Effect of systemic vasodilators on internal mammary flow during coronary bypass grafting.

BACKGROUND: The effect of vasodilators on acute flow in the internal mammary (IMA) is unclear. Topical vasodilators show no effect on acute flow when the distal segment of the IMA is resected. The purpose of this study was to evaluate the effect of systemic vasodilators when this segment is resected. METHODS: We studied 60 patients with proximal anterior descending coronary artery lesions in whom the left IMA was harvested for grafting to the left anterior descending coronary artery. The patients were divided into six groups (n = 10), based on which of the following agents were studied: normal saline solution, nitroglycerin, nitroprusside, dobutamine, dopexamine, and amrinone. After harvesting, the IMA was trimmed as proximally as possible (and at least 3 cm proximal to the bifurcation), and free flow was measured before any pharmacologic intervention (flow 1). Systemic infusion of one of the six agents commenced. A mean of 17 +/- 3.4 minutes after infusion began, with a comparable cardiac index, a second measurement of IMA flow was taken (flow 2). Hemodynamic measurements for each flow, including blood pressure, heart rate, and cardiac output, were taken. RESULTS: A significant increase in IMA flow was noted for those patients receiving nitroglycerin (93.5 versus 106.8 mL/min; p = 0.025), and a significant decrease in flow was noted for those receiving nitroprusside (91.0 versus 78.2 mL/min; p = 0.042). The effects remained significant when corrected for cardiac index and compared with the normal saline solution group. No other systemic agents tested significantly affected the IMA flow (dobutamine, 83.8 versus 85.0 mL/min; dopexamine, 101.8 versus 91.4 mL/min; amrinone, 75.4 versus 79 mL/min; normal saline solution, 85.8 versus 84.6 mL/min). CONCLUSIONS: Resection of the distal segment of the IMA and the use of intravenous nitroglycerin optimizes the flow in IMA grafts.

Non-invasive measurement of cardiac output during coronary artery bypass grafting.

OBJECTIVE: A new device, using whole body bioresistance measurements and a new equation for calculating stroke volume has been developed. Using this equation, an attempt was made to correlate whole body bioresistance cardiac output with thermodilution cardiac output in patients undergoing coronary artery bypass grafting. METHODS: Thirty-one adults undergoing elective coronary artery bypass grafting were studied prospectively. Simultaneous paired cardiac output measurements by whole body bioresistance and thermodilution were made at five time points during coronary artery bypass grafting: in anesthetized patients before incision (T1), after sternotomy (T2), after opening the pericardium (T3), ten min post bypass (T4), and in the intensive care unit (T5). The patients had a mean of three thermodilution cardiac outputs compared with a mean of three bioimpedance measurements at each time point. The bias and precision between the methods were calculated. RESULTS: There was good correlation between bioresistance cardiac output (nCO) and thermodilution cardiac output (ThCO) measurements in both groups for all recorded times. The patients' mean ThCO and nCO, as well as bias and precision between methods were calculated. Mean ThCO ranged between 4.14 and 5.06 l/min; mean nCO ranged between 4.12 and 4.97 l/ min. Bias calculations ranged between -0.072 and 0.104 l/min. Precision (2 SD) calculations ranged between 0.873 and 1.228 l/min for 95% confidence intervals. Pearson's correlation ranged from 0.919 to 0.938. CONCLUSIONS: Cardiac output measured with the new device correlates well with the thermodilution measurements of cardiac output during and immediately following coronary artery bypass grafting. The overall agreement between the two methods was good. The new device is an accurate non-invasive method of measuring cardiac output during coronary artery bypass grafting.

[Immunoepizootological study of ovine toxoplasmosis]. / Imunoepizootologická studie ovcí toxoplazmózy

The authors examined for toxoplasmosis (by means of an indirect hemagglutination reaction) 698 sheep kept in different places in Bulgaria. Out of this total number, 217 (= 31.1%) responded positively to the tests. In sheep delivering stillborn foetuses the positive response was much more frequent (43.3%) than in sheep with normal parturitions (21.0%). Sheep from montane regions showed a significantly higher positivity (40.3%) than sheep from lowland regions (18.3%). Three cystogenic strains of Toxoplasma gondii were isolated from six stillborn lambs. Out of the 493 sheep examined in Czechoslovakia, 33.3% gave a positive response in an indirect hemagglutination reaction, 29.7% responded in an indirect fluorescence reaction, and 11.6% in a microprecipitation reaction in agar gel. Attention is drawn to the epizootological and economic importance of the study of ovine toxoplasmosis.

[An analysis of the correlation between the indices of uterine-placental blood flow and the blood enzymes in pregnant women with high perinatal risk]. / Analiz na korelatsionnnata vzaimovruzka mezhdu pokazatelite na matochno-platsentarniia kruvotok i niakoi fermenti na kruvta pri bremenni s goliam perinatalen risk.

The purpose of the present study was to analyse correlation interactions between parameters of uterine-placental blood flow (UPF) and some enzymes of blood of 77 pregnant women with high risk of perinatal pathology, divided into 4 groups. Eleven correlation connections between parameters of blood flow and enzymes of blood were found in the first group of pregnant women without disturbance in UPF. In the pregnant women with a reduction in blood flow in the region of the large uterine-placental vessels there was dissociation of a large part of the aforementioned correlation connections as only 4 ware preserved (26.67%). New correlation connections occurred between oxytocinase and parameters of UPF. We found dissociation of all correlation connections between parameters of UPF and blood enzymes in the third group of pregnant women with a reduction of UPF in the whole uterine-placental blood flow. New correlation connections between alkaline and thermostable phosphatase in parameters of UPF were formed. Ten out of eleven correlation connections dissociated in the four group of pregnant women with a reduction of UPF only in the intervillous space. New correlation connections were formed between parameters of UPF and hydroxybutyrate dehydrogenase and lactate dehydrogenase. Having in mind the performed analysis of correlation interconnections between parameters of UPF and some blood enzymes we could assume that activation of various enzymic systems, forming links of adaptation-compensatory mechanisms of the placental system, occurs in the development of placental insufficiency.

[Interrelation between the enzyme activity indices and the status of the uterine-placental blood flow in pregnant women at high risk for perinatal pathology]. / Vzaimna vruzka mezhdu pokazatelite na aktivnostta na niakoi fermenti i sustoianieto na matochno-platsentarniia kruvotok pri bremenni s visok risk ot perinatalna patologiia.

The aim of the present study was to examine metabolic processes in pregnant women with high risk of perinatal pathology during disturbance in the uterine-placental blood flow (UPF). We determined the following parameters for evaluation of the metabolic disturbances: alanine aminotransferase, hydroxybutyrate dehydrogenase, lactate dehydrogenase, creatine phosphokinase, alkaline phosphatase, thermostable alkaline phosphatase, oxytocinase and lipid peroxidation. The analysis of the obtained data showed that reduction in UPF, limited only in the region of the large uterine-placental blood vessels, was accompanied by a reduction in the activity of HBDH, LDG, CPC, but moderate increase in the whole uterine-placental blood bed was accompanied by the intravillous space, was accompanied by a moderate increase in HBDH, ADG, CPC and AP in comparison with pregnant women without disturbance in UPF, which however occurred in smaller activity of these enzymes both in disturbance in blood flow of intervillous space and in the region of the large uterine-placental blood vessels. These changes as a whole characterized borderline state of energetic metabolism in the organism of the pregnant woman, which in the final analysis assured comparatively favourable outcome of the pregnancy for the fetus.

[Central hemodynamics and kidney function in women with pre-eclampsia]. / Sustoianie na tsentralnata khemodinamika i bubrechnata funktsiia pri zheni s preeklampsiia.

A radionuclide method with quickly disintegrating 99MTC labelled human albumin and DTPA in a volume of 0.3-0.5 ml and activity of 37 mVk with two consecutive examinations of central and renal hemodynamics was used in 91 pregnant women with preeclampsia and pyelonephritis. Marked hypovolemia was found in all groups of investigated women with preeclampsia with the exception of the group of women with pyelonephritis. There was also difference in arterial pressure in women with preeclampsia I degree and pyelonephritis, which was statistically significant with advancement of gravity and duration of the disease. The investigation of the functional state of kidneys and blood flow showed a tendency to slowing both in the arterial and venous circulation in women with pre-eclampsia of pregnancy. In the pregnant women of this group and the women with pyelonephritis there was asymmetry in the curves of the blood flow as well as in the temporary indices of renal filtration, which were increases two-folds in comparison with the normal values. They were mostly manifested on the side of the involvement in women with pyelonephritis. Irradiation loading was 0.212 mZv of both examinations and was ten times less than that of x-ray pelvimetry.

[Comparative studies of the virulent and immunogenic properties of the Toxoplasma strains isolated from domestic animals]. / Sravnitelni prouchvaniia vurkhu virulentnite i imunogennite svoistva na shtamove toksoplazmi, izolirani ot domashni zhivotni.

Comparative investigations were carried out on the virulent and immunogenic properties of 5 cytogenic Toxoplasma strains (3 isolated from rabbits and 2--from fetuses of ewes that had miscarried). It was found that at shortening the interval of passage to 7--10 days and increasing the amount of the inoculate the virulence of the strains rose. Particularly virulent for albino mice proved the oocysts of T. gondii obtained after the feeding of kittens with cysts. The role was confirmed of Toxoplasma organisms in the etiology of abortions observed in experimentally infected guinea pigs and sheep. There were in the placenta and the brain of aborted fetuses characteristic histopathologic changes. Immunologic studies revealed that the isolated strains were immunologically identical.