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The hemodynamic parameters (BP, HR, YO) were studied in 50 patients aged 9 to 77, ASA I-IV, subjected to endoscopic surgery on the tracheobronchial tree. Use of ketamine in these patients in schemes of anesthesia before induction with diprivan had a favorable effect on the hemodynamic stability and did not influence the recovery. Moreover, schemes including ketamine are advisable when prolonged artificial circulation is needed by surgical indications (dilatation or stenosis).

Halothane impact on cerebral blood flow, brain metabolism and its protective effect in ischemia have been assessed in 30 patients operated on for the occlusion of brachiocephalic arteries. The data obtained indicate that additional use of halothane in N2O:O2 anesthesia during reconstructive surgery on brachiocephalic arteries makes it possible to enhance collateral blood flow, increase retrograde pressure, and decrease O2 consumption by the brain, without considerable changes in systemic hemodynamics. In addition, the studies have shown that halothane decreases lipid peroxidation processes.

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 absence of direct studies of pulmonary circulation in the majority of papers, as well as the effect of various techniques of controlled lung ventilation on pulmonary microcirculation and the right heart made us start the present investigation. Ultrasound sensors have been implanted on the pulmonary artery cone and aortic arch in 30 healthy cats during thoracotomy under pentobarbital anesthesia (30-40 mg/kg). Blood flow through the pulmonary artery and aorta, as well as their interrelation have been studied using MX-01. BP and PAP were registered using an invasive technique. Computer assessment of other hemodynamic parameters used cardiac output values into the pulmonary artery and into the aorta for the calculation of pulmonary circulation parameters and systemic circulation parameters, respectively. Pulmonary microcirculation has been studied by an original technique of intravital biomicroscopy of the lungs, with the image recorded on the video camera. To determine the index of capillary perfusion a semiautomatic device for image analysis ("Leitz" and "Olivetti") was used. It has been established that in high-frequency jet ventilation there is a redistribution of circulating blood towards systemic circulation. Right ventricular work decreases by 53.6% (p < 0.05) due to a drop in vascular resistance in pulmonary circulation (p < 0.05) and pulmonary artery pressure (p < 0.05), while left ventricular work decreases by 14.8% (p < 0.05). Thus, there is a predominant load reduction in the right heart compartments. In conventional controlled lung ventilation microcirculatory bed of the lungs is subjected to characteristic deformation, i. e. distension enhancing vascular resistance and thus leading to additional load on the right heart compartments.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Application of a shunt is not the principal factor preventing brain blood flow disorders in reconstructive surgery on the carotid arteries in conditions of general anesthesia with anesthetics of an antihypoxic action, reducing oxygen consumption by the brain, combined with adequate compensation of the circulating blood volume, moderate hemodilution, elevation of the systemic arterial pressure and heparin. The authors claim that even in patients with bilateral stenosis of the carotid arteries or with occlusion of one of these arteries surgery may be carried out without shunts or craniocerebral hypothermia. Still, they do not deny a bypass application, particularly by the surgeons who always use it, or in cases with a drastic inhibition of the brain electrical activity, evidenced by EEG, which they consider a sufficiently reliable indicator of the brain blood flow adequacy.

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.

The authors analyse experience in the first eight operations for orthotopic transplantation of the heart. Six patients were discharged from the clinic with good immediate results. Comparison of their own data with summarized results gained in other countries allowed the authors to define some specific problems which are of practical interest for clinics embarking on the clinical realization of the problem of heart transplantation.

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 effects of glycerol trinitrate (GTN), sodium nitroprusside and isoket on central hemodynamics, myocardial contractility and myocardial function have been compared. 65 patients with ischemic heart disease have been examined. All the patients were divided into 3 groups depending on the drug studied. GTN was administered sublingually at a dose of 0.5 mg, while sodium nitroprusside and isoket were infused at doses of 1.5 micrograms (kg min) and 400 micrograms/min, respectively. It has been shown that GTN and isoket effects on central hemodynamics were mainly mediated by their venodilating action and preload reduction, thus promoting to the improvement of the myocardial function. Hemodynamic effects of sodium nitroprusside on the cardiovascular system are mediated by its dilating action on the arterial bed and afterload reduction.