R S Horne

..We investigated whether the prone sleeping position impaired arousal from sleep in healthy preterm infants and whether this impairment was related to cardiorespiratory variables, temperature or postnatal age...

..We addressed this issue by measuring BP noninvasively and continuously during sleep in children with a range of severities of SDB and in a group of nonsnoring control children...

..It has been suggested that this increased risk is due to immature autonomic control. This article provides an overview of studies assessing autonomic control of the cardiovascular system in preterm infants...

..This review summarises normal development of cardiovascular control during sleep in infants and describes the association of impaired cardiovascular control with the three overlapping factors proposed to be involved in SIDS pathogenesis...

..Infants at increased risk for SIDS have been shown to have both depressed ventilatory and arousal responses to hypoxia, thus they may be at even greater risk...

..Any impairment in arousability from sleep could occur when infants are exposed to maternal cigarette smoking, and could possibly contribute to the final pathway to SIDS...

..Arousability is depressed by the major risk factors for SIDS (prone sleeping, maternal smoking, prematurity and recent infection) and is increased by factors that decrease the risk for SIDS (e.g. use of dummies, breastfeeding)...

..Previously it has been shown that arousability is impaired by the major risk factors for SIDS such as prone sleeping and maternal smoking...

..We conclude that a history of prematurity with neonatal apnoea has a persisting effect on decreasing arousabilty from sleep and these infants may be at increased risk for SIDS...

..In this study spindle density and the percentage time spent with spindles were not well correlated with infant arousability, and hence may not be able to be used as markers of depressed arousal responses in infants...

..This study provides evidence that arousability from QS is impaired following an infection and we postulate that this may explain the increased risk for SIDS following infection observed in previous studies...

..Any impairment in arousability from sleep such as could occur when infants sleep in the prone position, could possibly contribute to the final pathway to SIDS...

..Multiple measurements of arousal threshold (cm H(2)O) in response to air-jet stimulation applied alternately to the nares were made in both active sleep and quiet sleep when infants slept both prone and supine...

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..Impairment of heart rate control in the prone position may be important in understanding the increased risk for SIDS in this position...

..This mechanism may account for the increased risk for SIDS of preterm infants...

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..We conclude that the greater desaturation during a hypoxic challenge combined with the longer arousal latency in preterm infants could contribute to greater risk for SIDS...

..We conclude that the ventilatory responses preceding hypoxia-induced arousal do not differ between sleep-states and that arousal occurs at similar levels of desaturation in both states...

..This study supports the nasal air-jet as an appropriate stimulus for assessing developmental patterns of infant arousal process...

..To determine the effects of sleeping position on development of circulatory control in infants over the first 6 months of postnatal age (PNA)...

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..The consequences of disrupted thermogenesis during REM sleep include dependence of Tb upon the prevailing ambient temperature, and abbreviation of the REM epoch by arousal, possibly as a defence against falls in Tb in cool Ta...

..Infants are less arousable to both stimulus modalities in QS than in AS, and less arousable at 5 to 6 months of age than at 2 to 4 weeks in QS...

..We suggest that arousal in response to hypoxia, particularly in AS, is a vital survival mechanism throughout the first 6 months of life...

..This finding highlights the importance of considering sleep state distribution of events in studies of the pathophysiology and outcomes of OSA in childhood...

..We hypothesized that CA frequency would be lower and CA threshold would be higher in male infants during both active (AS) and quiet (QS) sleep...

..This study aimed to quantify the effect of PLMS episodes during NREM2 sleep on heart rate variability (HRV) measures of sympathovagal balance in children...

..These data suggest that movement-induced CAs should be considered when assessing the cardiovascular impact of SDB...

..We aimed to test the hypothesis that BP and HR are augmented during obstructive events in children equivalent to levels reported in adults...

..To investigate the effects of swaddling experience on infant sleep, spontaneous arousal patterns and autonomic control...

..05). Accounting for the HPD of infancy provides estimates of BRS in the time domain that closely parallel spectral estimates, and provides a novel analytical tool to assess normal development and dysfunction of the baroreflex in infants...

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..We contrasted the relationship between cerebral perfusion and oxygen metabolism in preterm infants treated with dopamine because of hypotension with normotensive controls...

..We aimed to examine the arousal process in a group of infants exposed to maternal smoking, who are thus at higher risk for SIDS...

..CONCLUSION: In sleeping infants, mild hypoxia serves as a stimulus for arousal in both AS and QS. Of particular significance is our finding that arousal from AS is readily elicited by mild hypoxia...

..There was no difference across ages in AR or sensitivity. PVW and specificity values were low in this study. We conclude that actigraphy is a valid method for monitoring sleep in infants who are younger than 6 mo...

..By performing only one test or by failing to account for arousal responses, previous studies may not have detected the natural variation of the infant HVR...

..This study confirms that PCD declines after birth. The disagreement between our data and theoretical predictions of PCD may point to important differences between the respiratory controller of the infant and adult...

..This attenuated cardiovascular response could be due to reduced sympathetic activation or blunted vagal withdrawal and may have implications for the child with DS and OSA...

..To evaluate the effects of swaddling on infant arousability, particularly the progression of subcortical activation (SCA) to full cortical arousal (CA), because impaired arousal may contribute to sudden infant death syndrome...

..We aimed to compare NP and Th measurement techniques when scoring central and obstructive respiratory events during PSG...

..The ability to continuously measure BP and baroreflex sensitivity during sleep in infants may provide vital clues into pathologic conditions associated with impaired autonomic control during sleep...

..We conclude that actigraphy is a reliable method for determining sleep in children when compared against PSG. Actigraphy may be a useful tool in paediatric sleep clinics and research...

..In conclusion actigraphy provides a useful tool for assessing the development infant sleep...

..However, there have been limited studies in infants and to date there have been no studies to validate the reliability of actigraphy in preterm infants...

..quot;Adaptability" was the only significant predictor of arousability in QS. This study demonstrates that temperament characteristics as measured by questionnaire may not be reliable indicators of arousability from sleep...

..We assessed the effects of sleeping position, sleep state, and postnatal age on cerebral oxygenation by measuring tissue oxygenation index (TOI) during the first 6 months of infancy...

..Continued research is needed to identify the pathophysiological basis of SIDS...

..We hypothesised that infants with more regular sleep/wake patterns and longer sleep durations would have an easier temperament and higher developmental scores...