Softness and potential to cause rebreathing: Differences in bedding used by infants at high and low risk for sudden infant death syndrome

Evidence Base for 2022 Updated Recommendations for a Safe Infant Sleeping Environment to Reduce the Risk of Sleep-Related Infant Deaths

Every year in the United States, approximately 3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Statistical Classification of Diseases and Related Health Problems 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths have remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. In addition, additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, which is included in this issue.

Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment

Each year in the United States, ∼3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Classification of Diseases, 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths has remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. Additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is also included. The recommendations and strength of evidence for each recommendation are included in this policy statement. The rationale for these recommendations is discussed in detail in the accompanying technical report.

Infant inclined sleep product safety: A model for using biomechanics to explore safe infant product design

Over 450 adverse incidents have been reported in infant inclined sleep products over the past 17 years, with many infants found dead in both the supine and prone positions. The unique design of inclined sleep products may present unexplored suffocation risks related to how these products impact an infant's ability to move. The purpose of this study was to assess body movement and muscle activity of healthy infants when they lie supine and prone on different inclined sleep products. Fifteen healthy full-term infants (age: 17.7 ± 4.9 weeks) were recruited for this IRB-approved study. Three inclined sleep products with unique features, representative of different sleeper designs, were included. Surface electromyography (EMG) was recorded from infants' cervical paraspinal, abdominal, and lumbar erector spinae muscles for 60 s during supine and prone positioning. Neck and trunk sagittal plane movements were evaluated for each testing condition. Paired t-tests and Wilcoxon signed-rank tests were performed to compare each inclined sleeper to a flat crib mattress (0° baseline condition). During prone positioning, abdominal muscle activity significantly nearly doubled for all inclined sleep products compared to the flat crib mattress, while erector spinae muscle activity decreased by up to 48%. Trunk movement significantly increased compared to the flat crib mattress during prone lying. During prone lying, inclined sleep products resulted in significantly higher muscle activity of the trunk core muscles (abdominals) and trunk movement, which has the potential to exacerbate fatigue and contribute to suffocation if an infant cannot self-correct to the supine position.

A firm recommendation: measuring the softness of infant sleep surfaces

Background

Approximately 3600 sudden unexpected infant deaths (SUID) occur annually in the United States, and a quarter of SUIDs are caused by unintentional suffocation and strangulation in bed, with soft bedding use being a significant risk factor. Therefore, The American Academy of Pediatrics (AAP) recommends infants sleep on a “firm” surface, though neither an objective definition nor national standard has been established. The purpose of this study is to report on the performance of a device that measures mattress softness and to provide quantitative values of softness for various infant sleep surfaces.

Methods

In collaboration with the authors and a national child product safety organization (Kids in Danger), University of Michigan engineering students designed and validated a device that measures the vertical depression (softness) of a simulated 2-month-old’s head on a sleep surface. A total of 17 infant sleep surfaces − 14 household surfaces and 3 hospital mattresses - were measured between April 2019 and January 2020. The average softness of each surface was calculated. Surfaces were also measured with soft bedding, which included an infant fleece blanket, and firm and soft pillows.

Results

The average softness for the 14 household sleep surfaces ranged from 7.4–36.9 mm. The 2019 cribette playard and the 2018 infant spring had similar softness (21 mm) as the 2018 and 2019 adult foam and 2015 sofa. An infant’s fleece blanket folded once added an additional 2.3–6.5 mm of softness, folded twice added 4.8–11.6 mm, and folded three times added 11–21.8 mm. Using a firm pillow added 4.0–20.9 mm of softness while using a soft pillow added 24.5–46.4 mm. The softness for the 3 hospital sleep surfaces ranged from 14 to 36.9 mm, with the infant bassinet being the firmest and the pediatrics mattress being the softest.

Conclusions

We found a wide range of softness among sleep surfaces, with some infant mattresses as soft as some adult mattresses. Adding blankets and pillows to mattresses measurably increased softness. Quantifying sleep surface softness will advance our understanding of how softness relates to SUID risk. We hope this new information will further inform safe infant sleep recommendations and improve mattress safety standards nationally.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40621-021-00325-x.

Transition to a Safe Home Sleep Environment for the NICU Patient

Of the nearly 3.8 million infants born in the United States in 2018, 8.3% had low birth weight (<2500 g [5.5 lb]) and 10% were born preterm (gestational age of <37 completed weeks). Many of these infants and others with congenital anomalies, perinatally acquired infections, and other disease require admission to a NICU. In the past decade, admission rates to NICUs have been increasing; it is estimated that between 10% and 15% of infants will spend time in a NICU, representing approximately 500 000 neonates annually. Approximately 3600 infants die annually in the United States from sleep-related deaths, including sudden infant death syndrome International Classification of Diseases, 10th Revision (R95), ill-defined deaths (R99), and accidental suffocation and strangulation in bed (W75). Preterm and low birth weight infants are particularly vulnerable, with an incidence of death 2 to 3 times greater than healthy term infants. Thus, it is important for health care professionals to prepare families to maintain their infant in a safe sleep environment, as per the recommendations of the American Academy of Pediatrics. However, infants in the NICU setting commonly require care that is inconsistent with infant sleep safety recommendations. The conflicting needs of the NICU infant with the necessity to provide a safe sleep environment before hospital discharge can create confusion for providers and distress for families. This technical report is intended to assist in the establishment of appropriate NICU protocols to achieve a consistent approach to transitioning NICU infants to a safe sleep environment as soon as medically possible, well before hospital discharge.

Expansion of a multi-pronged safe sleep quality improvement initiative to three children's hospital campuses

Background

The American Academy of Pediatrics (AAP) recommends infants should be Alone, on their Back, and in a clear Crib to combat relatively stagnant rates of sudden unexpected infant death (SUID). These are referred to as the ABCs of safe sleep. Studies have shown these recommendations are not consistently followed in the hospital setting, but further investigation would determine how to improve the rate of adherence. The objective of this study was to evaluate the impact of an expanded safe sleep initiative at three Georgia free-standing children’s hospital campuses before and after a multipronged safe sleep initiative.

Methods

A quality improvement program with a pre/post analysis was performed using a convenience method of sampling. Infants < 12 months old in three inpatient pediatric campuses were analyzed pre- and post- interventions. The intervention included: 1) nursing education, 2) identification of nurse “safe sleep” champions, 3) crib cards, 4) crib audits, and 5) weekly reporting of data showing nursing unit ABC compliance via tracking boards. The goal was ABC compliance of ≥25% for the post-intervention period. A standardized crib audit tool evaluated sleep position/location, sleep environment, and ABC compliance (both safe position/location and environment). Chi square analysis, Fisher’s exact test, and logistic regression were used to compare safe sleep behaviors before and after the interventions.

Results

There were 204 cribs included pre-intervention and 274 cribs post-intervention. Overall, there was not a significant change in sleep position/location (78.4 to 76.6%, p = 0.64). There was a significant increase in the percent of infants sleeping in a safe sleep environment following the intervention (5.9 to 39.8%, p < 0.01). Overall ABC compliance, including both sleep position/location and environment, improved from 4.4% pre-intervention to 32.5% post-intervention (p < 0.01). There was no significant variability between the hospitals (p = 0.71, p = 1.00).

Conclusions

The AAP’s safe sleep recommendations are currently not upheld in children’s hospitals, but safer sleep was achieved across three children’s campuses in this study. Significant improvements were made in sleep environment and overall safe sleep compliance with this multi-pronged initiative.

As easy as ABC: evaluation of safe sleep initiative on safe sleep compliance in a freestanding pediatric hospital

Background

The American Academy of Pediatrics (AAP) recommends the ABCs of safe infant sleep (alone, back, clear crib) to combat the increasing rates of Sudden Unexplained Infant Death (SUID). It is unclear if these recommendations are followed for infants hospitalized in pediatric facilities after the newborn period. The objectives of this study were to assess baseline infant sleep behaviors at a tertiary care freestanding pediatric hospital and to evaluate the effectiveness of a hospital-based infant safe sleep program in improving adherence to safe sleep recommendations.

Methods

A quality improvement program with pre- and post- analyses was performed on a convenience sample of infants < 12-months old utilizing a crib audit tool on two general pediatric inpatient units. The crib audit tool was used before and after the safe sleep program intervention. It recorded the infant's sleep position, location during sleep, and sleep environment. Interventions included: 1) nursing education, 2) crib cards with a checklist of the ABC's of safe sleep provided for the cribs of hospitalized infants, and 3) tracking boards to report weekly measured compliance with the ABCs. Chi square analysis was used to compare adherence to recommendations before and after program implementation.

Results

There were 62 cribs included pre-intervention and 90 cribs post-intervention. Overall, there was no significant change in safe sleep positioning (81% to 82%, p = 0.97). There was a significant increase in adherence to the safe sleep environment recommendation (3% to 38%, p < 0.01). Overall safe sleep, including both position and environment, referred to as ABC compliance, improved from 3% pre-intervention to 34% post-intervention (p < 0.01). Only 18% of cribs audited displayed a crib card, demonstrating poor compliance on placement of the cards. There was no significant difference in compliance with safe sleep recommendations between infants with a crib card compared to those without (25% vs. 37%, p = 0.51).

Conclusions

Significant improvements were made in sleep environments and overall safe sleep compliance after introduction of crib cards and tracking boards. Most likely the crib auditing process itself and the tracking boards had a larger impact than the crib cards.

Reports of Injury Risks and Reasons for Choice of Sleep Environments for Infants and Toddlers

Objective

Compare mothers’ reports of injuries for infants and toddlers sleeping with crib-bumpers/mesh-liners/no-barriers and reasons for these sleep environment choices.

Methods

A cross-sectional survey of mothers subscribing to a parenting magazine and using crib bumpers (n = 224), mesh liners (n = 262), and no barriers (n = 842). Analyses of four possible injuries (face-covered, climb-out/fall, slat-entrapment, hit-head) including multivariate logistic regression adjusted for missing data/demographics and Chi squared analyses of reasons for mothers’ choices.

Results

Maternal reports of finding infants/toddlers with face covered had 3.5 times higher adjusted odds (aOR) for crib bumper versus mesh liner use. Breathing difficulties and wedgings were reported for infants/toddlers using crib bumpers but not mesh liners. Climb-outs/falls showed no significant difference in aORs for crib bumpers versus no-barriers and mesh liners versus no barriers. Reports of slat-entrapment were less likely for mothers using crib bumpers and mesh liners than using no barrier (aOR = .28 and .32). Reports of hit-heads were less likely for crib bumpers vs no barrier (aOR = .38) with no significant difference between mesh liners versus no barrier use. Mothers using crib bumpers and mesh liners felt their choice prevented slat-entrapment (89%, 91%); 93.5% of crib bumper users felt their choice prevented hit-heads. Significantly more mesh liner than crib bumper users chose them because “There is no suffocation risk” (64.1% vs. 40.6%), while 83.6% of no-barrier users chose them because “I was concerned about suffocation risk.”

Conclusions for Practice

Mothers appeared to be more concerned about preventing minor risks than suffocation. Understanding reasons for mothers’ use of barriers/no-barriers is important in tailoring counseling for mothers with infants/toddlers.

Electronic supplementary material

The online version of this article (10.1007/s10995-019-02803-7) contains supplementary material, which is available to authorized users.

Carbon dioxide rebreathing induced by crib bumpers and mesh liners using an infant manikin

OBJECTIVES

Quantify impaired respiration in currently marketed crib bumpers (CBs), mesh liners (MLs) and alternative products (ALTs) used to attenuate the interaction between the baby and the crib sides and elucidate the relationship between impaired respiration and permeability.

METHODS

We experimentally quantified carbon dioxide rebreathing (CO₂RB) via an infant manikin and air permeability via previously published test protocols, in commercially available CBs, MLs and ALTs.

RESULTS

Differences in CO₂RB in ML (median [m]=8.2%, 25th percentile [P25]=6.8, 75th percentile [P75]=8.6), ALT (m=10.5%, P25=9.8, P75=10.7) and CB (m=11.6%, P25=10.2, P75=14.3) were significant (p<0.0001). For comparison, manikin tests with a pacifier yielded CO₂RB of 5.6%-5.9%, blanket draped over the face/torso yielded CO₂RB of 7.7%-8.6% and stuffed animal in various positions yielded CO₂RB from 6.1% to 16.1%. Differences in permeability between ML (m=529.5 cubic feet per minute [CFM], P25=460, P75=747.5), ALT (m=29.0 CFM, P25=27.7, P75=37.7) and CB (m=46.6 CFM, P25=30.1, P75=58.7) groups were significant (p<0.0001). CO₂RB was poorly correlated with air permeability (max R²=0.36). In a subset of tests, CB CO₂RB increased by 50%-80% with increasing penetration force, whereas the ML CO₂RB was nominally unchanged.

CONCLUSIONS

Government agencies and standards organisations are presently considering regulation of bedding including CBs. As paediatricians are consulted in the development of such regulations, our findings that permeability by itself was a poor predictor of CO₂RB should be considered.

Adherence to Safe Sleep Recommendations by Families With Higher-order Multiples

BACKGROUND

More than 95% of higher-order multiples are born preterm and more than 90% are low birth weight, making this group of infants especially vulnerable to sudden infant death syndrome (SIDS). Emerging evidence suggests that families with twins face challenges adhering to the American Academy of Pediatrics (AAP) recommendations to reduce SIDS risks. Adherence to the AAP recommendations in families with higher-order multiples has not been described.

PURPOSE

This study describes SIDS risk reduction infant care practices for higher-order multiples during the first year of life.

METHODS

Mothers caring for higher-order multiple-birth infants were recruited from an online support group. An online survey was used to assess infant care practices when the infants were first brought home from the hospital as well as at the time of the survey.

RESULTS

Ten mothers of triplets and 4 mothers of quadruplets responded. Less than 80% of the mothers practiced "back to sleep" immediately postdischarge. Supine sleep positioning decreased over time, particularly during daytime naps. Only 50% of the infants shared the parents' bedroom and approximately 30% bed-shared with their siblings. Sleep-time pacifier use was low.

IMPLICATIONS FOR PRACTICE

Safe sleep education must include specific questions regarding home sleeping arrangements, encouragement of breast milk feedings, supine positioning, and pacifier use at every sleep for higher-order multiple infants well before discharge in order for parents to plan a safe sleep environment at home.

IMPLICATIONS FOR RESEARCH

Prospective studies to identify barriers and facilitators can inform future strategies supporting adherence to safe sleep practices for higher-order multiple infants.

SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment

Approximately 3500 infants die annually in the United States from sleep-related infant deaths, including sudden infant death syndrome (SIDS), ill-defined deaths, and accidental suffocation and strangulation in bed. After an initial decrease in the 1990s, the overall sleep-related infant death rate has not declined in more recent years. Many of the modifiable and nonmodifiable risk factors for SIDS and other sleep-related infant deaths are strikingly similar. The American Academy of Pediatrics recommends a safe sleep environment that can reduce the risk of all sleep-related infant deaths. Recommendations for a safe sleep environment include supine positioning, use of a firm sleep surface, room-sharing without bed-sharing, and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include avoidance of exposure to smoke, alcohol, and illicit drugs; breastfeeding; routine immunization; and use of a pacifier. New evidence and rationale for recommendations are presented for skin-to-skin care for newborn infants, bedside and in-bed sleepers, sleeping on couches/armchairs and in sitting devices, and use of soft bedding after 4 months of age. In addition, expanded recommendations for infant sleep location are included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, "SIDS and Other Sleep-Related Infant Deaths: Updated 2016 Recommendations for a Safe Infant Sleeping Environment," which is included in this issue.

Controversies in pediatric forensic pathology

Pediatric forensic pathology is an emerging medical subspecialty that spans the area between pediatric and forensic pathology. Advances in both of these fields have increased the sophistication of diagnoses, with overlap of disorders that might present to either the pediatric or forensic pathologist, adding further layers of complexity. Not surprisingly, therefore, there are important ethical and medical controversies in pediatric forensic pathology that merit careful consideration and attention.

Sofas and infant mortality

OBJECTIVE

Sleeping on sofas increases the risk of sudden infant death syndrome and other sleep-related deaths. We sought to describe factors associated with infant deaths on sofas.

METHODS

We analyzed data for infant deaths on sofas from 24 states in 2004 to 2012 in the National Center for the Review and Prevention of Child Deaths Case Reporting System database. Demographic and environmental data for deaths on sofas were compared with data for sleep-related infant deaths in other locations, using bivariate and multivariable, multinomial logistic regression analyses.

RESULTS

A total of 1024 deaths on sofas made up 12.9% of sleep-related infant deaths. They were more likely than deaths in other locations to be classified as accidental suffocation or strangulation (adjusted odds ratio [aOR] 1.9; 95% confidence interval [CI], 1.6-2.3) or ill-defined cause of death (aOR 1.2; 95% CI, 1.0-1.5). Infants who died on sofas were less likely to be Hispanic (aOR 0.7; 95% CI, 0.6-0.9) compared with non-Hispanic white infants or to have objects in the environment (aOR 0.6; 95% CI, 0.5-0.7) and more likely to be sharing the surface with another person (aOR 2.4; 95% CI, 1.9-3.0), to be found on the side (aOR 1.9; 95% CI, 1.4-2.4), to be found in a new sleep location (aOR 6.5; 95% CI, 5.2-8.2), and to have had prenatal smoke exposure (aOR 1.4; 95% CI, 1.2-1.6). Data on recent parental alcohol and drug consumption were not available.

CONCLUSIONS

The sofa is an extremely hazardous sleep surface for infants. Deaths on sofas are associated with surface sharing, being found on the side, changing sleep location, and experiencing prenatal tobacco exposure, which are all risk factors for sudden infant death syndrome and sleep-related deaths.

Infant asphyxia, soft mattresses, and the "trough" effect

Although unexpected infant death in a cot has traditionally been attributed to sudden infant death syndrome, careful evaluation of death scenes and sleeping environments has increasingly identified deaths due to accidental asphyxia from so-called sleeping accidents. The case of a 5-month-old infant boy who was found facedown and unresponsive in a wooden portable cot with a sagging canvas base is reported to illustrate another potentially lethal situation. Although the autopsy revealed no specific findings, examination of the cot showed a significant depression caused by the sagging canvas base that was exacerbated by a soft-foam mattress and layers of bedding. Once in the trough, the infant would not have been able to extricate himself. Death was therefore attributed to accidental suffocation due to the infant's position resulting in contact of the mouth and face with soft bedding. In addition to again demonstrating the potential dangers of using old second-hand cots, this case clearly shows the problems that may exist when soft and sagging bedding forms a central trough that may entrap an infant. Death scene investigators should specifically comment on the presence of such troughs and measure of depth of the trough and/or cot base to provide some quantification of the degree of concavity present.

SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment

Despite a major decrease in the incidence of sudden infant death syndrome (SIDS) since the American Academy of Pediatrics (AAP) released its recommendation in 1992 that infants be placed for sleep in a nonprone position, this decline has plateaued in recent years. Concurrently, other causes of sudden unexpected infant death occurring during sleep (sleep-related deaths), including suffocation, asphyxia, and entrapment, and ill-defined or unspecified causes of death have increased in incidence, particularly since the AAP published its last statement on SIDS in 2005. It has become increasingly important to address these other causes of sleep-related infant death. Many of the modifiable and nonmodifiable risk factors for SIDS and suffocation are strikingly similar. The AAP, therefore, is expanding its recommendations from being only SIDS-focused to focusing on a safe sleep environment that can reduce the risk of all sleep-related infant deaths including SIDS. The recommendations described in this report include supine positioning, use of a firm sleep surface, breastfeeding, room-sharing without bed-sharing, routine immunization, consideration of a pacifier, and avoidance of soft bedding, overheating, and exposure to tobacco smoke, alcohol, and illicit drugs. The rationale for these recommendations is discussed in detail in this technical report. The recommendations are published in the accompanying "Policy Statement--Sudden Infant Death Syndrome and Other Sleep-Related Infant Deaths: Expansion of Recommendations for a Safe Infant Sleeping Environment," which is included in this issue (www.pediatrics.org/cgi/doi/10.1542/peds.2011-2220).

SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment

Despite a major decrease in the incidence of sudden infant death syndrome (SIDS) since the American Academy of Pediatrics (AAP) released its recommendation in 1992 that infants be placed for sleep in a nonprone position, this decline has plateaued in recent years. Concurrently, other causes of sudden unexpected infant death that occur during sleep (sleep-related deaths), including suffocation, asphyxia, and entrapment, and ill-defined or unspecified causes of death have increased in incidence, particularly since the AAP published its last statement on SIDS in 2005. It has become increasingly important to address these other causes of sleep-related infant death. Many of the modifiable and nonmodifiable risk factors for SIDS and suffocation are strikingly similar. The AAP, therefore, is expanding its recommendations from focusing only on SIDS to focusing on a safe sleep environment that can reduce the risk of all sleep-related infant deaths, including SIDS. The recommendations described in this policy statement include supine positioning, use of a firm sleep surface, breastfeeding, room-sharing without bed-sharing, routine immunizations, consideration of using a pacifier, and avoidance of soft bedding, overheating, and exposure to tobacco smoke, alcohol, and illicit drugs. The rationale for these recommendations is discussed in detail in the accompanying "Technical Report--SIDS and Other Sleep-Related Infant Deaths: Expansion of Recommendations for a Safe Infant Sleeping Environment," which is included in this issue of Pediatrics (www.pediatrics.org/cgi/content/full/128/5/e1341).

Decisions of black parents about infant bedding and sleep surfaces: a qualitative study

OBJECTIVE

The goal of this qualitative study was to examine factors influencing decisions by black parents regarding use of soft bedding and sleep surfaces for their infants.

METHODS

We conducted focus groups and individual interviews with black mothers of lower and higher socioeconomic status (SES). Mothers were asked about many infant care practices, including sleep surface and bedding.

RESULTS

Eighty-three mothers were interviewed, 73 (47 lower and 26 higher SES) in focus groups and 10 (7 lower and 3 higher SES) in individual interviews. The primary reason for using soft surfaces was infant comfort. Parents perceived that infants were uncomfortable if the surface was not soft. Many parents also interpreted "firm sleep surface" to mean taut; they were comfortable with and believed that they were following recommendations for a firm sleep surface when they placed pillows/blankets on the mattress as long as a sheet was pulled tautly over the pillows/blankets. The primary reasons for using soft bedding (including bumper pads) were comfort, safety, and aesthetics. In addition to using bedding to soften sleep surfaces, bedding was used to prevent infant rollover and falls, particularly for infants sleeping on a bed or sofa. Some parents used soft bedding to create an attractive space for the infant.

CONCLUSIONS

Many black parents believe that soft bedding will keep their infant safe and comfortable. There is much misunderstanding about the meaning of a "firm" sleep surface. Additional educational messages apparently are needed to change parental perceptions and practices.

Airway covering during bed-sharing

BACKGROUND

Parent-infant bed-sharing is a common practice in Western post-industrial nations with up to 50% of infants sleeping with their parents at some point during early infancy. However, researchers have claimed that infants may be at risk of suffocation or sudden infant death syndrome related to airway covering or compression in the bed-sharing environment. To further understand the role of airway covering and compression in creating risks for bed-sharing infants, we report here on a sleep-lab trial of two infant sleep conditions.

METHODS

In a sleep-lab environment 20 infants aged 2-3 months old slept in their parents' bed, and in a cot by the bed, on adjacent nights. Infants' oxygen saturation and heart rate were monitored physiologically while infant and parental behaviours were recorded via ceiling-mounted infra-red cameras. Infants served as their own controls. Continuous 8-h recordings were obtained for covering of infant external airways, levels of infant oxygen saturation, infant heart rate, evidence of parental compression/overlying of infant, circumstances leading up to potential infant airway obstruction, and parental awareness of and responses to infant airway covering.

RESULTS

The majority of infants (14/20) spent some part of the bed night with their airways (both mouth and nose) covered, compared with 2/20 on the cot night; however, no consistent effect on either oxygen saturation levels or heart rate was revealed, even during prolonged bouts of airway covering. All cases of airway covering were initiated by parents; 70% were terminated by parents, the remainder by infants. Seven bouts of potential compression were observed with parental limbs resting across infant bodies for lengthy periods, however, in only two cases was the full weight of a parental limb resting on an infant, both events lasting less than 15 s, both being terminated by infant movement.

CONCLUSION

Although numerous authors have suggested that bed-sharing infants face risks because of airway covering by bed-clothes or parental bodies, the present trial does not lend support to this hypothesis.

Bassinet use and sudden unexpected death in infancy

OBJECTIVE

To analyze risk factors in infants who die suddenly and unexpectedly in bassinets.

STUDY DESIGN

A retrospective review of all deaths of infants involving bassinets reported to the Consumer Product Safety Commission (CPSC) between 1990 and 2004.

RESULTS

For the 53 deaths analyzed, the mean age at death was 84 days. The cause of death was recorded as anoxia, asphyxiation, or suffocation in 85% and sudden infant death syndrome (SIDS) in 9.4%. In terms of position, 37% were placed prone for sleep, and 50% were prone when found dead. Additional items in the bassinet, including soft bedding, were noted in 74% of cases. Specific mechanical problems with the bassinets were noted in 17% of cases.

CONCLUSIONS

The risk of sudden unexpected death in infants who sleep in bassinets can be reduced by following American Academy of Pediatrics guidelines, including positioning infants supine and avoiding soft bedding in bassinets. In addition, parents must ensure that the bassinet is mechanically sound and that no objects that can lead to suffocation are in or near the bassinet.

The effect of positioning on infant cries: implications for sudden infant death syndrome

OBJECTIVE

A definitive cause for sudden infant death syndrome (SIDS) has not yet been identified, but some theories point to laryngeal or respiratory causes, in addition to theories of reduced arousal or reduced autonomic response. The occurrence of SIDS has dropped since the movement to place newborns to sleep in the supine position; however, some research has found a respiratory disadvantage for infants in this position. The current paper studied acoustic characteristics of infant pain cries to determine the potential differences related to prone versus supine positioning.

METHODS

Fifty-one newborn infant cries were recorded during and following a blood draw screening procedure, with infants placed either in the supine or prone position. All infants were healthy, full-term infants. Complete crying episodes were audio-recorded, and results were based on compositional analysis and long-time average spectrum analysis across each crying episode.

RESULTS

Spectral analysis revealed acoustic differences related to infant positioning, and acoustic analysis also revealed that there were no respiratory differences between supine-positioned and prone-positioned infants. Overall, the acoustic differences suggest decreased arousal and/or a decreased response to pain for healthy infants recorded in the prone position.

CONCLUSIONS

As decreased arousal and prone positioning have been seen as possible causative factors for SIDS, the current results are seen as a successful step in evaluating the possibility of using acoustic analysis of infant cries as a means of evaluating SIDS risk for healthy infants.

Sudden infant death syndrome

Despite declines in prevalence during the past two decades, sudden infant death syndrome (SIDS) continues to be the leading cause of death for infants aged between 1 month and 1 year in developed countries. Behavioural risk factors identified in epidemiological studies include prone and side positions for infant sleep, smoke exposure, soft bedding and sleep surfaces, and overheating. Evidence also suggests that pacifier use at sleep time and room sharing without bed sharing are associated with decreased risk of SIDS. Although the cause of SIDS is unknown, immature cardiorespiratory autonomic control and failure of arousal responsiveness from sleep are important factors. Gene polymorphisms relating to serotonin transport and autonomic nervous system development might make affected infants more vulnerable to SIDS. Campaigns for risk reduction have helped to reduce SIDS incidence by 50-90%. However, to reduce the incidence even further, greater strides must be made in reducing prenatal smoke exposure and implementing other recommended infant care practices. Continued research is needed to identify the pathophysiological basis of SIDS.

Sleep practices and environment and the risk of sudden infant death syndrome in Turkey

PURPOSE

The aim of this study is to determine what mothers know about infant sleep practices and the environment.

DESIGN AND METHODS

Data were collected with a semistructured questionnaire. The research was conducted with 231 mothers who delivered an infant and who agreed to participate between September and December 2005.

RESULTS

It was determined that 70.6% (n = 163) of mothers would use a pillow with their sleeping infants, and 44.2% (n = 102) would cover their infants' faces. When infants were alone in a room, 96.5% of mothers would leave them in the supine position.

PRACTICE IMPLICATIONS

Public health interventions should alert women to the increased risk of sudden infant death syndrome associated with identifiable risk factors, and specific intervention campaigns for safe sleeping can be developed for Turkish families.

Sudden Infant Death Syndrome

During the last decade, much attention has been paid to the risk factors of sudden infant death syndrome (SIDS). Many researchers have demonstrated that infant-care practices are linked to the risk of SIDS. Prone sleeping, bed sharing, maternal substance abuse, and cigarette smoking have been reported to be significant potentially modifiable risk factors for SIDS. Despite the reports that the incidence of SIDS has decreased by 38% in the United States, it remains the leading cause of death in the first year of life. Deaths resulting from child abuse or neglect inflicted or permitted by their caretakers being second only to SIDS in infant mortalities and some recommendations regarding the differentiation of SIDS and child abuse have generated speculation that some cases of infanticide were misdiagnosed as SIDS. To reach a proper conclusion as to the cause and manner of death of an infant who died suddenly and unexpectedly, investigation must be thorough and professional.

The changing concept of sudden infant death syndrome: diagnostic coding shifts, controversies regarding the sleeping environment, and new variables to consider in reducing risk

There has been a major decrease in the incidence of sudden infant death syndrome (SIDS) since the American Academy of Pediatrics (AAP) released its recommendation in 1992 that infants be placed down for sleep in a nonprone position. Although the SIDS rate continues to fall, some of the recent decrease of the last several years may be a result of coding shifts to other causes of unexpected infant deaths. Since the AAP published its last statement on SIDS in 2000, several issues have become relevant, including the significant risk of side sleeping position; the AAP no longer recognizes side sleeping as a reasonable alternative to fully supine sleeping. The AAP also stresses the need to avoid redundant soft bedding and soft objects in the infant's sleeping environment, the hazards of adults sleeping with an infant in the same bed, the SIDS risk reduction associated with having infants sleep in the same room as adults and with using pacifiers at the time of sleep, the importance of educating secondary caregivers and neonatology practitioners on the importance of "back to sleep," and strategies to reduce the incidence of positional plagiocephaly associated with supine positioning. This statement reviews the evidence associated with these and other SIDS-related issues and proposes new recommendations for further reducing SIDS risk.

Habituation of arousal responses after intermittent hypercapnic hypoxia in piglets

RATIONALE

Clinical studies have demonstrated arousal deficits in infants suffering obstructive sleep apnea, and some infant deaths have been attributed to such an arousal deficit.

OBJECTIVES

To evaluate whether arousal deficits can be induced by intermittent asphyxia during normal development.

METHODS AND MEASUREMENTS

Young piglets were exposed to intermittent hypercapnic hypoxia for 4 days from age 9.55 +/- 0.5 days. Arousal responses were compared between control animals and animals exposed to intermittent hypercapnic hypoxia. Outcome measures included time to arouse after onset of the respiratory stimulus and frequency of arousals during recovery.

MAIN RESULTS

Arousal deficits emerged after successive exposures to hypercapnic hypoxia on Day 1, and were exacerbated on Day 4, although after overnight recovery, the deficit only became evident during the second and subsequent episode of hypercapnic hypoxia. On Day 1, time to arouse increased from 16.9 +/- 7.1 seconds in the first epoch to 41.7 +/- 28.6 seconds in the fourth epoch (p = 0.004 between cycles, one-way analysis of variance). In the recovery periods after hypercapnic hypoxia, there were 64% fewer arousals than baseline on Day 1 and 90% fewer arousals on Day 4. Respiratory effort, measured by VT across 10 breaths before the arousal, increased from 25.7 +/- 7.6 on Day 1 to 29.1 +/- 6.8 ml/kg on Day 4 (p < 0.001, two-way analysis of variance, Day 4 vs. Day 1, respectively).

CONCLUSIONS

These studies demonstrate that acute and chronic arousal deficits can be induced by intermittent asphyxia, on a background of otherwise normal postnatal development.

Evaluation of rebreathing potential on bedding for infant use

BACKGROUND

Rebreathing is thought to be associated with sudden infant death syndrome (SIDS). The aim of the present study was to evaluate the rebreathing potential of different types of Japanese infant bedding.

METHODS

The rebreathing potential of various combinations of infant bedding was measured using a mechanically simulated breathing model. The types of bedding included five types of mattresses, four types of o-nesyo sheets (waterproof sheets) and a towel. The half-life of the expiratory CO2 concentration, t1/2-value was calculated as the index of the rebreathing potential. The softness of the bedding was also measured.

RESULTS

There was a moderate proportional correlation between the t1/2-value and the softness (correlation coefficient = 0.509). When a new hard infant mattress was used, the t1/2-values were 13.6-14.1 s, and when o-nesyo sheet was added, the values were 14.1-16.2 s. When other mattresses were used with the o-nesyo sheet, the values were 14.1-19.2 s. Adding a towel onto the bedding, the t1/2-value (18.5-22.3 s) was prolonged without exception.

CONCLUSION

It is difficult to estimate the rebreathing potential of the bedding on the basis its appearance or its softness. All infants should be placed on appropriate bedding in case they turn to a prone-sleeping position. Our recommendations to avoid rebreathing are as follows: (i) a new hard mattress specifically designed for babies should be used; (ii) a towel should not be used; (iii) an o-nesyo sheet may be used with a new hard infant mattress if necessary.

Effect of a sudden infant death syndrome risk reduction education program on risk factor compliance and information sources in primarily black urban communities

BACKGROUND

In the US, a higher incidence of sudden infant death syndrome (SIDS) and a slower decline in the incidence of SIDS has been found among blacks when compared with white infants. The continued racial disparity in SIDS is thought to be attributable to lack of compliance with SIDS risk reduction recommendations.

OBJECTIVES

To better understand the disparities in SIDS risk reduction behaviors, we sought to study compliance and information sources related to SIDS among primarily black communities in a city with a high SIDS incidence rate before and after a targeted educational campaign.

DESIGN

Pre- and post-SIDS Risk Reduction Education Program telephone surveys were performed in targeted Chicago communities with at least 86% blacks. Data collection for Survey 1 was from September 22 to November 4, 1999. Data collection for Survey 2 was from November 17, 2001, to January 12, 2002, 24 months after the aggressive implementation of a comprehensive, ethnically sensitive risk reduction program.

RESULTS

Survey 1 analyzed data from 480 mothers with an infant <12 months of age (327 black, 66 white, and 87 Hispanic) and Survey 2 had 472 mothers (305 black, 77 white, and 90 Hispanic). The incidence of nighttime prone sleeping at Survey 1 was 25% among black respondents, 17% in whites, and 12% in Hispanics and decreased (but not significantly) among all groups by Survey 2. Overall, in Survey 2 compared with Survey 1, fewer mothers reported putting their infants on an adult bed, sofa, or cot both during the day and at night, with the biggest change seen in black mothers for daytime naps. Despite the same educational initiative, blacks increased the use of pillows, stuffed toys, and soft bedding in the sleep environment as compared with whites. More mothers in Survey 2 than in Survey 1 said that they noticed their infants sleeping on their back during the newborn hospitalization. Significantly more black and white mothers in Survey 2 compared with Survey 1 reported that a doctor or nurse had told them what the best position was for putting their infants to sleep, and all 3 groups said that the health care providers indicated that placing the infant on its back was the best sleep position. In examining the relationship between information sources and SIDS risk behaviors, among all groups observation of sleep position in hospital had no effect on behavior after newborn discharge; however, specific instruction by a nurse or doctor in the hospital about how to properly place the infant for sleep influenced behavior after the mother left the hospital.

CONCLUSIONS

The Surveys indicate the greatest impact of the SIDS risk factor educational initiative targeted at black communities was changing behaviors regarding safe sleep locations by reducing the incidence of infants placed for nighttime and daytime sleep in adult beds, sofas, or cots. Although these data indicate considerable progress as a result of the targeted educational initiative, our findings suggest that cultural explanations for specific infant care practices must be more clearly understood to close the gap between SIDS risk factor compliance and apparent knowledge about SIDS risk factors.

Sudden infant death syndrome: overview and update

The past decade and a half has seen marked changes in the epidemiology of sudden infant death syndrome (SIDS). The avoidance of certain risk factors such as sleeping prone and cigarette smoke exposure has resulted in the death rate falling dramatically. Careful evaluation of environmental factors and endogenous characteristics has led to a greater understanding of the complexities of the syndrome. The development and implementation of death scene and autopsy protocols has led to standardization in approaches to unexpected infant deaths with increasing diagnoses of accidental asphyxia. Despite these advances, there is still confusion surrounding the diagnosis, with deaths being attributed to SIDS in many communities and countries where death scene investigations and autopsies have not been conducted. The following review provides a brief overview of the historical background, epidemiology, pathology, and pathogenesis of SIDS. Contentious issues concerning the diagnosis and current problems are discussed. Despite calls to abandon the designation, SIDS remains a viable term for infants who die in their sleep with no evidence of accident, inflicted injury, or organic disease after a full investigation has been conducted according to standard guidelines.

Medial smooth muscle thickness in small pulmonary arteries in sudden infant death syndrome revisited

Increased relative medial thickness (RMT) of smooth muscle in small pulmonary arteries, peripheral extension of smooth muscle into the alveolar wall arteries, and right ventricular hypertrophy (RVH), in response to purported prolonged hypoxia, have been reported in sudden infant death syndrome (SIDS). Prone sleep position, an important risk factor for SIDS, predisposes infants to hypoxia from airway obstruction or rebreathing. Since publication of the earlier pulmonary artery studies, the SIDS definition has been expanded, and sudden infant death investigational protocols have been implemented. Our aims in this study were to (1) compare RMT in preacinar arteries (PA), intra-acinar arteries accompanying small airways (SIA), and alveolar wall arteries (AW) in SIDS infants and controls; (2) correlate RMT with postmortem variables; (3) determine if peripheral extension occurred more often in SIDS infants than in controls; and (4) determine if RVH occurred in SIDS. Movat-stained sections from standardized tissue blocks taken prospectively from the apex of the right upper lobe from 88 SIDS cases and 17 controls were evaluated using a computer-assisted digitizing system with images obtained from a microscope with an attached video camera. When adjusted for age, the RMT values for the SIA arteries were significantly greater in controls, while the PA and AW arteries were not statistically different between the SIDS cases and controls. Peripheral medial smooth muscle extension did not differ between the groups, and RVH was not seen in SIDS cases. Given the recent identification of brain stem abnormalities interfering with protective cardiorespiratory responses against acute life-threatening hypoxia perhaps precipitated by prone sleeping, our data suggest that SIDS is an acute event not preceded by recurrent or prolonged apnea and hypoxia.

Rebreathing potential of infant mattresses and bedcovers

OBJECTIVE

To establish the CO2 dispersion and retention properties of some mattresses and bed coverings commercially available in Australia.

METHODS

Five mattresses were studied in (i) an in vivo model in which an infant's head was covered by a headbox, rebreathing was allowed to occur, and the final steady state CO2 concentration was measured; and (ii) an in vitro model in which 5% CO2 in a headbox was allowed to disperse, and the time taken for the concentration to reach 1% was measured. Five types of bedcover were studied in (i) an in vivo model in which an infant's head was covered by a bedcover and the final steady state CO2 concentration was measured; and (ii) an in vitro model in which 5% CO2 under a bedcover was allowed to disperse, and the time taken for the concentration to reach 1% was measured.

RESULTS

The steady state CO2 concentrations ranged from 0.6% to 3.0% for the mattresses (P < 0.05). The time for CO2 to disperse ranged from 5.5 min to 30.4 min (P < 0.05). Steady state CO2 concentrations ranged from 2.5% to 3.6% for the bedcoverings (P > 0.05). The time for CO2 to disperse ranged from 5.4 min to 7.7 min (P > 0.05).

CONCLUSIONS

Some commercial cot mattresses and bedcoverings allow high concentrations of CO2 to accumulate in rebreathing environments. Some mattress types studied were more diffusive to CO2, whereas there was no difference between the bedcovers studied. This may have implications for vulnerable infants at risk of sudden infant death syndrome.

Cosleeping and sudden unexpected death in infancy

CONTEXT

The practice of infants cosleeping with adults has long been the subject of controversy. Autopsy findings in cases of sudden infant death syndrome (SIDS) are usually indistinguishable from those found with unintentional or intentional suffocation, and the determination of the cause of death in cases of sudden unexpected death in infancy is often based on investigative findings and the exclusion of natural or traumatic causes.

OBJECTIVE

To further elucidate the risk of cosleeping.

METHODS

We reviewed 58 cases of sudden unexpected infant deaths. Cases were excluded if there was any significant medical history or evidence of trauma or abuse.

RESULTS

Twenty-seven of the infants were cosleeping. Eleven of these cases had been previously diagnosed as SIDS, and in 7 cases parental intoxication was documented.

CONCLUSION

Our findings support recent studies that suggest that cosleeping or placing an infant in an adult bed is a potentially dangerous practice. The frequency of cosleeping among cases diagnosed as SIDS in our study suggests that some of these deaths may actually be caused by mechanical asphyxia due to unintentional suffocation by the cosleeping adult and/or compressible bedding materials.

A review of the anatomy of the upper airway in early infancy and its possible relevance to SIDS

BACKGROUND

Since the danger of prone sleeping in the first 6 months of life has been publicised, there has been a dramatic and consistent reduction in the incidence of sudden infant death syndrome (SIDS). However, unexpected infant deaths and apparent life-threatening events (ALTEs) continue to occur that are clearly not associated with known epidemiological risk factors.

AIMS

To review the unique features of the anatomy and function of the upper airway of the young infant which contribute to increased vulnerability to hypoxia in this age group. We discuss the clinical identification of those infants at risk of obstruction or restriction of the upper airway and the management of the 'at risk' infant.

CONCLUSIONS

In the era after the "back to sleep" campaigns, it is likely that an increasing proportion of cases of ALTEs and SIDS will be related to obstruction or limitation of upper airway size leading to sleep hypoxia/asphyxia. This type of problem may be anticipated by evaluation and investigation of infants with signs or a clinical history consistent with possible upper respiratory tract compromise, including micrognathia.

Association between sudden infant death syndrome and prone sleep position, bed sharing, and sleeping outside an infant crib in Alaska

OBJECTIVE

To determine the contribution of prone sleeping, bed sharing, and sleeping outside an infant crib to sudden infant death syndrome (SIDS).

METHODS

We conducted a retrospective descriptive study of all SIDS cases in Alaska from January 1, 1992, through December 31, 1997. Reviewed data sources included maternal and infant medical records, autopsy reports, birth and death certificates, police and state trooper death scene investigations, and occasionally home interviews.

RESULTS

The death certificate identified SIDS as a cause of death for 130 infants (cause-specific infant mortality rate: 2.0 per 1000 live births). Among infants for whom this information was known, 113 (98%) of 115 were found in the prone position, sleeping outside an infant crib, or sleeping with another person. By contrast, 2 (1.7%) were found alone and supine in their crib (1 of whom was found with a blanket wrapped around his face). Of 40 infants who slept with a parent at the time of death, only 1 infant who slept supine with a non-drug-using parent on an adult nonwater mattress was identified.

CONCLUSION

Almost all SIDS deaths in Alaska occurred in association with prone sleeping, bed sharing, or sleeping outside a crib. In the absence of other risk factors, SIDS deaths associated with parental bed sharing were rare.

Examination of state regulations regarding infants and sleep in licensed child care centers and family child care settings

BACKGROUND

Twenty percent of sudden infant death syndrome (SIDS) occurs in child care settings. Although the incidence of SIDS in the United States has decreased with increased awareness of the risks of prone infant sleeping, smoke exposure, soft bedding, and unsafe sleep environments, avoidance of these risk factors is not universally practiced in child care settings. Advocacy through state child care regulatory agencies and legislative bodies may be effective in more widespread awareness and avoidance of risk factors.

OBJECTIVE

To determine what individual state regulations for licensed child care centers and family child care settings exist regarding: 1) sleep positions for infants under 6 months old, 2) crib safety, 3) bedding safety, and 4) smoking in the facilities.

DESIGN

A descriptive survey of regulations for licensed child care centers and family child care settings in the 50 states and the District of Columbia.

RESULTS

Fifteen states use regulations adopted before publication of the first policy statement of the American Academy of Pediatrics on infant sleep position and SIDS in 1992. Six states require child care centers to place infants nonprone. Sixty-three percent of states require cribs in child care centers to meet at least 1 safety standard, and 45.1% require this in family child care homes. Six states have provisions limiting the use of soft bedding in child care centers, and 4 have such bans for family child care homes. Seventy-one percent of states prohibit smoking in child care centers during hours of operation; 17% of states have similar requirements for family child care homes.

CONCLUSIONS

Many states use child care regulations that were written before the initial policy statements of the American Academy of Pediatrics regarding safe sleep environments for infants. Even those more recently adopted regulations do not adequately address sleep safety for infants. Pediatricians need to become more proactive in promoting safety regulations in child care. Adoption of new regulations can aid in education of child care providers and, thus, improve the safety for infants in child care.

Sleep position and the use of soft bedding during bed sharing among African American infants at increased risk for sudden infant death syndrome

Soft bedding increases the risk for death among prone infants. We compared the softness of beds and bedding and infant sleep position for infants sleeping alone and for those bed sharing.

STUDY DESIGN

Questionnaires were used to record the bedding and sleep practices of 218 consecutive African American infants. Enrollment was prospective. Mechanical models were used in the homes of a subgroup to measure the softness of bedding and its propensity to cause rebreathing. Results were compared by using the Student t test, Mann-Whitney U test, and chi(2) analysis.

RESULTS

In a cross-sectional sample of infants, at 8.2 +/- 3.3 weeks of age, 61% (133 of 218) had bed shared > or =1 of the previous 14 nights and 48.6% (106 of 218) had bed shared the night before. Breast-feeding rates were not different for bed sharers and those sleeping alone. The rates of maternal smoking for both groups were low (13.6% vs 11.8%). Comforters, pillows, and waterbeds were more commonly used beneath bed-sharing infants. Bed sharers were twice as likely to habitually be placed prone for sleep (18% vs 9%). In the subgroup studied in their homes (13 bed sharing, 19 alone), the shared beds were softer (P <.0001) and could cause more rebreathing (P =.007).

CONCLUSIONS

Infants at increased risk for sudden infant death syndrome, by sociodemographic criteria, who also bed share are more likely to sleep prone and to use softer beds. These findings may explain part of the risk associated with bed sharing among US infants, a risk that appears to be independent of the effects of maternal smoking.

Simultaneous sudden infant death syndrome: a proposed definition and worldwide review of cases

Epidemiologic studies of sudden infant death syndrome (SIDS), the leading cause of death of infants during the postperinatal period (7-365 days), have mainly focused on the deaths of single infants. Simultaneous sudden infant death syndrome (SSIDS), the death of a pair of twins occurring at the same time, has received limited attention within the medical community. To the authors' knowledge, this article is the first to describe the 41 SSIDS cases cited in the world literature from 1900 to 1998 by the location of death, a summary of the circumstances surrounding the deaths, and evaluation of these cases in terms of a proposed definition of SSIDS. This evaluation critiques whether the 41 pairs of SSIDS cases adhere to a newly proposed definition of SSIDS. Twin infant deaths must meet all three criteria to be considered SSIDS. The study found that only 12 pairs of twins met all three criteria (29.2%), nine pairs met two criteria (21.9%), alternative cause of death was offered in five pairs of twins (12.1%) and in the remaining 15 pairs (36.6%), only limited information was available; therefore, no conclusions could be reached.

Intrathoracic petechiae in sudden infant death syndrome: relationship to face position when found

Previous studies have not addressed the relationship of intrathoracic petechiae (IP) to the position of the face when a caretaker finds a victim of sudden infant death syndrome (SIDS). The aims of this retrospective study were to determine (1) the rate of the facedown position in SIDS (not to be confused with the prone body position), (2) if the facedown position occurred more frequently among SIDS victims with intrathoracic petechiae than those without petechiae, and (3) if the facedown position occurred more frequently among cases with more severe petechial hemorrhage of the thymus. We selected 199 SIDS cases from the San Diego SIDS Research Project database and grouped them as IP-present and IP-absent. Each case was analyzed with regard to the face position when found unresponsive or dead. Among these 199 cases, 37% were found face-down, which represents 51% of the 142 cases found prone. The two groups were similar with respect to age, sex, and rate of premature birth. Thirty-nine percent (39%) of the IP-present group and 9% of the IP-absent group were found in the facedown position (P = 0.057; 95% confidence interval for the difference = 0.3%, 40%). Cases were also grouped by severity of thymic petechiae and analyzed regarding face position. Neither age nor the facedown position was associated with greater severity of thymic petechiae. The wide confidence interval yielded by our analysis of IP limits our ability to clarify the precise pathophysiologic role of external oronasal obstruction in SIDS. While it remains possible that a subset of SIDS cases occur as a result of external obstruction, we are unable to generalize its importance. Internal airway obstruction and rebreathing with terminal gasping, both of which have been documented in sudden infant death, remain other possible scenarios leading to the production of IP.

Computational simulation of accumulation of expired air in the infant cot

Accumulation and re-breathing of CO2 in expired air has been suggested as one possible explanation for the strong association between prone sleeping position and sudden infant death syndrome (SIDS). This preliminary study applying a modern computational fluid dynamics (CFD) program to simulate the aerodynamics in an infant cot supports the idea that accumulation of expired air may occur in the prone position. The literature dealing with the potential association between re-breathing of accumulated CO2 and SIDS is briefly reviewed.

CLINICAL REVIEW ARTICLE: Is changing the sleep environment enough? Current recommendations for SIDS

Sudden infant death syndrome (SIDS or cot death) was the major cause of post-neonatal infant death in many countries in the late 1970s and 1980s. There is now very strong evidence that public intervention campaigns targeting the prone sleeping position, which had been identified by epidemiological studies as a major risk factor, were followed by substantial falls in the rate of SIDS. In the present review we discuss the evidence on which current recommendations for the prevention of SIDS are based. The prone sleeping position is now clearly causally associated with SIDS. Further reductions in SIDS may be produced by recommending the back sleeping position as opposed to the side position. Maternal smoking in pregnancy and bed sharing by infants of mothers who smoke are also strongly associated with SIDS, but have been harder to influence. Paternal smoking has also been implicated, although the magnitude of the reported risk is small. Finally, breastfeeding, pacifier use and having the infant sharing the parents bedroom, but not the bed, may also reduce risk. Continued reductions in SIDS mortality will require innovative public health education to target these major risk factors, while building on the "back to sleep" approach.

Prevalence of SIDS risk factors: before and after the "Back to Sleep" campaign in North Dakota Caucasian and American Indian infants

The objective of this study was to compare rates of infant sleeping position and other risk factors for sudden infant death syndrome from 1991 before the "Back to Sleep" campaign to rates in 1998 after the campaign. We used a cross-sectional risk factor prevalence study of risk factors for the years 1991 and 1998. In North Dakota the prevalence rates of prone sleeping declined 72% for American Indian infants and 62% for Caucasian infants. We were unable to identify a corresponding decline in SIDS in North Dakota for this time period. The relationship between sleeping position and SIDS may be more complex in rural and frontier settings and in American Indian populations than in urban and majority populations. The generalizability of this study is limited by the rural setting and small sample size. Longer term surveillance and additional reports from sites with pre "Back to Sleep" data as a baseline for both SIDS rates and sleeping position will be important to clarify the rate of prone sleeping position and SIDS.

Potential to prevent carbon dioxide rebreathing of commercial products marketed to reduce sudden infant death syndrome risk

OBJECTIVE

Rebreathing of exhaled air is one proposed mechanism for the increased risk for sudden infant death syndrome among prone sleeping infants. We evaluated how carbon dioxide (CO(2)) dispersal was affected by a conventional crib mattress and 5 products recently marketed to prevent prone rebreathing.

SETTING

Infant pulmonary laboratory.

EQUIPMENT

An infant mannequin with its nares connected via tubing to an 100-mL reservoir filled with 5% CO(2). The sleep surfaces studied included: firm mattress covered by a sheet, Bumpa Bed, Breathe Easy, Kid Safe/Baby Air, Halo Sleep System, and Sleep Guardian. The mannequin was positioned prone face-down or near-face-down. The sleep surfaces were studied with the covering sheet taut, covering sheet wrinkled, and with the mannequin arm positioned up, near the face.

MEASUREMENTS

. We measured the fall in percentage end-tidal CO(2) as the reservoir was ventilated with the piston pump. The half-time for CO(2) dispersal (t(1/2)) is an index of the ability to cause or prevent rebreathing.

RESULTS

Compared with the face-to-side control, 5 of 6 surfaces allowed a significant increase in t(1/2) in all 3 prone scenarios. The firm mattress and 4 of the 5 surfaces designed to prevent rebreathing consistently allowed t(1/2) above thresholds for the onset of CO(2) retention and lethal rebreathing in an animal model (J Appl Physiol. 1995;78:740).

CONCLUSIONS

With very few exceptions, infants should be placed supine for sleep. For infants placed prone or rolling to the prone position, significant rebreathing of exhaled air would be likely on all surfaces studied, except one.

Sudden infant death syndrome, child sexual abuse, and child development

Since the introduction of the Back to Sleep Campaigns, there has been a dramatic reduction in sudden infant death syndrome in this country. Steven Blatt and Victoria Meguid review the literature surrounding sleep position. Investigators have continued efforts to find other modifiable risk factors of sudden infant death syndrome. A prospective study of more than 33,000 neonates found a link between a prolonged QT electrocardiogram interval and sudden infant death syndrome. Also discussed are investigations seeking to explain the relationship between smoking and sudden infant death syndrome. Ann Botash, Florence Jean-Louis and Mongkae Ploy Siripornsawan review the latest thinking on genital warts and their relation to specific viral etiologies and child sexual abuse. Other symptoms and signs of sexual abuse are the focus of a number of articles that can help the practitioner care for these unfortunate children. Catherine Church reviews medication options for children diagnosed with pervasive developmental disorders or autism spectrum disorders. Finally, in this article, risperidone, fluoxetine and naltrexone are reviewed.

Effects of sleep position on infant motor development

BACKGROUND

As a result of the American Academy of Pediatrics' recommendation that healthy infants be placed on their side or back for sleep, the percentage of infants sleeping prone has decreased dramatically. With the increase in supine sleeping, pediatricians have questioned if there are differences in the rate of acquisition of early motor milestones between prone and supine sleeping infants.

METHODS

To examine this question, we performed a prospective, practice-based study of healthy term infants. Infants were recruited before the age of 2 months. Parents were asked to record infant sleep position and awake time spent prone until 6 months of age. A developmental log was used to track milestones from birth until the infant was walking. Age of acquisition of eight motor milestones was determined, and the mean ages of milestone attainment of prone and supine sleepers were compared.

RESULTS

Three hundred fifty-one infants completed the study. Prone sleepers acquired motor milestones at an earlier age than supine sleepers. There was a significant difference in the age of attainment of rolling prone to supine, tripod sitting, creeping, crawling, and pulling to stand. There was no significant difference in age when infants walked.

CONCLUSIONS

The pattern of early motor development is affected by sleep position. Prone sleepers attain several motor milestones earlier than supine sleepers. However, all infants achieved all milestones within the accepted normal age range. Pediatricians can use this information to reassure parents. This difference in milestone attainment is not a reason to abandon the American Academy of Pediatrics' sleep position recommendations.