Validation of the SMH Equations for the Estimation of the Total Body Water Volume in Hemodialysis Patients.

Background: Online dialysis clearance monitors typically provide an accurate value for Kt. A value for V (total body water [TBW]) is required to calculate Kt/V, the measure of the adequacy of the delivered dialysis in hemodialysis (HD) patients. Using bioimpedance spectroscopy (BIS), we previously developed 2 sex-specific equations for the estimation of the TBW, which we have chosen to name the St Michael's Hospital (SMH) equations.

Left ventricular strain analysis using cardiac magnetic resonance imaging in patients undergoing in-centre nocturnal haemodialysis.

Aim: Intensified haemodialysis is associated with regression of left ventricular (LV) mass. Compared to LV ejection fraction, LV strain allows more direct assessment of LV function. We sought to assess the impact of in-centre nocturnal haemodialysis (INHD) on global LV strain (radial, circumferential, and longitudinal) and torsion by cardiac MRI (CMR).

Extended Duration Nocturnal Hemodialysis and Changes in Plasma Metabolite Profiles.

Background And Objectives: In-center, extended duration nocturnal hemodialysis has been associated with variable clinical benefits, but the effect of extended duration hemodialysis on many established uremic solutes and other components of the metabolome is unknown. We determined the magnitude of change in metabolite profiles for patients on extended duration nocturnal hemodialysis.

Design, Setting, Participants, & Measurements: In a 52-week prospective, observational study, we followed 33 patients receiving conventional thrice weekly hemodialysis who converted to nocturnal hemodialysis (7-8 hours per session, three times per week).

Volume Estimates in Chronic Hemodialysis Patients by the Watson Equation and Bioimpedance Spectroscopy and the Impact on the Kt/V calculation.

Background: Accurate assessment of total body water (TBW) is essential for the evaluation of dialysis adequacy (Kt/V). The Watson formula, which is recommended for the calculation of TBW, was derived in healthy volunteers thereby leading to potentially inaccurate TBW estimates in maintenance hemodialysis recipients. Bioimpedance spectroscopy (BIS) may be a robust alternative for the measurement of TBW in hemodialysis recipients.

Sodium-Reduced Meat and Poultry Products Contain a Significant Amount of Potassium from Food Additives.

Background: Sodium-reduced packaged food products are increasingly available to consumers; however, it is not clear whether they are suitable for inclusion in a potassium-reduced diet. For individuals with impaired renal potassium excretion caused by chronic kidney disease and for those taking certain medications that interfere with the rennin-angiotensin aldosterone axis, the need to limit dietary potassium is important in view of the risk for development of hyperkalemia and fatal cardiac arrhythmias.

Objective: The primary objective of this study was to determine the impact of the reduction of sodium in packaged meat and poultry products (MPPs) on the content of potassium and phosphorus from food additives.

Frailty and the Quality of Life in Hemodialysis Patients: The Importance of Waist Circumference.

Objective: Frailty among the end-stage renal disease (ESRD) population is highly prevalent and has been associated with mortality. Little is known about the relation of different aspects of body composition, a modifiable risk factor, with the risk of frailty in ESRD population.

Design And Methods: One hundred and fifty-one patients including 85 men and 66 women, aged ≥18 years with ESRD who had been receiving conventional maintenance hemodialysis (HD) for at least 3 months were included.

Association between conversion to in-center nocturnal hemodialysis and right ventricular remodeling.

Background: In-center nocturnal hemodialysis (INHD) is associated with favorable left ventricular (LV) remodeling. Although right ventricular (RV) structure and function carry prognostic significance, the impact of dialysis intensification on RV is unknown. Our objectives were to evaluate changes in RV mass index (MI), end-diastolic volume index (EDVI), end-systolic volume index (ESVI) and ejection fraction (EF) after conversion to INHD and their relationship with LV remodeling.

Coincidence of role expectations between staff and volunteer members of drug free community coalitions.

Community coalitions have proliferated as a means of addressing a range of complex community problems. Such coalitions often consist of a small paid staff and volunteer members. The present study examines one likely contributor to coalition effectiveness: the degree of agreement on role expectations between paid staff and volunteer members.

Nutritional status after conversion from conventional to in-centre nocturnal hemodialysis.

Introduction: Recipients of conventional hemodialysis (CHD; 3-4 h/session, 3 times/week) experience volume expansion and nutritional impairment which may contribute to high mortality. Prolongation of sessions with in-centre nocturnal hemodialysis (INHD; 7-8 h/session, 3 times/week) may improve clinical outcomes by enhancement of ultrafiltration and uremic toxin removal.

Materials And Methods: In this prospective cohort study, 56 adult patients who were receiving maintenance CHD for at least 90 days were assigned to CHD (patients who remained in CHD) and INHD (patients who switched to INHD) groups.

Relationship between changes in blood pressure and left ventricular mass over 1 year in end-stage renal disease.

Objective: The optimal timing of blood pressure (BP) measurement is not firmly established for patients undergoing hemodialysis. We sought to assess which BP measurement change best correlates with changes in left ventricular mass index (LVMI) over 1 year in patients with end-stage renal disease.

Methods: Fifty-seven patients were included in a prospective cohort study comparing the cardiovascular impact of conversion to in-center nocturnal hemodialysis versus continuing conventional hemodialysis.

Relationships Between Left Ventricular Structure and Function According to Cardiac MRI and Cardiac Biomarkers in End-Stage Renal Disease.

Background: We sought to assess the relationships between left ventricular (LV) remodelling and the mechanical and uremic stressors in hemodialysis patients.

Methods: In this prospective 2-centre cohort study, 67 prevalent hemodialysis patients were followed for 1 year. Data on routine bloodwork and predialysis blood pressure (BP) measurements were collected over a 12-week period.

Reduction of carbamylated albumin by extended hemodialysis.

Introduction Among conventional hemodialysis (CHD) patients, carbamylated serum albumin (C-Alb) correlates with urea and amino acid deficiencies and is associated with mortality. We postulated that reduction of C-Alb by intensive HD may correlate with improvements in protein metabolism and cardiac function. Methods One-year observational study of in-center nocturnal extended hemodialysis (EHD) patients and CHD control subjects.

The Association Between Conversion to In-centre Nocturnal Hemodialysis and Left Ventricular Mass Regression in Patients With End-Stage Renal Disease.

Background: In-centre nocturnal hemodialysis (INHD, 7-8 hours/session, 3 times/week) is an increasingly utilized form of dialysis intensification, though data on the cardiovascular benefits of this modality are limited.

Methods: In this prospective cohort study, we enrolled 67 prevalent conventional hemodialysis (CHD, 4 hours/session, 3 times/week) recipients at 2 medical centres in Canada, of whom 37 converted to INHD and 30 remained on CHD. The primary outcome was the change in left ventricular mass (LVM) after 1 year as assessed by cardiac magnetic resonance imaging.

Relationship between different blood pressure measurements and left ventricular mass by cardiac magnetic resonance imaging in end-stage renal disease.

Hypertension is prevalent in patients with end-stage renal disease and is strongly associated with left ventricular hypertrophy (LVH), an independent predictor of cardiovascular mortality. Blood pressure (BP) monitoring in hemodialysis patients may be unreliable because of its lability and variability. We compared different methods of BP measurement and their relationship with LVH on cardiac magnetic resonance imaging.

Correlates of left ventricular mass in chronic hemodialysis recipients.

We aimed to clarify the correlates of left ventricular mass and secondarily, left ventricular volume, in a cohort of prevalent hemodialysis recipients. Left ventricular hypertrophy is common and left ventricular mass is a widely-accepted surrogate for clinical outcomes in dialysis recipients, who are often subjected to chronic pressure and volume overload. However, the precise pathophysiologic mechanisms of left ventricular hypertrophy in this unique population have not been well understood.

Comparative assessment of 2-dimensional echocardiography vs cardiac magnetic resonance imaging in measuring left ventricular mass in patients with and without end-stage renal disease.

Background: While echocardiography (ECHO)-measured left ventricular mass (LVM) predicts adverse cardiovascular events that are common in hemodialysis (HD) recipients, cardiac magnetic resonance imaging (CMR) is now considered the reference standard for determination of LVM. This study aimed to evaluate concordance between LVM measurements across ECHO and CMR among chronic HD recipients and matched controls.

Methods: A single-centre, cross-sectional study of 41 chronic HD patients and 41 matched controls with normal kidney function was performed to compare LVM measurements and left ventricular hypertrophy (LVH) designation by ECHO and CMR.

Supercath Safety Clampcath buttonhole creation: complication of catheter breakage.

The creation of buttonhole tracks with Supercath Safety Clampcath is a novel and simple technique that allows dull fistula needle insertions with relative ease and diminished pain. As greater experience with this procedure develops, new issues arise for consideration. We report an unexpected complication of Supercath Safety Clampcath catheter breakage that may be due to physical distortions as a result of its location in the antecubital fossa just proximal to the elbow joint.

Regression of left ventricular mass following conversion from conventional hemodialysis to thrice weekly in-centre nocturnal hemodialysis.

Background: Increased left ventricular mass (LVM) is associated with adverse outcomes in patients receiving chronic hemodialysis. Among patients receiving conventional hemodialysis (CHD, 3×/week, 4 hrs/session), we evaluated whether dialysis intensification with in-centre nocturnal hemodialysis (INHD, 3×/week, 7-8 hrs/session in the dialysis unit) was associated with regression of LVM.

Methods: We conducted a retrospective cohort study of CHD recipients who converted to INHD and received INHD for at least 6 months.

An examination of the relation between combat experiences and combat-related posttraumatic stress disorder in a sample of Connecticut OEF-OIF Veterans.

Background: Combat exposure is an important risk factor for posttraumatic stress disorder (PTSD). However, little research has examined specific combat experiences associated with PTSD and confirmatory factor analytically (CFA)-derived re-experiencing, avoidance, dysphoria, and hyperarousal symptom clusters.

Methods: A total of 285 predominantly older National Guard/Reservist OEF-OIF Veterans completed an anonymous mail survey that assessed demographics and deployment history, a broad range of combat experiences, PTSD, and unit and postdeployment social support.

Use of the BioHole™ device for the creation of tunnel tracks for buttonhole cannulation of fistula for hemodialysis.

Buttonhole cannulation is a method of cannulation of native arteriovenous fistulae traditionally practiced by self-cannulators. At St Michael's Hospital, this method has been modified to allow its use in problematic fistulae by multiple cannulators. In a busy dialysis unit, the need for a few specific cannulators to establish the tunnel tracks in combination with the variable dialysis schedules creates logistical challenges.

Structure of posttraumatic stress disorder symptoms and psychosocial functioning in Veterans of Operations Enduring Freedom and Iraqi Freedom.

Posttraumatic stress disorder (PTSD) is one of the most prevalent psychiatric conditions in Veterans of Operations Enduring Freedom and Iraqi Freedom (OEF-OIF), but little is known about the structure of PTSD symptoms, and associations between PTSD symptom clusters and psychosocial functioning in this population. A total of 272 OEF-OIF Veterans in Connecticut completed a mail survey containing measures of psychopathology, resilience, and psychosocial functioning. Confirmatory factor analyses revealed that the 4-factor dysphoria model, which is comprised of separate re-experiencing, avoidance, dysphoria, and hyperarousal symptom clusters, provided the best representation of PTSD symptom structure in this sample.

Posttraumatic growth in Veterans of Operations Enduring Freedom and Iraqi Freedom.

Objective: A growing body of research has examined the prevalence and correlates of psychopathology, mild traumatic brain injury, and related problems in Veterans of Operations Enduring Freedom and Iraqi Freedom (OEF-OIF). While these studies help characterize the deleterious effects of combat, no known study has examined factors that may enhance posttraumatic growth or positive changes experienced as a result of combat in this population.

Method: A total of 272 predominantly older Reservist/National Guard OEF-OIF Veterans completed an anonymous mail survey that assessed combat exposure, psychopathology, psychosocial functioning, social support, and posttraumatic growth.