Sudden deaths due to accidental intravenous injection of perfluorocarbon during MRI cranial examinations

Abstract

Unexpected deaths of three patients happened at a magnetic resonance imaging (MRI) clinic during cranial examinations with gadolinium-based contrast media. A toxicological screening using liquid chromatography–tandem mass spectrometry (LC–MS–MS) and gas chromatography–mass spectrometry (GC–MS) for blood and urine samples collected during autopsy of the cases resulted negative. During the police investigation, it was learned that a special brand of perfluorocarbon (FC-770) had been in use at the radiological clinic for prostatic, genitals, and external soft tissue examinations, and could supposedly be available in the room where the cranial MRI examinations were performed. Histologically the lungs of the three victims showed alveolar edema associated with pulmonary venous air embolism. Using a target LC–MS–MS method, gadolinium-based contrast agents Gd-DTPA and Gd-DOTA were detected in blood samples and results showed lower levels of Gd-DTPA and Gd-DOTA when compared with literature data for that kind of MRI examinations. Free gadolinium (Gd3+) was also determined by inductively coupled plasma–mass spectrometry in blood samples showing also low levels. Perfluorocarbon FC-770 was determined in blood by headspace–GC–MS. Results showed the presence of 19.3, 20.9, and 20.0 μg/ml of FC-770 in blood of the three victims, estimating an injected dose of at least 230, 180, and 180 mg/kg, respectively. The smallest fatal dose established in an early experimental study was estimated to be 6.8 mg/kg. The investigations concluded that mistakenly intravenous injection of FC-770 led to the deaths of the three victims by a mechanism of pulmonary venous gas embolism secondary to the presence of non absorbable and high vapor pressure FC-770 in the pulmonary capillaries.