Immersion-enhanced fluid redistribution can prevent intradialytic hypotension: A prospective, randomized, crossover clinical trial.

INTRODUCTION: Intradialytic hypotension (IDH) is an important cause of morbidity and mortality among hemodialysis patients. We used an immersion model to evaluate the role of reduced effective circulating volume, and to examine whether facilitated refilling can prevent IDH. METHODS: Ten male hemodialysis patients who had frequent episodes of IDH were randomized to a mid-week "wet" or "dry" hemodialysis session, and subsequently underwent the other session in a crossover manner. The wet sessions were performed while immersed up to the neck in a 34 to 35°C bath, and the dry session was standard hemodialysis. Ultrafiltration goals were determined as the mean ultrafiltration during the 10 sessions preceding the first study session ± 10%. FINDINGS: Mean ultrafiltration was similar for the wet and dry sessions (2.99 ± 0.64 kg vs. 2.96 ± 0.74 kg). Symptomatic hypotension did not develop in any of the patients during the wet session, compared to 4 (40%) during the dry session. Systolic blood pressure adjusted to ultrafiltration was stable during the wet session, 0.22 mmHg/15 min (95% CI -0.27 to 0.70), P = 0.38, and significantly decreased during the dry session, -0.68 mmHg/15 min (95%CI -1.24 to -0.11), P = 0.02. Diastolic blood pressure did not change during the sessions. Mean atrial natriuretic peptide significantly increased in the wet session, by 31.36 pgr/mL (95%CI 8.73-53.99), P = 0.007, and slightly and insignificantly decreased in the dry session, by 21.66 pgr/mL (95% CI -52.59 to 9.25), P = 0.167. Aldosterone blood levels did not change. DISCUSSION: Reduced effective circulating volume is a major cause for IDH, which can be prevented using head-out water immersion facilitated redistribution.

Estimating of Residual Kidney Function by Multi-Frequency Bioelectrical Impedance Analysis in Hemodialysis Patients Without Urine Collection.

BACKGROUND/AIMS: Residual kidney function (RKF) is a pivotal predictor of better clinical outcomes in maintenance hemodialysis (MHD) patients. So far there has been no attempt to use bioimpedance analysis (BIA) measurements to calculate residual glomerular filtration rate (GFR) in dialysis population. We hypothesized that performing of multi-frequency BIA at the beginning and end of hemodialysis session can enable us to predict the measured residual GFR in MHD patients. Thus our aim was to develop and validate a new RKF prediction equation using multi-frequency BIA in MHD patients. METHODS: It was diagnostic test evaluation study in a prospective cohort. Participants (n=88; mean age, 66.3±13.2 years, 59.1% males) were recruited from a single hemodialysis center. A new equation (eGFRBIA) to predict RKF, utilizing BIA measurements performed pre- and post-dialysis, was generated and cross-validated by the leave-one-out procedure. GFR estimated as the mean of urea and creatinine clearance (mGFR) using urine collections during entire interdialytic period. RESULTS: A prediction equation for mGFR that includes both pre- and post-dialysis BIA measurements provided a better estimate than either pre- or post-dialysis measurements alone. Mean bias between predicted and measured GFR was -0.12 ml/min. Passing and Bablok regression showed no bias and no significant deviation in linearity. Concordance correlation coefficient indicated good agreement between the eGFRBIA and mGFR (0.75, P<0.001). Using cut-off predicted mGFR levels >2 ml/min/1.73 m2 yielded an area under curve of 0.96, sensitivity 85%, and specificity 89% in predicting mGFR. The κ scores for intraobserver reproducibility were consistent with substantial agreement between first and second estimation of RKF according to eGFRBIA (weighted κ was 0.60 [0.37-0.83]). CONCLUSION: We present a valid and clinically obtainable method to predict RKF in MHD patients. This method, which uses BIA, may prove as accurate, convenient and easily reproducible while it is operator independent.

A single center, open-label, randomized, parallel group study assessing the relationship between asymptomatic bacteriuria and inflammation in maintenance hemodialysis patients.

INTRODUCTION: The significance of asymptomatic bacteriuria in maintenance hemodialysis (MHD) patients remains controversial. We hypothesized that the presence of asymptomatic bacteriuria as a sole clinical manifestation of urinary tract infection (UTI) in asymptomatic MHD patient may contribute to the chronic inflammatory response. Our aim was to explore the relationship between asymptomatic bacteriuria and elevated levels of inflammatory markers in MHD patients. METHODS: A randomized open-label single center study of 114 MHD patients was conducted. Forty-six patients presented negative urine culture and 41 subjects were excluded due to different reasons. The remaining 27 patients (mean age of 71.5 ± 12.2 years, 63% men), fulfilling the criteria for having asymptomatic bacteriuria, were randomly assigned to either the treatment group (13 patients) or the observational group (14 subjects). The treatment group received 7 days of antibiotic treatment given according to bacteriogram sensitivity. After 3 months of follow-up all measurements of the study were repeated. The primary end point was change in inflammatory biomarkers from baseline by the end of the study. FINDINGS: There were no statistically significant differences in white blood cell changes (P = 0.27), ferritin (P = 0.09), C-reactive protein (P = 0.90), and interleukin-6 (P = 0.14) levels between the groups from baseline to the end of study or at the end of the study. Analyzing cross-sectional data, asymptomatic bacteriuria was found to not be a predictor of higher levels of inflammatory parameters at baseline. DISCUSSION: Asymptomatic bacteriuria is not a modifiable risk factor for chronic inflammation in the MHD population.