We thank Dr. Baum for his letter, bringing the 1995 publication of Keifer and Stirt1to our attention. This experience lends a new interpretation to the comment of Ambrose Bierce, the 19th-century American writer, that “there is nothing new under the sun, but there are lots of old things we don’t know.”*Neither of us was aware of a previous description of the technique we labeled “mouth-to-circuit,”2and of the dozens of people with whom we have shared it, all have received our description as new and refreshing. Hence, we assume that none of them knew of the earlier report1either.

Perhaps this oversight resulted from our approach to the problem. The senior of us (W.L.L.) has long been interested in introducing readily incorporated solutions to perplexing problems of airway management and oxygenation. Examples include reports on improving mask fit in edentulous patients3and a technique for providing prolonged oxygen administration in aircraft.4Our report in the February issue of Anesthesiology2was directed at improving oxygen delivery and a sense of psychological well-being in claustrophobic patients. Our screening of the literature, using PubMed, followed this view. Searches combining the term claustrophobia  with preoxygenation , airway , oxygen , anesthesia , anesthesiology , and mask  all failed to identify the 124-word Keifer and Stirt publication. This is likely because the Keifer and Stirt report refers to patients experiencing “fear” or a “sense of ‘smothering’” but never mentions the term claustrophobia .

Our report offers some features not provided in the earlier Kiefer and Stirt report, including (1) a quantitative expression of our considerable experience and success with the technique, (2) the physiologic and psychological factors contributing to the success of the method, (3) alternative techniques that can be considered, (4) the role of nasal occlusion, and (5) circuit gas analysis when using the mouth-to-circuit technique versus  preoxygenation using a conventional mask approach. We acknowledge, however, that the Kiefer and Stirt report effectively and concisely covered all of the fundamentals of the technique, and our additions are merely gilding to the core story. Had we known of their publication early on, we would not have considered submitting our report for publication or performing the institutional review board—approved research included in our report (i.e. , the portion of the report identified by the Editor-in-Chief of Anesthesiology as critical for approval). Had we discovered the Kiefer and Stirt report later, we certainly would have given them their due credit for describing this useful technique.

If there is a lesson to be learned from this experience, it is that—in the current era of rapidly growing medical literature and dependence on computer-facilitated methods to archive information—literature searches are dependent on identifier- and metadata-rich titles and (when appropriate) abstracts to facilitate retrieval.5Had Kiefer and Stirt been sufficiently prescient in 1995 to foresee this revolution in information management, they probably would have loaded the title of their report with more information-rich phraseology than the as-published single word, “Preoxygenation.”1 

†Mayo Clinic College of Medicine, Rochester, Minnesota. erickson.kirstin@mayo.edu

Keifer RB, Stirt JA: Preoxygenation (letter). Anesthesiology 1995; 83:429
Erickson KM, Lanier WL: Preoxygenation in claustrophobic patients (letter). Anesthesiology 2006; 104:387–8
Lanier WL: Improving anesthesia mask fit in edentulous patients. Anesth Analg 1987; 66:1053
Lanier WL, Weeks DB: Portable semiclosed circuit for prolonged oxygen administration in aircraft. Anesthesiology 1985; 63:116–8
Brand A, Daly F, Meyers B: Metadata Demystified. Hanover, Pennsylvania, Sheridan Press, 2003, p 15
Hanover, Pennsylvania
Sheridan Press