Objective. To determine the period of childhood in which weight relative to height increases in P... more Objective. To determine the period of childhood in which weight relative to height increases in Pima Indian children and young adults in comparison with the general US population. Methods. Heights and weights of children in the Pima Indian population were derived from either clinical examinations conducted by the Department of Public Health Nursing (from 1–48 months of age), or from examinations in the National Institutes of Health longitudinal survey of health in the Pima population (for birth and ages 5–20 years), and compared with standards for the US population recently published by the National Center for Health Statistics. Results. Weight relative to height (weight-for-length in children aged <24 months, body mass index at ages ≥2 years) was significantly higher in Pima children at all ages examined after the first month of life. Compared with reference values, the most dramatic increases in weight relative to height occurred in 2 stages of childhood: mean z scores of weigh...
Clinical Journal of The American Society of Nephrology, Oct 1, 2012
Background and objectives Physicians frequently search bibliographic databases, such as MEDLINE v... more Background and objectives Physicians frequently search bibliographic databases, such as MEDLINE via PubMed, for best evidence for patient care. The objective of this study was to develop and test search filters to help physicians efficiently retrieve literature related to dialysis (hemodialysis or peritoneal dialysis) from all other articles indexed in PubMed, Ovid MEDLINE, and Embase. Design, setting, participants, & measurements A diagnostic test assessment framework was used to develop and test robust dialysis filters. The reference standard was a manual review of the full texts of 22,992 articles from 39 journals to determine whether each article contained dialysis information. Next, 1,623,728 unique search filters were developed, and their ability to retrieve relevant articles was evaluated. Results The high-performance dialysis filters consisted of up to 65 search terms in combination. These terms included the words "dialy" (truncated), "uremic," "catheters," and "renal transplant wait list." These filters reached peak sensitivities of 98.6% and specificities of 98.5%. The filters' performance remained robust in an independent validation subset of articles. Conclusions These empirically derived and validated high-performance search filters should enable physicians to effectively retrieve dialysis information from PubMed, Ovid MEDLINE, and Embase.
It is uncertain whether switching to frequent nocturnal hemodialysis improves cognitive function ... more It is uncertain whether switching to frequent nocturnal hemodialysis improves cognitive function in well-dialyzed patients and how this compares to patients who receive a kidney transplant. We conducted a multicenter observational study with longitudinal follow-up of the effect on cognitive performance of switching dialysis treatment modality from conventional thrice-weekly hemodialysis to frequent nocturnal hemodialysis, a functioning renal transplant or remaining on thrice-weekly conventional hemodialysis. Neuropsychological tests of memory, attention, psychomotor processing speed, executive function and fluency as well as measures of solute clearance were performed at baseline and again after switching modality. The change in cognitive performance measured by neuropsychological tests assessing multiple cognitive domains at baseline, 4 and 12 months after switching dialysis modality were analyzed using a linear mixed model. Seventy-seven patients were enrolled; 21 of these 77 pati...
The objectives of this thesis are to emphasise the importance of extraneous blood loss to the pat... more The objectives of this thesis are to emphasise the importance of extraneous blood loss to the patient receiving maintenance haemodialysis; to demonstrate the source and magnitude of this blood loss; to define the blood loss caused by some commonly used haemodialysers; and to explore the reasons why blood should remain trapped within them. The anaemia of chronic renal failure is seldom corrected by regular dialysis treatment and may be augmented and complicated by the development of folic acid deficiency, iron deficiency, and considerable blood losses. This anaemia is usually associated with a normochromic, normocytic blood film and is basically due to a decreased rate of erythropoiesis associated with the incomplete correction of the-uraemic syndrome afforded by haemodialysis. Androgen and cobalt therapy have been advocated as a means of increasing the rate of erythropoiesis but results have not been universally satisfactory. Folic acid deficiency is easily dealt with by oral supple...
Introduction and objectives: In thrice weekly conventional hemodialysis, dialysate sodium prescri... more Introduction and objectives: In thrice weekly conventional hemodialysis, dialysate sodium prescription can cause intradialytic plasma sodium shifts, and undesirable symptoms. However, changes in pre-dialysis plasma sodium setpoint are not observed. Whether these clinical observations are observed in quotidian or nocturnal home hemodialysis has not been prospectively evaluated. Methods: A randomized crossover study of conventional, quotidian and nocturnal home hemodialysis patients was performed. Dialysate sodium was personalized 3 mmol/L above (HIGHDIALSOD) or below (LOWDialSOD) the SP, with 100 days for each crossover studies period. Results: Plasma Na + decreased during hemodialysis in LOWDialSOD study period (136.8 to 135.0 mmol/L, p=0.002). Pre-Na + SP (137.4 to 136.8 mmol/L, p=0.03) and Pre-Na + SP slope (0.014 to-0.015 mmol/L/day, p=0.009) decreased from HIGHDialSOD to LOWDialSOD study periods. Conclusions: Personalization of Dial-Na + to below SP leads to reductions in plasma sodium concentration during hemodialysis, in conventional, quotidian and nocturnal home hemodialysis patients. Furthermore, sodium set point changes in response to Dial-Na + prescription. This has the potential to lead to adverse outcomes in a patient population that is followed less frequently and stringently than the in-center hemodialysis population.
Journal of Clinical & Experimental Nephrology, 2017
Background: In thrice weekly conventional haemodialysis patients, higher dialysate sodium concent... more Background: In thrice weekly conventional haemodialysis patients, higher dialysate sodium concentrations may associate with adverse clinical outcomes. Whether increased frequency and duration of haemodialysis in quotidian and nocturnal patients alters these clinical outcomes is unknown. Methods: A randomized crossover study was performed in conventional, quotidian and nocturnal haemodialysis patients. Dialysate sodium (Dial-Na +) was personalized 3 mmol/L above (DIALHighSOD) or below (DIALLowSOD) the pre-dialysis plasma sodium set point (SP), with 100 days for each crossover study period. Results: Interdialytic weight gain (IDWG)(2.15 vs. 1.90 L, p=0.002), IDWG as % of target weight (IDWG%)(2.78 vs. 2.39%, p=0.002), pre-dialysis systolic (143.3 vs. 138.3 mm Hg, p=0.001), diastolic (78.6 vs. 75.6 mm Hg, p=0.008) and mean arterial pressure (100.2 vs. 96.5 mm Hg, p=0.003), post-dialysis systolic (135.4 vs. 130.0 mm Hg, p=0.04), diastolic (75.8 vs. 72.4 mm Hg, p=0.006) and mean arterial pressure (95.7 vs. 91.6 mm Hg, p=0.009) were higher in DIALHighSOD than DIALLowSOD. Haemodialysis frequency was associated with decreased (R=-0.295, slope=-0.002, p=0.034) IDWG%, while the opposite was seen with haemodialysis duration (R=0.507, slope=0.002, p<0.001). Haemodialysis duration increased intradialytic change in diastolic blood pressure (R=0.280, slope=1.127, p=0.044), while haemodialysis frequency increased post-dialysis diastolic blood pressure (R=0.366, slope=3.464, p=0.008). Conclusions: These results confirm that dialysate sodium concentration alters clinical outcomes in quotidian and nocturnal haemodialysis patients, and that dialysis frequency and duration correlate in opposing fashions in IDWG. Further studies are required to determine the effect of dialysate sodium on cardiovascular outcomes. This trial is registered at UMIN000026102.
Introduction: The Frequent Hemodialysis Network (FHN) Daily and Nocturnal trials aimed to compare... more Introduction: The Frequent Hemodialysis Network (FHN) Daily and Nocturnal trials aimed to compare the effects of hemodialysis (HD) given 6 versus 3 times per week. More frequent in-center HD significantly reduced left-ventricular mass (LVM), with more pronounced effects in patients with low urine volumes. In this study, we aimed to explore another potential effect modifier: the predialysis serum sodium (SNa) and related proxies of plasma tonicity. Methods: Using data from the FHN Daily and Nocturnal Trials, we compared the effects of frequent HD on LVM among patients stratified by SNa, dialysate-to-predialysis serum-sodium gradient (GNa), systolic and diastolic blood pressure, time-integrated sodium-adjusted fluid load (TIFL), and extracellular fluid volume estimated by bioelectrical impedance analysis. Results: In 197 enrolled subjects in the FHN Daily Trial, the treatment effect of frequent HD on ∆LVM was modified by SNa. When the FHN Daily Trial participants are divided into lowe...
Pediatric nephrology (Berlin, Germany), Dec 19, 2016
Although measuring creatinine to determine kidney function is currently the clinical standard, ne... more Although measuring creatinine to determine kidney function is currently the clinical standard, new markers such as beta-trace protein (BTP) and beta-2-microglobulin (B2M) are being investigated in an effort to measure glomerular filtration rate more accurately. In their recent publication, Inker et al. (Am J Kidney Dis 2015; 67:40-48) explored the use of these two relatively new markers in combination with some commonly available clinical characteristics in a large cohort of adults with chronic kidney disease. Their research led them to develop three formulae using BTP, B2M, and a combination of the two. The combined formula is particularly attractive as it removes all gender bias, which applies to both serum creatinine and cystatin C. Using data from a cohort of 127 pediatric patients from our center, we sought to determine whether these formulae would be equally as effective in children as in adults. Unfortunately, we found that the formulae cannot be applied to the pediatric popu...
Canadian Medical Association journal, Jan 10, 1978
Twenty patients with nephritis due to systemic lupus erythematosus were followed up for a mean of... more Twenty patients with nephritis due to systemic lupus erythematosus were followed up for a mean of 34 months after renal biopsy with serial determinations of total serum complement and C3 and C4 concentrations, binding of deoxyribonucleic acid (DNA), antinuclear antibody pattern and platelet count. There were 25 episodes of nonhematologic observed disease activity in 16 of the 20 patients; elevated DNA binding and thrombocytopenia correlated well with these episodes. The mean platelet count during episodes of observed disease activity was 96 +/- 42 X 10(9)/L, which was significantly different from the mean count of 248 +/- 90 X 10(9)/L during disease quiescence. The proportion of false-positive results with the immunologic tests varied from 25% to 67% and with platelet counts it was 11%. It is suggested that thrombocytopenia may be a simple and accurate index of disease activity in lupus nephritis.
Canadian Medical Association journal, Jan 15, 1981
Twelve patients with systemic lupus erythematosus and biopsy-proved diffuse proliferative glomeru... more Twelve patients with systemic lupus erythematosus and biopsy-proved diffuse proliferative glomerulonephritis were randomly allocated to a control group (to continue receiving conventional therapy only) or to a plasmapheresis group (to receive conventional therapy along with one 4-I plasma exchange a month). The six patients treated with plasmapheresis had better preservation of renal function, reduced disease activity, fewer admissions to hospital and less need for steroid and immunosuppressive therapy than the six control patients. The patients treated with plasmapheresis also showed evidence of reduced immunologic activity and had no side effects attributable to the plasma exchange. These results suggest that monthly plasma exchange should be assessed in a controlled randomized trial as a possible therapeutic adjunct in patients with systemic lupus erythematosus and diffuse proliferative glomerulonephritis.
Establishing the effect of fluctuating extracellular fluid (ECF) volume on muscle strength in peo... more Establishing the effect of fluctuating extracellular fluid (ECF) volume on muscle strength in people with end-stage renal disease (ESRD) on hemodialysis (HD) is essential, as inadequate hydration of the skeletal muscles impacts its strength and endurance. Bioelectrical impedance spectroscopy (BIS) has been a widely used method for estimating ECF volume of a limb or calf segment. Magnetic resonance imaging (MRI)-acquired transverse relaxation times (T2) has also been used for estimating ECF volumes of individual skeletal muscles. The purpose of this study was to determine the association between T2 (gold standard) of tibialis anterior (TA), medial (MG), and lateral gastrocnemius (LG), and soleus muscles and calf BIS ECF, in healthy and in people with ESRD/HD. Calf BIS and MRI measures were collected on two occasions before and after HD session in people with ESRD/HD and on a single occasion for the healthy participants. Linear regression analysis was used to establish the association...
Purpose. The purpose of this study was to investigate the test-retest reliability, relative varia... more Purpose. The purpose of this study was to investigate the test-retest reliability, relative variability, and agreement between calf bioelectrical impedance-spectroscopy (cBIS) acquired extracellular fluid (ECF), intracellular fluid (ICF), total water and the ratio of ECF : ICF, magnetic-resonance-imaging (MRI) acquired transverse relaxation times (T2), and apparent diffusion coefficient (ADC) of calf muscles of the same segment in healthy individuals. Methods. Muscle hydration measures were collected in 32 healthy individuals on two occasions and analyzed by a single rater. On both occasions, MRI measures were collected from tibialis anterior (TA), medial (MG), and lateral gastrocnemius (LG) and soleus muscles following the cBIS data acquired using XiTRON Hydra 4200 BIS device. The intraclass correlation coefficients (ICC2,1), coefficient of variation (CV), and agreement between MRI and cBIS data were also calculated. Results. ICC2,1 values for cBIS, T2, and ADC ranged from 0.56 to ...
Journal of the American Society of Nephrology, 2005
Complications related to inadequate volume management are common during hemodialysis. This trial ... more Complications related to inadequate volume management are common during hemodialysis. This trial tested the hypothesis that availability of an intradialytic blood volume monitoring (IBVM) device improves fluid removal, reducing morbidity. A six-center, randomized trial with 6 mo of intervention comparing IBVM using Crit-Line versus conventional clinical monitoring was conducted. The average rate of non-access-related hospitalizations was compared across treatment groups using Poisson regression. Mortality analysis used the Kaplan Meier method. A total of 227 patients were randomized to Crit-Line, and 216 were randomized to conventional monitoring. Both groups had similar baseline characteristics. During the study, no differences in weight, BP, or number of dialysis-related complications were observed. There were 120 and 81 non-access-related hospitalizations in the Crit-Line and conventional monitoring groups. The adjusted risk ratio for non-access-related and access-related hospitalization was 1.61 (95% confidence interval 1.15 to 2.25; P ؍ 0.01) and 1.52 (95% confidence interval 1.02 to 2.28; P ؍ 0.04) for the Crit-Line monitoring group. Mortality was 8.7% in the Crit-Line monitoring group and 3.3% in the conventional group (P ؍ 0.021). Standardized mortality ratios comparing the Crit-Line and conventional monitoring groups to the prevalent hemodialysis population were 0.77 (NS) and 0.26 (P < 0.001). Hospitalization rates were 1.51 and 1.03 events/yr in the Crit-Line and standard monitoring groups, compared with 2.01 for the prevalent hemodialysis population. IBVM was associated with higher nonvascular and vascular access-related hospitalizations and mortality compared with conventional monitoring. The atypically low hospitalization and mortality rates for the conventional monitoring group suggest that these findings should be generalized to the US hemodialysis population with caution.
Journal of Neurology, Neurosurgery & Psychiatry, 1979
A bovine shunt, inserted between the radial artery and cephalic vein in the upper arm for access ... more A bovine shunt, inserted between the radial artery and cephalic vein in the upper arm for access during chronic haemodialysis, caused a distal, ischaemic neuropathy in two patients. There were electrophysiological signs of axonal degeneration of motor and sensory nerve fibres in the patient with severe ischaemia, and, of only sensory fibres in the patient with mild ischaemia. Thenar muscle blood flow studies using 133Xe were a useful measure of altered tissue perfusion. Recovery was incomplete in improved tissue perfusion in the severe case.
Clinical Journal of the American Society of Nephrology, 2009
Background and objectives: Shorter travel times and distance to dialysis clinics have been associ... more Background and objectives: Shorter travel times and distance to dialysis clinics have been associated with improved patient outcomes and a higher health-related quality of life (HRQOL). The objective of this study was to compare HRQOL between prevalent in-center and satellite dialysis patients, as well as compare travel-related factors that contribute to HRQOL between in-center and satellite-based patients. Design, setting, participants, & measures: The London Health Sciences Centre is a tertiary care center with in-center and regional satellite hemodialysis units. Patients who consented and completed a questionnaire (n ؍ 202) were enrolled into a cross-sectional, cohort observational study. Patients were administered the Medical Outcomes Short-Form 36 (SF-36) and the Kidney Disease Health Related Quality of Life (KDHRQOL) tool and were asked questions relating to travel to dialysis clinics. Results: Patients who underwent dialysis in the satellites had similar demographics, comorbidities, and laboratory parameters. Patients who underwent dialysis in satellite units reported a significantly superior score on the dialysis stress domain of the KDHRQOL questionnaire. There was no significant difference between in-center and satellite patients on the basis of the SF-36. Satellite patients also reported a significantly decreased cost of transportation, a significantly increased proportion who drive themselves to clinics, and significantly decreased travel time. Conclusions: Patients who underwent dialysis in satellite units demonstrated similar characteristics, comorbidities, surrogate outcomes, and most aspects of HRQOL. Travel time, cost, and receiving treatment in one's own community are important factors that may contribute to a trend toward higher reported HRQOL by patients in satellite dialysis units.
Clinical Journal of the American Society of Nephrology, 2010
Summary Background and objectives Surrogate markers such as creatinine, cystatin C (CysC), and be... more Summary Background and objectives Surrogate markers such as creatinine, cystatin C (CysC), and beta trace protein (BTP) have been used to estimate GFR (eGFR). The accuracy of eGFR may be altered with hyperfiltration and differences in filtration fraction (FF). It is hypothesized that the accuracy of creatinine for eGFR may be affected by hyperfiltration and different effective renal plasma flow (ERPF). Design, setting, participants, & measurements A total of 127 pediatric patients with various renal diseases underwent simultaneous measurements of GFR using 51Cr-EDTA renal scan and ERPF (131I-hippurate clearance) to calculate the FF (FF = GFR/ERPF). The eGFRs were calculated using the commonly used Schwartz (creatinine), Filler (CysC), and Benlamri (BTP) formulas. Agreement of the eGFRs with the measured isotope GFRs was assessed by Bland–Altman plots. Correlation analysis was performed using nonparametric tests to compare FF with eGFR − GFR. Results The 127 children at a median age ...
Fifty-five dialyses were performed using the EX-03 dialyser cartridge. The performance of the dia... more Fifty-five dialyses were performed using the EX-03 dialyser cartridge. The performance of the dialyser In respect of urea, creatinine, phosphate, and uric acid dialysance is comparable to that of the Travenol Ultra-Flo 100 (cuprophane). It is rather more compact, is easy to operate, has minimal blood loss, and a low primig volume. Ultrafiltration was quite adequate and the dialyses were uncomplicated by side effects. A failure rate of 7% occurred but none of the patients lost any appreciable quantity of blood.
Objective. To determine the period of childhood in which weight relative to height increases in P... more Objective. To determine the period of childhood in which weight relative to height increases in Pima Indian children and young adults in comparison with the general US population. Methods. Heights and weights of children in the Pima Indian population were derived from either clinical examinations conducted by the Department of Public Health Nursing (from 1–48 months of age), or from examinations in the National Institutes of Health longitudinal survey of health in the Pima population (for birth and ages 5–20 years), and compared with standards for the US population recently published by the National Center for Health Statistics. Results. Weight relative to height (weight-for-length in children aged <24 months, body mass index at ages ≥2 years) was significantly higher in Pima children at all ages examined after the first month of life. Compared with reference values, the most dramatic increases in weight relative to height occurred in 2 stages of childhood: mean z scores of weigh...
Clinical Journal of The American Society of Nephrology, Oct 1, 2012
Background and objectives Physicians frequently search bibliographic databases, such as MEDLINE v... more Background and objectives Physicians frequently search bibliographic databases, such as MEDLINE via PubMed, for best evidence for patient care. The objective of this study was to develop and test search filters to help physicians efficiently retrieve literature related to dialysis (hemodialysis or peritoneal dialysis) from all other articles indexed in PubMed, Ovid MEDLINE, and Embase. Design, setting, participants, & measurements A diagnostic test assessment framework was used to develop and test robust dialysis filters. The reference standard was a manual review of the full texts of 22,992 articles from 39 journals to determine whether each article contained dialysis information. Next, 1,623,728 unique search filters were developed, and their ability to retrieve relevant articles was evaluated. Results The high-performance dialysis filters consisted of up to 65 search terms in combination. These terms included the words "dialy" (truncated), "uremic," "catheters," and "renal transplant wait list." These filters reached peak sensitivities of 98.6% and specificities of 98.5%. The filters' performance remained robust in an independent validation subset of articles. Conclusions These empirically derived and validated high-performance search filters should enable physicians to effectively retrieve dialysis information from PubMed, Ovid MEDLINE, and Embase.
It is uncertain whether switching to frequent nocturnal hemodialysis improves cognitive function ... more It is uncertain whether switching to frequent nocturnal hemodialysis improves cognitive function in well-dialyzed patients and how this compares to patients who receive a kidney transplant. We conducted a multicenter observational study with longitudinal follow-up of the effect on cognitive performance of switching dialysis treatment modality from conventional thrice-weekly hemodialysis to frequent nocturnal hemodialysis, a functioning renal transplant or remaining on thrice-weekly conventional hemodialysis. Neuropsychological tests of memory, attention, psychomotor processing speed, executive function and fluency as well as measures of solute clearance were performed at baseline and again after switching modality. The change in cognitive performance measured by neuropsychological tests assessing multiple cognitive domains at baseline, 4 and 12 months after switching dialysis modality were analyzed using a linear mixed model. Seventy-seven patients were enrolled; 21 of these 77 pati...
The objectives of this thesis are to emphasise the importance of extraneous blood loss to the pat... more The objectives of this thesis are to emphasise the importance of extraneous blood loss to the patient receiving maintenance haemodialysis; to demonstrate the source and magnitude of this blood loss; to define the blood loss caused by some commonly used haemodialysers; and to explore the reasons why blood should remain trapped within them. The anaemia of chronic renal failure is seldom corrected by regular dialysis treatment and may be augmented and complicated by the development of folic acid deficiency, iron deficiency, and considerable blood losses. This anaemia is usually associated with a normochromic, normocytic blood film and is basically due to a decreased rate of erythropoiesis associated with the incomplete correction of the-uraemic syndrome afforded by haemodialysis. Androgen and cobalt therapy have been advocated as a means of increasing the rate of erythropoiesis but results have not been universally satisfactory. Folic acid deficiency is easily dealt with by oral supple...
Introduction and objectives: In thrice weekly conventional hemodialysis, dialysate sodium prescri... more Introduction and objectives: In thrice weekly conventional hemodialysis, dialysate sodium prescription can cause intradialytic plasma sodium shifts, and undesirable symptoms. However, changes in pre-dialysis plasma sodium setpoint are not observed. Whether these clinical observations are observed in quotidian or nocturnal home hemodialysis has not been prospectively evaluated. Methods: A randomized crossover study of conventional, quotidian and nocturnal home hemodialysis patients was performed. Dialysate sodium was personalized 3 mmol/L above (HIGHDIALSOD) or below (LOWDialSOD) the SP, with 100 days for each crossover studies period. Results: Plasma Na + decreased during hemodialysis in LOWDialSOD study period (136.8 to 135.0 mmol/L, p=0.002). Pre-Na + SP (137.4 to 136.8 mmol/L, p=0.03) and Pre-Na + SP slope (0.014 to-0.015 mmol/L/day, p=0.009) decreased from HIGHDialSOD to LOWDialSOD study periods. Conclusions: Personalization of Dial-Na + to below SP leads to reductions in plasma sodium concentration during hemodialysis, in conventional, quotidian and nocturnal home hemodialysis patients. Furthermore, sodium set point changes in response to Dial-Na + prescription. This has the potential to lead to adverse outcomes in a patient population that is followed less frequently and stringently than the in-center hemodialysis population.
Journal of Clinical & Experimental Nephrology, 2017
Background: In thrice weekly conventional haemodialysis patients, higher dialysate sodium concent... more Background: In thrice weekly conventional haemodialysis patients, higher dialysate sodium concentrations may associate with adverse clinical outcomes. Whether increased frequency and duration of haemodialysis in quotidian and nocturnal patients alters these clinical outcomes is unknown. Methods: A randomized crossover study was performed in conventional, quotidian and nocturnal haemodialysis patients. Dialysate sodium (Dial-Na +) was personalized 3 mmol/L above (DIALHighSOD) or below (DIALLowSOD) the pre-dialysis plasma sodium set point (SP), with 100 days for each crossover study period. Results: Interdialytic weight gain (IDWG)(2.15 vs. 1.90 L, p=0.002), IDWG as % of target weight (IDWG%)(2.78 vs. 2.39%, p=0.002), pre-dialysis systolic (143.3 vs. 138.3 mm Hg, p=0.001), diastolic (78.6 vs. 75.6 mm Hg, p=0.008) and mean arterial pressure (100.2 vs. 96.5 mm Hg, p=0.003), post-dialysis systolic (135.4 vs. 130.0 mm Hg, p=0.04), diastolic (75.8 vs. 72.4 mm Hg, p=0.006) and mean arterial pressure (95.7 vs. 91.6 mm Hg, p=0.009) were higher in DIALHighSOD than DIALLowSOD. Haemodialysis frequency was associated with decreased (R=-0.295, slope=-0.002, p=0.034) IDWG%, while the opposite was seen with haemodialysis duration (R=0.507, slope=0.002, p<0.001). Haemodialysis duration increased intradialytic change in diastolic blood pressure (R=0.280, slope=1.127, p=0.044), while haemodialysis frequency increased post-dialysis diastolic blood pressure (R=0.366, slope=3.464, p=0.008). Conclusions: These results confirm that dialysate sodium concentration alters clinical outcomes in quotidian and nocturnal haemodialysis patients, and that dialysis frequency and duration correlate in opposing fashions in IDWG. Further studies are required to determine the effect of dialysate sodium on cardiovascular outcomes. This trial is registered at UMIN000026102.
Introduction: The Frequent Hemodialysis Network (FHN) Daily and Nocturnal trials aimed to compare... more Introduction: The Frequent Hemodialysis Network (FHN) Daily and Nocturnal trials aimed to compare the effects of hemodialysis (HD) given 6 versus 3 times per week. More frequent in-center HD significantly reduced left-ventricular mass (LVM), with more pronounced effects in patients with low urine volumes. In this study, we aimed to explore another potential effect modifier: the predialysis serum sodium (SNa) and related proxies of plasma tonicity. Methods: Using data from the FHN Daily and Nocturnal Trials, we compared the effects of frequent HD on LVM among patients stratified by SNa, dialysate-to-predialysis serum-sodium gradient (GNa), systolic and diastolic blood pressure, time-integrated sodium-adjusted fluid load (TIFL), and extracellular fluid volume estimated by bioelectrical impedance analysis. Results: In 197 enrolled subjects in the FHN Daily Trial, the treatment effect of frequent HD on ∆LVM was modified by SNa. When the FHN Daily Trial participants are divided into lowe...
Pediatric nephrology (Berlin, Germany), Dec 19, 2016
Although measuring creatinine to determine kidney function is currently the clinical standard, ne... more Although measuring creatinine to determine kidney function is currently the clinical standard, new markers such as beta-trace protein (BTP) and beta-2-microglobulin (B2M) are being investigated in an effort to measure glomerular filtration rate more accurately. In their recent publication, Inker et al. (Am J Kidney Dis 2015; 67:40-48) explored the use of these two relatively new markers in combination with some commonly available clinical characteristics in a large cohort of adults with chronic kidney disease. Their research led them to develop three formulae using BTP, B2M, and a combination of the two. The combined formula is particularly attractive as it removes all gender bias, which applies to both serum creatinine and cystatin C. Using data from a cohort of 127 pediatric patients from our center, we sought to determine whether these formulae would be equally as effective in children as in adults. Unfortunately, we found that the formulae cannot be applied to the pediatric popu...
Canadian Medical Association journal, Jan 10, 1978
Twenty patients with nephritis due to systemic lupus erythematosus were followed up for a mean of... more Twenty patients with nephritis due to systemic lupus erythematosus were followed up for a mean of 34 months after renal biopsy with serial determinations of total serum complement and C3 and C4 concentrations, binding of deoxyribonucleic acid (DNA), antinuclear antibody pattern and platelet count. There were 25 episodes of nonhematologic observed disease activity in 16 of the 20 patients; elevated DNA binding and thrombocytopenia correlated well with these episodes. The mean platelet count during episodes of observed disease activity was 96 +/- 42 X 10(9)/L, which was significantly different from the mean count of 248 +/- 90 X 10(9)/L during disease quiescence. The proportion of false-positive results with the immunologic tests varied from 25% to 67% and with platelet counts it was 11%. It is suggested that thrombocytopenia may be a simple and accurate index of disease activity in lupus nephritis.
Canadian Medical Association journal, Jan 15, 1981
Twelve patients with systemic lupus erythematosus and biopsy-proved diffuse proliferative glomeru... more Twelve patients with systemic lupus erythematosus and biopsy-proved diffuse proliferative glomerulonephritis were randomly allocated to a control group (to continue receiving conventional therapy only) or to a plasmapheresis group (to receive conventional therapy along with one 4-I plasma exchange a month). The six patients treated with plasmapheresis had better preservation of renal function, reduced disease activity, fewer admissions to hospital and less need for steroid and immunosuppressive therapy than the six control patients. The patients treated with plasmapheresis also showed evidence of reduced immunologic activity and had no side effects attributable to the plasma exchange. These results suggest that monthly plasma exchange should be assessed in a controlled randomized trial as a possible therapeutic adjunct in patients with systemic lupus erythematosus and diffuse proliferative glomerulonephritis.
Establishing the effect of fluctuating extracellular fluid (ECF) volume on muscle strength in peo... more Establishing the effect of fluctuating extracellular fluid (ECF) volume on muscle strength in people with end-stage renal disease (ESRD) on hemodialysis (HD) is essential, as inadequate hydration of the skeletal muscles impacts its strength and endurance. Bioelectrical impedance spectroscopy (BIS) has been a widely used method for estimating ECF volume of a limb or calf segment. Magnetic resonance imaging (MRI)-acquired transverse relaxation times (T2) has also been used for estimating ECF volumes of individual skeletal muscles. The purpose of this study was to determine the association between T2 (gold standard) of tibialis anterior (TA), medial (MG), and lateral gastrocnemius (LG), and soleus muscles and calf BIS ECF, in healthy and in people with ESRD/HD. Calf BIS and MRI measures were collected on two occasions before and after HD session in people with ESRD/HD and on a single occasion for the healthy participants. Linear regression analysis was used to establish the association...
Purpose. The purpose of this study was to investigate the test-retest reliability, relative varia... more Purpose. The purpose of this study was to investigate the test-retest reliability, relative variability, and agreement between calf bioelectrical impedance-spectroscopy (cBIS) acquired extracellular fluid (ECF), intracellular fluid (ICF), total water and the ratio of ECF : ICF, magnetic-resonance-imaging (MRI) acquired transverse relaxation times (T2), and apparent diffusion coefficient (ADC) of calf muscles of the same segment in healthy individuals. Methods. Muscle hydration measures were collected in 32 healthy individuals on two occasions and analyzed by a single rater. On both occasions, MRI measures were collected from tibialis anterior (TA), medial (MG), and lateral gastrocnemius (LG) and soleus muscles following the cBIS data acquired using XiTRON Hydra 4200 BIS device. The intraclass correlation coefficients (ICC2,1), coefficient of variation (CV), and agreement between MRI and cBIS data were also calculated. Results. ICC2,1 values for cBIS, T2, and ADC ranged from 0.56 to ...
Journal of the American Society of Nephrology, 2005
Complications related to inadequate volume management are common during hemodialysis. This trial ... more Complications related to inadequate volume management are common during hemodialysis. This trial tested the hypothesis that availability of an intradialytic blood volume monitoring (IBVM) device improves fluid removal, reducing morbidity. A six-center, randomized trial with 6 mo of intervention comparing IBVM using Crit-Line versus conventional clinical monitoring was conducted. The average rate of non-access-related hospitalizations was compared across treatment groups using Poisson regression. Mortality analysis used the Kaplan Meier method. A total of 227 patients were randomized to Crit-Line, and 216 were randomized to conventional monitoring. Both groups had similar baseline characteristics. During the study, no differences in weight, BP, or number of dialysis-related complications were observed. There were 120 and 81 non-access-related hospitalizations in the Crit-Line and conventional monitoring groups. The adjusted risk ratio for non-access-related and access-related hospitalization was 1.61 (95% confidence interval 1.15 to 2.25; P ؍ 0.01) and 1.52 (95% confidence interval 1.02 to 2.28; P ؍ 0.04) for the Crit-Line monitoring group. Mortality was 8.7% in the Crit-Line monitoring group and 3.3% in the conventional group (P ؍ 0.021). Standardized mortality ratios comparing the Crit-Line and conventional monitoring groups to the prevalent hemodialysis population were 0.77 (NS) and 0.26 (P < 0.001). Hospitalization rates were 1.51 and 1.03 events/yr in the Crit-Line and standard monitoring groups, compared with 2.01 for the prevalent hemodialysis population. IBVM was associated with higher nonvascular and vascular access-related hospitalizations and mortality compared with conventional monitoring. The atypically low hospitalization and mortality rates for the conventional monitoring group suggest that these findings should be generalized to the US hemodialysis population with caution.
Journal of Neurology, Neurosurgery & Psychiatry, 1979
A bovine shunt, inserted between the radial artery and cephalic vein in the upper arm for access ... more A bovine shunt, inserted between the radial artery and cephalic vein in the upper arm for access during chronic haemodialysis, caused a distal, ischaemic neuropathy in two patients. There were electrophysiological signs of axonal degeneration of motor and sensory nerve fibres in the patient with severe ischaemia, and, of only sensory fibres in the patient with mild ischaemia. Thenar muscle blood flow studies using 133Xe were a useful measure of altered tissue perfusion. Recovery was incomplete in improved tissue perfusion in the severe case.
Clinical Journal of the American Society of Nephrology, 2009
Background and objectives: Shorter travel times and distance to dialysis clinics have been associ... more Background and objectives: Shorter travel times and distance to dialysis clinics have been associated with improved patient outcomes and a higher health-related quality of life (HRQOL). The objective of this study was to compare HRQOL between prevalent in-center and satellite dialysis patients, as well as compare travel-related factors that contribute to HRQOL between in-center and satellite-based patients. Design, setting, participants, & measures: The London Health Sciences Centre is a tertiary care center with in-center and regional satellite hemodialysis units. Patients who consented and completed a questionnaire (n ؍ 202) were enrolled into a cross-sectional, cohort observational study. Patients were administered the Medical Outcomes Short-Form 36 (SF-36) and the Kidney Disease Health Related Quality of Life (KDHRQOL) tool and were asked questions relating to travel to dialysis clinics. Results: Patients who underwent dialysis in the satellites had similar demographics, comorbidities, and laboratory parameters. Patients who underwent dialysis in satellite units reported a significantly superior score on the dialysis stress domain of the KDHRQOL questionnaire. There was no significant difference between in-center and satellite patients on the basis of the SF-36. Satellite patients also reported a significantly decreased cost of transportation, a significantly increased proportion who drive themselves to clinics, and significantly decreased travel time. Conclusions: Patients who underwent dialysis in satellite units demonstrated similar characteristics, comorbidities, surrogate outcomes, and most aspects of HRQOL. Travel time, cost, and receiving treatment in one's own community are important factors that may contribute to a trend toward higher reported HRQOL by patients in satellite dialysis units.
Clinical Journal of the American Society of Nephrology, 2010
Summary Background and objectives Surrogate markers such as creatinine, cystatin C (CysC), and be... more Summary Background and objectives Surrogate markers such as creatinine, cystatin C (CysC), and beta trace protein (BTP) have been used to estimate GFR (eGFR). The accuracy of eGFR may be altered with hyperfiltration and differences in filtration fraction (FF). It is hypothesized that the accuracy of creatinine for eGFR may be affected by hyperfiltration and different effective renal plasma flow (ERPF). Design, setting, participants, & measurements A total of 127 pediatric patients with various renal diseases underwent simultaneous measurements of GFR using 51Cr-EDTA renal scan and ERPF (131I-hippurate clearance) to calculate the FF (FF = GFR/ERPF). The eGFRs were calculated using the commonly used Schwartz (creatinine), Filler (CysC), and Benlamri (BTP) formulas. Agreement of the eGFRs with the measured isotope GFRs was assessed by Bland–Altman plots. Correlation analysis was performed using nonparametric tests to compare FF with eGFR − GFR. Results The 127 children at a median age ...
Fifty-five dialyses were performed using the EX-03 dialyser cartridge. The performance of the dia... more Fifty-five dialyses were performed using the EX-03 dialyser cartridge. The performance of the dialyser In respect of urea, creatinine, phosphate, and uric acid dialysance is comparable to that of the Travenol Ultra-Flo 100 (cuprophane). It is rather more compact, is easy to operate, has minimal blood loss, and a low primig volume. Ultrafiltration was quite adequate and the dialyses were uncomplicated by side effects. A failure rate of 7% occurred but none of the patients lost any appreciable quantity of blood.
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Papers by Robert Lindsay