An electroencephalography-based sleep index and supervised machine learning as a suitable tool for automated sleep classification in children.

STUDY OBJECTIVES: Although sleep is frequently disrupted in the pediatric intensive care unit, it is currently not possible to perform real-time sleep monitoring at the bedside. In this study, spectral band powers of electroencephalography data are used to derive a simple index for sleep classification. METHODS: Retrospective study at Erasmus MC Sophia Children's Hospital, using hospital-based polysomnography recordings obtained in non-critically ill children between 2017 and 2021. Six age categories were defined: 6-12 months, 1-3 years, 3-5 years, 5-9 years, 9-13 years, and 13-18 years. Candidate index measures were derived by calculating spectral band powers in different frequent frequency bands of smoothed electroencephalography. With the best performing index, sleep classification models were developed for two, three, and four states via decision tree and five-fold nested cross-validation. Model performance was assessed across age categories and electroencephalography channels. RESULTS: In total 90 patients with polysomnography were included, with a mean (standard deviation) recording length of 10.3 (1.1) hours. The best performance was obtained with the gamma to delta spectral power ratio of the F4-A1 and F3-A1 channels with smoothing. Balanced accuracy was 0.88, 0.74, and 0.57 for two-, three-, and four-state classification. Across age categories, balanced accuracy ranged between 0.83 and 0.92 and 0.72 and 0.77 for two- and three-state classification, respectively. CONCLUSIONS: We propose an interpretable and generalizable sleep index derived from single-channel electroencephalography for automated sleep monitoring at the bedside in non-critically ill children ages 6 months to 18 years, with good performance for two- and three-state classification. CITATION: van Twist E, Hiemstra FW, Cramer ABG, et al. An electroencephalography-based sleep index and supervised machine learning as a suitable tool for automated sleep classification in children. J Clin Sleep Med. 2024;20(3):389-397.

Intermittent feeding with an overnight fast versus 24-h feeding in critically ill neonates, infants, and children: An open-label, single-centre, randomised controlled trial.

BACKGROUND & AIMS: Critically ill children are fed day and night, assuming this improves enteral tolerance and the probability of achieving nutritional goals. It was previously shown that a fasting response, reflected by increased ketosis, at least partly explained the beneficial outcome of delayed initiation of supplemental parenteral nutrition. This study aims to investigate whether an overnight fast increases ketosis and is feasible and safe in critically ill children. METHODS: The Continuousversus Intermittent Nutrition in Paediatric Intensive Care (ContInNuPIC) study is a randomised controlled trial in a tertiary referral Paediatric Intensive Care Unit (PICU) in the Netherlands. Critically ill children (term newborn-18 years) with an expected PICU stay ≥48 h, dependent on artificial nutrition, were eligible. Participants were randomly assigned (1:1, stratified for age group) to intermittent feeding, with interruption of feedings during an age-dependent overnight period of eight to 12 h, or to continuous feeding, with the administration of feedings day and night. In both groups, similar daily caloric targets were pursued. For children younger than one year, mandatory minor glucose infusions were provided during fasting. The primary outcome was the feasibility, defined as two conditions (1): a significant difference in the patients' highest daily ketone (3-ß-hydroxybutyrate, BHB) levels during each overnight period, and (2): non-inferiority regarding daily caloric intake, examined using a two-part mixed-effects model with a predefined non-inferiority margin of 33%, in an intention-to-treat analysis. The study is registered in the Netherlands Trial Register (NL7877). RESULTS: Between May 19, 2020, and July 13, 2022, 140 critically ill children, median (first quartile; third quartile) age 0.3 (0.1; 2.7) years, were randomised to intermittent (n = 67) or continuous feeding (n = 73). In the intermittent feeding group, BHB levels were significantly higher (median 0.4 (0.2; 1.0) vs. 0.3 (0.1; 0.7) mmol/L, p < 0.001). The ratio of total caloric intake in the intermittent feeding group to the intake in the continuous feeding group was not consistently significantly more than 0.67, thus not proving non-inferiority. No severe, resistant hypoglycaemic events, nor severe gastrointestinal complications related to the intervention occurred, and feeding intolerance did not occur more often in the intermittent than in the continuous feeding group. CONCLUSION: Compared with day and night feeding, intermittent feeding with an overnight fast and mandatory glucose infusion for children younger than one year marginally increased ketosis and did not lead to more hypoglycaemic incidents in critically ill children. Because non-inferiority regarding daily caloric intake was not proven, the feasibility of an overnight fast could not be shown in the current study. However, as feeding intolerance did not increase during the condensed feeding periods, the nutritional intake was probably limited by the prescription of nutrition and interruptions. More research is needed to determine the optimal level and duration of clinically relevant ketosis and the best method to achieve this.

Continuous Versus Intermittent Nutrition in Pediatric Intensive Care Patients: Protocol for a Randomized Controlled Trial.

BACKGROUND: Intermittent fasting is a time-restricted feeding strategy with proven health benefits, which is based on multiple metabolic and endocrine changes, in several patient populations and healthy participants. In the pediatric intensive care unit (PICU), artificial feeding is usually administered 24 hours a day, although solid evidence supporting this practice is lacking. This discards the potential benefits of fasting in this population. We hypothesize that intermittent nutrition with a focus on an overnight feeding interruption (intermittent fasting), as compared with 24-hour continuous nutrition, is a feasible and safe strategy, with potential benefits, for critically ill children. OBJECTIVE: The aim of the Continuous versus Intermittent Nutrition in Pediatric Intensive Care randomized controlled trial (RCT) is to investigate a strategy of intermittent nutrition with a focus on an overnight feeding interruption period versus 24-hour nutrition during the first 14 days in the PICU. METHODS: The Continuous versus Intermittent Nutrition in Pediatric Intensive Care study is an investigator-initiated RCT in a tertiary referral PICU. Critically ill children (term newborn to 18 years), expected to stay in the PICU for ≥48 hours, and dependent on artificial nutrition, are eligible for inclusion. This study will randomize critically ill children (n=140) to a continuous versus intermittent nutrition strategy. In both groups, similar daily caloric targets will be prescribed. In the continuous group (control), nutrition will be administered 24 hours a day, with a maximum interruption period of 2 hours. In the intermittent group (intervention), nutrition will be interrupted during an age-dependent overnight fasting period. The study intervention will last until admission day 14, initiation of oral intake, or discharge from the PICU, whichever comes first. The primary outcome is the difference in ketosis between the groups under the condition of noninferiority regarding caloric intake. Secondary outcomes are feeding intolerance; the proportion of severe and resistant hypoglycemic events and severe gastrointestinal complications; and additional observed effects on nutritional intake, circadian rhythm, and clinically relevant outcome measures of the intermittent feeding strategy compared with continuous nutrition. RESULTS: The study was approved by the Dutch national ethical review board in February 2020. The first patient was enrolled on May 19, 2020. By May 2022, a total of 132 patients had been included in the study. Recruitment of the last patient is expected in Q3 2022. CONCLUSIONS: Although intermittent fasting has been proven to have many health benefits in both animal and human studies, the feasibility and safety of this strategy in a PICU setting must be investigated. This RCT will help physicians gain more insight into the feasibility, safety, and potential clinical effects of intermittent feeding with overnight fasting in critically ill children. TRIAL REGISTRATION: Netherlands Trial Register NL7877; https://trialsearch.who.int/Trial2.aspx?TrialID=NL7877. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/36229.

Intermittent fasting in paediatric critical illness: The properties and potential beneficial effects of an overnight fast in the PICU.

Although evidence for the superiority of continuous feeding over intermittent feeding is lacking, in most paediatric intensive care units (PICU) artificial feeding is administered continuously for 24 h per day. Until now, studies in PICU on intermittent feeding have primarily focused on surrogate endpoints such as nutritional intake and gastro-intestinal complaints and none have studied the effects of an extended fasting period. Intermittent fasting has been proven to have many health benefits in both animal and human studies. The observed beneficial effects are based on multiple metabolic and endocrine changes that are presumed crucial in critical illness as well. One key element is the transition to ketone body metabolism, which, among others, contributes to the stimulation of several cellular pathways involved in stress resistance (neuro)plasticity and mitochondrial biogenesis, and might help preserve brain function. Secondly, the fasting state stimulates the activation of autophagy, a process that is crucial for cellular function and integrity. Of the different intermittent fasting strategies investigated, time-restricted feeding with a daily extended fasting period appears most feasible in the PICU. Moreover, planning the fasting period overnight could help maintain the circadian rhythm. Although not investigated, such an overnight intermittent fasting strategy might improve the metabolic profile, feeding tolerance and perhaps even have beneficial effects on tissue repair, reperfusion injury, muscle weakness, and the immune response. Future studies should investigate practical implications in critically ill children and the optimal duration of the fasting periods, which might be affected by the severity of illness and by age.