This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Mazze, R. I. Search for Related Content PubMed PubMed Citation Articles by Mazze, R. I.

---

LETTERS TO THE EDITOR

Novel CO₂ Absorbents and Low-Flow Sevoflurane

Department of Anesthesia Stanford University Stanford, CA 94305

To the Editor:

As a reviewer for the Journal of the article by Yamakage et al. (1), I was surprised to see that when it was published the title originally proposed by the authors, "Comparative Study of the Degradation of Sevoflurane Compound A with Novel CO₂ Absorbents in Low-Flow Anesthesia," had been changed. The title under which it appeared was "Carbon Dioxide Absorbents Containing Potassium Hydroxide Produce Much Larger Concentrations of Compound A from Sevoflurane in Clinical Practice."

The article by Yamakage et al. (1) is about two novel CO₂ absorbents. Its main findings were the absence of an increase in Compound A levels when Amsorb^TM (Armstrong, Coleraine, Northern Ireland) was used with sevoflurane at fresh gas flow rates of 1 or 2 L/min for 4 h and markedly reduced levels of Compound A when Medisorb^TM (Datex-Ohmeda, Louisville, CO) was used. These agents contain either no KOH (Amsorb^TM) or only trace levels (Medisorb^TM). As expected, elevated levels of Compound A were seen when the control agents (Wakoline^TM [Wako, Tokyo, Japan] and Drägersorb^TM 800 [Dräger, Lübeck, Germany]) were used, both of which contain significant amounts of KOH. Unfortunately, the new title that focused on the control agents distorted the major finding of the research. The result was an investigation that reported markedly lower levels of Compound A with the novel absorbents and, hence, enhanced safety (if Compound A levels in surgical patients is a safety concern), was published with a title that grouped the phrases, CO₂ absorbents, much larger concentrations of Compound A, and sevoflurane in clinical practice—implying lack of safety.

The purpose of writing this letter is to emphasize the importance of the authors’ findings. There was no increase or only a trivial increase in Compound A levels when the novel CO₂ absorbents were used with sevoflurane at a fresh gas flow rate of 1 L/min for 4 h. Examination of the authors’ data suggests that their results can be extrapolated to lower fresh gas flow rates and to longer anesthetic exposures. Clinical use of the novel CO₂ absorbents would make moot the now tedious argument that has been going on for years about the renal toxicity of Compound A and, hence, sevoflurane (2).

References

1. Yamakage M, Yamada S, Chen X, et al. Carbon dioxide absorbents containing potassium hydroxide produce much larger concentrations of Compound A from sevoflurane in clinical practice. Anesth Analg 2000; 91: 220–4.[Abstract/Free Full Text]
2. Bedford RF, Ives HE. The renal safety of sevoflurane. Anesth Analg 1999; 99: 505–8.

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Mazze, R. I. Search for Related Content PubMed PubMed Citation Articles by Mazze, R. I.