Background: While chronic dialysis treatment has been suggested to increase pulmonary pressure values, right ventricular dysfunction (RVD) is a major cause of death in patients with end-stage renal disease. We investigated the impact of different dialysis treatments on right ventricular function. Methods: We examined 220 subjects grouped as follows: healthy controls (n = 100), peritoneal dialysis (PD; n = 26), hemodialysis (HD) with radial arteriovenous fistula (AVF; n = 62), and HD with brachial AVF (n = 32). Echocardiography including tissue Doppler imaging (TDI) of the right ventricle was performed in all patients. Results: Pulmonary pressure values progressively rose from controls across the 3 dialysis groups (21.7 ± 6.8, 29.7 ± 6.7, 37.9 ± 6.7 and 40.8 ± 6.6 mm Hg, respectively; p < 0.001). TDI indices of right ventricular function were more impaired in HD patients, particularly in those with brachial AVF. RVD, assessed by TDI myocardial performance index, was higher in HD patients compared with PD patients (71.3 vs. 34.6%, p < 0.001). Moreover, the prevalence of RVD further increased in patients with brachial AVF compared with the radial access (90.6 vs. 61.3%, p < 0.001). Conclusions: Compared to DP, HD increases the risk of RVD, particularly in the presence of brachial AVF. TDI may detect early functional failure of the right ventricle in HD patients.

Naratriptan 2.5 mg appears to prevent migraine headache when given early in prodrome. If headache occurs, severity appears to be reduced.

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IntroductionHaemodialysis has direct and indirect effects on skin and muscle microcirculatory regulation that are severe enough to worsen tolerance to physical exercise and muscle asthenia in patients undergoing dialysis, thus compromising patients' quality of life and increasing the risk of mortality. In diabetes these circumstances are further complicated, leading to an approximately sixfold increase in the incidence of critical limb ischaemia and amputation. Our aim in this study was to investigate in vivo whether haemodialysis induces major changes in skeletal muscle oxygenation and blood flow, microvascular compliance and tissue metabolic rate in patients with and without diabetes.MethodsThe study included 20 consecutive patients with and without diabetes undergoing haemodialysis at Sant Andrea University Hospital, Rome from March to April 2007. Near-infrared spectroscopy (NIRS) quantitative measurements of tissue haemoglobin concentrations in oxygenated [HbO2] and deoxygenated forms [HHb] were obtained in the calf once hourly for 4 hours during dialysis. Consecutive venous occlusions allowed one to obtain muscular blood flow (mBF), microvascular compliance and muscle oxygen consumption (mVO2). The tissue oxygen saturation (StO2) and content (CtO2) as well as the microvascular bed volume were derived from the haemoglobin concentration. Nonparametric tests were used to compare data within each group and among the groups and with a group of 22 matched healthy controls.ResultsThe total haemoglobin concentration and [HHb] increased significantly during dialysis in patients without and with diabetes. Only in patients with diabetes, dialysis involved a [HbO2], CtO2 and increase but left mVO2 unchanged. Multiple regression StO2 analysis disclosed a significant direct correlation of StO2 with HbO2 and an inverse correlation with mVO2. Dialysis increased mBF only in diabetic patients. Microvascular compliance decreased rapidly and significantly during the first hour of dialysis in both groups.ConclusionsOur NIRS findings suggest that haemodialysis in subjects at rest brings about major changes in skeletal muscle oxygenation, blood flow, microvascular compliance and tissue metabolic rate. These changes differ in patients with and without diabetes. In all patients haemodialysis induces changes in tissue haemoglobin concentrations and microvascular compliance, whereas in patients with diabetes it alters tissue blood flow, tissue oxygenation (CtO2, [HbO2]) and the metabolic rate (mVO2). In these patients the mVO2 is correlated to the blood supply. The effects of haemodialysis on cell damage remain to be clarified. The absence of StO2 changes is probably linked to an opposite [HbO2] and mVO2 pattern.

An increase in laboratory findings of muscle injury postoperatively, especially serum myoglobin concentration, predicts the incidence of acute kidney injury and renal replacement therapy requirement, as reported in other surgical settings. Perioperative myocardial injury cannot totally explain the occurrence of increased myoglobinemia. These results suggest an important role of skeletal muscle breakdown and necrosis in determining an increased myoglobinemia concentration after coronary artery bypass grafting.