Spontaneous Arousals in Supine Infants While Swaddled and Unswaddled During Rapid Eye Movement and Quiet Sleep

Abstract

ABSTRACT. Objective. Supine sleep is recommended for infants to decrease the risk of sudden infant death syndrome, but many parents report that their infants seem uncomfortable supine. Many cultures swaddle infants for sleep in the supine position. Swaddled infants are said to "sleep better"; presumably they sleep longer or with fewer arousals. However, there have been no studies of the effect of swaddling on spontaneous arousals during sleep. Arousal is initiated in brainstem centers and manifests as a sequence of reflexes: from sighs to startles and then to thrashing movements. Such "brainstem arousals" may progress to full arousal, but most do not.Methods. Twenty-six healthy infants, aged 80 ؎ 7 days, were studied during normal nap times. Swaddled (cotton spandex swaddle) and unswaddled trials were alternated for each infant. Sleep state (rapid eye move- ment [REM] or quiet sleep [QS]) was determined by behavioral criteria (breathing pattern, eye movements) and electroencephalogram/electrooculogram (10 infants).Respitrace, submental and biceps electromyogram, and video recording were used to detect startles and sighs (augmented breaths). Full arousals were classified by eye opening and/or crying. Frequencies of sighs, startles, and full arousals per hour were calculated. Progression of events was calculated as percentages in each sleep state, as was duration of sleep state.Results. Swaddling decreased startles in QS and REM, full arousal in QS, and progression of startle to arousal in QS. It resulted in shorter arousal duration during REM sleep and more REM sleep.Conclusions. Swaddling has a significant inhibitory effect on progression of arousals from brainstem to full arousals involving the cortex in QS. Swaddling decreases spontaneous arousals in QS and increases the duration of REM sleep, perhaps by helping infants return to sleep spontaneously, which may limit parental intervention. For these reasons, a safe form of swaddling that allows hip flexion/abduction and chest wall excursion may help parents keep their infants in the supine sleep position and thereby prevent the sudden infant death syndrome risks associated with the prone sleep position. Pediatrics 2002;110(6). URL: http://www.pediatrics.org/cgi/content/ full/110/6/e70; sudden infant death syndrome, sighs, startles.ABBREVIATIONS. SIDS, sudden infant death syndrome; REM, rapid eye movement; QS, quiet sleep; EMG, electromyogram; EEG, electroencephalogram; EOG, electrooculogram. S upine sleeping decreases the risk for sudden infant death syndrome (SIDS). 1 However, some parents place their infants in the prone sleep position despite these recommendations. [2][3][4] Many of these parents state that their infants seem more comfortable when prone and sleep better. 4 Studies confirm that the prone position decreases frequency of arousals. [5][6][7][8][9] Swaddled infants placed on their backs are said to "sleep better," presumably meaning that they sleep longer or with fewer arousals. Parents commonly report that infants who are back sleepers "startle ...

Theory of Mind: Towards an Evolutionary Theory

“…32 Even more interesting is the finding that swaddling enhances the incidence of REM sleep in infants and has an inhibitory effect on spontaneous arousals during sleep (Gerard et al 2002;Franco et al 2005). 33 These findings are well in line with postulates of the present hypothesis.…”

Swaddling and the Risk of Sudden Infant Death Syndrome: A Meta-analysis

“…It has been reported that swaddling infants for sleep is gaining popularity in countries such as the United Kingdom and the United States, [1][2][3] with several reported benefits to the practice. For the general population of young infants, these include more quiet sleep, 3 fewer spontaneous arousals during quiet sleep, 4 and a slight reduction in excessive crying in infants aged <7 weeks. 5 Further benefits are observed for specific populations, including improvements in neuromuscular development for very low birth weight infants, 6 reduced physiologic and behavioral distress among premature infants, 7 and improved calming and sleep for infants with neonatal abstinence syndrome.…”

“…11 In contrast, there is evidence that swaddling may increase the risk of SIDS, as swaddled infants have fewer spontaneous arousals from sleep and increased sleep time, particularly during quiet sleep, which is a state of reduced arousability. 4 In addition, those infants who were naive to swaddling (ie, not routinely swaddled) had higher induced arousal thresholds in both sleep states 2 and reduced spontaneous arousability in active sleep. 12 Beyond the field of SIDS, swaddling may also increase an infant's risk for developmental dysplasia of the hip (especially if not applied well), 13 hyperthermia, 1 pneumonia, and upper respiratory tract infections.…”

The Influence of Positioning on Spontaneous Movements of Preterm Infants

“…Third, it facilitates the development of sensorimotor experiences and promotes neuronal maturation since infants interact with their environment through their own activities. Positioning has been employed in developmental care [23][24][25] using the swaddling and nesting technique, and there are some studies reporting the effects of these techniques [26][27][28][29][30] . However, most of the research has focused on developmental care as a whole and little is known about the effect of the positioning technique on the movement patterns of very lowbirth-weight infants.…”