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Preterm EEG: A Multimodal Neurophysiological Protocol
Published on: February 18, 2012
Car seat test for preterm infants: comparison with polysomnography
Dawn E Elder1, Letitia Russell, Deidre Sheppard
1Department of Paediatrics, WSMHS, PO Box 7343, Wellington, New Zealand. dawn.elder@otago.ac.nz
Insights
Preterm infants show respiratory instability in both cots and car seats. Observed car seat tests are not fully reliable for detecting adverse sleep events in these infants.
Area of Science:
- Neonatal care
- Pediatric sleep medicine
- Respiratory physiology
Background:
- Preterm infants are at risk for cardiorespiratory events during sleep.
- Assessing infant safety during sleep outside the hospital, such as in car seats, is crucial before discharge.
- Polysomnography (PSG) is the gold standard for sleep and respiratory monitoring.
Purpose of the Study:
- To monitor preterm infants' respiratory and sleep patterns in both a cot and a car seat.
- To compare observed car seat trials with polysomnography (PSG) findings.
- To evaluate the accuracy of nurse observations versus PSG in detecting adverse events in car seats.
Main Methods:
- A non-randomized controlled trial was conducted in a regional neonatal unit.
- Preterm infants nearing discharge underwent nap polysomnography (PSG) in a cot and a car seat.
- Respiratory and sleep variables, including gastro-oesophageal pH, were measured via PSG. Nurse observations of respiratory distress, apnea, oxygen saturation, and heart rate were also recorded.
Main Results:
- Fewer central apneas and arousals occurred in the cot compared to the car seat (p=0.047 and p=0.024).
- Younger postmenstrual age (PMA) at the time of study predicted failure in both cot and car seat conditions (p=0.022).
- Nurse-observed tests showed low sensitivity for predicting PSG failure but were better at identifying airway obstruction.
Conclusions:
- Immature infants demonstrate respiratory instability when sleeping in both cots and car seats.
- Standard car seat tests may not accurately identify all potential adverse respiratory or sleep events during car seat use.
- Further research is needed to refine methods for assessing infant safety in car seats.
Objectives:
To monitor preterm infants in a cot and a car seat and compare an observed car seat trial with polysomnography (PSG).
Design:
Non-randomised controlled trial.
Setting:
Regional neonatal unit.
Patients:
Preterm infants before discharge.
Interventions:
Nap PSG respiratory and sleep variables were measured including gastro-oesophageal pH. Nurse observations included respiratory distress, apnoea measured by apnoea alarm, oxygen saturation and heart rate. Infants were studied supine in a cot and then in a car seat. Nursing observations were compared with PSG during the car seat trial only. Criteria for failure of the PSG and observed tests were predefined.
Main Outcome Measures:
Difference in respiratory instability between cot and car seat. Concurrence regarding failure of the car seat trial between nurse-observed data and PSG.
Results:
20 infants (median gestation 33 weeks (range 28-35 weeks; median postmenstrual age (PMA) at study 36.5 weeks (range 35-38 weeks)) were studied. There were sufficient car seat data on 18 infants for comparison. There were fewer central apnoeas and arousals in the cot than the car seat (p = 0.047 and p = 0.024, respectively). Airway obstruction was not more common in the car seat. Younger PMA at time of study predicted failure in both car seat (p = 0.022) and cot (p = 0.022). The nurse-observed test had low sensitivity for predicting PSG failure but more accurately predicted airway obstruction on PSG.
Conclusions:
Immature infants exhibit respiratory instability in cots and car seats. A car seat test does not accurately detect all adverse events during sleep in the seat.
