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Published on: October 25, 2015
A syringe adapter to facilitate aspiration at amniocentesis
J N Robinson1, H H Loeffler, E R Norwitz
1Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA. jrobinson@bics.bwh.harvard.edu
Background:
Syringes were developed for injection, not aspiration. We describe an adapter that attaches to a standard syringe and aspirates by advancement rather than withdrawal.
Technique:
The adapter consists of a syringe barrel extension and an attachable finger grip. The adapter attached to a standard syringe allows aspiration by advancement rather than withdrawal, with the same hand motion used as with injection.
Experience:
In a comparison of timed in vitro fluid aspiration by 10 practitioners, mean times for aspiration of 15 mL were 32.4 seconds (range 24-45) with standard technique and 25.3 seconds (range 24-30) with the adapted syringe (P < .003, paired t test). Thirteen of 14 physicians who used the adapted syringe in vivo reported that much less effort was required, and one physician reported that a little less effort was required. Overall, eight practitioners reported that the adapted syringe made amniocentesis much easier and six found no difference between the two devices.
Conclusion:
This adapter converts a standard syringe to one permitting aspiration by advancement rather than withdrawal. Practitioner feedback was positive with regard to ease of use, degree of effort, and overall satisfaction.

