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The paper deals with the development of a diagnostic and therapeutic algorithm of intraoperative heart failure during cardiosurgical operations on the basis of evaluation of systolic and diastolic functions of the left and right ventricles. The study included 101 patients with low cardiac output in the postperfusion period. All the patients suffered from coronary heart disease and they underwent myocardial revascularizing operations under extracorporeal circulation. In all the patients, in addition to traditional hemodynamic parameters (heart rate, blood pressure, central venous pressure), the functional status of the left and right ventricles was evaluated by transesophageal Doppler echocardiography (TED echoCG) and the thermodilution technique using a Swan-Ganz catheter having a prompt thermistor. Evaluating the diastolic and diastolic functions of the right and left ventricles makes it possible to identify 2 types of left and right ventricular failure: 1) that due to systolic dysfunction and 2) that due to concomitance of systolic and diastolic dysfunctions. Dobutrex (5-7.5 microg/kg/min) should be used in right ventricular systolic dysfunction. Amrinone (5-10 microg/kg/min) should be given to patients with concomitance of systolic and diastolic dysfunction; in this situation, a combination of dobutrex and nitroglycerin (100-150 ng/kg/min) may be used. The drugs of choice in impaired left ventricular systolic function are epinephrine (30-100 ng/kg/min), dopamine (5-10 microg/kg/min), or dobutrex (5-7.5 microg/kg/min). Their combination with sodium nitroprusside can enhance the efficiency of therapy. In patients with left ventricular failure caused by systolic and diastolic dysfunction, epinephrine, dopamine, or dobutrex may be combined with amrinone (5-10 microg/kg/min) or nitroglycerin (100-150 ng/kg/min).

The automated workplace (AWP) of anesthesiologist developed by the early 1990s provided data collection and processing, viewing of all monitors, and printing of anesthesiological chart (AC). AWP is a subject of continuous modification and adaptation to variable conditions. Computer monitoring including various measuring devises equipped with series interface RS-232 was implemented in Russian Research Center for Surgery. Rapid progress in computer network technologies made it necessary to adapt AWP to operation in computer networks. Since 1999 the computer network has been connected to the Internet. The use of computer technologies, including Internet, provides remote access to AC, thereby providing conditions for remote monitoring. AWP of anesthesiologist can be regarded as an automated control system of the patient state operated by anesthesiologist. Specific features of data processing in AWP are described. The AWP system is planed to be multiprocessor with distributed data flow. The suggested structure of computer network system for surgery rooms meeting the requirements of WWW-technology connected to the Internet is a promising approach to remote monitoring in medicine.

The electromyographic and hemodynamic profile and side effects of the new nondepolarizing myorelaxants Mivacurium chloride (Mivacron), Cisathracurium besilate (Nimbex), Rocuronium bromide (Esmerone) were studied in 117 adult patients. All the test myorelaxants as bolus or infusion in a dose of 3.ED95 were found to be effective in creating adequate conditions for tracheal intubation and neuromuscular block (NMB) maintenance during operations on the coronary arteries and cardiac vales under extracorporeal circulation. In terms of the onset rate of NMB, Esmerone is the drug of choice for tracheal intubation. Esmerone and Nimbex in a dose of 3.ED95 did not produce a noticeable hemodynamic effect. The former was found to have a slight vagolytic effect. When rapidly injected as bolus, Mivacron caused a significant decrease in blood pressure and heart rate by 10-12%. Based on a comprehensive study, the authors have scientifically substantiated principles in the choice of nondepolarizing myorelaxants in cardiac surgical patients in relation to the baseline hemodynamic values, the stage of an operation, and the duration of artificial pulmonary ventilation.

Hemodynamics, gas exchange, velocity of psychomotor recovery, pain intensity during and after laparoscopic cholecystectomy were studied in patients anesthetized (total intravenous anesthesia) by two methods: 1) remifentanyl and propofol, forced ventilation of the lungs, and myoplegia (n = 21, ASA I-III) and 2) fentanyl and propofol, forced ventilation of the lungs, and myoplegia (n = 18, ASA I-III). Total intravenous anesthesia based on remifentanyl was characterized by stability of hemodynamic and gas exchange parameters at all stages of the intervention. This method ensured a smooth and rapid course of resuscitation, characterized by absence of signs of central respiration depression, predictable normalization of psychomotor status, and low incidence of factors provoking postoperative nausea and vomiting, on condition of their prevention. Further studies of remifentanyl are needed in interventions of different degree of traumatism and within the framework of different protocols of postoperative analgesia.

57 ischemic heart disease (IHD) patients entered the study of right and left heart function at different stages of anesthesia and operation to reveal possible reasons of myocardial dysfunction and to propose effective prevention of this dysfunction. All the patients were operated on under multicomponent balanced anesthesia (relanium, fentanyl, arduan, nitric oxide with oxygen 1:1). Left ventricular function was assessed at Doppler echocardiography, right ventricular function--at catheterization of the lung artery with a Swan-Ganz catheter with low time constant. Hemodynamic monitoring was made with a domestic MX-04 monitor. It was found that in the preperfusion period diastolic function of the right and left ventricles is impaired much more than the systolic one. The conditions of anesthesia and operation affect right ventricular function more than the left one. Diastolic and systolic right ventricular dysfunctions were observed at all stages and three stages of the operation, respectively. Diastolic and systolic left ventricular dysfunction was observed at four and one stages, respectively. Basic causes of the above systolic and diastolic disorders in the preperfusion period may be tachycardia, arterial hypertension, reduction of the preloading and increased postloading (for the right ventricle) in artificial lung ventilation.

Two groups of coronary patients subjected to revascularization of the myocardium were examined in order to detect the negative hemodynamic effects of protamine sulfate (PS) and the possibility of their correction by simultaneous infusion of adrenaline microdoses. In group 1 (27 pts.) heparin was neutralized by infusion of PS alone (6 mg/kg) and in group 2 (27 pts.) by simultaneous infusion of PS and adrenaline (15 ng/kg/min). The functions of the right and left ventricles were evaluated by catheterization of the pulmonary artery by a Swan-Ganz catheter and transesophageal Doppler echocardiography. These methods provided volume and velocity characteristics of the right and left compartments of the heart. PS deteriorated the systolic function of the right ventricle, particularly in patients with initial dysfunction of the right heart. Infusion of adrenaline simultaneously with PS leveled its negative effects, thus preventing myocardial dysfunction.

Total intravenous propofol anesthesia with target control (TCI) infusion was used in 61 surgical patients (43 women, 18 men, ASAI-II). Propofol concentration in the central compartment at awakening was in high correlation with the effective concentration (Ce) at the moment of falling asleep (r = 0.64). A model investigation demonstrated the advantages of longer induction for minimization of the hemodynamic disorders. Propofol TCI in a dose of 2 micrograms/ml led to an increase in the EEG spectral potency in the 1-12 Hz range, appearance of biomodality, and a decrease in the right-side frequency. The studies helped determine the policy of intravenous propofol TCI anesthesia using the Ce values at the moment when the patient lost consciousness and the right-side frequency of EEG spectrum.

Clinical trials of a new anesthetic Recofol were carried out. This analog of well-known drug diprivan is characterized by a predominantly hypnotic effect. The effect of recofol on hemodynamics, gas exchange, and EEG was studied in 30 clinical trials during anesthesia for bronchoscopic manipulations and operations on the abdominal and thoracic organs, microsurgery, and during peripheral vessel repair. The results indicate that recofol is virtually identical to diprivan (propofol). Clinical course of induction and anesthesia, hemodynamic reactions and effect on the respiratory system of patients were virtually the same. Recofol was well tolerated, its allergenic activity was relatively low, it was rapidly metabolized, there were virtually no side effects. Positive results of recofol trials carried out by Leiras Oy firm recommend the drug for wide use in anesthesiology.

Perioperative echocardiography and right ventricular volumic monitoring were used for more essential evaluation of different hypnotics in cardiosurgical patients. Our comparative study has shown that all the examined hypnotics induced no changes in systolic function of the left ventricle. Midazolam and propofol exerted minor depressive influence only on diastolic left ventricular function without significant fall of cardiac output. Etomidate moderately worsened diastolic and systolic right ventricular function with cardiac output decrease. The combined use of diazepam and ketamine provided excellent hemodynamic stability without negative effects on systolic and diastolic heart function.

Thirty patients aged 23 to 65 years with ASA class III operated on the heart under total intravenous anesthesia were examined after the Good Clinical Practice protocol. Mivacurium in bolus dose of 0.2 mg/kg was injected for intubation of the trachea; neuromuscular blocking (NMB) was maintained by a repeated injection of the drug in a dose of 0.15 mg/kg, after which it was infused at a rate of 1 to 10 micrograms/kg/min. Accelerometric control of neuromuscular conduction was carried out by the Organon (Belgium) TOF-Guard device. Central and peripheral hemodynamics was monitored. Side effects of the drug were recorded. Bolus injection of mivacurium in a dose of 0.2 mg/kg caused T1 suppression (90%) after 2.6 +/- 0.7 min. Maximal (97.7 +/- 4.5%) suppression was observed after 4.17 +/- 2.5 min. The conditions of intubation of the trachea after 3.9 +/- 1.8 min in the presence of 78 to 100% T1 suppression (97.7 +/- 4.5%) were considered excellent or good in 96.6% of cases. Clinically and neurophysiologically sufficient muscle relaxation after the first injection of the drug persisted for 27.7 +/- 7.3 min. Minimal rate of infusion for maintaining the NMB at 95 +/- 4% level of T1 suppression was 6.3 +/- 1.7 micrograms/kg/min. Bolus injection of mivacurium in a dose of 0.2 mg/kg for 60 sec involved a 1-3-min drop of the mean arterial pressure by 10.5% and a 10.3% decrease of heart rate. Repeated bolus injection of the drug in a dose of 0.15 mg/kg and its infusion did not change the peripheral and central hemodynamics. The most typical side effect of the drug in a dose of 0.2 mg/kg is short-term reversible reddening of the skin of the face and neck, observed in 20% of patients. The results permit us to consider mivacurium as an effective, safe, and controllable agent, which can be used in cardiosurgical patients.

Dilazin in a dose of 0.2 mg/kg/min (n = 20) and 0.4 mg/kg/min (n = 20) was used to normalize arterial blood pressure during and after surgery. Intravenous infusion of the drug decreased the arterial pressure to baseline values within 2-3 min by reducing the elevated systemic vascular resistance. Dilazin did not affect the heart rate, mean pulmonary capillary wedge pressure, or central venous pressure. The drug brought about a marked increase of cardiac output and cardiac index. Prompt effect and easy control, when dilazin is infused in a dose of 0.2 to 0.4 mg/kg/min, recommend it as an alternative antihypertensive agent to be used during various procedures.

Bioelectric activity and metabolism of the brain were studied during surgery on the aorta with deep hypothermal arrest of circulation. The study included 9 patients (7 men and 2 women) aged 13 to 66 years. The mean duration of circulation arrest under deep hypothermia was 48.6 (from 19 to 77) min. Before circulation arrest the patients were cooled to nasopharyngeal temperature of 13.5 +/- 0.5 degrees C and rectal temperature of 15 +/- 0.6 degrees C. Deep hypothermia involved the disappearance of bioelectrical activity and decrease of the spectral power of all EEG frequency bands. The most notable changes in the hemoglobin saturation of the blood in the internal jugular vein bulb (SibO2) were observed during artificial circulation and hypothermal arrest of circulation. Cooling of patients led to a gradual increase of its values. Before deep hypothermal arrest of circulation SjbO2 was as high as 98.4 +/- 0.4%. Over the period of circulation arrest its level dropped to 85.7 +/- 4.8%. Subsequent warming led to its further decrease, and by the end of artificial circulation it was as initially. The content of carbon dioxide in the blood flowing from the brain increased from 17.0 +/- 0.9 to 31.7 +/- 4.7 mm Hg over the period of heart arrest, which may be indicative of the continuing metabolic processes in the brain under conditions of deep hypothermia and justifies the additional drug protection and local hypothermia of the head.

The authors assess the potentialities of a new method; fiber optic oxyhemometry of the blood flowing from the brain (at the level of the upper bulb of the internal jugular vein) during heart surgery. They demonstrate a sufficiently high accuracy of the method. Using it during cardiosurgical operations under artificial circulation, they found it highly informative and sensitive to even suddenly emerging and short-term changes in the ratio of oxygen delivery/consumption by the brain.

Metabolism of the brain was studied in 82 cardiosurgical patients operated on under conditions of hypothermal and normothermal artificial circulation (AC). The principal differences in the pattern of changes of cerebral metabolism were observed at the stage of heart connection to the bloodflow, corresponding to the period of warming during hypothermal AC. The detected reduction of oxygen extraction and arteriovenous glucose difference in the normothermal group may be a result of cerebral bloodflow shunting, and more pronounced stimulation of free-radical processes be indicative of the possible injury to cerebral structures in the absence of protective effect of hypothermia.

Monitoring of brain metabolism is used to assess the adequacy of brain cooling during operations performed under conditions of deep hypothermal perfusion and temporary arrest of circulation. Such monitoring consists in continuous recording of hemoglobin saturation of the blood flowing from the brain by fiberoptic oximetry and testing of blood samples collected from the upper internal jugular bulb. A patient is described, who had been operated with good results under conditions of deep hypothermal perfusion and 30-min arrest of circulation.

Methods of catheterization of the upper internal jugular bulb are described. The authors recommend to identify it basing on the difference between gaseous composition of blood samples collected simultaneously at two levels. The informative value of catheterization of the upper internal jugular bulb for assessment of brain metabolism is demonstrated.

Methods of myocardial protection from ischemic and reperfusion injuries in various operations on the open heart were compared. The study demonstrated the advantages of combined antegrade-retrograde delivery of cardioplegic solution during ischemia in aortocoronary shunting and correction of valvular defects. The method of myocardial protection from reperfusion injury by perfusing the heart with blood solution of a special composition before removing the clamp from the aorta (controlled reperfusion) proved to be effective, which was confirmed by clinical and biochemical data presented in this paper. Hence, our findings confirmed that the optimal protection of the myocardium can be attained by combined cold crystalloid cardioplegia together with controlled reperfusion of the myocardium.

Creation of computer monitoring systems (CMS) for operating rooms is one of the most important spheres of personal computer employment in anesthesiology. The authors developed a PC RS/AT-based CMS and effectively used it for more than 2 years. This system permits comprehensive monitoring in cardiosurgical operations by real time processing the values of arterial and central venous pressure, pressure in the pulmonary artery, bioelectrical activity of the brain, and two temperature values. Use of this CMS helped appreciably improve patients' safety during surgery. The possibility to assess brain function by computer monitoring the EEF simultaneously with central hemodynamics and body temperature permit the anesthesiologist to objectively assess the depth of anesthesia and to diagnose cerebral hypoxia. Automated anesthesiological chart issued by the CMS after surgery reliably reflects the patient's status and the measures taken by the anesthesiologist.

The effects of nitroglycerin on central hemodynamics and direct myocardial contractility were directly studied in 32 patients with functional class III-IV heart failure during aortocoronary bypass surgery. When nitroglycerin was used, hemodynamic parameters changed in two stages: 1) systemic blood pressure initially slightly increased; 2) decreases in this and other central hemodynamic parameters occurred. The dynamics of myocardial function was determined by its baseline state, dyskinetic intensity, i.e. its contractility. In patients with preserved myocardial function, nitroglycerin failed to cause its substantial dysfunction. At the same time its contractility and central hemodynamic parameters might considerably deteriorate in patients with moderate dyskinesia and furthermore with severe myocardial dysfunction.

A new analgesic fenaridine which was used as a component of balanced anesthesia in 160 operations of aortocoronary bypass has been studied. It has been shown that fenaridine is a potent analgesic, exceeding fentanyl in the duration of action and in its analgetic effect. Fenaridine has a pronounced sedative effect and like other analgesics causes a dose-dependent depression of respiration. The drug has a vasodilating activity, causing both venous and arterial dilatation. This leads to a decrease in CVP by 25-30%, on the one hand, and to a drop in BP by 20%, on the other hand. Fenaridine decreases Vmax and dP/dt by 18 and 20%, respectively, with a parallel decline in HR by 13% from the baseline. A marked vasodilating effect and potentiation of the action of diazepam and other benzodiazepines in prompt injection of both drugs or when the maximum dose of fenaridine is used may lead to the onset of hypotension, and thus the drug should be used with care in critical patients with hypovolemia. The use of lower fenaridine doses (not exceeding 0.001 mg/kg) and slow injection (up to 11-13 min), as well as its combination with ketamine at a dose of 1.5 mg/kg makes it possible to avoid these unfavourable adverse events and to ensure smooth induction even in critically ill patients.

The effect of a novel ultrashort acting beta-adrenoblocker esmolol on systemic and pulmonary hemodynamics has been studied intraoperatively in 81 cardiosurgical patients. All the patients were operated under ataralgesia. Esmolol is an effective controlled agent for the treatment and prevention of supraventricular tachycardia and hyperdynamic reaction developing in cardiothoracic patients during anesthesia and surgery. Bolus injection of 100 mg esmolol exerts a negative chronotropic effect with maximum heart rate decrease by 23.3% by minute 5 and a gradual attenuation of the effect by minute 20. A parallel drop in the cardiac output by 18.5% is caused predominantly by a decrease in the heart rate and accounts for BP reduction. The above esmolol dose does not have a considerable effect on pulmonary hemodynamics and does not enhance intrapulmonary venous shunting.

The pulsed oximeters "Satlite" and Satlite Trans" (Datex, Finland), "Biox-3700' (Ohmeda, USA) "OXI" (Radiometer, Denmark), "Danamap-Oxytrak" (Critikon, Johnson & Johnson, USA) are essential and highly precise devices for controlling vital functions of the body during anesthesiologic techniques. The delay time of a response of the pulsed oximeters "Satlite Trans" and "Box-3700" in providing the values of the saturation of arterial blood hemoglobin with oxygen is 40 sec. The pulsed oximeter-personal computer system opens up new possibilities of increasing the quality of monitoring and safety of bronchoscopic studies and operations and allows a protocol of the intervention to be developed.

The interrelationship of the cardiac index (CI) and carbon dioxide concentration measured at the end of respiration (CO2ER) was studied in 258 patients, aged from 5 to 71 years, during operations on the open heart. Statistical analysis of the stage of revision of the left ventricular posterior wall showed that CO2ER decreases from 29.9 +/- 0.7 mm Hg to 24.9 +/- 1.4 mm Hg in parallel with reduction of CI from 2.81 +/- 0.19 l/min/m2 to 1.62 +/- 0.13 l/min/m2. At the end of this manipulation the CI and CO2ER were restored to the initial level. Marked parallel dynamics of CO and CO2ER was revealed in continuous appraisal of the cardiac output (CO), determined by the method of catheter flow measurement, at the stage of parallel circulation and blood pumping from the extracorporeal circulation apparatus before CO2ER stabilization. The correlation coefficient of these parameters varied in this stage in various patients from +0.73 to +0.96. Analysis of the mass of data (n = 161) collected in 14 patients showed that the CI--CO2ER relation was exponential in character and could be expressed by the equation CI (l/min/m2) = e (-0.99 + 0.065 x CO2ER); standard determination error +/- 0.42 l/min/m2. Analysis of the "CO2ER-venous pressure" relation in these 14 patients showed it to be similar to the "cardiac index-venous pressure" relation. The coefficients of correlation between CVD and CO2ER at this stage ranged in various patients from +0.74 to +0.96 and those between VP and CI from +0.58 to +0.97. Transition of the relations to the plateau occurred at equal CVP values.

New criteria of the arterial blood oxygen transport function suggested by O. Siggaard-Andersen et al. are reviewed. The examples from clinical practice show the possibility to evaluate the capacity of the arterial blood to transport O2 during general anesthesia and intensive care.

Monitor-computer study of changes in the ventilatory parameters, hemodynamics, gas exchange has shown that assisted circulation in patients operated on for acquired heart valve defects causes in the postperfusion period a 2-fold increase in intrapulmonary venous admixture (Qs/Qt), which accompanied an increase in alveolar-arterial difference (pO2) and a fall in arterial blood pO2. An increase in Qs/Qt upon assisted circulation is associated with a decrease in ventilation/perfusion pulmonary ratio and possible deterioration of diffuse processes due to hemodilution-induced water balance disturbances. Controlled lung ventilation with positive end respiratory pressure (5-8 cm H2O) partially decreases intrapulmonary shunting and improves arterial blood oxygenation. Positive effect, i. e. improved oxygenating lung capacity and decreased intrapulmonary shunting is achieved with water balance normalization due to early administration of diuretics upon assisted circulation.

A retrospective analysis of arterial blood oxygenation during open-heart surgery in 463 patients revealed pulmonary oxygenation disorders in 23% prior to perfusion and in 49% in the post-perfusion period. The basic mechanism underlying the fall in arterial blood oxygenation is the increasing venous admixture in the lungs. A growth in the venous admixture in the post-perfusion period is brought about by a decreased total ventilation/perfusion ratio, increased alveolar shunting, and impaired diffusion. It was found, that the assisted ventilation regimen at +5+8 cm H2O in the post-perfusion period caused a 30% reduction in the venous admixture and improved the blood oxygenation. Additional use of diuretics to diminish the intrapulmonary water causes a 59% reduction in the venous admixture. A prophylactic pre-perfusion administration of corticosteroids, vitamin E, and protease inhibitors maintains the oxygenating function of the lungs, which is manifested in a higher blood oxygenation in these patients after assisted circulation compared to the controls.

The authors studied the effect of isoket on the central hemodynamics and myocardial contractility as well as on the conditions of myocardial functioning in 38 patients aged 28-53 years and suffering from coronary heart disease. The infusion of 2 mg of isoket at a rate of 400 micrograms/min was followed by a decrease in the arterial pressure with the maximum drop seen on the seventh minute (by 26% from the baseline value), a reduction in the end-diastolic pressure by 50%, and a lengthening of the preejection period without any significant changes in either the cardiac output or the total peripheral resistance. Taken as a whole these changes justify the conclusion that the influence of dinitrate isosorbite (isoket) on the central hemodynamics is largely due to its venodilating action leading to a reduction of the pre-load which in turn improves myocardial functioning.