Page 38 - Physiological based CPAP for preterm infants at birth Tessa Martherus
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Chapter 1
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Table 1. Preterm animal models using CPAP or MV to investigate PEEP strategies in newborn physiology
Study characteristics
PEEP strategy
Outcome Measure
Summary results focussing on CPAP levels
(high levels vs low levels)
Study
Model Mean Pressure age support
Lung aeration prior to the experiment 10 min
8 cmH2O
Intervention
Duration (min)
Mulroone y et al. (31)
Lambs 130- CPAP n=21 136*
5 cmH2O vs 8 cmH2O
360
Blood gas, ventilation parameters
Using 8 cmH2O oxygenation and lung gas volumes were higher. At 8 cmH2O the animals had a lower breathing rate while generating similar tidal volumes
Probyn et al. (33)
Lambs 125 MV n=19
No
0 cmH2O vs 4 cmH2O vs 8 cmH2O vs 12 cmH2O
135
Blood gas, arterial pressure, ventilation and physiological parameters. Oxygenation, PBF, shunting through the ductus arteriosus
Oxygenation improved mostly using PEEP ≥8 cmH2O. Lambs receiving 12cmH2O developed pneumothoraxes
Polglase et al. (36)
Lambs 129 MV n=13 +/- 1
20 min
4 cmH2O
4-6-8-10-8-6-4 cmH2O vs
4 cmH2O
70 min; each level held for 10 min
At PEEP 10 cmH2O PBF lowered due to an increase in pulmonary vascular resistance and increased R-L shunting. High PEEP also impaired cardiovascular function e.g. reduction in heart rate
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