The investigation of the returned sevoflurane vaporizer concluded that the remaining liquid inside the vaporizer contained hydro fluoric acid, which was detected due to the low ph value measured on the residue inside the vaporizer.The inspection of parts after disassembly shows that some parts have been affected and corroded during the time inside the vaporizer.One observation was that no residues was found in the areas beyond the safety valve in the vaporizer which indicates no presence of hydro fluoric acid in this area and that the chemical reaction inside the vaporizer have started after the vaporizer was taken out of use.Since this vaporizer had been in use from 2017 until (b)(6) 2023, the reaction that may have created the hydric fluoride is not considered to be due to design and normal use of the vaporizer.The true cause of the issue has not been determined.
|