The present research aims to point out the long-existing defect of analyzing the spectrum diagram only from the perspective of haemodynamics instead of haemorheology. In the light of the theories of haemodynamics and haemorheology, the causes of spectrum diagram formation of carotid artery blood at the rapid and slow flow can be clarified completely and accurately. Four conclusions have been drawn in the end. As long as the velocity gradient is large enough, obvious red blood cells concentrate to the shaft even in the big or bigger blood vessels; the spectrum diagram is the powerful proof of the two phase flow model of blood; the spectrum diagram can be completely and accurately analyzed only by combining haemodynamics with haemorheology; and only when the red blood cells concentrate to the shaft, the big or bigger blood vessels can be regarded as haemogeneous fluid.
The experiment was earied out on the a boomen of the whiterats. The epigastric vein wasarterialized by means of anastomcois with the femoral artery, lateral thoracic vein was reserved as aefferent vessel. The changes of hemorheology were mesured after arterialization, and were comparedwith the changes in the normal A-V skin flaps. The levels of platelet, aggreation, blood viscosityand plasma fibrinogen in arterialized vein flape were signmeantly higher than that in A-V flaps. ASa r...
Objective To investigate the early diagnosis of lower l imb deep vein thrombosis (DVT) after major orthopedic surgeries. Methods From October 2005 to June 2009, color doppler sonography and hemorheology detection were carried out for 62 cases undergoing first total hip arthroplasty (THA), 14 cases undergoing total knee arthroplasty (TKA), and 86 cases undergoing hip fractures surgery (HFS) before operation and 1, 7, 14 days after operation. The plasma D-dimerlevels of the DVT were also examined for the THA patients before operation and 3 days after operation. Of all cases, therewere 89 males and 73 females, aged from 34 to 74 years (51.5 years on average). After operation, all the patients were treated with the regular low molecular weight heparin sodium against DVT. Results After operation, 17 cases (10.5%) developed DVT, including 8 THA cases, 1 TKA case, and 8 HFS cases. Preoperative color doppler sonography showed no abnormal echo, normal b blood flow signal, and normal periodical variation in vein blood flow without regurgitation. Postoperative examinations showed that the vascular occlusion of common femoral vein and popl iteal vein occurred in DVT patients. There were significant differences (P lt; 0.05) in whole blood viscosity between patients with DVT and without DVT after 1, 14 days and no significant difference (P gt; 0.05) before operation and 7 days after operation. There was no significant difference (P gt; 0.05) in plasma viscosity and erythrocyte aggregation index, between patients with DVT and without DVT pre- and postoperation. There was significant difference (P lt; 0.05) in erythrocyte deformation index between patients with DVT and without DVT 14 days after operation. The preoperative plasma D-dimer levels of patients with DVT and without DVT were (372.00 ± 148.62) ng/mL and (369.00 ± 141.03) ng/mL, respectively, showing no significant difference (P gt; 0.05); the 3 days postoperatively levels were (574.00 ± 217.29) ng/mL and (391.00 ± 120.16) ng/mL, respectively, showing significant difference (P lt; 0.05). Conclusion Color doppler sonography in combination of hemorheology and plasma D-dimer examination can be beneficial for the early diagnosis of DVT in major orthopedic surgeries.
In order to investigate the influence on the blood flow direction and pattern at the arterial bifurcation, the mesenteric arterioles of 19 SD rats were observed under the OLYMPUS BH2 surgical microscope. After the rats were anesthetized and the body temperature was kept at 37℃ to 38℃, the mesenteric membrane wasexposed and the pattern and direction of the blood flow of the arterioles whichbifurcated at angle of 45±5°, 90±5° and 135±5° were observed. Results showed that the deformation of RBCs made them easy to adapt to the intravascular geometry and pass by fluently without sticking. It was implied that the alteration in arterial flow direction did not cause turbulance at the bifurcation site, and this in return suggested that in end-to-side anastomosis of small arteries,the flow volume would not be reduced and the chance of thrombosis would not be increased.
Abstract:Objective To evaluate the effects of modified uhrafihration (MUF)on blood rheology in infants after open cardiac surgery. Methods According to admission number, 22 infants of body weight less than 10 kilograms with ventricular septal defect (VSD) and pulmonary hypertension (PH) were divided into control group (10 infants, the mantissa of their admission number was odd number) and experimental group (12 infants, the mantissa of their admission number was even number). Cases in control group didn't undergo MUF at the end of cardiopulmonary bypass (CPB), while cases in experimental group underwent MUF; the flow rate of MUF ranged from 10 ml/min · kg to 15 ml/min · kg. MUF lasting for 10-15 minutes. Blood samples were repeatedly collected as following time: before operation, at the end of CPB, 15 minutes after CPB or the end of MUF, 2, 24 h after operation. Blood sample of 2. 5 ml was collected from the radial artery with hepathrom test-tube. The changes of relative indexes of the blood rheology were observed by MDK-3200 completely automatic dual pathways blood rheology testing analysator at 37±1 C. Results Hemoglobin, hematocrit, red cell count, blood yielding stress, plasma viscosity, the whole blood viscosity at high shear rate, the whole blood viscosity at middle shear rate and low shear rate, the whole blood reduction viscosity at high shear rate and middle shear rate, the whole blood reduction viscosity at low shear rate and Casson viscosity in experimental group at the end of MUF were significantly higher than those in control group at 15 minutes after CPB (P〈0. 05). There was no significant difference in red cell aggregation index and red cell deformity between two groups at each moment (P 〉 0.05 ). Conclusion Hemoglobin, hematocrit and red cell count are significantly elevated through MUF after CPB. Whole blood viscosity in infants undergone open cardiac surgery after CPB with MUF is higher than those who didn't undergo MUF.
Hyperuricemia is a risk factor for various diseases, but knowledge on acute hyperuricemia is still not sufficient. The present study was aimed to investigate the effect of acute hyperuricemia on red blood cells from hemorheological point of view, and to provide the reference for clinical treatment. The rats were gavaged with 500 mg/kg hypoxanthine and intraperitoneally injected with 100 mg/kg oxonate to induce the model of acute hyperuricemia. The same volume of blood samples were drawn within time period of 0, 1, 2, 3 and 6 h, respectively, from the inner canthus of rats to measure the serum uric acid, hemorheological parameters and the malondialdehyde level. It was found that in each period of 1, 2 and 3 h, the rats had significantly higher levels of uric acid. The integrated deformation index and relax index were increased. The hemolysis rate was significantly reduced. The plasma malondialdehyde level was obviously decreased at the end of 2 h. The results suggested that short-term elevated uric acid could improve the hemorheological parameters and the lipid oxidative level in red blood cells.
OBJECTIVE: To study the hemorheology of island flap after ischemia-reperfusion injury and modulation of dexamethasone. METHODS: Sixty Wister rats were made ischemia-reperfusion injury model, and divided into two groups randomly(Group I: intraperitoneal injection of normal saline 2 ml/kg as control group; Group II: intraperitoneal injection of dexamethasone 5 mg/kg as experimental group). Flap survived areas were measured and neutrophil necrosis numbers in flaps were counted. Erythrocytes and neutrophil hemorheology were observed. RESULTS: Area survived flap in group II was larger than that in group I. Neutrophil necrosis numbers were less in group II than in group I (P lt; 0.05). Whole blood hyposhear viscosity, erythrocyte aggregation, Casson yield stress and nerutrophil adhesion ability were higher in group I than in group II (P lt; 0.05); and the neutrophil deformability was lower in group I than in group II. CONCLUSION: Flap inchemia-reperfusion can increase erythrocyte aggregation index and neutrophil adhesion ability. Dexamethasone can improve these and decrease neutrophil necrosis numbers, so as to prevent flap from ischemia-reperfusion injury.