Stability of the infant car seat challenge and risk factors for oxygen desaturation events

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.

Predictors of Persistent Infant Car Seat Challenge Failure

BACKGROUND

Premature and other at-risk infants can experience cardiorespiratory problems when positioned in their car seats. The American Academy of Pediatrics recommends that all premature and at-risk infants undergo a period of observation in their car seat to monitor for apnea, bradycardia, and oxygen desaturation before hospital discharge. This Infant Car Seat Challenge (ICSC) is used to determine readiness for infant travel in a car seat. Infants failing the ICSC are discharged home in car beds and referred for a follow-up screen in the outpatient clinic.

PURPOSE

The purpose of this study was to identify predictors for infants failing the follow-up ICSC after hospital discharge.

METHODS/SEARCH STRATEGY

A retrospective, cross-sectional study design was used to examine charts of 436 infants referred from across New England, to Boston Children's Hospital's, Center for Healthy Infant Lung Development clinic between August 2008 and May 2015 for a follow-up ICSC.

FINDINGS/RESULTS

Infants who failed the follow-up ICSC had statistically significant lower weights (0.27 ± 0.14 kg, difference ± standard error, P = .03) and younger postmenstrual ages (0.9 ± 0.4 weeks, P = .03). History of a cardiac condition (odds ratio, 3.6; 95% confidence interval, 1.5-8.5; P = .005) and respiratory illness (odds ratio, 2.1; confidence interval, 1.1 to 4.2; P = .03) were significant predictors of ICSC failure.

IMPLICATIONS FOR PRACTICE

A follow-up ICSC is recommended for the safe transition of infants from a car bed to a car seat.

IMPLICATIONS FOR RESEARCH

Further research is needed to investigate the causes of ICSC failure among high-risk infant populations.

Assessment of cardiorespiratory stability using the infant car seat challenge before discharge in preterm infants (<37 weeks' gestational age)

Preterm infants younger than 37 weeks corrected gestational age are at increased risk for abnormal control of respiration. The infant car seat challenge has been used as a screening tool to ensure cardiorespiratory stability before discharging preterm infants from many hospitals in Canada. While it is clear that infants placed in a car seat are more likely to experience oxygen desaturation and/or bradycardia than when they are supine, neither positioning predicts an adverse neurodevelopmental outcome or mortality post-discharge. A review of the literature yielded insufficient evidence to recommend routine use of the infant car seat challenge as part of discharge planning for preterm infants. This finding has prompted a change in recommendation from a previous Canadian Paediatric Society position statement published in 2000.

Screening for cardiopulmonary events in neonates: a review of the infant car seat challenge

The infant car seat challenge (ICSC), or period of observation in a car safety seat before discharge to monitor for episodes of apnea, bradycardia and desaturation, is one of the most common tests performed on preterm neonates in the United States. However, the utility of the ICSC to identify infants at risk for adverse cardiopulmonary events in the car seat remains unclear. Minimal evidence exists to guide clinicians in performance of this test including appropriate inclusion criteria and failure criteria. In this article, the origins of the ICSC are discussed as well as potential etiologies of desaturations and bradycardia in the car seat position. Current literature on implementation, inclusion and failure criteria, incidence of failure and data on the meaning of a 'passed' vs 'failed' ICSC are discussed. Emphasis is made on minimizing time in car seats and seated devices given concern over the risk of desaturations.

Alteration in regional tissue oxygenation of preterm infants during placement in the semi-upright seating position

We investigated whether the cerebral (rSO2-C %) and renal (rSO2-R %) tissue oxygenation of preterm infants is altered by repositioning from the supine to semi-upright position for pre-discharge car seat testing. Near-infrared spectroscopy was used to measure rSO2-C and rSO2-R, which were recorded simultaneously with vital signs in 15 preterm infants for 30 minutes in supine, 60 minutes in the semi-upright (at 45 degrees in a car seat), and 30 minutes in the post-semi-upright (supine) position. Changes in rSO2-C and SO2-R were mostly within 1 Standard Deviation (SD) of baseline mean levels in the supine position. Decrease in rSO2-C and rSO2-R (more than 1SD below baseline mean) was recorded in 26.7% and 6.6% of infants respectively, which persisted even after adjustment for variation in heart and respiratory rate, and pulse oximeter measured oxygen saturation (P, 0.0001). Re-positioning the infants from the car seat to supine position was associated with normalization of the rSO2-C. Alteration in rSO2-C and rSO2-R in a car seat was independent from the gestational and post-conception age, weight and presence of anemia. We concluded that approximately one-third of preterm infants show minor reduction of cerebral tissue oxygenation in the semi-upright (car seat) position.

Test-retest reliability of the infant car-seat challenge

OBJECTIVE

To evaluate how a single infant car-seat challenge (ICSC) predicts subsequent respiratory physiology in premature infants.

STUDY DESIGN

Prospective observational study of infants born at <37 weeks gestational age. Subjects underwent three ICSCs and we evaluated clinical characteristics, pass rate, and predictive value of a single ICSC pass.

RESULT

Completed three ICSCs on 60 subjects. Seven failed initial ICSC (11.7%). Those who failed had lower birth weights. Of the 53 that initially passed, 47 passed two subsequent tests (89%). Those who passed an initial test and failed a subsequent test had lower weights at each ICSC.

CONCLUSION

Our results indicate that passing an ICSC is highly predictive of passing subsequent ICSCs. Lower weights at birth and at the time of ICSC were associated with increased risk of failure. We recommend including low birth weight as an inclusion criterion for ICSCs.

A comparison of the infant car seat challenge and the polysomnogram at the time of hospital discharge

OBJECTIVE

The American Academy of Pediatrics recommends all infants born at <37 weeks gestation spend a period of observation in a car seat prior to hospital discharge to assess for apnoea, bradycardia or oxygen desaturation. The most recent Cochrane review suggested further studies to determine if the infant car seat challenge (ICSC) accurately predicts the risk of clinically adverse events. We reviewed our experience with the ICSC and the polysomnogram (PSG) to determine if the ICSC accurately predicts the risk of adverse events when compared with the PSG.

STUDY DESIGN

Retrospective chart review of all infants in our institution who had an ICSC and a PSG between January 2005 and December 2008.

RESULT

785 infants had ICSCs. In addition, 313 infants (56.6%) had an abnormal PSG, even though the vast majority, 158 (88.3%), passed their ICSC. There were no significant differences in gestational age at birth, birth weight, chronological age at study or postmenstrual age at study between infants who either passed or failed the ICSC with those who passed or failed the PSG. The sensitivity of the ICSC was 0.11 and specificity was 0.96. The positive predictive value of the ICSC was 0.77 and the negative predictive value was 0.45.

CONCLUSIONS

The ICSC has a low negative predictive value (0.45) when compared with the PSG as a reference standard for identifying adverse cardiorespiratory events. Although less time consuming and cumbersome than extended polysomnography, the ICSC is not a reliable substitute.

Weight and age as predictors for passing the infant car seat challenge

OBJECTIVE

The American Academy of Pediatrics recommends observation of preterm and at-risk infants in their car seat before hospital discharge to screen for breathing problems. This observation period, which we refer to as the infant car seat challenge (ICSC), is used to determine readiness for travel in a car seat. Infants who fail the ICSC are recommended to travel in a car bed. Limited data exist to identify risk factors for failing the ICSC, and no guidelines are available to facilitate transition from car beds to car seats. The purpose of this study was to determine whether weight and age are predictors for passing the ICSC.

METHODS

This retrospective study evaluated 43 infants referred to the Children's Hospital Boston Center for Healthy Infant Lung Development for a repeat ICSC after initial failure and 37 infants who passed or failed their initial ICSC at the Caritas Saint Elizabeth's Medical Center. Gender, birth weight, gestational age (GA), weight (ICSC weight), corrected GA, and chronological age at time of ICSC were extracted, and logistic regression analysis was performed.

RESULTS

The average GA at birth of infants referred was 35 weeks 2 days (+/-2 weeks 3 days), and almost equal numbers of boys and girls were referred. A majority of infants passed their initial rechallenge (38 [88%] of 43). Infants who failed the repeat challenge were slightly smaller (3327 +/- 927 vs 3913 +/- 936 g) and younger at time of retesting (CGA 40 weeks 5 days vs 42 weeks 5 days; chronological age 39.2 vs 52.2 days). Neither weight nor age at initial or repeat ICSC predicted passing the ICSC.

CONCLUSIONS

This study suggests that ICSC screenings remain the safest method for transitioning preterm infants from a car bed to a car seat.