Articles: closed-circuit-anesthesia.
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Comparative Study
Effects of temperature gradient reduction in three different carbon dioxide absorbents.
Temperature gradients in CO2 absorbents may locally increase the water content by condensation. We hypothesized that temperature gradient reduction (TGR) would prevent increased water content, thus preserving the reactivity of the CO2 absorbent and thereby increasing its time to exhaustion (longevity). The purpose of this study was to compare the effects of TGR on the longevity of CO2 absorbent with three different types of CO2 absorbents. ⋯ TGR is a useful method to prevent local increase in water content and improve the longevity of CO2 absorbent. The effectiveness of TGR on longevity and water content changes varied in the different types of CO2 absorbent.
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Baby EAR circuit is a new modified enclosed afferent reservoir anesthetic breathing system for pediatric patients. By following His Majesty the King of Thailand's self-sufficiency philosophy, the circuit is simple and made of low-cost and easy-to-find materials found in the operating room. This present study was to investigate clinical use of the circuit and to find the optimal fresh gas flow in clinical setting. ⋯ Baby EAR circuit can be made economically and used safely for general anesthesia with control ventilation in pediatric patients weighing 5 to 20 kg at optimal fresh gas flow of 3 LPM.
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Anesthesia and analgesia · Apr 2009
Comparative StudyTime to a 90% change in gas concentration: a comparison of three semi-closed anesthesia breathing systems.
The speed with which gas concentration can be changed in the anesthesia breathing system affects the rate of denitrogenation, anesthesia induction, and emergence. Breathing system design also affects the speed at which gas concentration can be changed during maintenance. In this study, we sought to determine the speed of changes in gas concentration in modern semi-closed breathing systems. We hypothesized that equilibrium would be reached most quickly in breathing systems with smaller volume, and at high fresh gas flows. ⋯ We concluded that, other than fresh gas flow rate, breathing system volume has the biggest effect on time to equilibrium when the composition of the fresh gas inflow is changed. The position of components (e.g., valves, carbon dioxide absorber, fresh gas inlet, ventilator bellows or piston) within the breathing system has a less pronounced effect.