Korean J Anesthesiol.  2015 Aug;68(4):392-396. 10.4097/kjae.2015.68.4.392.

Time course of end-tidal desflurane concentration during delivery and elimination according to the type and location of filters in a semi-closed circuit system

• Park SW
• Chung JY
• Moon EJ
• Kang YJ
• Kang JM

• KMID: 2152883
• DOI: http://doi.org/10.4097/kjae.2015.68.4.392

Abstract

BACKGROUND
The aim of this study was to determine whether the end-tidal concentration of desflurane would be affected by a breathing circuit system filter attached at two different positions in anesthetic breathing circuit systems.
METHODS
An artificial lung was ventilated under five different conditions. The first group was without any filter or desflurane (n = 5, sham), the second was with desflurane but without any filter (n = 10, control), the third group had a bacterial filter on the expiratory limb (n = 10), and the fourth and fifth groups had a viral/bacterial filter added on the expiratory limb (n = 10) or at the Y-piece of the breathing circuit (n = 10), respectively. In all groups except the sham, administration of 10% desflurane was performed for 5 minutes and then stopped for 5 minutes.
RESULTS
The mean (SD) end-tidal concentration of desflurane for the groups described above peaked at 0 (0), 9.8 (0.1), 9.8 (0.1), 8.5 (0.1), and 6.7% (0.1) (P < 0.001), respectively. There was no difference in the desflurane concentrations and the expired tidal volume over time between the control and bacterial group, but there was a significant difference between the control and the fourth and fifth groups (P < 0.001).
CONCLUSIONS
Filters can affect the expiratory desflurane concentration during anesthesia.

Keyword

Concentration; Desflurane; Filter; Tidal volume

MeSH Terms

Anesthesia
Extremities
Lung
Respiration
Tidal Volume