Acute lung injury after peppermint oil injection

We describe a case of acute lung injury following IV injection of peppermint oil. An 18-yr-old woman injected the oil and developed fulminant pulmonary edema requiring ventilator support. Within 4 h after injection her arterial oxygen tension was 8.1 kPa (60 mm Hg) at an inspired oxygen fraction (FIO2) of 0.7 (P/F ratio: 85) despite a positive end expiratory pressure (PEEP) of 20 mbar, therefore meeting criteria for acute respiratory distress syndrome (ARDS). Mean pulmonary artery pressures and pulmonary artery wedge pressures were within normal limits throughout the case (<25 mm Hg and <10 mm Hg, respectively). Ventilation with high PEEP and diuresis resulted in a P/F ratio of 265 after 24 h. The patient was successfully weaned from the ventilator on the 9th day. This report is the first description of the sequelae of IV peppermint oil injection. The injection resulted in pulmonary edema and acute lung injury, presumably due to direct toxicity and a resultant increase in pulmonary vascular permeability.