Rationale and objectives: We used a global screening device that operates under physiologic flow conditions to monitor the effects of ionic and nonionic contrast media (CM) on hemostasis.
Methods: This flow dynamic technique perfuses unanticoagulated whole blood through a hollow fiber. A leak in the fiber is created by a precision needle, and the resulting pressure fluctuations within the fiber are monitored to examine the ability of the hemostatic system to close the leak by forming a stable platelet plug.
Results: Both ionic and nonionic CM (25% CM/blood, v/v) were shown to lengthen the mean in vitro bleeding times (IVBTs) compared with normal blood. Ionic CM (ioxaglate and diatrizoate) consistently produced IVBTs longer than 30 min. The nonionic CM iopamidol, iohexol, and ioversol gave mean IVBTs of 16.43, 17.63, and 19.84 min, respectively.
Conclusion: Of the three nonionic CM tested, iopamidol had the greatest probability (31%) of producing an IVBT in the normal range, with probabilities of 5% and 7% for iohexol and ioversol, respectively. Thus, iopamidol offered the least anticoagulant effect among the ionic and nonionic CM we studied.