Serum fluoride in children anaesthetized with enflurane

The serum inorganic fluoride concentration (SF) was measured in 40 children aged 22 days to 11 yrs (five infants) undergoing enflurane anaesthesia lasting 20-200 min, at an inspiratory concentration of 0.8 or 1.0%. Regardless of age, SF peaked at 2-8 mumol l-1 after 20-40 min of enflurane exposure, and at 4-10 mumol 1-1 and 6-10 mumol l-1 after 41-90 min and 91-200 min of exposure, respectively. The highest individual value was 12.5 mumol l-1. Another 23 children, aged 1-16 yrs, received 0.8% enflurane for 60 min. The increase in SF was 3-9 mumol l-1, with no clear dependence on age. Altogether, the increase in SF was comparable to that detected in adults after anaesthesia of equal duration.