[Mesenteric circulation evaluation during myocardial revascularization with different temperature modes of extracorporeal circulation].

The Mesenteric blood circulation during myocardium revasculization was investigated 40 patients were divided in 2 groups: 1st group - normothermia CPB, 2nd group hypothermia CPB. It was found that reduced mesenteric perfusion occurred in both groups, but it was more pronounced in hypothermia CPB group and was caused by a significant deterioration of the microcirculation.

[The influence of cardiosurgical intervention type and conditions of artificial blood circulation of perioperative dynamics of cardiac biomarkers].

125 patients after cardiac surgery operated on with the use of artificial blood circulation (ABC) were followed-up. Blood levels of cardiac protein, binding aliphatic acids and troponin 1 and 3 days after the operation were registered. The study showed that aorta clamping more then 90 minutes and hypothermic perfusion regimen influence cardiomyocites negatively. The state of "surgical trauma" and reperfusional myocardium damage was approximately the same during aortic surgery, myocardium revascularization with the use of aortic clamping and cardioplegia, and correction of the acquired heart disease, according to the dynamics of the studied proteins in blood. The minimal blood level of cardiac protein, binding aliphatic acids after coronary by-pass surgery on the working heart witnesses about negative influence of crystalloid hypothermic cardioplegia on coronary microcirculation.

[The characteristics of hemostasis system disorders in a female patient with syndrome of differentiated dysplasia of connective tissue].

The article discusses the data concerning the homeostasis system in patients with syndrome of differentiated dysplasia of connective tissue, in particular, under the Marfan syndrome. The description of clinical case is provided. The analysis of blood coagulation system in female patient operated on the occasion of dissecting intramural aneurysm of aorta as manifestation of Marfan syndrome is discussed.

[The efficacy and safety of tranexamic acid and epsilon-aminocapronic acid in cardiac surgery under extracorporeal circulation].

Sixty patients who had undergone cardiosurgical operations under extracorporeal circulation (EC) were enrolled in the study. All the patients were divided into 2 groups: (1) 40 patients were injected tranexamic acid (TA) (its loading dose was 15 mg/kg; maintenance infusion 1 mg/kg/h throughout the operation; 500 mg in the primary packing volume for an EC apparatus (EA); (2) 20 patients received epsilon-aminocapronic acid (ACA) (its loading dose was 5 g; 5 g in the primary packing volume for an EA and 10 g for infusion after EC). The effects of TA and ACA on the fibrinolytic system were evaluated from the time of XIIa-kallikrein-dependent fibrinolysis (sec) and the concentration of D-dimer (mg/ml). The hemocoagulation system (activated partial thromboplastin time, thrombin clotting time, prothrombin time with the determination of the international normalized ratio, fibrinogen) was studied. The thromboelastogram (the time R, K, and alpha-angle, MA) was analyzed. The indices were determined at the beginning and end of, and 12 hours after surgery. The analysis of the clinical efficacy and safety of the agents was based on the following perioperative data: the incidence of adverse reactions and complications associated with the administration of the agents, the frequency and amount of transfused donor blood components, the volume of blood loss, and the rate of resternotomies. The laboratory and clinical findings lead to the conclusion that TA (Tranexam, OOO "MIR-PHARM") has a 4-fold antifibrinolytic activity as compared with epsilon-ACA. The more pronounced TA-induced suppression of fibrinolysis affects the clinical course of a perioperative period in this group, which manifests itself as a reduced blood loss volume during and after surgery and a lower frequency of use of donor blood elements. By taking into account these data, TA may be recommended as one of the blood-preserving technology components during cardiosurgical operations under EC.

[Use of a potassium and magnesium asparaginate solution to maintain the balance of potassium and magnesium during cardiosurgical interventions under extracorporeal circulation].

The study included 42 patients with coronary heart disease operated on the coronary arteries. A potassium and magnesium asparaginate (PMA) solution, 450-1000 ml, was injected in 30 patients for 5-7 hours; other crystalloid solutions was used in a control group (n = 12). The concentrations of potassium and magnesium were measured prior to surgery, following initial anesthesia, before and after extracorporeal circulation (EC). The measurements suggested a significant potassium and magnesium intake at surgery under EC. The use of PMA solution showed its advantage in stabilizing the study electrolytes at the main surgical stages. Inclusion of PMA into infusion therapy considerably reduced a need for an additional use of concentrated KCl solution to maintain potassium at the preoperative level. Of particular importance was the use of PMA to maintain magnesium that was held in the upper normal range throughout the operation, as shown by both the median values and an individual analysis. When PLA was not administered, the mean concentration of magnesium was consistent with that in the lower normal electrolyte range and 50% patients developed hypomagnesemia. The comparative analysis of the clinical course after EC in both groups of patients with different levels of magnesium was indicative of the better status of some hemostatic parameters with the level of magnesium being maintained in the upper normal range.

[Conditions of artificial blood circulation and erythrocytic aggregation in cardiosurgical patients].

Normothermic artificial circulation, irrespective of its duration, enhances erythrocyte aggregation in response to noradrenaline stimulation. Short-term hypothermic perfusion reduces adrenergic aggregation of erythrocytes while in long-term hypothermic artificial circulation changes in erythrocyte adrenergic aggregation are not significant. In the course of cardiosurgical operation in conditions of artificial circulation adrenergic erythrocyte aggregation undergoes changes: a maximal rise before perfusion, linear lowering and rise to the preoperative level. If perfusion lasts longer than 90 min adrenergic aggregation of erythrocytes sharply and significantly falls. This aggregation depends little on hematocrit, but if it falls under 15% aggregation becomes significant which may be of importance in blood loss arrest in massive blood loss, hemodilution, dilution of coagulation factors and marked thrombocytopenia. In such conditions erythrocyte aggregates may seal damaged microvessels acting as hemostatic lock.

[Comparative assessment of criteria for postoperative renal dysfunction in cardiosurgical patients].

The paper presents data on comparison of the detection rate of renal dysfunction after cardiac surgery, by using the criteria developed by Cockroft-Gault, C. M. Mangano, L.-G. Andersson, and G. Zanardo. It is shown that it is expedient to calculate creatinine phosphokinase by the Cochroft-Gault formula that using a patient's individual parameters provides a more objective approach to making the diagnosis of renal dysfunction. The rate of development of renal dysfunctions in patients who have undergone cardiac surgery under extracorporeal circulation (EC) depends on the type of an operation and the duration and temperature of perfusion. By postoperative day 14, renal function became normal in the vast majority of patients. Renal function became chronic in 1% of the patients operated on the heart under EC.

[Comparative assessment of using various glomerular filtration rate calculations in cardiological patients].

The paper gives the data of comparing the use of various formulas to calculate glomerular filtration rate (GFR) for the evaluation of postoperative renal function in cardiosurgical patients. GFR is shown to evaluate renal filterability with a high degree of reliability. Monitoring of GFR changes may characterize the progression of renal diseases. This indicator is an important predictor of the onset of renal insufficiency and the risk of complications due to chronic renal disease. Calculation of GFR in clinical practice enables the agents excreted owing to glomerular filtration to be dosed to prevent their potential toxicity.

[Impact of protamine sulfate on hemostasis system after operations with artificial circulation].

Effects of different doses and lots of protamine sulfate on hemostasis system after cardiac operations with artificial circulation are analyzed. Overall 982 patients underwent cardiac operations with artificial circulation. Quality and purity of protamine may be the causes of side effects. Negative effect of high doses of protamine on hemostasis system is demonstrated. Thrombocyte dysfunction is the main cause of intensive postoperative bleeding after administration of protamine high doses.

[A method for calculating the additional quantity of protamine sulfate during cardiosurgical operations].

The paper describes a method for calculating the additional dose of protamine sulfate solution during incomplete heparin neutralization after cardiac surgery under extracorporeal circulation, by estimating the anti-Xa-activity of venous blood plasma. The method may be an alternative to the use of devices to measure the blood concentration of free heparin, such as a "Hepcon" apparatus.

[The specific features of renal dysfunction in cardiosurgical patients].

Subclinically insignificant glomerular filtration disturbances were found during operations under extracorporeal circulation. After termination of perfusion, dysfunction of the proximal portion of renal tubules was recorded in all patients. This may be associated with that the proximal tubules were more susceptible to ischemia. Further impairments of the distal portions of renal tubules suggest the persistence of ischemic lesions of the tubular apparatus.

[Haemorheological impairments following aortic surgery and methods of correction thereof].

The article deals with the findings concerning alterations in rheological properties of the blood in patients who endured aortic surgery with and without artificial circulation. Also shown herein is the contribution of the plasmatic and erythrocytic components to the development of haemorheological disorders in the postoperative period. To this was added the assessment of the role plasmapheresis plays in correction of impaired blood rheological properties, depending upon the terms of its carrying out and the type of a surgical intervention performed.

[Influence of extracorporeal circuits surface on hemostasis system during off-pump surgeries].

It is demonstrated that special surface of extracorporeal circuit promotes reduction of artificial circulation negative influence on hemostasis system. During artificial circulation coating "duraflo" gradually loses its protective characteristics due to washout of heparin molecules from the surface of extracorporeal circuit, whereas chemical link between heparin and protein in "safe-line" coating is more stable. The results of the study demonstrate no advantages of heparin coating of extracorporeal circuits over protein one. Finally, all the advantages of extracorporeal circuits with "safe-line" coating lead to a decrease of postoperative blood loss.

[Comparison of two schemes of administering the Russian protamine sulfate after extracorporeal circulation in cardiosurgical patients].

The paper presents data of a study comparing two schemes (Scheme 1: a heparin/protamine ratio of 1:2; Scheme 2: a heparin/protamine ratio of 1:3) for administering protamine sulfate to neutralize heparin in patients after extracorporeal circulation. A larger dose of protamine sulfate is shown to induce significant thrombocytic dysfunction, resulting in increased postoperative hemorrhage. To minimize protamine sulfate doses required for neutralization of the anticoagulant effect of heparin is a way of preventing these complications.

[Changes in cerebral circulation in patients with coronary heart disease during myocardial revascularizing operations under combined xenon anesthesia].

Twenty-five patients with coronary heart disease were examined in the preperfusion stage of myocardial revascularing operations under extracorporeal circulation. All the patients received combined anesthesia with xenon (Xe) as minimum flow anesthesia with flow of gases: oxygen, 0.4 l/min; Xe, 0.9 to 0.4 l/min. Cerebral circulation was investigated by transcranial Doppler study. The following parameters of the circulation: maximum systolic and diastolic blood flow velocities and pulsatile index were bilaterally estimated, by insonating the middle cerebral artery (MCA). When the concentration of Xe was as high as 50-60%, systolic and diastolic blood flow velocities along the MCA increase and the pulsatile index decreased. Opposite results were obtained 8 minutes after Xe feed was stopped. The findings provide evidence that Xe increases cerebral circulation and has a significant hypnotic effect. The increased systolic and diastolic blood flow velocities with the decreased peripheral resistance index in the MCA suggest that Xe diminishes peripheral vascular resistance in the pial arteries of the brain.

[Alterations in certain indices of the haemostasis system following aortic surgery].

MATERIAL AND METHODS: A total of 24 patients were examined after surgery on the thoracic or abdominal aorta. Depending on the level of the aortic clamping at the main stage of the operation, the patients were subdivided into three groups: Group One was composed of 7 patients with aortic coarctation in whom the level of artery clamping was located just below the subclavian artery, Group Two comprised 7 patients with an aneurysm of the infrarenal aortic portion, with the clamp applied immediately underneath the renal arteries, and Group Three consisted of 10 patients with type IV thoracoabdominal aortic aneurysm according to Crawford's classification, with the artery being clamped above the diaphragm. The studies were carried out at the following stages: before and at the end of surgery, then 6 hours thereafter, and at 24 hours postoperatively. RESULTS: The alterations in the indices of plasma-thrombocytic haemostasis at all the stages were insignificant and did not differ reliably between the groups. In Group One patients, the time of XHa-kallikrein-dependent fibrinolysis (XIIaKDF) at the end of the operation was found to be within the range of the normal values(657.5+/-92.3 s) and had no statistically reliable differences from the baseline value (612.0+/-63.7 s). After 6 hours and on day 1 after the operation, we observed inconsiderable inhibition of the fibrinolytic activity (903.0+/-142.3 and 848.9+/-149.5 s, respectively). In Group Two patients at the end of the operation, we registered a statistically reliable, as compared with the baseline value, shortening of the time of XIIaKDF (from 990.0 +/-81.0 to 510.0 +/- 103.6 s, p<0.05). However, the subsequent stages of the follow-up revealed a dramatic decrease in the fibrinolytic activity (to1.388.0+/-183.1 s). Group Three patients demonstrated a considerable activation of fibrinolysis at the end of the operation (348.2 +/-48.5 s), which was noted to remain unchanged during the first 24 postoperative hours, with the alterations in the D-dimer's concentration in patients of all groups at the stages of observation being of a unidirectional pattern, i. e. increasing maximally after 6 hours to be then decreasing on the first 24 hours after the operation. CONCLUSION: To prevent postoperative haemorrhage associated with hyperfibrinolysis in aortic operations, it is necessary to administer antifibrinolytic drugs with due regard for the level of aortic clamping.

[Comparative evaluation of clinical use of cardioplegic solutions custodiol and konsol in the correction of cardiac valvular diseases].

The efficiency of myocardial protection with cold crystalloid cardioplegia (CC) during operations on the heart under total ischemia and extracorporeal circulation was studied. Two hundred and fifty patients who underwent prosthetic or plastic repair of the aortic and mitral valves or plastic repair of the tricuspid valve were examined. Group 1 comprised 218 patients in whom the myocardium was protected with Konsol solution ("Biofarm "research-and-production enterprise, Russia); Group 2 included 32 patients in whom Custodiol solution ("Dr Franz Kohler Chemia GMBH", Germany). The volume of the Konsol solution required for CC was 400-2000 ml, with the duration of myocardial ischemia (MI) being 75 +/- 33 min; that of the Custodiol was 2000-4000 ml, with the duration of MI being 80 +/- 22 min. The used algorithm of administration of the solutions provided a persistent cardioplegic effect in both groups. After aortic declamping, there was a spontaneous recovery of cardiac performance in 84 and 40% in Groups 1 and 2, respectively. In the reperfusion period (RP), no significant differences were found in the basic hemodynamic parameters (heart rate, blood pressure, and central venous pressure) in both groups. After defect correction, cardiac output equally increased in both groups. The groups did not differ in the rate of inotropic support either. In RP, transient cardiac rhythm and conduction disturbances occurred in 19 and 28% in Groups 1 and 2, respectively.

The causes of early disorders of cerebral circulation in patients undergoing carotid endarterectomy.

AIM: to examine hemostasis in patients undergoing carotid endarterectomy as dependent on the course of the short-term postoperative period. MATERIALS AND METHODS: altogether 36 patients who had undergone unilateral carotid endarterectomy (CEAE) were examined. Intraoperatively, all the patients received unfractionated heparin (UFH) in a dose of 80 - 100 IU/kg bw. As dependent on the course of the short-term postoperative period the patients were distributed into two groups: group 1 included 12 patients who developed disorders of cerebral circulation (DCC) within the first hours after operation, group 2 included 24 persons with no complications. Plasma-platelet hemostasis, the system of natural anticoagulants and fibrinolysis were examined before, at the end, 6 hours and on the first day after CEAE. RESULTS: prior to operation all the patients had no significant change in the hemostatic system. Toward the end of operation groups 1 and 2 did not differ in the basic parameters of the hemostatic system. Group showed a remarkable platelet hyperaggregation. Six hours after operation group 1 demonstrated significantly lower values of ACT, BCT, MHO, an appreciably higher value of APTT and pronounced inhibition of fibrinolytic activity associated with platelet hyperaggregation. On the first postoperative day group 1 retained a significantly lower value of BCT, showed a significant lowering of APTT as compared to the previous observation stages and comparatively to group 2, demonstrated a significantly lower activity of AT III and fibrinolysis. At this stage ADO-induced platelet aggregation in group 1 was appreciably higher than in group 2. Platelet hyperaggregation in group 1 patients appeared a first manifestation of consumption coagulopathy. The significantly higher value of APTT mirrored a compensatory output of endogenous heparin. On the first postoperative day group 1 demonstrated a remarkable consumption of endogenous heparin, noticeably lower activity of AT III, material XIIaKDF inhibition, and retained pronounced platelet hyperaggregation. CONCLUSION: the intensity and extent of the atherosclerotic process in the cerebral vessels together with platelet hyperaggregation lead to the rise of the thrombogenic potential and increase the risk of thrombogenic complications in the immediate hours following operation. Antiaggregation and anticoagulation therapy should be instituted in such patients in the preoperative period and resumed directly after operation.