Assessment of volume status with bioimpendance prior to hemodialysis and its importance for predicting survival in hemodialysis patients.

BACKGROUND: Optimal fluid management is a physician's everyday challenge in patients on maintenance hemodialysis (HD). Bioimpedance spectroscopy (BIS) is a non-invasive method to estimate body composition, including estimates of fluid overload (FO). Our study aimed to analyze the association between FO and the mortality rate in HD patients. MATERIALS AND METHODS: We performed a retrospective single-center cohort study in 92 HD patients. The body composition was measured before HD using the portable whole-body BIS device Body Composition Monitor (BCM). We have analyzed the mortality rates of HD patients in two FO groups, a standard definition FO group (> 1.1 L), and a severe FO group (> 2.5 L) and compared them to mortality rates of patients without FO or without severe FO, respectively. RESULTS: The mean age of patients was 64.3 ± 13.0 years, mean dialysis vintage 64 months, 60.9% were men. 68 (73.9%) patients had FO of > 1.1 L and 30 (32.6%) had FO of > 2.5 L. During the follow-up period of 1,020 ± 417 days, 29 (31.5%) patients died. Kaplan-Meier survival analysis showed that patients with FO > 2.5 L had worse survival (p = 0.039). In a Cox regression model, which included FO > 2.5 L, age, dialysis vintage, hemoglobin, C-reactive protein, and albumin, only FO > 2.5 L and advanced age turned out to be predictors of death (p = 0.044 and p = 0.001, respectively). CONCLUSION: HD patients with FO > 2.5 L before HD have poorer survival than patients with normohydration or lower overhydration.

Diabetic patients with chronic kidney disease: Non-invasive assessment of cardiovascular risk.

The prevalence and burden of diabetes mellitus and chronic kidney disease on global health and socioeconomic development is already heavy and still rising. Diabetes mellitus by itself is linked to adverse cardiovascular events, and the presence of concomitant chronic kidney disease further amplifies cardiovascular risk. The culmination of traditional (male gender, smoking, advanced age, obesity, arterial hypertension and dyslipidemia) and non-traditional risk factors (anemia, inflammation, proteinuria, volume overload, mineral metabolism abnormalities, oxidative stress, etc.) contributes to advanced atherosclerosis and increased cardiovascular risk. To decrease the morbidity and mortality of these patients due to cardiovascular causes, timely and efficient cardiovascular risk assessment is of huge importance. Cardiovascular risk assessment can be based on laboratory parameters, imaging techniques, arterial stiffness parameters, ankle-brachial index and 24 h blood pressure measurements. Newer methods include epigenetic markers, soluble adhesion molecules, cytokines and markers of oxidative stress. In this review, the authors present several non-invasive methods of cardiovascular risk assessment in patients with diabetes mellitus and chronic kidney disease.

Lung Ultrasound-Guided Dry Weight Assessment and Echocardiographic Measures in Hypertensive Hemodialysis Patients: A Randomized Controlled Study.

RATIONALE & OBJECTIVE: Left ventricular (LV) hypertrophy and dysfunction are associated with adverse outcomes in hemodialysis patients. Hypertension and hypervolemia play important roles in these cardiac abnormalities. We report on the prespecified secondary outcome, echocardiographic indexes of LV function, from a previously reported study of the effect of lung ultrasound (US)-guided dry weight reduction on systolic blood pressure. STUDY DESIGN: Single-blind randomized trial. SETTINGS & PARTICIPANTS: 71 clinically euvolemic hypertensive hemodialysis patients in Greece and Slovenia. INTERVENTION: The active intervention group's (n=35) volume removal was guided by the total number of lung US B-lines observed every week before a midweek dialysis session. The usual-care group (n=36) was treated using standard-of-care processes that did not include acquisition of US data. OUTCOMES: 2-dimensional and tissue Doppler echocardiographic indexes at baseline and study end (8 weeks) that evaluated left and right heart chamber sizes, as well as systolic and diastolic function. RESULTS: Overall, 19 (54%) patients in the active intervention and 5 (14%) in the usual-care group had ultrafiltration intensification (P<0.001) during follow-up; changes in US B-lines (-5.3±12.5 vs+2.2±7.6; P<0.001) and dry weight (-0.71±1.39 vs+0.51±0.98kg; P<0.001) significantly differed between the active and usual-care groups. Inferior vena cava diameter decreased in the active compared with the usual-care group (-0.43±4.00 vs 0.71±4.82cm; P=0.03) at study end. Left (LA) and right (RA) atrial dimensions decreased more in the active group (LA surface, -1.09±4.61 vs 0.93±3.06cm2; P=0.03; RA surface -1.56±6.17 vs 0.47±2.31; P=0.02). LA volume index nominally decreased more in the active group (-2.43±13.14 vs 2.95±9.42mL/m2), though this was of borderline statistical significance (P=0.05). Reductions in LV end-diastolic diameter and volume were marginally greater in the active group. The change in LV filling pressures was significantly different in the active compared with the usual-care group (early transmitral diastolic velocities ratio [E/e'], -0.38±3.14 vs 1.36±3.54; P=0.03; E wave deceleration time, 35.43±85.25 vs-18.44±50.69; P=0.002]. Systolic function indexes were unchanged in both groups. In multivariable analysis, US B-line reduction was associated with a reduction in the E/e' LV ratio (OR, 4.542; 95% CI, 1.266-16.292; P=0.02). LIMITATIONS: Exploratory study; small sample size. CONCLUSIONS: A US-guided strategy for dry weight reduction is associated with decreased cardiac chamber dimensions and LV filling pressure, but no difference in systolic performance compared with usual care in hypertensive hemodialysis patients. FUNDING: European Renal Association-European Dialysis and Transplant Association. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT03058874.

The assessment of acute kidney injury in critically ill patients.

Acute kidney injury (AKI) is common in critically ill patients and is associated with high morbidity and mortality. The availability of several biomarkers of kidney injury offers new tools for its early recognition and management. The early identification of high-risk patients provides an opportunity to develop strategies for the prevention, early diagnosis and treatment of AKI. Despite progress in critical care medicine over the past decade, the treatment strategies for AKI in critically ill patients, such as when to start renal replacement therapy, remain controversial. A recently proposed risk prediction score for AKI, based on routinely available clinical variables, presents a new means of identifying patients at high risk of AKI.

Radiographic assessment of vascular calcification, aortic pulse wave velocity, ankle-brachial index and fibroblast growth factor-23 in chronic hemodialysis patients.

Vascular calcification is a frequent complication of chronic kidney disease and end stage renal disease. In both the general population and patients with end stage renal disease, vascular calcification is related to arterial stiffness and is a predictor of cardiovascular morbidity and mortality. Various diagnostic methods are currently used to assess vascular calcification. There is a preference for simple, reliable methods that can be used in daily practice. Therefore, several imaging and laboratory methods are investigated. Twenty-eight patients with mean age of 62 years on chronic hemodialysis were enrolled in the study. The mean duration of hemodialysis treatment was 70 months (range 3 to 350 months). Vascular calcification was assessed with coronary computed tomography and lateral lumbar, pelvic and hand radiographs. Vascular stiffness was evaluated using aortic pulse wave velocity and ankle-brachial index measurements, and finally serum levels of fibroblast growth factor-23 were followed. A statistically significant correlation was demonstrated between all the following parameters: coronary artery calcification score, aortic pulse wave velocity, abdominal aortic calcification score, simple vascular calcification scores in pelvis and hand. A statistically significant correlation of ankle-brachial index >1.3 to coronary artery calcification score was found. There was no correlation between the previous parameters and fibroblast growth factor-23. The results of our study indicate that simple imaging methods could provide confident vascular damage assessment and therefore potentially guide therapy adjustments. An association between fibroblast growth factor-23 and the other diagnostic modalities in our study was not found.