Sulfur hexafluoride and perfluoropropane do not escape from a plastic syringe closed with a stopcock.
OBJECTIVE
To evaluate during various intervals of time the escape of long-acting gases contained in a plastic syringe closed with a stopcock or a plastic cap.


METHODS
A 60-ml plastic syringe was filled or partially filled with a long-acting gas, either sulfur hexafluoride or perfluoropropane. The tip of the syringe was closed with either a stopcock or the syringe's plastic cap. After various intervals of time, the concentration of the long-acting gas in the syringe was measured by gas chromatography.


RESULTS
The concentration of both long-acting gases was higher than 98% at 24 hours after filling when the syringe was closed with a stopcock; however, it was less than 41% when the syringe was filled and capped tightly with its plastic cap.


CONCLUSIONS
The proportion of long-acting gases escaping in 24 hours from a filled syringe capped with a stopcock is clinically insignificant.
Ohji
M
M
Department of Ophthalmology, Osaka University Medical School, Suita, Japan.
Adachi
F
F
Tano
Y
Y
D002849:Chromatography, Gas; D004058:Diffusion; D005466:Fluorocarbons / Q000032:analysis*; D013459:Sulfur Hexafluoride / Q000032:analysis*; D013594:Syringes; D013997:Time Factors
D005466:Fluorocarbons; C042852:perflutren; D013459:Sulfur Hexafluoride