The Invention of Anesthetic Gas Return Connector for Anesthetic Machine

Main Article Content

Jittima Jiarpinitnun
Vorasruang Thongsukh
Kasem Trongtokit
Junjeera Kochasan


Background and Purposes: Sidestream capnograghy is a potentially lifeaving tool for monitoring the ventilation in patients receiving general anesthesia. The sample gas that withdraw continuously throughout respiratory cycle and sampled in an analyzer contained anesthetized gases. Without proper control, these released gases after analysis may stay diffused in the operating room, affecting the personnel's health condition. The purpose of this article was to invent the connector for using with anesthetic machine particularly thoes that having no part of sampling gas return port, in order to reduce the risk of pollution analyzed gases.

Method: To create a connector for delivering analyzed gases from the sidestream capnography back into the breathing circuit system of the anesthetic machine that does not have a sampling gas return port or for ventilating them for reuse.

Results: The anesthetic gas return connector is an invention used with anedthetic machine that does not have a sample gas return port for the improvement of anesthetic service quality. This invention leads to the significant decrease in the budget of operation.

Conclusion: The anesthetic gas return connector is a self-sufficient, inexpensive, practical and highly efficient invention that could be sterilized and reused. The anesthesiologist could safely use the sidestream capnography to monitor the patient in the operating room.

Article Details

How to Cite
Jiarpinitnun, J., Thongsukh, V., Trongtokit, K., & Kochasan, J. (2014). The Invention of Anesthetic Gas Return Connector for Anesthetic Machine. Ramathibodi Medical Journal, 37(1), 2–8. Retrieved from
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