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Effect of time and body position on ventilation in premature infants
Judith Hough1,2, Anthony Trojman1, Andreas Schibler2
1School of Physiotherapy, Australian Catholic University, Banyo, Australia.
Insights
Regularly repositioning preterm infants with respiratory dysfunction improves lung function. For infants on ventilatory support, lung function peaks at 2 hours and remains elevated for 4 hours post-repositioning.
Area of Science:
- Neonatal Medicine
- Pediatric Pulmonology
- Physiological Measurement
Background:
- Infants with respiratory dysfunction often require repositioning to enhance lung function.
- Optimal frequency for position changes to improve infant lung function remains unclear.
- This study investigates lung function changes over time following repositioning in preterm infants.
Purpose of the Study:
- To quantify changes in lung function over time after repositioning in preterm infants.
- To compare lung function changes in infants receiving different forms of respiratory support versus spontaneously breathing infants.
- To determine the optimal timing for position changes to maximize lung function benefits.
Main Methods:
- Utilized Electrical Impedance Tomography (EIT) to measure end-expiratory level (EEL) and ventilation distribution.
- Measurements were taken at 30 minutes, 2 hours, and 4 hours post-repositioning.
- Infants were repositioned into prone, quarter turn from prone, or supine positions; physiological parameters were also recorded.
Main Results:
- Sixty preterm infants were studied.
- Infants on mechanical ventilation or CPAP showed improved ventilation homogeneity at 2 hours, sustained at 4 hours.
- Spontaneously breathing infants exhibited improved homogeneity at 2 hours and improved global EEL at 4 hours.
Conclusions:
- Regional ventilation distribution is time-dependent and influenced by body position changes.
- Infants on ventilatory support experience a peak in lung function 2 hours post-repositioning, lasting up to 4 hours.
- Repositioning is a beneficial intervention for improving lung function in infants requiring ventilatory support.
Background:
Infants with respiratory dysfunction undergo regular position changes to improve lung function however it is not known how often a position change should occur. This study measured changes in lung function occurring over time after repositioning in preterm infants.
Methods:
Changes in end-expiratory level (EEL) and ventilation distribution were measured 30 mins, 2 h, and 4 h after repositioning into either prone, quarter turn from prone, or supine using Electrical Impedance Tomography (EIT). Physiological measurements were also taken.
Results:
Sixty preterm infants were included in the study. Infants receiving respiratory support (mechanical ventilation or continuous positive airway pressure (CPAP)) had improved ventilation homogeneity after 2 h (P < 0.01), maintained at 4 h. Spontaneously breathing infants had improved homogeneity at 2 h (P < 0.01) and improved global EEL after 4 h (P < 0.01) whereas infants receiving CPAP demonstrated an improved global EEL at 2 h (P < 0.01).
Conclusion:
Regional ventilation distribution is influenced by time independent of changes due to body position. Differences exist between infants on ventilatory support compared with those who are spontaneously breathing. Infants receiving ventilatory support have a physiological peak in lung function after 2 h which remains above baseline at 4 h. A change in body position facilitates an improvement in lung function in infants on ventilatory support.
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