Anemia as a Risk Factor of Hemorrhagic Tendency during Surgery

Objectives: Although it is well-known that a hemorrhagic tendency in patients with massive bleeding during surgery, or with anemia before surgery, is difficult to control, its mechanism is still obscure. Study Design: Using a damped oscillation rheometer, we measured the initiation time (Ti) of whole blood with several concentrations of red blood cells (RBCs) and the Ti of platelet-free plasma (PFP) with various concentrations of RBCs. Results: The Ti of the whole blood became prolonged according to the dilution of the RBC concentration. RBCs could coagulate the PFP, and the Ti of PFP also was prolonged according to the dilution of the RBC concentration. Conclusion: These results suggest that RBCs might have an important role as a phospholipid supplier in the intrinsic pathway of the blood-coagulation mechanism. Anemia could thus represent a risk factor for hemorrhagic tendency during surgery due to lower RBC concentrations.