Development and validation of a direct headspace GC-FID method for the determination of sevoflurane, desflurane and other volatile compounds of forensic interest in biological fluids: application on clinical and post-mortem samples.

A simple and reliable headspace GC-flame ionization detection (HS-GC-FID) method has been developed and validated for the simultaneous determination of seven volatile compounds of forensic interest: sevoflurane, desflurane, ethanol, methanol, 1-propanol, acetone and acetaldehyde. All seven compounds including acetonitrile (internal standard) eluted within 10 min and were well resolved with no endogenous interference. Good linearity was observed in the range of 1-12 mg/dL for both anesthetics and 2.5-40 mg/dL for the other five analytes. The method showed good precision, sensitivity and repeatability. Most of the analytes remained stable during the storage of samples at 4°C. Desflurane and acetone degraded (>10%), when the samples remained on the autosampler for more than 2 and 3 h, respectively. The method was finally applied on clinical and post-mortem blood and urine samples. The clinical samples were collected both from patients who underwent surgery, as well as from the occupationally exposed medical and nursing staff of the university hospital, working in the operating rooms. The hospital staff samples were found negative for all compounds, while the patients' samples were found positive for the anesthetic administered to the patient. The post-mortem blood samples were found positive for ethanol and acetaldehyde.