Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects on central hemodynamics and skeletal muscle metabolism during surgery for abdominal aortic aneurysm were compared in 6 patients given a preoperative adrenergic block (group B) and in 6 patients who additionally had a temporary brachio-femoro-femoral by-pass during the aortic clamping (group B + S). The cardiac output, heart rate, arterial and pulmonary artery pressures and the cardiac filling pressure were studied. Biopsy specimens from the lateral vastus muscle and blood samples from the radial artery and the iliac vein were taken before aortic clamping and also before and 30 minutes, 4 and 16 hours after the aortic declamping. Intramuscular temperature and pH were measured. The glycogen, glucose, lactate, pyruvate, ATP, ADP, AMP, phosphocreatine (PCr) and creatine (Cr) contents of the muscle and the lactate and pyruvate concentration in iliac venous and radial arterial blood were determined, using enzymatic fluorometric techniques. In group B, aortic clamping induced severe temporary incomplete ischemia with a 300% increase in lactate/pyruvate (L/P) ratio and a fall in intramuscular pH (pHm). The adenylate energy charge (EC) decreased, but the creatine (PCr + CR) and the adenylate (ATP + ADP + AMP) pool remained unchanged. After aortic declamping, the L/P ratio, EC and pHm regained their preclamping values, but the pools of energy phosphate compounds were reduced, indicating dysfunction or damage of the muscle cells. In group B + S there were no major muscle metabolic changes during clamping or after declamping of the aorta. In group B the systemic vascular resistance (SVR), mean arterial blood pressure (MAP) and left ventricular stroke work (LVSW) increased during the occlusion. On release of the clamp, cardiac output rose, possibly due to the sudden reduction of SVR. A temporary marked fall of MAP occurred. In group B + S, no increase of SVR, MAP or LVSW was observed during aortic clamping. After the declamping, only a minor MAP drop was observed. In both groups, a brief rise in pulmonary vascular resistance after the aortic declamping suggested transient pulmonary microembolism. If a high-risk patient is to undergo reconstructive surgery of the abdominal aorta and/or technical difficulties can be expected to necessitate prolonged cross-clamping during the operation, a temporary extracorporeal by-pass may be a favorable adjuvant, improving cardiac performance and preventing derangement of muscle metabolism.
 ...
PMID:Temporary incomplete ischemia of the legs induced by aortic clamping in man. Metabolic and hemodynamic effects of temporary extracorporeal by-pass. 613 73

Glutathione (GSH) is an important endogenous scavenger against reactive oxygen species. Elective abdominal surgery without ischemia and reperfusion leads to decreased muscle GSH concentrations 4-72 hr postoperatively without altering GSH redox status. In the present study, we investigated to what extent muscle GSH status was affected during and following elective abdominal aortic aneurysm repair. From patients (n = 10) undergoing abdominal aortic repair, thigh muscle specimens were taken preoperatively, at maximal ischemia, and at 10 min and 4, 24, and 48 hr of reperfusion. Specimens were analyzed for GSH, amino acids, and energy-rich compounds. At maximal ischemia, phosphocreatine decreased by 37% (p < 0.05) and lactate and creatine increased by 274% and 57% (p < 0.001 and 0.05), respectively, indicating ischemia during the clamping of aorta. Adenosine triphosphate, on the other hand, remained unaltered during the entire study period. Total GSH (tGSH) decreased by 46% at 24 hr and by 43% at 48 hr of reperfusion (p < 0.001), while reduced GSH decreased by 48% at 24 hr and by 44% at 48 hr (p < 0.001). The redox status (GSH/tGSH) of GSH and oxidized GSH remained unaltered. Among the constituent amino acids of GSH, glycine and cysteine remained unaltered while glutamine and glutamate decreased by 55% and 55%, respectively (p < 0.001). Abdominal aortic aneurysm repair induces metabolic alterations characteristic for ischemia. The antioxidative capacity in terms of muscle levels of GSH was decreased. However, the oxidative stress during reperfusion did not change GSH status more than what has been reported following abdominal surgery without ischemia and reperfusion. The results indicate that the oxidative stress elicited by elective abdominal aortic aneurysm repair is outbalanced by a compensated GSH metabolism not giving rise to an increased amount of oxidized GSH or an altered GSH redox status.
 ...
PMID:Effects on skeletal muscle glutathione status of ischemia and reperfusion following abdominal aortic aneurysm surgery. 1637 52