC were recorded from 17 preterm infants: 138 episodes during invasive NAVA and 29 episodes during non-invasive NAVA. During invasive NAVA, peak electrical activity of the diaphragm (Edi), minimum Edi, respiratory rate, time on backup ventilation, peak inspiratory pressure, and mean airway pressure were significantly lower in SSC than in incubator care. During non-invasive NAVA, peak Edi, minimum Edi, time on backup ventilation, and peak inspiratory pressure were significantly lower in SSC than in incubator care.

CONCLUSIONS

SSC stabilized and improved the respiratory physiology in mechanically ventilated preterm infants.

IMPACT

Skin-to-skin contact reduced work of breathing compared to incubator care in mechanically ventilated preterm infants. Skin-to-skin contact reduced the need for backup ventilation during neurally adjusted ventilatory assist in preterm infants. Skin-to-skin contact among ventilated preterm infants was not only safe but also stabilized and improved their respiratory physiology.

Transition to a Safe Home Sleep Environment for the NICU Patient

Of the nearly 3.8 million infants born in the United States in 2018, 8.3% had low birth weight (<2500 g [5.5 lb]) and 10% were born preterm (gestational age of <37 completed weeks). Many of these infants and others with congenital anomalies, perinatally acquired infections, and other disease require admission to a NICU. In the past decade, admission rates to NICUs have been increasing; it is estimated that between 10% and 15% of infants will spend time in a NICU, representing approximately 500 000 neonates annually. Approximately 3600 infants die annually in the United States from sleep-related deaths, including sudden infant death syndrome International Classification of Diseases, 10th Revision (R95), ill-defined deaths (R99), and accidental suffocation and strangulation in bed (W75). Preterm and low birth weight infants are particularly vulnerable, with an incidence of death 2 to 3 times greater than healthy term infants. Thus, it is important for health care professionals to prepare families to maintain their infant in a safe sleep environment, as per the recommendations of the American Academy of Pediatrics. However, infants in the NICU setting commonly require care that is inconsistent with infant sleep safety recommendations. The conflicting needs of the NICU infant with the necessity to provide a safe sleep environment before hospital discharge can create confusion for providers and distress for families. This technical report is intended to assist in the establishment of appropriate NICU protocols to achieve a consistent approach to transitioning NICU infants to a safe sleep environment as soon as medically possible, well before hospital discharge.

Effects of two different positions on stress, pain and feeding tolerance of preterm infants during tube feeding

AIMS

This study aims to investigate the effects of semi-elevated right lateral and semi-elevated supine positions on feeding tolerance, stress severity and pain levels among premature infants during tube feeding.

METHODS

This was a randomized cross-over clinical trial. A total of 34 premature infants who were fed via orogastric tube were included in this study. Feeding tolerance was assessed by abdominal circumference measurements and checking gastric residuals; this assessment was single blinded. Physiological values were evaluated before, during and after tube feeding. The stress severity and pain levels of the infants were also evaluated independently by the researchers before, during and after tube feeding. A significance level of .05 was accepted for all statistical analyses.

RESULTS

There were no difference between infants' vital signs, stress and pain scores according to feeding positions before tube feeding (p > .05). By feeding positions, a statistically significant difference was found between infants' vital signs, abdominal circumference and gastric residuals of infants during tube feeding. Pain and stress levels of infants were found to be significantly higher in the semi-elevated supine position during tube feeding (p < .05).

CONCLUSIONS

Use of the semi-elevated right lateral position during tube feeding was found to have a more helpful effect in reducing stress and pain among premature infants when compared with the use of the semi-elevated supine position.

Effect of Body Position on Cardiorespiratory Stabilization and Comfort in Preterm Infants on Continuous Positive Airway Pressure

PURPOSE

The purpose of the study is to investigate the effect of four body positions (supine, prone, left lateral, right lateral) on cardiorespiratory stabilization and comfort in preterm infants receiving Nasal Continuous Positive Airway Pressure (NCPAP).

DESIGN AND METHODS

In the study conducted as a randomized crossover design, the sample was composed of 20 preterm infants receiving NCPAP therapy. At each change of position, the baby was allowed to stabilize for 15 min, and heart rate and oxygen saturation values were recorded every 10 min for the next 60 min. The comfort levels of the infants in each position were evaluated at 30th and 60th minutes using the Premature Infant Comfort Scale.

RESULTS

At the end of the study, it was determined that there was no statistically significant difference between heart rate (p = .83), respiratory rate (p = .90) and oxygen saturation (p = .15) of the infants in terms of their positions. When the mean comfort scores of the preterm infants were compared in terms of position, it was found that there was a difference between the positions (p < .01). According to the scale evaluation, the highest comfort level of the infants was in the prone position, which was followed by right lateral, supine and left lateral positions.

PRACTICE IMPLICATIONS

Prone position was the most comfortable for preterm infants. However, comfort levels of preterm infants were also high enough in other positions so that no intervention is needed. In order to ensure comfort and cardiorespiratory stabilization, any of the four body positions can be chosen.

Autonomic responses of premature newborns to body position and environmental noise in the neonatal intensive care unit

Objective

Evaluate the physiological and autonomic nervous system responses of premature newborns to body position and noise in the neonatal intensive care unit.

Methods

A quasi-experimental study. The autonomic nervous system of newborns was evaluated based on heart rate variability when the newborns were exposed to environmental noise and placed in different positions: supine without support, supine with manual restraint and prone.

Results

Fifty premature newborns were evaluated (gestational age: 32.6 ± 2.3 weeks; weight: 1816 ± 493g; and Brazelton sleep/awake level: 3 to 4). A positive correlation was found between environmental noise and sympathetic activity (R = 0.27, p = 0.04). The mean environmental noise was 53 ± 14dB. The heart rate was higher in the supine position than in the manual restraint and prone positions (148.7 ± 21.6, 141.9 ± 16 and 144 ± 13, respectively) (p = 0.001). Sympathetic activity, represented by a low frequency index, was higher in the supine position (p < 0.05) than in the other positions, and parasympathetic activity (high frequency, root mean square of the sum of differences between normal adjacent mean R-R interval and percentage of adjacent iRR that differed by more than 50ms) was higher in the prone position (p < 0.05) than in the other positions. The complexity of the autonomic adjustments (approximate entropy and sample entropy) was lower in the supine position than in the other positions.

Conclusion

The prone position and manual restraint position increased both parasympathetic activity and the complexity of autonomic adjustments in comparison to the supine position, even in the presence of higher environmental noise than the recommended level, which tends to increase sympathetic activity.

Sleep and prematurity: sleep outcomes in preterm children and influencing factors

BACKGROUND

Sleep undergoes changes from birth to adulthood, while sleep disorders are associated with various cognitive deficiencies in childhood. In parallel, prematurity is known to predispose to poor neurodevelopmental outcomes. Our aim is to provide literature data about factors influencing sleep in the premature infants and sleep outcomes in this population.

METHODS

A systematic review was conducted using a variety of health-related databases. Original research papers were considered and no year-of-publication restriction was placed.

RESULTS

In total, 22 articles fulfilled our selection criteria. Available studies present remarkable heterogeneity in terms of methodological design. Compared to full term, premature infants exhibit significant differences in sleep structure, which mainly include differences in electroencephalographic spectral values, in total sleep time and in arousal threshold. Furthermore, prematurity seems to be a risk factor of sleep breathing disorders in childhood and adolescence. Data about the effect of methylxanthines and the environment of neonatal intensive care unit is controversial. With regard to the impact of prematurity-related sleep disorders on future neurodevelopment, available research papers are generally few.

CONCLUSIONS

The alterations in sleep patterns are an outcome of prematurity (immaturity of nervous system) as well as of postnatal factors and comorbidities. Sleep problems in this population of infants seems to be a missing piece of the puzzle of impaired neurodevelopment. Future studies should focus on interventions to improve sleep hygiene and limit neurodevelopmental problems.

Does the Post-Feeding Position Affect Gastric Residue in Preterm Infants?

BACKGROUND

Body position affects the gastric emptying rate and hence the amount of gastric residue.

OBJECTIVE

This study aims to analyze the effect of the post-feeding position of preterm infants on gastric residue.

MATERIALS AND METHODS

This experimental study was conducted in the neonatal intensive care unit (NICU) of a university hospital (İnönü University Turgut Özal Medical Center) in Eastern Turkey. The study included 40 preterm infants weighing less than 2,000 g, who were fed orogastrically. The preterm infants were sequentially placed in four positions and were fed before each change of position. The infants were sequentially placed in the right lateral, left lateral, supine, and prone positions; their gastric residues were measured with a nasogastric tube. The gastric residue was recorded in percentages at 30, 60, 120, and 180 minutes. Ethical principles were applied in all phases of the study.

RESULTS

The lowest mean gastric residue level was observed in the right lateral position at 30 minutes (58.16 ± 12.71%) and 60 minutes (33.97 ± 15.00%). The prone position showed the lowest mean gastric residue level (1.74 ± 1.08%), followed by the right lateral (3.06 ± 1.97%), supine (3.53 ± 2.18%), and left lateral position (5.14 ± 1.85%) at 120 minutes. The final measurements were taken at 180 minutes with the right lateral position showing the lowest mean gastric residue level (0.38 ± 0.34%).

CONCLUSION

The premature infants had similar lower levels of gastric residue in the right lateral and prone positions and higher levels of gastric residue in left lateral and supine positions. The gastric emptying rate was found to be highest in the right lateral position at 30, 60, and 180 minutes and in the prone position at 120 minutes.

Body positioning for spontaneously breathing preterm infants with apnoea

BACKGROUND

It has been proposed that body positioning in preterm infants, as compared with other, more invasive measures, may be an effective method of reducing clinically significant apnoea.

OBJECTIVES

To determine effects of body positioning on cardiorespiratory parameters in spontaneously breathing preterm infants with clinically significant apnoea.Subgroup analyses examined effects of body positioning of spontaneously breathing preterm infants with apnoea from the following subgroups.• Gestational age < 28 weeks or birth weight less than 1000 grams.• Apnoea managed with methylxanthines.• Frequent apnoea (> 10 events/d).• Type of apnoea measured (central vs mixed vs obstructive)

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group (CNRG) to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 10), MEDLINE via PubMed (1966 to 14 November 2016), Embase (1980 to 14 November 2016) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 2016 November 14). We also searched clinical trials databases and conference proceedings for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled clinical trials with parallel, factorial or cross-over design comparing the impact of different body positions on apnoea in spontaneously breathing preterm infants were eligible for our review.

DATA COLLECTION AND ANALYSIS

We assessed trial quality, data extraction and synthesis of data using standard methods of the CNRG. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the quality of evidence.

MAIN RESULTS

The search conducted in November 2016 identified no new studies. Five studies (N = 114) were eligible for inclusion. None of the individual studies nor meta-analyses showed a reduction in apnoea, bradycardia, oxygen desaturation or oxygen saturation with body positioning (supine vs prone; prone vs right lateral; prone vs left lateral; right lateral vs left lateral; prone horizontal vs prone head elevated; right lateral horizontal vs right lateral head elevated, left lateral horizontal vs left lateral head elevated).

AUTHORS' CONCLUSIONS

We found insufficient evidence to determine effects of body positioning on apnoea, bradycardia and oxygen saturation in preterm infants. No new studies have been conducted since the original review was published. Large, multi-centre studies are warranted to provide conclusive evidence, but it may be plausible to conclude that positioning of spontaneously breathing preterm infants has no effect on their cardiorespiratory parameters.