Inorganic fluoride concentration after long-term sedation with isoflurane

We report on five patients in whom long-term sedation with isoflurane for up to 7 days was used successfully. Serum inorganic fluoride concentrations were measured daily. The concentrations ranged from 12 mmol l-1 to 29 mmol l-1. These were well below the described renal toxic level of 50 mmol l-1. There was no deterioration in renal function attributable to the use of isoflurane.