Improved Method for the ASTM Platelet and Leukocyte Assay: Use of Minimal Heparinization in a Screening Test for Hemocompatibility of Blood-Contacting Medical Devices

Most blood-contacting medical devices must be assessed for potential thrombogenicity prior to regulatory approval. A common assay for screening and qualifying devices involves monitoring the reduction of platelet and leukocyte (P&L) counts in whole blood exposed to the device. We have validated an improved method for assessing a device's effect on platelet activation and surface adhesion, offering significant improvement over the current ASTM F2888-13 method, which uses blood fully anticoagulated by acidified citrate (known to significantly inhibit platelet responsiveness). Our method uses minimal heparinization (final concentration 1  IU/mL) to optimize the response to commonly used control materials: latex, black rubber, and high-density polyethylene (HDPE). We also have shown the assay's capacity to appropriately assess a legally marketed comparator device (LMCD) with a documented clinical history. The test materials were pr epared for incubation and allowed to remain in contact with the citrated or heparinized blood for ∼1 h at 37 °C. A complete blood count was performed prior to exposure, and at the end of the incubation period, reductions in P&L counts were recorded. Results from citrate-anticoagulated assay showed only a marginal response to the positive control, black rubber. Using heparinized blood, the assay generated a robust response to the positive controls, the “intermediate scoring” controls, and also assessed a legally marketed and approve...
Source: Journal of Medical Devices, Transactions of the ASME - Category: Medical Devices Source Type: research