An assembly (10) for removing carbon dioxide from patient expired gas during anesthesia is described. The assembly (10) comprises a chamber (12) configured to contain an adsorbent (14) for treating the patient expired gas during a capture mode of operation and return treated patient expired gas to an anesthesia machine integral regeneration equipment (28, 30, 44) configured to regenerate the adsorbent (14) during a release mode of operation and a control device for switching from the capture mode of operation to the release mode of operation.
