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PubMed2002

Effects of antihypertensive therapy on hemorheological profiles in female hypertensive patients with initially low or high whole blood viscosity.

This study was designed to examine changes of hemorheological parameters in essential arterial hypertension subjects following antihypertensive drug therapy. Eighty two female subjects were enrolled, and sub-divided into two groups based upon their high shear whole blood viscosity being lower (L) or higher (H) than normal controls. Equal numbers of L and H subjects were then treated for four weeks with one of four agents: angiotensin-converting enzyme inhibitor (ACE-inhibitor, Spirapril - 6 mg/day); calcium antagonist (Isradipin - 5 mg/day); beta-1-blocker (Talinolol - 100 mg/day); diuretic (Indapamide - 1.5 mg/day). Both prior to and following drug treatment for six weeks, hemorheological measurements included plasma viscosity; high and low shear whole blood viscosity, hematocrit, fibrinogen and RBC aggregation. Treatment with each of the four drugs significantly (p<0.05) reduced blood pressure in both the L and H groups. However, the hemorheological effects of antihypertensive drug therapy differed markedly between groups: plasma and whole blood viscosity were significantly elevated in the L groups whereas these parameters were significantly decreased in the H groups. Fibrinogen levels and RBC aggregation decreased in both groups, whereas hematocrit was unaffected. These results thus suggest that the rheologic effects of antihypertensive drug therapy depend strongly on the initial, pre-treatment status of the subject, and that for some subjects, such therapy can result in adverse hemorheological alterations.

Antihypertensive Agents↗
PubMed1992

[Relations between plasma-erythrocyte viscosity factors and ESR].

The ESR is usually put in relationship: to the real density of the RBCs (erythrocytes) (difference between the RBC specific gravity and the plasma one), and to the resistance that the RBCs meet moving in a medium, which is due to the plasma viscosity and to the total external RBC surface. When the RBCs take shape of aggregates, their external surface is decreased and ESR increases. The most important plasma factor causing changes in ESR is the fibrinogen level followed by the plasma globulins and by the products arising from the tissue damage. The resistance that the RBCs meet moving in the plasma is well expressed by the measurement of the plasma-RBC viscosity considering that is inclusive of both factors that are the plasma viscosity and the external RBC surface. The plasma-RBC viscosity is the resultant of several factors: Fa = Fb - Fe - Fs - Fm, were: Fa is the resultant, Fb the attracting forces due to the proteic macromolecules, Fe the repulsing forces due the negative charges. Fs the repulsing forces due to the shear-stress, Fm the force which opposes itself against the surface tension of the aggregation; it depends on the RBC morphology and on the RBC rigidity. The ESR has been recently used like an index of the RBC aggregation. The Authors study the relationship between several hemorheological parameters and the ESR in infective and inflammatory processes.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Sedimentation↗
PubMed2003

[The effect of local vibration on blood-lipids and whole blood viscosity].

OBJECTIVE: To study the effects of local vibration on blood-lipids and whole blood viscosity. METHODS: The total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), whole blood viscosity, apolipoprotein (Apo-), red blood cell (RBC), platelet (PLT), mean corpuscular volume (MCV), serum-protein, postprandial blood sugar (PBS), and serum-protein of experimental and control workers were detected. The difference of the means and abnormal rates of two groups were compared. RESULTS: The means of TG, TC, HDL in exposed group [(1.01 +/- 0.85), (3.25 +/- 0.61), (1.14 +/- 0.20) mmol/L respectively] were significantly lower than that of control group [(1.89 +/- 1.47), (3.87 +/- 0.82), (1.22 +/- 0.26) mmol/L, respectively, P < 0.01 or P < 0.05]. Apo-A was also decreased [(1.13 +/- 0.29) g/L vs (1.23 +/- 0.16) g/L, P < 0.01]. The mean of whole blood viscosity were significantly increased in exposed group [(2.76 +/- 0.42) mPa.s vs (2.54 +/- 0.33) mPa.s, P < 0.01]. The abnormal rate of Apo-A was significantly higher in exposed group (23.30%) than that in control (4.50%, P < 0.01). CONCLUSION: Local vibration may induce decrease in blood lipids, increase in blood viscosity and changes in some other blood parameters.

Adult↗
PubMed1992

Sulodexide oral administration influences blood viscosity and fibrinolysis.

The aim of this study was to verify the effects of oral administration of a new enteric-coated formulation of sulodexide on blood viscosity and fibrinolysis. Six outpatients suffering from peripheral artery occlusive disease were administered orally two enteric-coated tablets containing 50 mg of sulodexide, twice daily for seven days. On the first and seventh administration days, the following parameters were evaluated: plasminogen activator inhibitor (PAI-1) activity, PAI-1 antigen, tissue plasminogen activator (t-PA) and whole blood, serum and plasma viscosity, before (0 time) and 2, 4 and 8 hours after ingestion of the drug. Following the first administration (50 mg), a slight reduction of PAI was registered; after 7 days' administration, a clear-cut lowering of functional and antigenic PAI was observed, together with an increase of t-PA. As to the drug's influence on blood viscosity, after 7 days the most evident reduction was that registered for plasma viscosity. No side effects were observed throughout the treatment period.

Aged↗
PubMed2003

[Comparison of whole blood viscosity in vascular diseases].

The viscosity of whole blood taken from patients suffering from different diseases was studied. The measurements of blood viscosity were performed in the shear rate range 0.01-100 s-1 in three groups of patients. The first group consisted of 60 patients without known cardiovascular disorders referred for a non-vascular minor surgery (patients did not take any drugs influencing vascular system). The second group (30 persons) consisted of patients after cerebral ischemic episode, remaining under permanent medical control. The third group consisted of 100 patients after myocardial infarction. In the group of patients suffering from vascular system disorders (second and third) the blood viscosity has been significantly lower then in the first group. Such results might suggest that in patients with vascular system disorders blood viscosity has been decreased in the way of specific feedback mechanism, whereas the beneficial hemorrheological influence of secondary prevention seems to be questionable.

Aged↗
PubMed1992

Determination of total protein concentration and viscosity of synovial fluid from the tibiotarsal joints of horses.

Viscosity of synovial fluid (SF) from 29 clinically normal horses was determined by use of a rotational cone and plate microviscosimeter. Total protein concentration in the SF of the 29 horses, as measured with a refractometer, was less than 2.5 g/dl. When the Coomassie brilliant blue test was used to determine total protein concentration in SF for 15 horses, the mean value was 1,088 mg/dl. Viscosity values at 60, 30, 12, 6, 3, and 1.5 revolutions/min (rpm) spindle speed were 4.41 +/- 1.54 centipoise (cp), 5.29 +/- 1.94 cp, 6.76 +/- 2.76 cp, 8.52 +/- 4.27 cp. 10.41 +/- 6.30 cp, and 13.07 +/- 9.05 cp, respectively. Synovial fluid viscosity increased with decreasing rpm and shear rate, but the shape of the curve for each horse fitted the asymptotic curve. The rotational cone and plate microviscosimeter was an accurate instrument in measuring SF viscosity at multiple rpm or shear rates in horses. The values obtained on clinically normal horses in this study will serve as a baseline for comparison in the evaluation of horses with joint disease.

Animals↗
PubMed2005

Blood fluidity and outcome after femoropopliteal percutaneous transluminal angioplasty (PTA): role of plasma viscosity and low platelet count in predicting restenosis.

Rheological abnormalities are well known in patients with peripheral arterial occlusive disease (PAOD). We wanted to determine whether rheological variables are related to restenosis after femoropopliteal percutaneous transluminal angioplasty (PTA). In 114 patients (62 men; median age 70 years) undergoing femoropopliteal PTA for symptomatic peripheral arterial occlusive disease (PAOD) plasma viscosity, red cell aggregation, whole blood viscosity, hematocrit, fibrinogen, platelet count, leukocytes and C-reactive protein were determined the day after the procedure and at 1, 3, and 12 months. The primary endpoint was restenosis >50% documented by duplexsonography up to 12 months. Cox proportional hazards analysis was used to assess the risk of restenosis for postinterventional values of rheological variables. Forty-eight patients (42%) developed restenosis at 12 months. Patients with restenosis had higher baseline plasma viscosity (PV) (medians, 1.71 vs. 1.65 millipascal seconds [mPa.s]; p = 0.04) and lower platelet count (224 vs. 240 x 10(3)/microl; p = 0.03) than patients without restenosis. The hazard ratio (HR; 95% CI) of incident restenosis was 9.2 (1.12-76; p = 0.03) for PV and 0.99 (0.99-1.0; p = 0.07) for PLT. When examining jointly both high PV and low platelet count (PLT), patients with PV > 1.66 mPa.s and PLT < 233 x 10(3)/microl (i.e. variables split at their respective median) had an increased risk of restenosis (log-rank test p = 0.01). Multivariate Cox proportional hazard analysis showed that plasma viscosity (p = 0.02), low platelet count (p = 0.01), lesion length (p = 0.0037) and lack of hypertension (p = 0.01) were associated with restenosis at 12 months. No associations were found between restenosis and the other rheological and inflammatory variables studied. Our data suggest that increased PV and low PLT contribute to restenosis after femoropopliteal PTA.

Aged↗
PubMed1992

[Raynaud's phenomenon and blood viscosity].

Raynaud's phenomenon is mainly linked with cold provoked vasomotor perturbations, but also with rheological alterations since blood viscosity is enhanced by lowering temperature. Several methods are available for studying distal vascularization: peri-ungual capillaroscopy, digital plethysmography and laser-Doppler. Digital arteriography must be reserved to serious ischemia regarding the general anesthesia needed to avoid spasm. All these methods explore especially the vessel wall. Conservely, blood viscosity which has been developed for 25 years investigates the content of the vessel. Since 1965, numerous hemorheological studies pointed out the rheological disorders, especially those concerning plasma and blood viscosity. The most usual viscometry abnormalities revealed erythrocyte hyperaggregation, red cell hypodeformability, blood and plasmatic hyperviscosity. In a comparative study, 46 patients with Raynaud's phenomenon were studied: we performed peri-ungual capillaroscopy, plethysmography and viscosity measurements. The results demonstrated a link between capillaroscopy and thixotropy. Both investigations are never normal at the same time in connectivites and never abnormal at the same time in Raynaud's disease (primary Raynaud's phenomenon). In conclusion hemorheological studies showed nearly normal rheological parameters in Raynaud's disease, but abnormal rheological parameters in secondary Raynaud's phenomenon.

Adult↗
PubMed2005

Effect of inoculum and sludge concentration on viscosity evolution of anaerobic granular sludges.

The rheological behaviour of granular sludges (diameter 20-315 microm) originating from different anaerobic reactors was carried out using rotation tests. The sieved granular sludges suspensions display a non-Newtonian rheological behaviour and the limit viscosity was therefore used as a rheological parameter. The values obtained, which depend on the shear rate used, were strongly influenced by the total suspended solids (TSS) content of granular sludge and an exponential relation was found between the TSS and the rheological parameter limit viscosity. The increase of viscosity as a function of TSS content of the granular sludge as well as the increase of granule size underlines the importance of the interaction between granules in the evolution of this rheological parameter. Significant differences in granular sludge limit viscosity were found for granular sludge of different origins. All measurements performed with 10 g.l(-1) TSS granular sludge indicate the ability of the chosen rheological parameter to describe different granular sludge quality.

Bacteria, Anaerobic↗
PubMed2005

Measurement of whole blood viscosity profiles via an automated viscometer: technical details and clinical relevance.

Recent basic science and large-scale clinical studies involving blood rheological factors have led to a similar conclusion: the mechanics of blood flow play an important role in the development and progression of various cardiovascular diseases (e.g., coronary artery disease, stroke). Several viscometer systems to measure whole blood viscosity have been developed, yet blood viscosity measurements are not routinely employed in clinical practice, primarily due to the complexity of currently available methods. Herein we provide a description of a new, computer-controlled capillary viscometer that offers a convenient approach to the measurement of blood viscosity over a wide range of shear rates. The new viscometer uses a disposable test section, requires small volumes of blood, provides viscosity data that compare well with those from other viscometers, and completes all testing and data analysis within five minutes.

Blood Viscosity↗
PubMedDate not supplied

Comparison of plasma viscosity and fibrinogen concentration in hypertensive and normotensive diabetics.

BACKGROUND: Body weight, body mass index, fibrinogen concentration and relative plasma viscosity can contribute to the development of hypertension in diabetics. This study compares body weight, body mass index, fibrinogen concentration and relative plasma viscosity between hypertensive diabetics, normotensive diabetics and healthy controls. METHODS: The present study was carried out on normotensive and hypertensive diabetics taken from medical OPD of Saidu group of teaching hospitals, Swat. A group of healthy male subjects between 30-60 years of age from the staff members of Saidu Medical College, Swat was also included. Each group comprised of 35 subjects. Systolic and diastolic blood pressures, body weight, height, body mass index, fibrinogen concentration and relative plasma viscosity were measured and compared. RESULTS: Body weight, body mass index, fibrinogen concentration and relative plasma viscosity were all significantly more in hypertensive diabetics than normotensive diabetics and healthy control subjects. CONCLUSION: The onset of the complications is different in the two groups of diabetics (hypertensive and normotensive), earlier in hypertensive diabetics and delayed in normotensive diabetics.

Adult↗
PubMed1990

Variability of plasma viscosity in monoclonal IgM gammopathies.

Hyperviscosity syndromes can caused by both plasmatic and cellular factors. We have studied 20 patients affected by IgM gammopathy of different origin and 12 healthy subjects matched for sex and age, in order to evaluate the relation between paraprotein levels and plasma viscosity. We have observed a significant plasma viscosity increase only in 14 patients with monoclonal IgMk gammopathy. In the same patients was also evident an hyperviscosity syndrome. In the other 6 patients, with monoclonal IgM or polyclonal gammopathy and without clinical symptoms, plasma viscosity was only slightly increased. We have also observed a significant correlation between IgM and light chains (kappa, lambda) serum level and increased plasma viscosity. These results suggest that one can't consider all IgM gammopathies as cause of hyperviscosity syndrome.

Aged↗
PubMedDate not supplied

[Intra- and postoperative changes in blood viscosity].

Blood and plasma viscosity has been controlled in a group of patients undergone to aorto-iliac reconstruction and in a group of control after thyroidectomy, cholecystectomy, and hernioplasty. The hemodilution induced by intraoperative infusion in the vascular reconstruction produced an important decrease of hematic and plasmatic viscosity which lasted for several days after the operation. Removing the hemodilution effect by a mathematical correction of the viscosity measured values to a standard haematocrit, it has demonstrated as surgical operation, apart from its entity, promoted an increase of the viscosity which persisted long in the postoperative course. For what it concerns the risk of postoperative thrombosis from one side protective effect of hemodilution is confirmed, from the other, in absence of the hemodilution, it would be useful to continue the antithrombotic prophylaxis longer the perioperative time as usual.

Aged↗
PubMed1991

Effect of hydroxyurea on blood viscosity in chronic myelogenous leukemia with hyperleukocytosis.

The effect of hydroxyurea on blood viscosity was studied in 10 patients with Philadelphia chromosome positive chronic myelogenous leukemia (CML) and hyperleukocytosis (white blood cell counts over 200 x 10(9)/l). All the patients had visible manifestations of leukostasis such as headache, blurred vision, retinal hemorrhage, pulmonary infiltrates, etc. Contraves LS 30 viscometer was used to measure the blood viscosity at 37 degrees C and at different shear rates on paired leukemic blood samples obtained before and after the hydroxyurea treatment. The blood viscosity was significantly higher in CML patients then normal subjects and decreased after treatment with hydroxyurea. In all the cases plasma viscosity was unaffected by the treatment.

Adolescent↗
PubMed1991

[Blood and plasma viscosity versus claudication distance in patients with obliterative atherosclerosis of the lower limbs].

The aim of the investigations was to show the influence of increased blood and plasma viscosity on the claudication distance in patients with obliterative atherosclerosis of lower limbs. The investigations were carried out in 53 patients: 41 men and 12 women (group I, age 45-67 years). The control group consisted of 100 healthy persons (group II) with similar range of age. The rheological studies of blood were carried out by low-shear 100 Contraves viscometer, the plasma viscosity--by means of capillary viscometer. Moreover, the total lipids, alpha, pre-beta, beta-lipoproteins, triglycerides, total cholesterol, free fatty acids, fibrinogen and hematocrit of the blood were determined. The blood for above mentioned estimations was collected before testing of the claudication distance. A significant increase of blood and plasma has been shown as well as an increase of total lipids, fibrinogen, triglycerides, total cholesterol, free fatty acids. The alpha lipoproteins were significant decreased in patients with intermittent claudication compared to the controls. The claudication distance ranged 10-500 m (the mean: 143 +/- 119 m). The correlation between claudication distance and blood and plasma viscosity was significantly negative (r = -0.42, p less than 0.001 and r = -0.32, p less than 0.05 respectively). The obtained results indicated that an increase of blood and plasma viscosity in patients with obliterative atherosclerosis of lower limbs was correlated to the decrease of claudication distance.

Aged↗
PubMed1991

Relationships of plasma viscosity, coagulation and fibrinolysis to coronary risk factors and angina.

Plasma viscosity, molecular markers of activated coagulation and fibrinolysis (fibrinopeptides A and B beta 15-42), coagulation factors (fibrinogen and factor VII) and antiplasmins were measured in 529 men aged 35-54 years and related to new angina pectoris (n = 117) and to coronary risk factors in controls without angina (n = 412). Five major risk factors (cigarette-smoking, blood pressure, cholesterol, triglyceride and body mass index) were each associated with increases in plasma viscosity, coagulation factors, and imbalance of coagulation over fibrinolysis (increased ratio of fibrinopeptide A/fibrinopeptide B beta 15-42). Increased viscosity and fibrinogen in smokers were partly reversed in ex-smokers, but the imbalance of coagulation and fibrinolysis persisted. Cholesterol and triglyceride were also associated with increased antiplasmin activity. In men with angina, only fibrinogen was elevated compared to controls. We suggest that increased plasma viscosity and an imbalance of coagulation over fibrinolysis may be mechanisms by which known risk factors promote arterial thrombosis, but are not present in stable angina.

Adult↗
PubMed1990

[The anti-hemorrhagic shock of acupuncture on neiguan and its effect on the cardial pump function and the blood viscosity].

The purpose of this paper is to study and analyse the effects of the cardial pump function and the blood viscosity on rabbits with hemorrhagic shock by puncturing Neiguan. In the experiment 30 rabbits were divided into the electroacupuncture (EA) group and the control group, each group was 15 rabbits. The cardial pump function, the blood pressure and the blood viscosity were recorded during normalize, shock, and EA. The results were as following. 1. The blood pressure of the rabbits which were in hemorrhagic shock was raised by needling Neiguan. MAP was raised from 43 +/- 8 to 87 +/- 15 mmHg (p less than 0.001). 2. The cardial pump function were reinforced by needling Neiguan. SV was increased from 0.41 +/- 0.46 (before EA) to 0.73 +/- 0.12 ml (p less than 0.0001). CO, SI, CI. and WL were improved in a certain degree with difference significant. In the EA group the each index of the cardial pump function was higher than that of the control group. There was statistical significant between the two groups. 3. Needling Neiguan, the blood viscosity was tending to normality. The blood plasma viscosity was increased. There was significant difference (p less than 0.05). These results suggest that needling Neiguan may protect the cardial pump function, raise the blood pressure, play a positive role during anti hemorrhagic shock.

Acupuncture Points↗
PubMed1990

[Blood and plasma viscosity and the distance of intermittent claudication in patients with type II diabetes and thrombophlebitis].

In 49 patients with insulin-resistant diabetes, with ischaemia of the lower extremities blood viscosity was measured at low coagulation rates and plasma viscosity was determined also. Moreover plasma measurements were done of total lipids, alpha-, pre-beta-, and beta lipoproteins, triglycerides, total cholesterol, free fatty acids, and, besides that, the hematocrit was measured. Immediately after blood sampling for rheological and biochemical investigations the distance of intermittent claudication was measured. A rather considerable increase of blood and plasma viscosity was noted in the patients in comparison with controls, other findings included disturbances of lipid metabolism, increased fibrinogen level, and a negative correlation between the distance of intermittent claudication and blood and plasma viscosity.

Aged↗