TY - JOUR
T1 - The effect of fresh gas flow rate and type of anesthesia machine on time to reach target sevoflurane concentration
AU - Shin, Hye Won
AU - Yu, Hae Na
AU - Bae, Go Eun
AU - Huh, Hyub
AU - Park, Ji Yong
AU - Kim, Ji Young
N1 - Publisher Copyright:
© 2017 The Author(s).
PY - 2017/1/19
Y1 - 2017/1/19
N2 - Background: Anesthesia machines have been developed by the application of new technology for rapid and easier control of anesthetic concentration. In this study, we used a test lung to investigate whether the time taken to reach the target sevoflurane concentration varies with the rate of fresh gas flow (FGF) and type of anesthesia machine (AM). Methods: We measured the times taken to reach the target sevoflurane concentration (2 minimum alveolar concentration = 4%) at variable rates of FGF (0.5, 1, or 3 L/min) and different types of AM (Primus®, Perseus®, and Zeus® [Zeus®-F; Zeus® fresh gas mode, Zeus®-A; Zeus® auto-mode]). Concomitant ventilation was supplied using 100% O2. The AMs were connected to a test lung. A sevoflurane vaporizer setting of 6% was used in Primus®, Perseus®, and Zeus®-F; a target end-tidal setting of 4% was used in Zeus®-A (from a vaporizer setting of 0%). The time taken to reach the target concentration was measured in every group. Results: When the same AM was used (Primus®, Perseus®, or Zeus®-F), the times to target concentration shortened as the FGF rate increased (P < 0.05). Conversely, when the same FGF rate was used, but with different AMs, the time to target concentration was shortest in Perseus®, followed by Primus®, and finally by Zeus®-F (P < 0.05). With regards to both modes of Zeus®, at FGF rates of 0.5 and 1 L/min, the time to target concentration was shorter in Zeus®-A than in Zeus®-F; however, the time was longer in Zeus®-A than in Zeus®-F at FGF rate of 3 L/min (P < 0.05). Conclusion: Shorter times taken to reach the target concentration were associated with high FGF rates, smaller internal volume of the AM, proximity of the fresh gas inlets to patients, absence of a decoupling system, and use of blower-driven ventilators in AM.
AB - Background: Anesthesia machines have been developed by the application of new technology for rapid and easier control of anesthetic concentration. In this study, we used a test lung to investigate whether the time taken to reach the target sevoflurane concentration varies with the rate of fresh gas flow (FGF) and type of anesthesia machine (AM). Methods: We measured the times taken to reach the target sevoflurane concentration (2 minimum alveolar concentration = 4%) at variable rates of FGF (0.5, 1, or 3 L/min) and different types of AM (Primus®, Perseus®, and Zeus® [Zeus®-F; Zeus® fresh gas mode, Zeus®-A; Zeus® auto-mode]). Concomitant ventilation was supplied using 100% O2. The AMs were connected to a test lung. A sevoflurane vaporizer setting of 6% was used in Primus®, Perseus®, and Zeus®-F; a target end-tidal setting of 4% was used in Zeus®-A (from a vaporizer setting of 0%). The time taken to reach the target concentration was measured in every group. Results: When the same AM was used (Primus®, Perseus®, or Zeus®-F), the times to target concentration shortened as the FGF rate increased (P < 0.05). Conversely, when the same FGF rate was used, but with different AMs, the time to target concentration was shortest in Perseus®, followed by Primus®, and finally by Zeus®-F (P < 0.05). With regards to both modes of Zeus®, at FGF rates of 0.5 and 1 L/min, the time to target concentration was shorter in Zeus®-A than in Zeus®-F; however, the time was longer in Zeus®-A than in Zeus®-F at FGF rate of 3 L/min (P < 0.05). Conclusion: Shorter times taken to reach the target concentration were associated with high FGF rates, smaller internal volume of the AM, proximity of the fresh gas inlets to patients, absence of a decoupling system, and use of blower-driven ventilators in AM.
KW - Equipment design
KW - Inhalation anesthetics
KW - Ventilation
UR - http://www.scopus.com/inward/record.url?scp=85009935518&partnerID=8YFLogxK
U2 - 10.1186/s12871-016-0294-y
DO - 10.1186/s12871-016-0294-y
M3 - Article
C2 - 28103806
AN - SCOPUS:85009935518
SN - 1471-2253
VL - 17
JO - BMC Anesthesiology
JF - BMC Anesthesiology
IS - 1
M1 - 10
ER -