Murat Tumuklu

Bio: Murat Tumuklu is an academic researcher from Kent Hospital. The author has contributed to research in topics: Pulse wave velocity & Pulse pressure. The author has an hindex of 3, co-authored 4 publications receiving 302 citations.

The benefit of salt restriction in the treatment of end-stage renal disease by haemodialysis

Abstract: Background. Most haemodialysis (HD) centres use antihypertensive drugs for the management of hypertension, whereas some centres apply dietary salt restriction strategy. In this retrospective cross-sectional study, we assessed the effectiveness and cardiac consequences of these two strategies. Methods. We enrolled all patients from two dialysis centres, who had been on a standard HD programme at the same centre for at least 1 year. All patients underwent echocardiographic evaluation. Clinical data were obtained from patients’ charts. Centre A (n = 190) practiced ‘salt restriction’ strategy and Centre B (n = 204) practiced antihypertensive-based strategy. Salt restriction was defined as managing high blood pressure (BP) via lowering dry weight by strict salt restriction and insistent ultrafiltration without using anti-hypertensive drugs. Results. There was no difference regarding age, gender, diabetes, history of cardiovascular disease and efficiency of dialysis between centres. Antihypertensive drugs were used in 7% of the patients in Centre A and 42% in Centre B( P < 0.01); interdialytic weight gain was significantly lower in Centre A (2.29 ± 0.83 kgversus 3.31 ± 1.12 kg, P < 0.001). Mean systolic and diastolic blood pressures were similar in the two centres. However, Centre A had lower left ventricular (LV) mass (indexed for height 2.7 :5 9 ± 16 versus 74 ± 27 g/m 2.7 , P < 0.0001). The frequency of LV hypertrophy was lower in Centre A (74% versus 88%, P < 0.001). Diastolic and systolic functions were better preserved in Centre A. Intradialytic hypotension (hypotensive episodes/100 patient sessions) was more frequent in Centre B (11 versus 27, P <0.01). Conclusions. This cross-sectional study suggests that salt restriction and reduced prescription of antihypertensive drugs may limit LV hypertrophy, better preserve LV functions and reduce intradialytic hypotension in HD patients.

Comparison of 4- and 8-h dialysis sessions in thrice-weekly in-centre haemodialysis: A prospective, case-controlled study

Abstract: Background Longer dialysis sessions may improve outcome in haemodialysis (HD) patients. We compared the clinical and laboratory outcomes of 8- and 4-h thrice-weekly HD. Methods Two-hundred and forty-seven HD patients who agreed to participate in a thrice-weekly 8-h in-centre nocturnal HD (NHD) treatment and 247 age-, sex-, diabetes status- and HD duration-matched control cases to 4-h conventional HD (CHD) were enrolled in this prospective controlled study. Echocardiography and psychometric measurements were performed at baseline and at the 12th month. The primary outcome was 1-year overall mortality. Results Overall mortality rates were 1.77 (NHD) and 6.23 (CHD) per 100 patient-years (P = 0.01) during a mean 11.3 ± 4.7 months of follow-up. NHD treatment was associated with a 72% risk reduction for overall mortality compared to the CHD treatment (hazard ratio = 0.28, 95% confidence interval 0.09-0.85, P = 0.02). Hospitalization rate was lower in the NHD arm. Post-HD body weight and serum albumin levels increased in the NHD group. Use of antihypertensive medications and erythropoietin declined in the NHD group. In the NHD group, left atrium and left ventricular end-diastolic diameters decreased and left ventricular mass index regressed. Both use of phosphate binders and serum phosphate level decreased in the NHD group. Cognitive functions improved in the NHD group, and quality of life scores deteriorated in the CHD group. Conclusions Eight-hour thrice-weekly in-centre NHD provides morbidity and possibly mortality benefits compared to conventional 4-h HD.

Factors related to pulse wave velocity and augmentation index in chronic hemodialysis patients.

Abstract: Background: Augmentation index (AIx) and pulse wave velocity (PWV) are early markers of atherosclerotic vascular changes and also have been shown to be predictive of cardiovascular disease and total mortality. The aim of our study was to evaluate the relationship between PWV and AIx-HR75, which is the corrected form of AIx according to a heart rate of 75 beats/min, echocardiographic parameters and biochemical parameters in chronic hemodialysis (HD) patients. Subjects and methods: AIx-HR75 and PWV were measured in 556 HD patients by applanation tonometry using the SphygmoCor device. Results: The mean PWV and AIx-HR75 values of the study group were 10.2 ± 2.4 and 28.4 ± 10.2 m/s. A positive correlation was found between PWV and AIx-HR75 (r = 0.214, p = 0.000). AIx-HR75 correlated with age (r = 0.093, p = 0.028), body surface area (BSA) (r = −0.194, p = 0.000), mean arterial pressure (MAP) (r = 0.335, p = 0.000), pulse pressure (PP) (r = 0.212, p = 0.000), cardiothoracic index (r = 0.155, p = 0.016), and pre...

Oxidative Stress in Hemodialysis Patients: A Review of the Literature.

Abstract: Hemodialysis (HD) patients are at high risk for all-cause mortality and cardiovascular events. In addition to traditional risk factors, excessive oxidative stress (OS) and chronic inflammation emerge as novel and major contributors to accelerated atherosclerosis and elevated mortality. OS is defined as the imbalance between antioxidant defense mechanisms and oxidant products, the latter overwhelming the former. OS appears in early stages of chronic kidney disease (CKD), advances along with worsening of renal failure, and is further exacerbated by the HD process per se. HD patients manifest excessive OS status due to retention of a plethora of toxins, subsidized under uremia, nutrition lacking antioxidants and turn-over of antioxidants, loss of antioxidants during renal replacement therapy, and leukocyte activation that leads to accumulation of oxidative products. Duration of dialysis therapy, iron infusion, anemia, presence of central venous catheter, and bioincompatible dialyzers are several factors triggering the development of OS. Antioxidant supplementation may take an overall protective role, even at early stages of CKD, to halt the deterioration of kidney function and antagonize systemic inflammation. Unfortunately, clinical studies have not yielded unequivocal positive outcomes when antioxidants have been administered to hemodialysis patients, likely due to their heterogeneous clinical conditions and underlying risk profile.