Allergic contact dermatitis from oxygen cannulas

A patient experienced allergic contact dermatitis on two occasions two months apart as a result of wearing the same brand of polyvinyl chloride oxygen cannula. In one instance the cannula was removed and not replaced, as continuing oxygen was unnecessary; on the other occasion the original cannula was replaced by a cannula of another brand. In both cases the dermatitis disappeared after removal of the original cannula. The reaction was probably to a resin remaining in the polyvinyl chloride after the curing process in the manufacture of the plastic from which the cannula was made. Allergic reactions to plastics have been documented in other medical products but have not previously been reported in respiratory therapy plastic appliances. Because of variability in residual resins in different brands and batches of plastics, and because of varying individual sensitivity, therapists and others should be alert to the possibility of allergic contact dermatitis from respiratory therapy devices.