Search

Several issues concerning the biocompatibility) testing of medical devices as stated in European directive 90/385 and 93/42 are discussed. The authors describe the fundamental characteristics that biomaterials should have to be employed in the human body, the assays useful for testing different aspects of biocompatibility and the harmonized regulations already available or under development. The testing protocol applied by the a. in their Lab covering many issues of biocompatibility is presented: a body of experience was gained over the years and it has been revised under the new regulatory items. In conclusion, the biocompatibility of devices must be assessed following the European harmonized standards, the available. Where proper standards are still lacking, feasible testing methods, even if not officially adopted yet, have to be used.

The authors have quantitatively evaluated and compared in vitro the Staphylococcus aureus and Staphylococcus epidermidis strain adhesiveness on various types of silicone used in surgery. The results show that there are some adhesiveness differences between the two assayed strains (S. epidermidis adhesiveness > S. aureus adhesiveness) and among silicone types (adhesiveness on soft silicones > adhesiveness on hard silicones). However all silicones are suitable substrata for in vitro bacterial adhesion.

The authors have examined the alterations in the coagulation pathway of plasma filtered through a polyester filter coated by a hydrophilic polymer. The activation of the coagulation pathway was evaluated by measuring prothrombin time, activated partial thromboplastin time, coagulation factors and fibrinopeptide A. The results obtained demonstrate that the examined filter does not induce significative activation of the coagulation pathway.