RESUMEN
After the publication of our paper Dunlop et al. "Rationale and design of the Sodium Lowering In Dialysate (SoLID) trial: a randomised controlled trial of low versus standard dialysate sodium concentration during hemodialysis for regression of left ventricular mass", we became aware of further data correlating left ventricular (LV) mass index at baseline and their corresponding mass at 12 months, using cardiac magnetic resonance imaging (MRI) in patients on hemodialysis. The original published sample size for the SoLID trial of 118 was a conservative estimate, calculated using analysis of covariance and a within person Pearson's correlation for LV mass index of 0.75. New data communicated to the SoLID trial group has resulted in re-calcuation of the sample size, based upon a within person Pearson's correlation of 0.8 but otherwise unchanged assumptions. As a result, the SoLID trial will now recruit 96 participants.
Asunto(s)
Soluciones para Diálisis/química , Proyectos de Investigación , Tamaño de la Muestra , Sodio/administración & dosificación , Ventrículos Cardíacos/patología , Humanos , Imagen por Resonancia Magnética , Tamaño de los Órganos , Diálisis RenalRESUMEN
BACKGROUND: The Sodium Lowering in Dialysate (SoLID) trial is an ongoing a multi-center, prospective, randomised, single-blind (assessor), controlled, parallel assignment clinical trial, enrolling 96 home and self-care hemodialysis (HD) patients from 7 centers in New Zealand. The trial will evaluate the hypothesis that lower dialysate [Na+] during HD results in lower left ventricular (LV) mass. Since it's inception, observational evidence has suggested increased mortality risk with lower dialysate [Na+], possibly due to exacerbation of intra-dialytic hypotension and subsequent myocardial micro-injury. The Myocardial Micro-injury and Cardiac Remodeling Extension Study in the Sodium Lowering In Dialysate Trial (Mac-SoLID study) aims to determine whether lower dialysate [Na+] results in (i) increased levels of high-sensitivity Troponin T (hsTnT), a well-established marker of intra-dialytic myocardial micro-injury in HD populations, and (ii) increased fixed LV segmental wall motion abnormalities, a marker of recurrent myocardial stunning and micro-injury, and (iii) detrimental changes in LV geometry due to maladaptive homeostatic mechanisms. METHODS/DESIGN: The SoLID trial and the Mac-SoLID study are funded by the Health Research Council of New Zealand. Key exclusion criteria: patients who dialyse > 3.5 times per week, pre-dialysis serum sodium <135 mM, and maintenance haemodiafiltration. In addition, some medical conditions, treatments or participation in other dialysis trials that contraindicate the study intervention or confound its effects, will be exclusion criteria. The intervention and control groups will receive dialysate sodium 135 mM and 140 mM respectively, for 12 months. The primary outcome measure for the Mac-SOLID study is repeated measures of [hsTnT] at 0, 3, 6, 9, and 12 months. The secondary outcomes will be assessed using cardiac magnetic resonance imaging (MRI), and comprise LV segmental wall motion abnormality scores, LV mass to volume ratio and patterns of LV remodeling at 0 and 12 months. DISCUSSION: The Mac-SoLID study enhances and complements the SoLID trial. It tests whether potential gains in cardiovascular health (reduced LV mass) which low dialysate [Na+] is expected to deliver, are counteracted by deterioration in cardiovascular health through alternative mechanisms, namely repeated LV stunning and micro-injury. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry number: ACTRN12611000975998.
Asunto(s)
Vasos Coronarios/efectos de los fármacos , Soluciones para Diálisis/administración & dosificación , Microcirculación/efectos de los fármacos , Diálisis Renal/métodos , Sodio/administración & dosificación , Remodelación Ventricular/efectos de los fármacos , Vasos Coronarios/fisiología , Soluciones para Diálisis/efectos adversos , Femenino , Humanos , Masculino , Microcirculación/fisiología , Nueva Zelanda/epidemiología , Estudios Prospectivos , Diálisis Renal/efectos adversos , Autocuidado/métodos , Método Simple Ciego , Sodio/efectos adversos , Remodelación Ventricular/fisiologíaRESUMEN
BACKGROUND: The current literature recognises that left ventricular hypertrophy makes a key contribution to the high rate of premature cardiovascular mortality in dialysis patients. Determining how we might intervene to ameliorate left ventricular hypertrophy in dialysis populations has become a research priority. Reducing sodium exposure through lower dialysate sodium may be a promising intervention in this regard. However there is clinical equipoise around this intervention because the benefit has not yet been demonstrated in a robust prospective clinical trial, and several observational studies have suggested sodium lowering interventions may be deleterious in some dialysis patients. METHODS/DESIGN: The Sodium Lowering in Dialysate (SoLID) study is funded by the Health Research Council of New Zealand. It is a multi-centre, prospective, randomised, single-blind (outcomes assessor), controlled parallel assignment 3-year clinical trial. The SoLID study is designed to study what impact low dialysate sodium has upon cardiovascular risk in dialysis patients. The study intends to enrol 118 home hemodialysis patients from 6 sites in New Zealand over 24 months and follow up each participant over 12 months. Key exclusion criteria are: patients who dialyse more frequently than 3.5 times per week, pre-dialysis serum sodium of <135 mM, and maintenance hemodiafiltration. In addition, some medical conditions, treatments or participation in other dialysis trials, which contraindicate the SoLID study intervention or confound its effects, will be exclusion criteria. The intervention and control groups will be dialysed using dialysate sodium 135 mM and 140 mM respectively, for 12 months. The primary outcome measure is left ventricular mass index, as measured by cardiac magnetic resonance imaging, after 12 months of intervention. Eleven or more secondary outcomes will be studied in an attempt to better understand the physiologic and clinical mechanisms by which lower dialysate sodium alters the primary end point. DISCUSSION: The SoLID study is designed to clarify the effect of low dialysate sodium upon the cardiovascular outcomes of dialysis patients. The study results will provide much needed information about the efficacy of a cost effective, economically sustainable solution to a condition which is curtailing the lives of so many dialysis patients. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry number: ACTRN12611000975998.
Asunto(s)
Soluciones para Diálisis/administración & dosificación , Hemodiálisis en el Domicilio/métodos , Hipertrofia Ventricular Izquierda/prevención & control , Fallo Renal Crónico/terapia , Sodio/administración & dosificación , Soluciones para Diálisis/química , Estudios de Seguimiento , Hemodiálisis en el Domicilio/efectos adversos , Humanos , Hipertrofia Ventricular Izquierda/epidemiología , Fallo Renal Crónico/epidemiología , Nueva Zelanda/epidemiología , Estudios Prospectivos , Diálisis Renal/efectos adversos , Diálisis Renal/métodos , Método Simple Ciego , Sodio/química , Resultado del TratamientoRESUMEN
BACKGROUND: Insertion of percutaneous hemodialysis catheters is an invasive procedure with a small but definite risk of morbidity and mortality. OBJECTIVES: Assessing potential benefits of using real-time 2-dimensional Doppler ultrasound imaging guidance for the insertion of hemodialysis catheters compared with insertion based solely on anatomic landmarks. STUDY DESIGN: Systematic review and meta-analysis of randomized controlled trials. DATA SOURCES: MEDLINE (1966 to July 2010), EMBASE (1980 to July 2010), Cochrane Renal Group Specialised Register, and Cochrane Central Register of Controlled Trials (CENTRAL). SETTING & POPULATION: Patients requiring hemodialysis catheter insertion. SELECTION CRITERIA FOR STUDIES: We included all randomized controlled trials regardless of publication status or language. INTERVENTIONS: Real-time 2-dimensional Doppler ultrasound image guidance. OUTCOMES: Catheter placement failures, catheters failed to be placed in the first attempt, attempts per catheter inserted, time taken for successful venous puncture, and complications (carotid artery puncture, pneumo- or hemothorax, neck hematoma, and brachial plexus injury). Treatment effects were summarized with the RR measure for dichotomous outcomes and mean difference for continuous outcomes. RESULTS: 7 trials with 830 catheters were identified. Ultrasound guidance significantly decreased the risk of the following outcomes: catheter placement failure (7 studies, 830 catheters; RR, 0.12; 95% CI, 0.04-0.37), failure to place catheter on first attempt (5 studies, 595 catheters; RR, 0.40; 95% CI, 0.29-0.56), arterial punctures (6 trials, 785 catheters; RR, 0.22; 95% CI, 0.06-0.81), and hematoma formation (4 trials, 323 catheters; RR, 0.27; 95% CI, 0.08-0.88). It also significantly decreased the time to cannulate the vein (1 trial, 73 catheters; mean difference, -1.40; 95% CI, -2.17 to -0.63), and number of attempts per catheter insertion (1 trial, 110 catheters; mean difference, -0.35; 95% CI, -0.54 to -0.16). LIMITATIONS: Only 7 studies were identified, of which 3 were reported in only a conference abstract form. Some outcomes were reported in only 1 study. CONCLUSIONS: Use of real-time Doppler ultrasound guidance has benefits with respect to several important clinical outcomes, and its routine use in the insertion of hemodialysis catheters is strongly recommended.