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Quantitative assessment of postoperative blood collection in brain tumor surgery under valproate medication
T Psaras1, B E Will, W Schoeber
1Department of Neurosurgery, University of Tuebingen, Tuebingen, Germany. tsambika.psaras@med.uni-tuebingen.de
Background:
The aim of the study was to evaluate whether valproate (VPA) increases the risk of bleeding complications in patients undergoing brain tumor surgery.
Methods:
A retrospective chart review of 85 patients operated on between January and December 2005 was performed. 19 patients received VPA, 22 patients were given other anti-epileptic drugs (AEDs), 44 patients received no AEDs. Data analyzed included intraoperative blood loss, transfusion, important comorbidity factors and concomitant diseases. Preoperative and postoperative laboratory data included hemoglobin, hematocrit, fibrinogen, platelet count, INR, prothrombin time, partial thromboplastin time and RBC count. The tumor volume was evaluated by preoperative MRI and CT scans of the brain. All 85 patients underwent a native CT scan of the brain on the first day after the operation. The volume of the resection cavity and the volume of blood were documented.
Results:
We could show that the volume of the tumor had a significant effect on the amount of blood in the tumor cavity, whereas VPA medication had no effect.
Conclusions:
In our dataset, we found that tumor size had a significant effect on postoperative blood volume. In contrast, no serious bleeding complications occurred in the patients receiving VPA. Therefore, the present study does not provide any evidence for the need to discontinue VPA medication prior to and during surgery.