Pulmonary edema following intrauterine methylene blue injection.

Methylene blue is a commonly used dye in diagnostic procedures such as fistula detection, delineation of body tissues during surgery and for checking the patency of fallopian tubes. Many such dyes interfere with accurate measurement of oxygen saturation by a pulse oximeter. We report here a case in which methylene blue hot only interfered with pulse oximetery but also caused pulmonary edema in an ASA grade 1 patient.