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Robert M Lindsay

Publications and source records attributed to Robert M Lindsay.

At least 19 recordsLinked to original sources

The International Quotidian Dialysis Registry: annual report 2006.

Interest in short daily and nocturnal hemodialysis (HD) regimens continues to grow worldwide. Despite growing optimism that these therapies will afford better patient outcomes over conventional HD, the current literature has not been viewed as sufficiently compelling to affect widespread implementation in most jurisdictions. Before these therapies can gain wider acceptance, larger and more rigorous studies will likely be needed. In June 2004, the Quotidian Dialysis Registry, based at the Lawson Health Research Institute at the University of Western Ontario, Canada, began recruiting patients across North America. By using an Internet-based data entry platform, patients from various centers worldwide will eventually be recruited, and studied prospectively. This paper constitutes the second annual update on patient and center recruitment, patient and treatment characteristics, and future directions for the registry.

Adult↗

Intradialytic blood volume monitoring in ambulatory hemodialysis patients: a randomized trial.

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.

Adult↗

Dialyzer reactions in a patient switching from peritoneal dialysis to hemodialysis.

Many terms have been used to describe the collection of signs and symptoms triggered by the initial use of dialyzers. These reactions can be divided into Type A (hypersensitivity reactions, with the incidence of 4/100,000) and Type B (nonspecific reactions, incidence 3-5/100). Many different mechanisms have been postulated, including complement activation, pulmonary leukostasis, hypersensitivity to ethylene oxide, interaction between the AN69 membrane and angiotensin-converting enzyme inhibitors, and dialysate contamination. An unusual case of dialyzer reactions is presented here, involving a patient who had to discontinue peritoneal dialysis when she was admitted with fungal peritonitis. Upon initiation of hemodialysis, she experienced dyspnea and burning sensation and demonstrated significant leukopenia, thrombocytopenia, and oxygen desaturation. These reactions persisted despite double-rinsing of the dialyzers and the use of several different dialyzers with synthetic membranes (polysulfone and AN69), and a variety of sterilization methods (electron beam and gamma radiation). In the end, a simple measure was found to be effective in preventing further dialyzer reactions in this fascinating case.

Aged↗

The International Quotidian Dialysis Registry: annual report 2005.

The International Quotidian Dialysis Registry was designed to collect data describing treatments, characteristics, and outcomes of patients treated with quotidian hemodialysis (HD) worldwide. In July 2004, North American centers were first invited to enroll patients. By March 1, 2005, a total of 70 nocturnal and 8 short-daily HD patients from three Canadian and two US centers were enrolled. As recruitment continues, projected enrollment for 2005 may exceed 200 patients from North America alone. Preliminary analyses indicate that the current registry cohort is younger (mean age, 49.5 +/- 1.6 years) and carries a lower burden of comorbidity than the overall North American HD population. The low event rate expected in this cohort underlines the need for a large sample size if an appropriately powered survival study is to be undertaken. Increasing recruitment in the United States by including HD centers owned or managed by large dialysis organizations, and beginning overseas collaborations to include Australia, New Zealand, Europe, and South America will be the primary areas of focus for 2005.

Adolescent↗

Arteriovenous fistula-associated high-output cardiac failure: a review of mechanisms.

High-output cardiac failure can be a rare complication of high-output arteriovenous fistula. The authors present a case in which a hemodialysis patient with a high-flow arteriovenous fistula has cardiac failure that improves with fistula closure. The hemodynamic effects of a fistula are reviewed, and the hemodialysis literature regarding high-output cardiac failure is summarized. To gain insight into the problem of high-output cardiac failure, research efforts should focus on the prospective monitoring of high-access flows.

Aged↗

Is more frequent hemodialysis beneficial and what is the evidence?

PURPOSE OF REVIEW: The HEMO study results have shown that increasing dialysis dose in conventional thrice weekly hemodialysis does not improve patient outcomes. Interest has therefore turned to more frequent (daily) hemodialysis treatments. This review covers the rationale for such an approach together with a current review of the published study data. RECENT FINDINGS: Recent studies have suggested improvements in a number of intermediate patient outcomes such as cardiovascular (blood pressure control, left ventricular hypertrophy), anemia, phosphate control, nutritional status and quality of life. Some of these outcomes are associated with increased survival in the dialysis population. SUMMARY: The inference from these studies is that more frequent hemodialysis will indeed reduce mortality and morbidity. To date, however, the studies have all been small and underpowered to detect such primary outcomes. No randomized controlled trials are yet reported. The US National Institutes of Health have sponsored larger scale North American based studies and an International Registry of Daily Dialysis patients has been created to attain further information of the possible benefits of such therapy. In spite of the paucity of hard evidence the studies to date have been enough to convince some jurisdictions to recognize and fund daily hemodialysis treatments.

Humans↗

Vascular access.

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Catheterization↗

Nutrition.

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Biomarkers↗

Quality of life.

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Humans↗

The London Daily/Nocturnal Hemodialysis Study--study design, morbidity, and mortality results.

BACKGROUND: Despite the growing interest in more frequent hemodialysis (HD), to date, there have been no randomized prospective studies comparing outcomes in patients dialyzed using conventional thrice-weekly therapy with either the short hours daily or long slow nocturnal HD modalities. METHODS: The London Daily/Nocturnal Hemodialysis Study, a prospective, comparative, nonrandomized study, directly compared outcomes of quotidian HD patients with conventional thrice-weekly HD patients. Patients were assigned to either daily HD (n = 11) or nocturnal HD (n = 12) and followed up for 5 to 36 months; all data were directly compared with matched control patients receiving conventional HD. This report describes the study design, morbidity and mortality results, and vascular access results. RESULTS: There were no significant differences between patient groups in total numbers of hospital admissions or hospital days. Likewise, there was no significant difference in number of emergency visits per patient-year. There were 3 patient deaths in each of the nocturnal HD and control groups, although none of the deaths was deemed related to HD treatment. No deaths occurred in the daily HD group. Vascular access differences between study groups were not statistically significant. Among patients with arteriovenous (AV) fistulae, more than 80% of daily HD and nocturnal HD patients elected to use the buttonhole technique and successfully performed quotidian HD through their buttonhole at the 18-month follow-up. Patients with AV fistulae had the lowest annual rates of access complications and interventions. The annual access infection rate for quotidian HD patients using catheters decreased significantly after patients switched from in-center conventional HD to more frequent HD treatments at home. CONCLUSION: Results from this comprehensive and pioneering study support the hypothesis that quotidian HD is more physiological than conventional HD and results in better patient outcomes.

Adult↗

Volume control and blood pressure management in patients undergoing quotidian hemodialysis.

BACKGROUND: Hypertension and interdialytic weight gain are associated with left ventricular hypertrophy (LVH), an important predictor of cardiovascular mortality in hemodialysis (HD) patients. METHODS: In the London Daily/Nocturnal Hemodialysis Study, a group of patients receiving quotidian HD, either short daily (n = 11) or long nocturnal (n = 12), were followed for up to 18 months. Patients were assessed for effects of quotidian HD therapy on blood pressure, interdialytic weight gain, extracellular fluid volume (ECFV), intensity of antihypertensive therapy, and homocysteine levels. RESULTS: Significant reductions in predialysis mean arterial blood pressure were observed in the daily HD group at 6 months (P < 0.04) and in the nocturnal HD group at 9 months (P < 0.03); these improvements persisted throughout the study period. The daily HD group had a 60% reduction in mean number of antihypertensive tablets per day at 1 month and an 8.8-fold reduction by 18 months. Nocturnal HD patients experienced a 3.3-fold reduction, and control patients, a 1.4-fold increase in mean number of tablets per day by 18 months. By 3 months, the daily HD group showed a significant decrease in interdialytic weight gain (P < 0.0005) and lower ECFV than controls (P < 0.05). The nocturnal HD group had a transient, but significant, increase in interdialytic weight gain at 6 and 15 months (P < 0.05) and no difference in ECFV compared with controls, suggesting a different mechanism of blood pressure control. Homocysteine levels were significantly lower for both quotidian HD groups compared with conventional HD patients. CONCLUSION: Quotidian HD is a promising therapy with potent antihypertensive effects, resulting in improved blood pressure control. This, together with improved homocysteine levels, may be beneficial in the long term with regard to cardiovascular mortality.

Adult↗

Management of anemia with quotidian hemodialysis.

BACKGROUND: Most patients with end-stage renal disease have chronic anemia caused by inadequate erythropoietin (EPO) synthesis and require therapy with exogenous EPO to maintain recommended hematocrit and hemoglobin levels. METHODS: The London Daily/Nocturnal Hemodialysis Study compared anemia control among patients on either short daily, long nocturnal, or conventional thrice-weekly hemodialysis (HD) therapy. Patients were administered iron, either orally (900 mg/d) or intravenously (50 to 125 mg every 1 to 4 weeks), to maintain serum ferritin levels at greater than 45 ng/mL (100 microg/L) or transferrin saturations greater than 20%. EPO was administered by subcutaneous injection at frequencies ranging from twice weekly to once every second week to maintain hemoglobin levels within the target range of 11 to 12 g/dL (110 to 120 g/L). RESULTS: Both the daily HD and nocturnal HD study groups showed increased hemoglobin levels at later times compared with baseline levels, although only nocturnal HD patients had a statistically significant increase in hemoglobin levels at 18 months (11.94 g/dL [119.4 g/L] versus 10.95 g/dL [109.5 g/L] at baseline; P = 0.047). Both the daily HD and control groups showed a trend for decreased EPO dose requirements at later times compared with baseline, although these decreases were not statistically significant. The nocturnal HD group showed increased EPO dose requirements, although not statistically significant. CONCLUSION: Quotidian HD is associated with an increased quantity of blood loss that can account for some of the increased requirements in EPO dose. Additional studies with larger numbers of patients are needed to fully elucidate the effects of quotidian HD on anemia.

Adult↗