Vecuronium pharmacokinetics in patients with major burns.
BACKGROUND
Burn patients develop resistance to non-depolarizing neuromuscular blocking agents (NDNMBAs) and require a significantly large dose to produce a desired clinical response. Pathophysiological changes related to burn injury may alter pharmacokinetics (PK) and pharmacodynamics of NDNMBAs. The purpose of this study was to compare vecuronium PK in burns vs non-burns.


METHODS
Twenty adults, aged 23-58 yr, with 27-81% total body surface area (TBSA) burn, were studied at 4-57 post-burn days and compared with age- and sex-matched, non-burn controls. Vecuronium 0.12 mg kg(-1) was given i.v. as a single bolus within 10 s. Blood samples (n=20) were collected over 12 h at predetermined time points. NONMEM was used to describe plasma drug concentration-time profiles for burns and non-burns.


RESULTS
A three-compartment model best described vecuronium concentration-time profiles. Burn patients showed enhanced distributional clearance at the terminal phase (0.12 vs 0.095 litre min(-1), P<0.0001), which yielded shorter elimination half-life for vecuronium (5.5 vs 6.6 h, P<0.001). BURN was the single most significant covariate that explained the altered vecuronium disposition in burns.


CONCLUSIONS
The altered drug distribution between tissues may partially explain the known resistance to vecuronium in patients with major burns.
Department of Pharmaceutical Sciences, College of Pharmacy, CPB 331, University of Oklahoma Health Sciences Center, 1110 N. Stonewall Ave., Oklahoma City, OK 73117, USA.
K R
KR
Vega-Villa
K
K
Kaneda
S
S
Yamashita
S
S
Woo
T H
TH
Han
D000328:Adult; D002056:Burns / Q000097:blood / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009466:Neuromuscular Blocking Agents / Q000097:blood / Q000493:pharmacokinetics*; D014673:Vecuronium Bromide / Q000097:blood / Q000493:pharmacokinetics*; D055815:Young Adult
D009466:Neuromuscular Blocking Agents; D014673:Vecuronium Bromide
burns; neuromuscular block; population pharmacokinetics; vecuronium