Validation of Actiwatch for Assessment of Sleep-wake States in Preterm Infants

The Effects of a Three-Stair Positioning Pillow Used for Preterm Infants on Physiologic Parameters and Sleep-Wakefulness Status: Randomized Controlled Trial

BACKGROUND

It is important to provide the necessary sleep for the growth of preterm infants in the neonatal intensive care unit. The purpose of this study was to determine the effect of 3-stair positioning pillows (TSPPs) developed for preterm infants with postnatal age 28 to 35 weeks on physiologic parameters and sleep-wakefulness status.

METHODS

This research was conducted as a randomized controlled experimental study. The CONSORT flowchart was used in the implementation of the randomized controlled trial. The preterm infants in the experimental group were placed in the prone position with TSPPs, whereas the preterm infants in the control group were followed in the routine prone position given in the neonatal intensive care unit. Preterm infants were followed for a total of 3 hours.

RESULTS

The sample of the study consisted of 60 preterm infants (experiment group = 30; control group = 30) who were hospitalized in the neonatal intensive care unit and met the selection criteria. Compared with the infants in the control group, the preterm infants in the experimental group were determined to have significantly lower heart rates, higher oxygen saturations, lower respiratory rates, longer sleep durations, and shorter wakefulness times (P < .001).

CONCLUSION

It was found that positioning preterm infants using TSPP had positive effects on physiological parameters (heart rate, oxygen saturation, and respiratory rate) and sleep-wakefulness status in favor of the experimental group.

IMPLICATIONS FOR PRACTICE

It is recommended to use a TSPP that supports the prone position to improve the physiologic parameters and sleep-wakefulness status of preterm infants in the neonatal intensive care unit. Larger studies need to be conducted utilizing longer follow-up protocols. Examining the effectiveness of TSPPs with different positioning materials in preterm infants is needed.

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.

Effects of caffeine therapy for apnea of prematurity on sleep and neurodevelopment of preterm infants at 6 months of corrected age

STUDY OBJECTIVES

To determine the differences in sleep patterns between preterm infants who received caffeine and those who did not and to evaluate the effects of caffeine therapy on early neurodevelopment. Secondarily, actigraphy and polysomnography were compared to evaluate the sleep of preterm infants.

METHODS

Twenty-eight preterm infants ages 28-34 weeks admitted to a single-center Level III neonatal intensive care unit between May 2020 and May 2021 were included. Sleep was assessed by actigraphy for 72 hours with Respironics Mini-Mitter® Actiwatch-2 and Brief Infant Sleep Questionnaire at 6 months corrected age. On the first day of actigraphy, infants underwent polysomnography between 10:00 am and 3:00 pm. Neurodevelopment was evaluated by the Bayley Scales of Infant and Toddler Development-III, the Ages & Stages Questionnaire, and the Hammersmith Infant Neurological Examination.

RESULTS

There were no significant differences in sleep parameters measured by actigraphy, the Brief Infant Sleep Questionnaire, and polysomnography between infants in the caffeine group (n = 12) and no-caffeine group (n = 16). Sensitivity (91.07%) and agreement rate (77.21%) for the actigraphy against polysomnography were highest at the automatic threshold. No significant differences were observed in the neurodevelopment of infants in the caffeine group compared to the no-caffeine group.

CONCLUSIONS

Sleep parameters and neurodevelopmental outcomes were not different in infants at 6 months of corrected age with regard to caffeine therapy. Actigraphy at the automatic threshold can be used in infants for sleep pattern assessment.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Influence of Caffeine Therapy in Preterm Infants; URL: https://www.clinicaltrials.gov/ct2/show/NCT04376749; Identifier: NCT04376749.

CITATION

Atalah YEY, Barış HE, Akdere SK, et al. Effects of caffeine therapy for apnea of prematurity on sleep and neurodevelopment of preterm infants at 6 months of corrected age. J Clin Sleep Med. 2023;19(12):2075-2085.

Multisensory stimulation bundles on sleep and neurobehavioral development in the first year after birth in very preterm infants: a randomized crossover controlled study protocol

BACKGROUND

Disrupted sleep is believed to contribute to short- and long-term neurodevelopmental problems in very preterm infants (VPIs). This study presents a protocol for an evaluator-blinded, randomized crossover trial. It aims to assess the sleep efficiency of hospitalized VPIs by providing multisensory stimulation bundles. Furthermore, it aims to observe the intervention impacts on sleep during hospitalization of the VPIs and their sleep and neurodevelopmental outcomes during the first year of post-discharge follow-up.

METHODS

The study will be conducted in the neonatology department of a tertiary pediatric teaching hospital. All the eligible VPIs will undergo two types of care in random order: "standard care" (2 weeks) and "standard care plus multisensory stimulation bundles," each lasting 2 weeks. A generated list of random numbers will be used for case sequence allocation. Sleep outcomes will be evaluated using the Actiwatch-2 Actigraph. Moreover, the amplitude-integrated electroencephalography and the Griffiths Mental Development Scales will be used to measure the neurodevelopmental outcomes during hospitalization and in the first year of follow-up of the VPIs.

DISCUSSION

The intervention protocol of this study differs from that of other traditional interventions by producing precise and consistent supportive stimulations, similar to maternal tactile, auditory, posture, and visual effects for hospitalized VPIs. This protocol could be an effective measure to facilitate sleep and early neurodevelopment of VPIs. The expected outcomes will help confirm the implementation and generalization of the multisensory stimulation bundles' care protocol in neonatology departments. We expect that the study will positively impact hospitalized VPIs, especially in their sleep and early neurodevelopmental outcomes. It will also provide a new perspective regarding parent and infant interaction strategies, particularly for newborn intensive care units that limit visits because of the global spread of COVID-19.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR 2200059099. Registered on 25 April 2022, https://www.chictr.org.cn/showproj.html?proj=166980 ; the Hospital Research Ethics Committee (approval number: SCMCIRB-K2021086-1, Version 01), approved on 21 January 2022.

Continuous sensing and quantification of body motion in infants: A systematic review

Abnormal body motion in infants may be associated with neurodevelopmental delay or critical illness. In contrast to continuous patient monitoring of the basic vitals, the body motion of infants is only determined by discrete periodic clinical observations of caregivers, leaving the infants unattended for observation for a longer time. One step to fill this gap is to introduce and compare different sensing technologies that are suitable for continuous infant body motion quantification. Therefore, we conducted this systematic review for infant body motion quantification based on the PRISMA method (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). In this systematic review, we introduce and compare several sensing technologies with motion quantification in different clinical applications. We discuss the pros and cons of each sensing technology for motion quantification. Additionally, we highlight the clinical value and prospects of infant motion monitoring. Finally, we provide suggestions with specific needs in clinical practice, which can be referred by clinical users for their implementation. Our findings suggest that motion quantification can improve the performance of vital sign monitoring, and can provide clinical value to the diagnosis of complications in infants.

Sleep assessment in preterm infants: Use of actigraphy and aEEG

OBJECTIVE

Objective methods to monitor the sleep of preterm infants at the neonatal intensive care unit (NICU) are required to prevent potentially adverse neurodevelopmental outcomes. This study aimed to determine the concordance of actigraphy and amplitude-integrated electroencephalogram (aEEG) against gold standard direct observation (DO) in assessing sleep/wake states of typically developing preterm infants.

METHODS

This prospective observational study was conducted in a single center level III NICU. Sleep variables were measured using Philips Respironics Mini-Mitter® Actiwatch-2 for 24 h and compared with 8-h matched data of aEEG and DO. Sensitivity-specificity analysis, Cohen's kappa, prevalence-adjusted and bias-adjusted kappa (PABAK), and Bland Altman plots were generated.

RESULTS

Seventeen preterm infants were recruited. A total of 11252 epochs were studied. Sensitivity (86.4%), agreement rate (67.9%), and predictive value for wake (47.9%) for the actigraphy were highest at the automatic activity threshold whereas specificity (54.5%) and predictive value for sleep (75.5%) were highest at low threshold. The sensitivity of aEEG was 79.3% and the specificity was 54.3%. At all thresholds, the agreement was largely equivalent with low kappas (0.14-0.17) and PABAK coefficients (0.22-0.35) for actigraphy and DO. Moderate agreement was observed between aEEG and DO according to the PABAK coefficient (0.44). Mean differences in sleep parameters were not different between DO and aEEG as well as DO/aEEG and actigraphy at medium threshold (p > 0.05).

CONCLUSIONS

Actigraphy at medium threshold can be used in depicting sleep in typically developing preterm infants at NICU. aEEG may be an alternative adjunctive method to actigraphy for the evaluation of sleep/wake states in the NICU setting.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04145362.

Actigraphy: Metrics reveal it is not a valid tool for determining sleep in neonates

Study of emerging sleep-wake patterns in neonates is important for promptly identifying and treating abnormal sleep behaviours to ensure healthy infant development and neurobehavioral outcomes. Current methods to assess sleep are costly, labour intensive, and particularly difficult to implement in fragile, hospitalised infants requiring intensive medical care. The aim of the present study was to assess the validity of actigraphy as a tool for detecting sleep in preterm infants, using polysomnography (PSG) as the "gold standard". A total of 10 neonates (mean [SD] 35.8 [1.2] weeks post-menstrual age; five female) hospitalised since birth for prematurity each participated in one 8-10 hr session during which PSG and actigraphy were recorded simultaneously. Inter-feed minute-by-minute PSG Sleep-Wake scores were compared to concurrent actigraph epochs categorised as either "Sleep" or "Wake" using three separate movement-per-minute thresholds (≤20, ≤40, ≤80). Tool validity was assessed using five metrics. A key finding was that for each of the movement thresholds there was high agreement rate, sensitivity, and predictive value of sleep (85.2%-97.2%), whereas specificity and predictive value of wake remained low (12%-46%). Receiver operating characteristic curve analysis also revealed low discriminatory power of actigraphy for estimating sleep (area under the curve = 0.636; Youden's Index J = 0.2173). Lack of sufficient minutes of autonomous wake periods among infants was identified as a key limitation in actigraphy. Findings from the present study suggest actigraphy cannot be validated for Sleep/Wake discrimination in preterm infants and that proper validation requires sufficient data from periods of both Sleep and Wake.

Video-based neonatal state assessment method for timing of procedures

BACKGROUND

Procedures should be performed when an infant is most receptive to disruptions in order to reduce the stress on the infant. However, frequent direct observations place a heavy burden on medical staff. There is therefore a need for a method for quantitatively and automatically evaluating the neonatal state.

METHODS

Ten infants in our hospital were enrolled in this study. The states of the infants were assessed by medical staff using the Brazelton Neonatal Behavioral Assessment Scale and were recorded on video at the same time. The recorded states were reclassified as activity levels, a new state classification method that includes middle activity, which is the appropriate time for a procedure. Using image analysis, motions of the infant were quantified as two indices: activity and pause time. Activity and pause time were compared for each activity level. The cutoff values of the indices were calculated, and the sensitivity and specificity of the middle activity were calculated.

RESULTS

There was a significant difference between all groups of activity level (P < 0.01). The maximum sensitivity and specificity of middle activity were 71.7% and 51.2%, respectively.

CONCLUSIONS

The neonatal state of infants can be quantitatively and automatically evaluated using video cameras, and the activity level can be used to determine an appropriate time for procedures in infants. This will reduce the burden on medical staff and lead to less stressful procedures for infants.

Intra- and Inter-Model Variability of Light Detection Using a Commercially Available Light Sensor

The veracity of claims made by researchers and clinicians when reporting the impact of lighting on vision and other biological mechanisms is, in part, reliant on accurate and valid measurement devices. We aim to quantify the intra- and inter-watch variability of a commercially available light sensor device which has been widely used in vision and other photobiological research. Intra- and inter-watch differences were investigated between four Actiwatch Spectrum Pro devices. The devices were used to obtain measurements on two separate occasions, under three different controlled light conditions; the Gretag Macbeth Judge II lightbox was used to produce Simulated Daylight (D65), Illuminant A (A) and Cool White Fluorescent (CWF) lighting. Significant inter-watch differences were noted when considering tricolour (red, green, blue) and the white sensor outputs under each of the three illuminants (p < 0.01). A significant interaction was also found between tricolour sensor and watch used (p < 0.01). Intra-watch differences were noted for the tricolour and for the white sensor outputs under the three illuminants (≤0.05), for all but one watch which showed no significant intra-watch difference for the white 'sensor output' under the D65 illuminant. Use of spectral sensitivity devices is an evolving field. Before drawing causal relationships between light and other biological processes, researchers should acknowledge the limitations of the instruments used, their validation, and the resultant data. The outcomes of the study indicate caution must be exercised in longitudinal data collection and the mixing of watches amongst study participants should be avoided.

A novel machine learning unsupervised algorithm for sleep/wake identification using actigraphy

Actigraphy is widely used in sleep studies but lacks a universal unsupervised algorithm for sleep/wake identification. An unsupervised algorithm is useful in large-scale population studies and in cases where polysomnography (PSG) is unavailable, as it does not require sleep outcome labels to train the model but utilizes information solely contained in actigraphy to learn sleep and wake characteristics and separate the two states. In this study, we proposed a machine learning unsupervised algorithm based on the Hidden Markov Model (HMM) for sleep/wake identification. The proposed algorithm is also an individualized approach that takes into account individual variabilities and analyzes each individual actigraphy profile separately to infer sleep and wake states. We used Actiwatch and PSG data from 43 individuals in the Multi-Ethnic Study of Atherosclerosis study to evaluate the method performance. Epoch-by-epoch comparisons and sleep variable comparisons were made between our algorithm, the unsupervised algorithm embedded in the Actiwatch software (AS), and the pre-trained supervised UCSD algorithm. Using PSG as the reference, the accuracy was 85.7% for HMM, 84.7% for AS, and 85.0% for UCSD. The sensitivity was 99.3%, 99.7%, and 98.9% for HMM, AS, and UCSD, respectively, and the specificity was 36.4%, 30.0%, and 31.7%, respectively. The Kappa statistic was 0.446 for HMM, 0.399 for AS, and 0.311 for UCSD, suggesting fair to moderate agreement between PSG and actigraphy. The Bland-Altman plots further show that the total sleep time, sleep latency, and sleep efficiency estimates by HMM were closer to PSG with narrower 95% limits of agreement than AS and UCSD. All three methods tend to overestimate sleep and underestimate wake compared to PSG. Our HMM approach is also able to differentiate relatively active and sedentary individuals by quantifying variabilities in activity counts: individuals with higher estimated activity variabilities tend to show more frequent sedentary behaviors. Our unsupervised data-driven HMM algorithm achieved better performance than the commonly used Actiwatch software algorithm and the pre-trained UCSD algorithm. HMM can help expand the application of actigraphy in cases where PSG is hard to acquire and supervised methods cannot be trained. In addition, the estimated HMM parameters can characterize individual activity patterns and sedentary tendencies that can be further utilized in downstream analysis.

Effects of a supportive care bundle on sleep variables of preterm infants during hospitalization

Sleep is important for preterm infants' brain development, but they are frequently exposed to painful procedures in the neonatal intensive care unit (NICU) that disturb their sleep cycle and affect their growth. The purpose of this study was to examine the prolonged effects of a supportive care bundle (modulation of the infants' states, non-nutritive sucking, facilitated tucking, and oral sucrose feeding) on preterm infants' sleep variables (sleep efficiency, total sleep time, sleep latency, and frequency of wake bouts) during hospitalization. The team recruited 65 preterm infants (gestational age at birth 28-36 weeks, average birth weight 1,652 g) from a Level III NICU at a medical center in Taiwan. Infants were randomly assigned to one of two treatment conditions to be administered while receiving intrusive procedures: (1) control condition (usual care, including routine procedures, positioning, and gentle touch); or (2) intervention condition in which the supportive care bundle was added to usual care. Sleep variables were measured using actigraphy for a baseline of three continuous days on the 6th to 8th days after birth and again for 3 continuous days when infants weighed ≧1,950 g. Two forms of generalized estimating equation analyses with control of significant covariates were used for data analysis. The supportive care bundle not only significantly increased sleep efficiency and total sleep time but also significantly decreased duration of sleep latency and frequency of wake bouts. These results provide evidence to support the incorporation of the supportive care bundle into NICU clinical practice during intrusive procedures.

Factors Associated With Preterm Infants’ Circadian Sleep/Wake Patterns at the Hospital

This prospective repeated-measures study explored potential factors (postmenstrual age, body weight, gender, chronological age, illness severity, and circadian rhythm) related to preterm infants’ circadian sleep/wake patterns. Circadian sleep/wake patterns were measured using an Actiwatch for 3 continuous days in preterm infants (gestational age of 28-36.4 weeks) in a neonatal intensive care unit and hospital nursery. Potential factors associated with circadian sleep/wake patterns were analyzed using the generalized estimating equation. For our sample of 30 preterm infants, better sleep/wake patterns were associated with male gender, younger postmenstrual and chronological age, lower body weight, and less illness severity. Preterm infants’ total sleep time ( B = 41.828, p < .01) and percentage of sleep time ( B = 3.711, p < .01) were significantly longer at night than during the day. These findings can help clinicians recognize preterm infants’ sleep problems, signaling the need to provide individualized support to maintain these infants’ sleep quality during their early life.