# Dynamic and Quantitative Assessment of Blood Coagulation Status with an Oscillatory Rheometer
## 3 Results
### Antagonising Heparin with Equimolar Concentrations of Proamine
Despite the CT not being significantly different between protamine-antagonised heparin samples and non-heparinised control, the linear slopes of these antagonised samples were significantly different from the control (Figure A8a) indicating a slight shift towards a slower coagulation process than without any heparin or protamine, which is not detectable in the CT. However, the slopes of elastic and viscous shear moduli of the antagonised samples were still significantly different from the heparinised control. The mean of elastic and viscous shear moduli at 300 s, indicative of clot firmness, yielded similar tendencies between samples as the CT. All heparin concentrations with their equimolar protamine concentrations were not significantly different from the mean control without heparin (Figure A8b). The heparinised control (1 IU/mL heparin) only showed a significantly reduced mean  
Figure 3: Citrated blood was heparinised and antagonised with protamine before activation with Thromborel. The effect of the inhibitor heparin was reversed by the equivalent amount of protamine. Citrated blood (orange) and a heparinised (1 IU/mL) citrated blood (black) activated with Thromborel were the reference measurements. All protamine-neutralised heparin concentrations provided results comparable to the reference measurement of citrated blood without heparin (orange) (\(n=5\)). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Sample** & **Kineus Pro** & **KC 1A** & & & **Kineus Pro** & \\ \hline  & **CT/n** & **CT/s** & **G\({}^{\prime\prime}\)****(Paal 300 s** & **G\({}^{\prime\prime}\)****(Paal 300 s** & **m (G\({}^{\prime\prime}\)/Pa s\({}^{-1}\))** & **m (G\({}^{\prime\prime}\)/Pa s\({}^{-1}\))** \\ \hline Control & \(23.7\pm 1.6\) & \(21.4\pm 2.9\) & \(22.7\pm 4.3\) & \(2.0\pm 0.5\) & \(72.3\times 10^{-2}\pm 7.5\times 10^{-2}\) & \(16.1\times 10^{-2}\pm 3.0\times 10^{-2}\) \\ \hline \(1\) 0 IU/mL heparin & \(83.3\pm 4.2\) & \(79.0\pm 5.6\) & \(2.1\pm 0.05\) & \(0.7\pm 0.07\) & \(7.8\times 10^{-3}\pm 2.2\times 10^{-3}\) & \(5.3\times 10^{-3}\pm 1.2\times 10^{-3}\) \\ \hline \(1\) 0 IU/mL heparin & \(25.8\pm 0.9\) & \(24.3\pm 3.5\) & \(21.5\pm 3.8\) & \(1.9\pm 0.3\) & \(39.0\times 10^{-2}\pm 4.0\times 10^{-2}\) & \(8.1\times 10^{-2}\pm 3.3\times 10^{-2}\) \\ \hline \(2\) 0 IU/mL heparin & \(26.9\pm 1.3\) & \(25.4\pm 4.1\) & \(24.1\pm 2.4\) & \(2.2\pm 0.4\) & \(42.7\times 10^{-2}\pm 5.0\times 10^{-2}\) & \(9.5\times 10^{-2}\pm 0.7\times 10^{-2}\) \\ \hline \(3\) 0 IU/mL heparin & \(25.9\pm 1.3\) & \(24.7\pm 4.5\) & \(23.5\pm 3.6\) & \(2.1\pm 0.1\) & \(51.0\times 10^{-2}\pm 3.2\times 10^{-2}\) & \(11.0\times 10^{-2}\pm 0.1\times 10^{-2}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Citrated blood activated by Thromborel (Control) and various concentrations of heparin neutralised with the equimolar amount of protamine were equally activated by Thromborel (\(n=5\)). Summary of the clotting time (CT), elastic (G\({}^{\prime}\)) and viscous (G\({}^{\prime\prime}\)) shear moduli at 300 s and linear slopes (m (G\({}^{\prime}\)) and m (G\({}^{\prime\prime}\))). elastic shear modulus at 300 s compared the non-heparinised control and the protamine-antagonised samples, while the viscous shear modulus was not significantly different between the samples. The oscillatory rheometer is capable to detect the antagonising of heparin with the equimolar concentration of protamine. The next experimental step was the titration of various protamine concentrations to a fixed heparin concentration, to obtain by titration the current heparin concentration in the blood sample.