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Effect of charcoal filter on the emergence from sevoflurane anesthesia in a semi-closed rebreathing circuit.

Chang DJ, Choi SH, Choi YS, Min KT - Yonsei Med. J. (2011)

Bottom Line: The elimination kinetics of sevoflurane from end-tidal concentration, Bispectral index and times of eye opening and extubation were obtained.The exponential time constant (τ) of alveolar sevoflurane concentration in the charcoal filter group was significantly shorter than that in the control group (1.7±0.5 vs. 2.5±1.1 min, p=0.008).The charcoal filter hastened rapid eye opening (11.1±3.8 vs. 14.8±3.0 min, p=0.007) and extubation (11.9±3.9 vs. 15.3±3.2 min, p=0.014), compared to the control group.

View Article: PubMed Central - PubMed

Affiliation: Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 250 Seongsan-ro, Seodaemun-gu, Seoul 120-752, Korea.

ABSTRACT

Purpose: A charcoal filter attached within the anesthetic circuit has been shown to efficiently adsorb halothane or isoflurane, thus hastening anesthetic recovery in low or minimal flow system. This study was intended to demonstrate whether the charcoal filter enhances the recovery time from sevoflurane anesthesia using a semi-closed circuit system.

Materials and methods: Thirty healthy patients scheduled for elective surgery under sevoflurane anesthesia were randomly assigned to the charcoal filter or control group. Upon completion of surgery, the end-tidal concentration of sevoflurane was maintained at 2.0 vol%. A charcoal filter was attached to the expiratory limb of the breathing circuit of charcoal filter group subjects. After sevoflurane was discontinued, ventilation was controlled with the same minute volume as the intra-operative period at a fresh gas flow rate of 5 L·min⁻¹ with 100% O₂. The elimination kinetics of sevoflurane from end-tidal concentration, Bispectral index and times of eye opening and extubation were obtained.

Results: The exponential time constant (τ) of alveolar sevoflurane concentration in the charcoal filter group was significantly shorter than that in the control group (1.7±0.5 vs. 2.5±1.1 min, p=0.008). The charcoal filter hastened rapid eye opening (11.1±3.8 vs. 14.8±3.0 min, p=0.007) and extubation (11.9±3.9 vs. 15.3±3.2 min, p=0.014), compared to the control group.

Conclusion: A charcoal filter enhances the recovery from sevoflurane anesthesia with a semi-closed rebreathing circuit.

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Related in: MedlinePlus

Effect of charcoal filter on end-tidal sevoflurane concentration (ET-sevo) for in vitro pretest. Artificial lung (5 L) was connected to a semi-closed breathing circuit and mechanically ventilated with 100% O2 at a fresh gas flow of 5 L·min-1 and a minute volume of 6 L·min-1. Sevoflurane was administered at a vaporizer dial setting of 1 vol% for three minutes. Dial setting was then raised to 2 vol% and 4 vol% every three minutes. Arrows indicate the beginning of each concentration of sevoflurane. ET-sevoflurane concentrations with the charcoal filter reached 80.0%, 76.4%, and 78.1% of those without the charcoal filter after 3 minute administration of 1, 2 and 4 vol% of sevoflurane, respectively.
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Figure 2: Effect of charcoal filter on end-tidal sevoflurane concentration (ET-sevo) for in vitro pretest. Artificial lung (5 L) was connected to a semi-closed breathing circuit and mechanically ventilated with 100% O2 at a fresh gas flow of 5 L·min-1 and a minute volume of 6 L·min-1. Sevoflurane was administered at a vaporizer dial setting of 1 vol% for three minutes. Dial setting was then raised to 2 vol% and 4 vol% every three minutes. Arrows indicate the beginning of each concentration of sevoflurane. ET-sevoflurane concentrations with the charcoal filter reached 80.0%, 76.4%, and 78.1% of those without the charcoal filter after 3 minute administration of 1, 2 and 4 vol% of sevoflurane, respectively.

Mentions: The in vitro pretest demonstrated that ET-sevo with the charcoal filter was lower than that without the charcoal filter. At every 3 minutes after turn-on sevoflurane with 1 vol%, 2 vol% and 4 vol% (arrows in Fig. 2 indicate the beginning of each concentration of sevoflurane), the measured sevoflurane concentration with the charcoal filter reached 80.0%, 76.4%, and 78.1% of the concentration, respectively, with the charcoal filter uninstalled (Fig. 2).


Effect of charcoal filter on the emergence from sevoflurane anesthesia in a semi-closed rebreathing circuit.

Chang DJ, Choi SH, Choi YS, Min KT - Yonsei Med. J. (2011)

Effect of charcoal filter on end-tidal sevoflurane concentration (ET-sevo) for in vitro pretest. Artificial lung (5 L) was connected to a semi-closed breathing circuit and mechanically ventilated with 100% O2 at a fresh gas flow of 5 L·min-1 and a minute volume of 6 L·min-1. Sevoflurane was administered at a vaporizer dial setting of 1 vol% for three minutes. Dial setting was then raised to 2 vol% and 4 vol% every three minutes. Arrows indicate the beginning of each concentration of sevoflurane. ET-sevoflurane concentrations with the charcoal filter reached 80.0%, 76.4%, and 78.1% of those without the charcoal filter after 3 minute administration of 1, 2 and 4 vol% of sevoflurane, respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3104448&req=5

Figure 2: Effect of charcoal filter on end-tidal sevoflurane concentration (ET-sevo) for in vitro pretest. Artificial lung (5 L) was connected to a semi-closed breathing circuit and mechanically ventilated with 100% O2 at a fresh gas flow of 5 L·min-1 and a minute volume of 6 L·min-1. Sevoflurane was administered at a vaporizer dial setting of 1 vol% for three minutes. Dial setting was then raised to 2 vol% and 4 vol% every three minutes. Arrows indicate the beginning of each concentration of sevoflurane. ET-sevoflurane concentrations with the charcoal filter reached 80.0%, 76.4%, and 78.1% of those without the charcoal filter after 3 minute administration of 1, 2 and 4 vol% of sevoflurane, respectively.
Mentions: The in vitro pretest demonstrated that ET-sevo with the charcoal filter was lower than that without the charcoal filter. At every 3 minutes after turn-on sevoflurane with 1 vol%, 2 vol% and 4 vol% (arrows in Fig. 2 indicate the beginning of each concentration of sevoflurane), the measured sevoflurane concentration with the charcoal filter reached 80.0%, 76.4%, and 78.1% of the concentration, respectively, with the charcoal filter uninstalled (Fig. 2).

Bottom Line: The elimination kinetics of sevoflurane from end-tidal concentration, Bispectral index and times of eye opening and extubation were obtained.The exponential time constant (τ) of alveolar sevoflurane concentration in the charcoal filter group was significantly shorter than that in the control group (1.7±0.5 vs. 2.5±1.1 min, p=0.008).The charcoal filter hastened rapid eye opening (11.1±3.8 vs. 14.8±3.0 min, p=0.007) and extubation (11.9±3.9 vs. 15.3±3.2 min, p=0.014), compared to the control group.

View Article: PubMed Central - PubMed

Affiliation: Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 250 Seongsan-ro, Seodaemun-gu, Seoul 120-752, Korea.

ABSTRACT

Purpose: A charcoal filter attached within the anesthetic circuit has been shown to efficiently adsorb halothane or isoflurane, thus hastening anesthetic recovery in low or minimal flow system. This study was intended to demonstrate whether the charcoal filter enhances the recovery time from sevoflurane anesthesia using a semi-closed circuit system.

Materials and methods: Thirty healthy patients scheduled for elective surgery under sevoflurane anesthesia were randomly assigned to the charcoal filter or control group. Upon completion of surgery, the end-tidal concentration of sevoflurane was maintained at 2.0 vol%. A charcoal filter was attached to the expiratory limb of the breathing circuit of charcoal filter group subjects. After sevoflurane was discontinued, ventilation was controlled with the same minute volume as the intra-operative period at a fresh gas flow rate of 5 L·min⁻¹ with 100% O₂. The elimination kinetics of sevoflurane from end-tidal concentration, Bispectral index and times of eye opening and extubation were obtained.

Results: The exponential time constant (τ) of alveolar sevoflurane concentration in the charcoal filter group was significantly shorter than that in the control group (1.7±0.5 vs. 2.5±1.1 min, p=0.008). The charcoal filter hastened rapid eye opening (11.1±3.8 vs. 14.8±3.0 min, p=0.007) and extubation (11.9±3.9 vs. 15.3±3.2 min, p=0.014), compared to the control group.

Conclusion: A charcoal filter enhances the recovery from sevoflurane anesthesia with a semi-closed rebreathing circuit.

Show MeSH
Related in: MedlinePlus