Abstract
Tacrolimus is widely used as an immunosuppressive drug. For the best clinical outcomes, it is important to keep the blood concentration constant. Tacrolimus is continuously infused using polyvinyl chloride (PVC) tubes for patients undergoing hematopoietic stem cell transplantation in the Department of Pediatrics of Okayama University Medical School. This method causes a fluctuation in the patients' blood concentrations. We found that it was difficult to maintain a constant blood concentration. We assumed that their blood concentrations were affected by the absorption of tacrolimus by the PVC tubes. In this study, we showed that a large amount of tacrolimus was absorbed by the PVC tubes and that changes in the patients' blood concentrations were caused by the absorption of tacrolimus by the PVC tubes. We clarified that tacrolimus was not absorbed by polybutadiene (PB) tubes, and the patients' blood concentrations were well controlled by PB tubes. Regarding risk management, our findings suggest that the tubes which do not absorb tacrolimus, should be selected when administering continuous infusion of tacrolimus.
