IN VIVO RECOVERY OF RISTOCETIN CO-FACTOR IN PATIENTS WITH VON WILLEBRAND DISEASE UNDERGOING PROCEDURES REQUIRING TREATMENT WITH HAEMATE P
Abstract number: P-W-176
Watt1 S.G., Nash1 M., Walsh1 M.L., Birtwistle1 L., Bolton-Maggs1 P., Hay1 C.R.M.
1Haematology, Manchester Royal Infirmary, Manchester, United Kingdom
How-to-cite Watt SG, Nash M, Walsh ML, Birtwistle L, Bolton-Maggs P, Hay CRM. IN VIVO RECOVERY OF RISTOCETIN CO-FACTOR IN PATIENTS WITH VON WILLEBRAND DISEASE UNDERGOING PROCEDURES REQUIRING TREATMENT WITH HAEMATE P. J Thromb Haemost 2007; 5 Supplement 2: P-W-176
Introduction: It is important to ensure that the dose of clotting factor concentrate patients receive is within the therapeutic range to minimise risk of bleeding or thrombosis in patients undergoing invasive procedures.
This study looked at the data in patients with von Willebrand disease (VWD) who underwent procedures requiring Haemate P treatment between 2002-2006.
Methods: We obtained a minimum dataset of weight, dose of factor concentrate, age, sex, pre and post first dose of concentrate levels for factor VIII and ristocetin cofactor (VWF:RCo) and type of VWD on 30 patients for 33 episodes.
Results: There were 23 episodes with females and 10 with males. 21 had type 1 VWD, 10 type 2 and 2 type 3. Median age was 45 (range 21-84). Mean dose of Haemate P was 37.6 units of factor VIII per kilogram (range 22.5-54.5) equivalent to 90.2 VWF:RCo units. Data sources were casenotes and laboratory results.
Data showed a wide range of results with a mean recovery of 1.50IU/dl per IU/kg of VWF:RCO administered (standard deviation= 0.55, range 0.56 to 2.43). There was no significant difference in recovery between the mean of males (1.48) and females (1.50). There was an inverse correlation (-0.55) between increasing doses per kilogram and recovery. There was some correlation (0.36) between increasing weight and recovery. There is no correlation between recovery and age or sex of the patient.
Conclusions: Our study showed that recovery cannot be predicted for individuals. There was a fall in recovery with larger doses of concentrate per kilogram and there appears to be greater recovery in larger patients. The mean recovery of 1.50IU/dl per IU/kg of VWF:RCO administered is the same as stated in the Haemate P summary of product characteristics.
The study shows the importance of dosing based on VWF:RCo levels in pre and post operative patients.
To cite this abstract use the following format:
Journal of Thrombosis and Haemostasis 2007; Volume 5, Supplement 2: abstract number
||XXIst ISTH Congress
| Back to top