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Updated: Jun 22, 2026

Evaluation of Capnography Sampling Line Compatibility and Accuracy when Used with a Portable Capnography Monitor
Published on: September 29, 2020
Yet another cause for blocked sidestream capnogram--beware of the non-threaded cap mount in heat and moisture
Goneppanavar Umesh1, Kaur Jasvinder, Nanda Shetty
1Department of Anaesthesiology, Kasturba Medical College, Karnataka, India. drumeshg@yahoo.co.in
Abstract:
Heat and moisture exchangers (HME) are commonly used during general anaesthesia and intensive care of patients on mechanical ventilators. Some of the HME manufacturers provide HMEs with a Luer lock fitting for connecting side stream CO(2) monitoring line, Luer lock cap, and a non-threaded cap mount. However, HMEs from different manufacturers and HMEs meant for use in children and for adults from the same manufacturer vary in the presence/absence of non-threaded cap mount. This can create confusion to the clinicians and can result in inadvertent connection of the CO(2) monitoring line to the non-threaded cap mount resulting in blocked CO(2) monitoring line and leak in the circuit. We caution all the anaesthesiologists and intensivists regarding this possibility while using HMEs from different manufacturers.
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