Study On The Effect Of Calcium Alginate Dressing On Hemostasis And Hemostasis In Vitro

Objective To preliminarily study the hemostatic effect in vitro and hemostatic mechanisms of calcium alginate dressing.Methods Venous blood from the healthy volunteers was blended with 38 g/L sodium citrate by 1:9 volume ratio. The hemostatic effect of calcium alginate dressing was examined by the result of dynamic coagulation test, nasopore dressing, medical cotton gauze and blank groups were used as control. A volume of 1ml human sodium citrate anticoagulant blood was respectively dropped on calcium alginate dressing,nasopore dressing and medical cotton gauze. After 2 minutes of standing at the room temperature, the interaction between materials and blood was observed using scanning electron microscopy. The red blood cells were isolated and suspended at a hematocrit of 40%. A volume of 1ml human red blood cell suspension was dropped to5 mg of calcium alginate dressing, nasopore dressing and medical cotton gauze respectively. After 15 seconds of standing, washed the materials with normal saline.Then added 1ml normal saline to the materials and incubated for 1 hour at room temperature. The interaction between materials and red blood cells were observed using scanning electron microscopy. A volume of 1ml human red blood cells were suspended by different concentrations(10 g/L, 5 g/L, 2.5 g/L) of calcium alginate dressing extract to observe the erythrocyte sedimentation rate at different time points(30min,60 min,120 min). Smeard the red blood cell suspension and observed the aggregation degree of red blood cells under microscope, normal saline group was used as blank control group. Platelets rich plasma(PRP) was isolated. PRP was incubated with different concentrations(10 g/L, 5 g/L, 2.5 g/L) of calcium alginate dressing extract at 37 ?,then CD62 P positive platelet percentage was measured by flow cytometry. PRP was loaded with Fura-3, AM at 37?, then washed the plasma and added different concentrations(10 g/L, 5 g/L, 2.5 g/L) of alginate dressing extract,incubated at 37 ?. Then observed the fluorescence of calcium ions in platelets by laser scanning confocal microscope.Results The results of dynamic coagulation test demonstrated that calcium alginate dressing can significantly accelerate the coagulation process, the effect is better than that of nasopore dressing and medical cotton gauze. Dense fibrin network was formed after calcium alginate dressing contacting with sodium citrate anticoagulation blood.A large number of blood cells were recruited. There were only a small amount of red blood cells and platelets adhesion in the nasopore dressing and medical cotton gauze groups. After the calcium alginate dressing interacting with red blood cells, red blood cell deformability was visible, with a pseudopodia-like change. The red blood cell morphology unchanged in the nasopore dressing and medical cotton gauze groups.The extract of calcium alginate dressing was dose-dependently and time-dependently increased the red blood cells aggregation, comparative differences between groups was statistically significant(P < 0.01). It was found that the calcium alginate extract could promote rouleaux formation of erythrocyte. The extract of calcium alginate dressing was dose-dependently enhanced the CD62 P positive platelet percentage,comparative differences between groups was statistically significant(P < 0.01). With the concentrations of calcium alginate dressing exact increasing, the fluorescence intensity of calcium ions in platelets increasing.Conclusion These results demonstrate that calcium alginate dressing can effectively promote blood coagulation. It promotes hemostatic process by releasing of calcium ions, causing red blood cells aggregation and activating red blood cells and platelets.It fully shows that the dressing has a high clinical value in the treatment of bleeding.