Sudden unexpected death study underlines risks of infants sleeping in sitting devices

Mechanical environment influences muscle activity during infant rolling

An infant's musculoskeletal and motor development is largely affected by their environment. Understanding how different mechanical environments affect an infant's movements and muscle use is necessary to inform the juvenile products industry and reduce incidents involving inclined nursery products each year. The purpose of this study was to determine how the coordinated movements and corresponding muscle activation patterns are affected by different mechanical environments, specifically the back incline angle. Thirty-eight healthy infants (age: 6.5 ± 0.7 months; 23 M/15 F) were enrolled in this IRB-approved in-vivo biomechanics study. Surface electromyography sensors recorded muscle activity of the erector spinae, abdominal muscles, quadriceps, and hamstrings while infants rolled in five different mechanical environments: a flat surface and four device configurations representing a range of inclines infants are commonly exposed to. Coordinated movements were determined using video. In all configurations featuring an inclined seatback angle, infants experienced significantly higher erector spinae muscle activation and significantly lower abdominal muscle activation compared to the flat surface. Infants also exhibited a different coordinated movement featuring spinal extension and a pelvic thrust in the inclined device configurations that was not previously observed on the flat surface alone. Understanding how infants coordinate their movements and use their muscles during rolling in different inclined environments provides more insight into motor development and may inform the juvenile products industry. Many factors impact an infant's movements, therefore future work should explore how other environmental interactions influence an infant's movements and muscle activation, particularly for rolling.

Car Seat Tolerance Screening in the Neonatal Intensive Care Unit: Failure Rates, Risk Factors, and Adverse Outcomes

OBJECTIVE

To characterize the epidemiology of Car Seat Tolerance Screening (CSTS) failure and the association between test failure and all-cause 30-day postdischarge mortality or hospital readmission in a large, multicenter cohort of preterm infants receiving neonatal intensive care.

STUDY DESIGN

This retrospective cohort study used the prospectively collected Optum Neonatal Database. Study infants were born at <37 weeks of gestation between 2010 and 2016. We identified independent predictors of CSTS failure and calculated the risk-adjusted odds of all-cause 30-day mortality or hospital readmission associated with test failure.

RESULTS

Of 7899 infants cared for in 788 hospitals, 334 (4.2%) failed initial CSTS. Greater postmenstrual age at testing and African American race were independently associated with decreased failure risk. Any treatment with an antacid medication, concurrent use of caffeine or supplemental oxygen, and a history of failing a trial off respiratory support were associated with increased failure risk. The mean adjusted post-CSTS duration of hospitalization was 3.1 days longer (95% CI, 2.7-3.6) among the infants who failed the initial screening. Rates of 30-day all-cause mortality or readmission were higher among infants who failed the CSTS (2.4% vs 1.0%; P = .03); however, the difference was not significant after confounder adjustment (OR, 0.38; 95% CI, 0.11-1.31).

CONCLUSION

CSTS failure was associated with longer post-test hospitalization but no difference in the risk-adjusted odds for 30-day mortality or hospital readmission. Whether CSTS failure unnecessarily prolongs hospitalization or results in appropriate care that prevents adverse postdischarge outcomes is unknown. Further research is needed to address this knowledge gap.

Hazards Associated with Sitting and Carrying Devices for Children Two Years and Younger

OBJECTIVE

To analyze reported mechanisms of injury and characterize risk factors for infants and young children ≤ 2 years of age who died in sitting and carrying devices.

STUDY DESIGN

A retrospective review of deaths involving sitting and carrying devices (car seats, bouncers, swings, strollers, and slings) reported to the US Consumer Product Safety Commission between 2004 and 2008.

RESULTS

Of the 47 deaths analyzed, 31 occurred in car seats, 5 in slings, 4 each in swings and bouncers, and 3 in strollers. The reported elapsed time between the last time a child was seen by a caregiver and found deceased varied greatly, with a mean of 26 minutes in slings; 32 minutes in strollers; 140 minutes in car seats; 150 minutes in bouncers; and 300 minutes in swings. The cause of death was asphyxiation in all cases except one. Fifty-two percent of deaths in car seats were attributed to strangulation from straps; the others were attributed to positional asphyxia.

CONCLUSION

Infants and children 2 years of age and younger should be properly restrained and not be left unsupervised in sitting and carrying devices. Car seats should not be used as sleeping areas outside of the vehicle, and children should never be in a car seat with unbuckled or partially buckled straps. Infants in slings should have their faces visible and above the edge of the sling, should not have their faces covered by fabric, and their chins should not be compressed into their chests.

Sudden unexpected death in infancy: biological mechanisms

Sudden unexpected death in infancy (SUDI) covers both explained and unexplained deaths. Unexplained cases or SIDS are likely to have multiple neural mechanisms contributing to the final event. The evidence ranges from subtle physiological signs related to autonomic control, to findings at autopsy of altered neurotransmitter systems, including the serotonergic system, a network that has an extensive homeostatic role in cardio-respiratory and thermoregulatory control. Processes may be altered by the vulnerability of the infant due to age, poor motor ability, or a genetic predisposition. The fatal event may occur in response to an environmental stress. A single final physiological route to death seems unlikely. An understanding of the reasons for explained SUDI also reminds us that a thorough investigation is required after each death occurs.