title: Effect of magnesium sulphate on urinary catecholamine excretion in severe tetanus.
abstract: Severe tetanus is characterised by muscle spasms and autonomic dysfunction. We recently reported the results of a randomised placebo controlled trial of magnesium sulphate infusions for the treatment of severe tetanus which showed magnesium was associated with improved muscle spasm and cardiovascular control. We hypothesised that magnesium controlled autonomic dysfunction by reducing catecholamine release and thus urinary excretion. Urinary adrenaline and noradrenaline concentrations were measured during the first 24 h of therapy in 180 adults with severe tetanus randomised to treatment with magnesium (n = 92) or placebo (n = 88). Magnesium therapy was associated with lower urinary adrenaline excretion and higher urinary noradrenaline excretion. High urinary adrenaline concentrations were associated with documented autonomic dysfunction. Patients given magnesium had significantly less autonomic dysfunction, required less cardiovascular stabilising drugs, and had lower urinary concentrations of adrenaline. These findings suggest adrenaline is important in the pathophysiology of severe tetanus and magnesium controls autonomic dysfunction by reducing adrenaline release.
authors.affiliation: Oxford University Clinical Research Unit, Hospital for Tropical Diseases, 190 Ben Ham Tu, District 5 Ho Chi Minh City, Vietnam. louise.thwaites@btinternet.com
authors.forename: C L
authors.initials: CL
authors.lastname: Thwaites
authors.forename: L M
authors.initials: LM
authors.lastname: Yen
authors.forename: S M
authors.initials: SM
authors.lastname: Cordon
authors.forename: G E
authors.initials: GE
authors.lastname: Thwaites
authors.forename: H T
authors.initials: HT
authors.lastname: Loan
authors.forename: T T D
authors.initials: TT
authors.lastname: Thuy
authors.forename: N J
authors.initials: NJ
authors.lastname: White
authors.forename: N
authors.initials: N
authors.lastname: Soni
authors.forename: I A
authors.initials: IA
authors.lastname: Macdonald
authors.forename: J J
authors.initials: JJ
authors.lastname: Farrar
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000927:Anticonvulsants / Q000097:blood / Q000494:pharmacology* / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D003975:Diazepam / Q000494:pharmacology; D004311:Double-Blind Method; D004837:Epinephrine / Q000652:urine*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008278:Magnesium Sulfate / Q000097:blood / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000652:urine*; D017300:Pipecuronium / Q000494:pharmacology; D013742:Tetanus / Q000097:blood / Q000188:drug therapy / Q000652:urine*
chemical_list: D000927:Anticonvulsants; D017300:Pipecuronium; D008278:Magnesium Sulfate; D003975:Diazepam; D009638:Norepinephrine; D004837:Epinephrine