Patient-oxygen dissociation curves: surveying the spectrum of oxygen-delivery methods.

OBJECTIVE To describe the spectrum of oxygen-delivery methods. DESIGN Clinical audit. SETTING Medical wards of a tertiary referral teaching hospital in August 2004. PARTICIPANTS 98 medical patients receiving supplemental oxygen. RESULTS Of the 98 patients, 40 were not receiving oxygen by customary methods. In classifying the patterns of oxygen delivery, we describe the transcephalic, submental, and (inadvertent) rectal approaches, as well as lachrymal insufflation and the "Venturi cravat". We also describe novel oxygen-weaning methods, including the half-wean, reverse wean, and placebo wean. CONCLUSIONS Many patients receive oxygen by unconventional methods. We postulate that this is evidence of a renewed interest in the historical routes of oxygen delivery.