Research Priorities in Sudden Unexpected Infant Death: An International Consensus.

Despite the success of safe sleep campaigns and the progress in understanding risk factors, the rate of reduction in the cases of sudden infant death syndrome has now slowed and it remains a leading cause of postneonatal mortality in many developed countries. Strategic action is needed to tackle this problem and it is now vital to identify how the sudden infant death research community may best target its efforts. The Global Action and Prioritization of Sudden Infant Death Project was an international consensus process that aimed to define and direct future research by investigating the priorities of expert and lay members of the sudden unexpected infant death (SUID) community across countries. The aim was to identify which areas of research should be prioritized to reduce the number of SUID deaths globally. Scientific researchers, clinicians, counselors, educators, and SUID parents from 25 countries took part across 2 online surveys to identify potential research priorities. Workshops subsequently took place in the United Kingdom, United States, and Australia to reach consensus and 10 priority areas for research were established. Three main themes among the priorities emerged: (1) a better understanding of mechanisms underlying SUID, (2) ensuring best practice in data collection, management and sharing, and (3) a better understanding of target populations and more effective communication of risk. SUID is a global problem and this project provides the international SUID community with a list of shared research priorities to more effectively work toward explaining and reducing the number of sudden infant deaths.

Early postnatal exposure to intermittent hypoxia in rodents is proinflammatory, impairs white matter integrity, and alters brain metabolism.

BackgroundPreterm infants are frequently exposed to intermittent hypoxia (IH) associated with apnea and periodic breathing that may result in inflammation and brain injury that later manifests as cognitive and executive function deficits. We used a rodent model to determine whether early postnatal exposure to IH would result in inflammation and brain injury.MethodsRat pups were exposed to IH from P2 to P12. Control animals were exposed to room air. Cytokines were analyzed in plasma and brain tissue at P13 and P18. At P20-P22, diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS) were performed.ResultsPups exposed to IH had increased plasma Gro/CXCL1 and cerebellar IFN-γ and IL-1ß at P13, and brainstem enolase at P18. DTI showed a decrease in FA and AD in the corpus callosum (CC) and cingulate gyrus, and an increase in RD in the CC. MRS revealed decreases in NAA/Cho, Cr, Tau/Cr, and Gly/Cr; increases in TCho and GPC in the brainstem; and decreases in NAA/Cho in the hippocampus.ConclusionsWe conclude that early postnatal exposure to IH, similar in magnitude to that experienced in human preterm infants, is associated with evidence for proinflammatory changes, decreases in white matter integrity, and metabolic changes consistent with hypoxia.

Salivary caffeine concentrations are comparable to plasma concentrations in preterm infants receiving extended caffeine therapy.

AIMS: Caffeine concentrations in preterm infants are usually measured in the blood. However, salivary assays may provide a valid and practical alternative. The present study explored the validity and clinical utility of salivary caffeine concentrations as an alternative to blood concentrations and developed a novel plasma/salivary caffeine distribution model. METHODS: Paired salivary and plasma samples were obtained in 29 infants. Salivary samples were obtained using a commercially available salivary collection system. Caffeine concentrations in the saliva and plasma were determined using high-performance liquid chromatography. A population pharmacokinetic (PK) model was developed using NONMEM 7.3. RESULTS: The mean (± standard deviation) gestational age (GA) at birth and birth weight were 27.9 ± 2.1 weeks and 1171.6 ± 384.9 g, respectively. Paired samples were obtained at a mean postmenstrual age (PMA) of 35.5 ± 1.1 weeks. The range of plasma caffeine concentrations was 9.5-54.1 µg ml(-1) , with a mean difference (95% confidence interval) between plasma and salivary concentrations of -0.18 µg ml(-1) (-1.90, 1.54). Salivary and plasma caffeine concentrations were strongly correlated (Pearson's correlation coefficient = 0.87, P < 0.001). Caffeine PK in plasma and saliva was simultaneously described by a three-compartment recirculation model. Current body weight, birth weight, GA, PMA and postnatal age were not significantly correlated with any PK parameter. CONCLUSIONS: Salivary sampling provides an easy, non-invasive method for measuring caffeine concentrations. Salivary concentrations correlate highly with plasma concentrations. Caffeine PK in saliva and plasma are well described by a three-compartment recirculation model.

Assigning cause for sudden unexpected infant death.

We have reached a conundrum in assigning cause of death for sudden unexpected infant deaths. We summarize the discordant perspectives and approaches and how they have occurred, and recommend a pathway toward improved consistency. This lack of consistency affects pediatricians and other health care professionals, scientific investigators, medical examiners and coroners, law enforcement agencies, families, and support or advocacy groups. We recommend that an interdisciplinary international committee be organized to review current approaches for assigning cause of death, and to identify a consensus strategy for improving consistency. This effort will need to encompass intrinsic risk factors or infant vulnerability in addition to known environmental risk factors including unsafe sleep settings, and must be sufficiently flexible to accommodate a progressively expanding knowledge base.

Effects of caffeine on intermittent hypoxia in infants born prematurely: a randomized clinical trial.

IMPORTANCE: Preterm infants have immature respiratory control and resulting intermittent hypoxia (IH). The extent of IH after stopping routine caffeine treatment and the potential for reducing IH with extended caffeine treatment are unknown. OBJECTIVES: To determine (1) the frequency of IH in premature infants after discontinuation of routine caffeine treatment and (2) whether extending caffeine treatment to 40 weeks' postmenstrual age (PMA) reduces IH. DESIGN, SETTING, AND PARTICIPANTS: A prospective randomized clinical study was conducted at 16 neonatal intensive care units in the United States, with an 18-month enrollment period. Preterm infants (<32 weeks' gestation) previously treated with caffeine were randomized to extended caffeine treatment or usual care (controls) at a PMA of at least 34 weeks but less than 37 weeks. Continuous pulse oximeter recordings were obtained through 40 weeks' PMA. Oximeter data were analyzed by persons masked to patient group. INTERVENTION: Continued treatment with caffeine. MAIN OUTCOMES AND MEASURES: Number of IH events and seconds with less than 90% hemoglobin oxygen saturation (Sao2) per hour of recording. RESULTS: Our analysis included 95 preterm infants. In control infants, the mean (SD) time at less than 90% Sao2 at 35 and 36 weeks' PMA was 106.3 (89.0) and 100.1 (114.6) s/h, respectively. The number of IH events decreased significantly from 35 to 39 weeks' PMA (P = .01). Extended caffeine treatment reduced the mean time at less than 90% Sao2 by 47% (95% CI, -65% to -20%) to 50.9 (48.1) s/h at 35 weeks and by 45% (95% CI, -74% to -17%) to 49.5 (52.1) s/h at 36 weeks. CONCLUSIONS AND RELEVANCE: Substantial IH persists after discontinuation of routine caffeine treatment and progressively decreases with increasing PMA. Extended caffeine treatment decreases IH in premature infants. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01875159.