title: Paracetamol metabolism after general anaesthesia.
abstract: Paracetamol metabolism was compared between nine patients after general anaesthesia and nine healthy volunteers. Each subject received 1.5 g of paracetamol orally, and paracetamol concentrations in venous blood were measured by HPLC at intervals over 12 h. Urine samples collected over 24 h were analysed by HPLC for cysteine, mercapturic acid, sulphate and glucuronide metabolites. There were no significant differences in the area under the concentration-time curve for paracetamol, or plasma half-life. Statistically significant differences were observed in the median percentages of unchanged paracetamol (volunteers 2.9%, patients 2.0%) and mercapturic acid (volunteers 4.5%, patients 6.5%) excreted in 24 h. The percentage of sulphate excreted was significantly lower in the 8-24-h period, although there was no difference over the total 24 h.
authors.affiliation: University Department of Anaesthesia, Medical School, Sheffield, United Kingdom.
authors.forename: R P
authors.initials: RP
authors.lastname: Lewis
authors.forename: J A
authors.initials: JA
authors.lastname: Dunphy
authors.forename: C S
authors.initials: CS
authors.lastname: Reilly
mesh_terms: D000082:Acetaminophen / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics / Q000652:urine; D000111:Acetylcysteine / Q000097:blood / Q000652:urine; D000328:Adult; D000768:Anesthesia, General; D000769:Anesthesia, Inhalation; D000771:Anesthesia, Intravenous; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D013431:Sulfates / Q000097:blood / Q000652:urine; D013997:Time Factors
chemical_list: D013431:Sulfates; D000082:Acetaminophen; D000111:Acetylcysteine