ABSTRACT
Levels of lactate, inorganic phosphate and uric acid in arterial, mixed venous and coronary sinus blood were studied in patients during open-heart surgery. It was found that the determination of mentioned biochemical parameters can provide information regarding the energetic metabolism status of the whole organism, but selectively, also of the patient's myocardium. The results of biochemical analyses demonstrate a significant loading of the organism manifested by metabolic alterations, especially after long-term cardiopulmonary bypass. The study of mentioned biochemical parameters can be employed for investigation of a more efficient protection of myocardium against ischemia-reperfusion injury. (Fig. 6, Ref. 18).
Subject(s)
Cardiac Surgical Procedures , Energy Metabolism , Humans , Lactates/blood , Phosphates/blood , Uric Acid/bloodABSTRACT
Investigation of cardiosurgical patients have provided evidence for the generation of free oxygen radicals during open heart surgery. The finding of increased plasma malondialdehyde concentrations, considered to be an indicator of lipid peroxidation in cell membranes, is suggestive of this process. Simultaneously, the antiradical capacity of tissue was found to exhibit a decreasing trend, as established by the levels of superoxide dismutase and catalase in erythrocytes of peripheral blood which tended to diminish. The funding that no changes in the studied parameters were observed in the blood from the coronary sinus taken before and after interruption of coronary blood flow demonstrates that the commonly applied protection of the myocardium by hypothermic cardioplegic solution and topical cooling of the heart is effective in suppressing radical formation. (Fig. 5, Ref. 36.)
Subject(s)
Cardiac Surgical Procedures , Catalase/blood , Free Radicals/metabolism , Malondialdehyde/blood , Superoxide Dismutase/blood , Adult , Humans , Intraoperative Period , Middle AgedABSTRACT
The purpose of the investigation was: 1. to examine the effect of cardiopulmonary bypass (CPB) on the generation of cytotoxic oxygen-derived radicals and 2. to determine if the pretreatment of patients with vitamins E and C will combat generation of such radicals. Twenty patients undergoing CPB for treatment of cardiac disease were entered into the study and randomized to one of two groups. Group 1 (n = 9) served as control. Group 2 (n = 11) consisted of patients pretreated with 2000 IU of vitamin E 12 h prior to surgical intervention and 2 g of vitamin C given in the morning on the day of operation. Blood samples from arterial and mixed venous blood for analysis were obtained at the following intervals: 1. before anesthesia, 2. before sternotomy, 3. at the start of CPB, 4. at the end of CPB, 5. at the time of skin closure, 6. in the morning of the following day. Blood specimens from the coronary sinus were withdrawn A--before aortic cross-clamping, B--immediately after aortic declamping, C--in the 5th min, and D--in the 15th min of reperfusion. The concentration of inorganic phosphate as well as of uric acid was significantly higher in the control group what might indicate that vitamins E and C attenuate the degradation of adenine nucleotides. The most important difference between treated and control groups was observed in plasma concentration of malondialdehyde--a marker of lipid peroxidation--which was significantly lower in pretreated patients. A similar pattern of changes was found in the level of the lysosomal enzyme N-acetyl-glucosaminidase. Finally, pretreatment with vitamins E and C inhibited the decrease of catalase, observed in controls.