Pharmacokinetic-guided dosing of factor VIII concentrate in a morbidly obese severe haemophilia A patient undergoing orthopaedic surgery.

A 58-year-old morbidly obese male (body mass index: 38 kg/m ² ) with severe haemophilia A underwent total knee replacement surgery. Perioperatively, factor VIII (FVIII) levels were measured daily and maximum a posteriori (MAP) Bayesian estimation was used to calculate the individual pharmacokinetic (PK) parameters and doses required to obtain prescribed FVIII target levels. In the MAP Bayesian procedure, a population PK model was used in which PK parameters were normalised using body weight. In this specific case, ideal body weight was used to scale the PK parameters instead of actual body weight. Except for the preoperative FVIII level, adequate FVIII levels were achieved during the 10-day perioperative period. During follow-up visits, the knee prosthesis was reported to function adequately.
Competing Interests: Competing interests: BLvG has received unrestricted educational grants from Baxter and CSL Behring. MHC has received unrestricted research grants for investigator-initiated studies and educational as well as travel grants from Pfizer, Shire, Bayer, Novo Nordisk, CSL Behring, Novartis and Roche. RAAM has received travel grants from Shire and Bayer. The remaining authors declare no competing financial interests.
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