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Objectives: To evaluate the cryo-analgesic effect of ethyl chloride spray on reducing pain during second-trimester amniocentesis.
Materials and Methods: A non-blinded randomized controlled trial was performed to compare the post-procedural pain scores during second-trimester amniocentesis between pregnant women who received and did not receive ethyl chloride spray immediately before amniocentesis needle penetration. Outcome was mean of post-procedural pain score measured by using visual analogue scale (VAS).
Results: The study was performed between May and November 2016. One hundred and forty-eight participants were randomly divided into two groups received cryo-analgesia using ethyl chloride spray and did not receive. There were no differences between demographic data and pre-procedural pain scores (anticipated pain) (p = 0.6). Mean post-procedural pain score in the cryo-analgesia group was significantly lower than the control group (p = 0.01). Six participants in cryo-analgesia group had frostbite skin rash (8%) which was self-limiting condition and persists for about one month with no scar. Most participants (98%) willingly accepted to undergo the procedure again if indicated.
Conclusion: Ethyl chloride spray may be an alternative method for amniocentesis procedural pain management. Women should be informed about the potential risk of complications.
Keywords: Amniocentesis, pain, ethyl chloride spray, visual analogue scale.
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