[Effects of the volume of the reservoir bag and the amount of fresh gas flow on FRC during CPAP].
We have examined effects of the volume of the reservoir bag and the amount of fresh gas flow (FGF) on FRC during CPAP with PEEP level of 8 or 11 cmH2O. We used reservoir bags of 4 different volumes (5, 10, 15, 20l). We set up the air way pressure graduation between inspiration and expiration (delta P) by adjusting FGF rate, then we measured delta FRC and other respiratory parameters in 8 volunteers (26.3 +/- 0.8 yo). With the same PEEP level, delta P decreased but FRC increased by increasing FGF rate. When we used a lager reservoir bag, FGF rates which are necessary to set up the minimum delta P decreased during CPAP. We could obtain a larger delta FRC by using a larger reservoir bag compare with a smaller one, at the same delta P using same CPAP level. We should consider not only delta P but also the volume of the reservoir bag to obtain a reasonable and comfortable CPAP.
Tamura
M
M
Department of Anesthesiology, Showa University Faculty of Medicine, Tokyo.
Yasumoto
K
K
Kuwasako
Y
Y
Shimada
C
C
Hosoyamada
A
A
D000328:Adult; D005652:Functional Residual Capacity; D006801:Humans; D011175:Positive-Pressure Respiration / Q000379:methods*