Effect of Ethyl Chloride Spray for Pain Reduction during Amniocentesis: A non – blinded randomized controlled trial

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Kritakarn Telapol
Sommart Bumrungphuet
Nathpong Israngura Na Ayudhya


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.

Article Details

How to Cite
Telapol, K.; Bumrungphuet, S.; Israngura Na Ayudhya, N. Effect of Ethyl Chloride Spray for Pain Reduction During Amniocentesis: A Non – Blinded Randomized Controlled Trial. Thai J Obstet Gynaecol 2018, 26, 75-82.
Original Article
Author Biographies

Kritakarn Telapol, Department of Obstetrics and Gynaecology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand

Department of Obstetrics and Gynaecology, Faculty of Medicine

Sommart Bumrungphuet, Department of Obstetrics and Gynaecology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand

Department of Obstetrics and Gynaecology, Faculty of Medicine


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