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T A Golper

Publications and source records attributed to T A Golper.

At least 19 recordsLinked to original sources
PubMed2001

Sustained low-efficiency dialysis for critically ill patients requiring renal replacement therapy.

BACKGROUND: The replacement of renal function for critically ill patients is procedurally complex and expensive, and none of the available techniques have proven superiority in terms of benefit to patient mortality. In hemodynamically unstable or severely catabolic patients, however, the continuous therapies have practical and theoretical advantages when compared with conventional intermittent hemodialysis (IHD). METHODS: We present a single center experience accumulated over 18 months since July 1998 with a hybrid technique named sustained low-efficiency dialysis (SLED), in which standard IHD equipment was used with reduced dialysate and blood flow rates. Twelve-hour treatments were performed nocturnally, allowing unrestricted access to the patient for daytime procedures and tests. RESULTS: One hundred forty-five SLED treatments were performed in 37 critically ill patients in whom IHD had failed or been withheld. The overall mean SLED treatment duration was 10.4 hours because 51 SLED treatments were prematurely discontinued. Of these discontinuations, 11 were for intractable hypotension, and the majority of the remainder was for extracorporeal blood circuit clotting. Hemodynamic stability was maintained during most SLED treatments, allowing the achievement of prescribed ultrafiltration goals in most cases with an overall mean shortfall of only 240 mL per treatment. Direct dialysis quantification in nine patients showed a mean delivered double-pool Kt/V of 1.36 per (completed) treatment. Mean phosphate removal was 1.5 g per treatment. Mild hypophosphatemia and/or hypokalemia requiring supplementation were observed in 25 treatments. Observed hospital mortality was 62.2%, which was not significantly different from the expected mortality as determined from the APACHE II illness severity scoring system. CONCLUSIONS: SLED is a viable alternative to traditional continuous renal replacement therapies for critically ill patients in whom IHD has failed or been withheld, although prospective studies directly comparing two modalities are required to define the exact role for SLED in this setting.

APACHE↗
PubMed2000

Methods used to evaluate the quality of evidence underlying the National Kidney Foundation-Dialysis Outcomes Quality Initiative Clinical Practice Guidelines: description, findings, and implications.

This report describes the approach the National Kidney Foundation-Dialysis Outcomes Quality Initiative (NKF-DOQI) used to assess the strength of published evidence pertinent to individual NKF-DOQI Clinical Practice Guidelines, as well as the relationship between that approach and methods used by the US Preventive Services Task Force, the Cochrane Collaboration, and the Agency for Health Care Policy and Research to rate the quality and/or strength of evidence. We also present the results of an analysis of the strength of evidence underlying the NKF-DOQI Guidelines showing that one cannot infer the quality of evidence reported in a study (rated either on a 0-to-1 scale or categorically as excellent, very good, good, fair, or poor) simply by knowing the type of study design used (randomized trial, nonrandomized trial, natural experiment, cohort study, cross-sectional study, case-control study, case report). Issues related to assessment of the strength of evidence underlying a practice guideline opposed to that reported in an individual study are highlighted.

Evidence-Based Medicine↗
PubMed2000

Impaired biological activity of erythropoietin by cyanate carbamylation.

AIMS: During advanced renal failure, particularly in patients with end-stage renal disease (ESRD), proteins are carbamylated as a result of a reaction with cyanate. Some or all of the cyanate is derived from urea. If the carbamylation of proteins adversely alters their biologic activities, then urea must be viewed as an uremic toxin, rather than a surrogate. Therefore, we studied the effect of cyanate carbamylation on the erythropoietic activity of erythropoietin (EPO) in a rodent model. METHODS: EPO was carbamylated by incubation with cyanate at 37 degrees C. The extent of carbamylation was monitored using trinitrobenzenesulfonic acid. In Sprague-Dawley rats the erythrocyte count, hemoglobin concentration, and hematocrit were measured after the twice-weekly subcutaneous injection of either EPO or carbamylated EPO for 3 weeks. Two additional control groups received physiologic saline or 0.2 ml of 1 M cyanate. RESULTS: The level of carbamylated EPO was increased as the time of exposure to cyanate increased from 1 to 6 h, and as the cyanate concentration increased from 8 to 2,000 mM. EPO injections caused significantly large increases in all erythropoietic measures. Physiologic saline or 1 M cyanate-injected controls and the carbamylated EPO-injected animals demonstrated no change from baseline in erythropoietic parameters. CONCLUSION: These results support that EPO exposed to high levels of cyanate in vitro demonstrates diminished biologic activity in healthy Sprague-Dawley rats. This effect may be manifested by the carbamylation of EPO by the cyanate. Should this occur in ESRD patients, it may contribute to the suboptimal erythropoietic response to EPO therapy associated with high urea levels, especially related to inadequate dialysis. Targeting dialysis doses specifically to urea concentrations may be more important than previously considered.

Animals↗
PubMed1999

Predialysis blood pressure and mortality risk in a national sample of maintenance hemodialysis patients.

The role of predialysis blood pressure (BP) as a risk factor for the high mortality in chronic hemodialysis (HD) patients has remained controversial. The objective of the current study was to further explore in a national random sample of 4,499 US hemodialysis patients any relationship of systolic or diastolic and predialysis or postdialysis BP with mortality, while considering subgroups of patients and controlling for other patient characteristics and comorbidities. The main finding of this study is the association of a low predialysis systolic BP with an elevated adjusted mortality risk (relative mortality risk [RR] = 1.86 for systolic BP < 110, P < 0.0001). No association with an elevated mortality risk could be observed for predialysis systolic hypertension (RR = 0.98 to 0.99, not significant [NS]), except for an elevated risk of cerebrovascular deaths. Postdialysis systolic BP was associated with an elevated mortality risk both for low and high BP levels as compared with midrange BP. Further evaluation of the elevated mortality risk associated with low predialysis systolic BP indicated similar patterns for both diabetic and nondiabetic subgroups and for patients with and without congestive heart failure (CHF) or coronary artery disease, although it was more pronounced among those with CHF. The level of predialysis fluid excess did not modify these results substantially. The findings from this historical prospective national study do not argue against the treatment of hypertension and suggest greater attention to postdialysis hypertension. The strikingly elevated mortality risk with low predialysis systolic BP suggests that low predialysis BP needs to be viewed with great concern and avoided where possible.

Adult↗
PubMed1999

Morbidity and mortality in redefining adequacy of peritoneal dialysis: a step beyond the National Kidney Foundation Dialysis Outcomes Quality Initiative.

The National Kidney Foundation Dialysis Outcomes Quality Initiative (NKF-DOQI) Peritoneal Dialysis (PD) Adequacy Work Group intentionally limited the scope of its work to address adequacy in terms of small-solute removal. This decision was based on the need for rigorous evidence and that mortality is the most objective parameter in the literature. This review attempts to more broadly redefine the concept of the adequacy of PD, particularly as it relates to the most common general medical problems that PD patients experience; namely, cardiovascular disease and malnutrition. Whereas we are sensitive to the developmental process of the NKF-DOQI, we are critical that the definition of adequacy may be too narrow, leading clinicians to overlook other important morbidities. We have reiterated the evidence that suggests a weekly solute clearance (Kt/Vurea) of 1.7 or greater is associated with better patient survival. The arguments to target a greater Kt/Vurea of 2.0 are challenged, yet the concept is ultimately supported. Because cardiovascular disease is the cause of death in half of all patients with end-stage renal disease, dialysis adequacy must be defined, in part, by the potential of that therapy to diminish cardiovascular maladies. Blood pressure, volume, left ventricular hypertrophy, and dyslipidemias are discussed in this context. Lastly, assumptions that increasing total solute clearance leads to improved nutrition in PD patients are challenged. We have attempted to expand on what the NKF-DOQI did not include, and we urge the dialysis community to seek the answers to the many controversies that remain. We need to redefine the adequacy of PD in a holistic manner and find outcome parameters that are not as final as death.

Cardiovascular Diseases↗
PubMed1999

Implementation of the Peritoneal Dialysis Adequacy Guidelines: a personal perspective.

I describe some of the political issues surrounding the National Kidney Foundation-Dialysis Outcomes Quality Initiative project as I perceived them. I then discuss what I would do differently, what I recommend to encourage implementation, and why regulatory concerns are well founded. I close with technical issues including expansion, simplification, and corrections.

Female↗
PubMed1999

Tumour lysis syndrome complicating high-dose treatment in patients with multiple myeloma.

Tumour lysis syndrome (TLS), because of its low proliferative activity, is thought to only rarely complicate the treatment of patients with multiple myeloma. However, as more aggressive therapeutic approaches are increasingly used in the management of this disease, it is conceivable that clinicians will encounter this complication more frequently. A retrospective analysis of > 800 patients with multiple myeloma treated at the University of Arkansas identified nine patients who developed a marked tumour lysis syndrome following intermediate- or high-dose chemotherapy. Evaluation of disease characteristics revealed association with high tumour mass, high proliferative activity, increased lactic dehydrogenase levels, plasmablastic morphology, and unfavourable cytogenetic abnormalities. Recognition of multiple myeloma patients at high risk for the development of tumour lysis syndrome and prompt intervention are required especially in the presence of abnormal baseline renal function frequently complicating the clinical course of these patients.

Adult↗
PubMed1998

Noncompliance in hemodialysis: predictors and survival analysis.

Noncompliance with hemodialysis (HD), depending on the definition, occurs in 2% to more than 50% of patients. To better understand predictors and outcomes of noncompliance, we evaluated patient characteristics associated with noncompliance and the impact of noncompliance on survival. Using data from two USRDS special studies, we identified 6,251 patients who were on dialysis for more than 1 year for inclusion in this study. Noncompliance was defined in four ways: skipping one or more HD sessions in a month, shortening by 10 or more minutes one or more HD sessions in a month, an interdialytic weight gain (IWG) of more than 5.7% of dry weight, or a serum phosphate (PO4) of greater than 7.5 mg/dL. Sociodemographic predictors of noncompliance were identified using logistic regression. Survival analysis was done using Cox proportional hazards models with adjustments for sociodemographics, comorbid conditions, and dose of HD. Overall, 8.5% of patients skipped HD, 20% shortened HD (7% three or more times), 10% had more than a 5.7% IWG, and 22% had a PO4 greater than 7.5. There was a significant correlation among the measures of noncompliance. Blacks (adjusted odds ratio [AOR] = 2.10), patients aged 20 to 39 years (AOR = 1.62), and smokers (AOR = 1.34) were significantly more likely to skip HD than whites, patients aged 40 to 59 years, and nonsmokers, respectively (P < 0.01 for each). Similar results were seen for the other measures of noncompliance, except for PO4, in which blacks were significantly less likely to be noncompliant (NC) (AOR = 0.85, P < 0.05). Compared with compliant patients, those who skipped one or more HD sessions in a month had a 25% higher risk of death (P < 0.01). Those who had greater than a 5.7% IWG had a 35% higher risk of death (P < 0.001), whereas those with a PO4 > 7.5 had a 13% higher risk of death (P < 0.05). Overall, patients who shortened HD sessions did not have a higher risk of death, but those who shortened three or more in 1 month had a 20% higher risk of death (P < 0.05). Compliance with a medical regimen is a complex issue. Noncompliance in HD often, but not always, is associated with a higher risk of an adverse outcome. This is a US government work. There are no restrictions on its use.

Adult↗
PubMed1998

Quality of life during and between hemodialysis treatments: role of L-carnitine supplementation.

End-stage renal disease affects every aspect of a patient's life, including perception of health and quality of life. It is likely that a hemodialysis patient's perceptions of health-related quality of life directly influence compliance with medical, nursing, and nutritional prescriptions. Because L-carnitine supplementation is known to enhance muscle strength and energy in hemodialysis patients, we hypothesized that L-carnitine supplementation would enhance a hemodialysis patient's perception of health-related quality of life. To test this hypothesis, 1 g L-carnitine or placebo was administered orally to 101 patients immediately before and after every hemodialysis treatment for 6 months. To assess health-related quality of life from the patient's perspective, the Medical Outcomes Study Short Form 36 instrument was administered before the study and at 1.5-month intervals for the duration of the study. In addition, a 10-item questionnaire designed to assess common intradialytic symptoms was administered at the end of each dialysis treatment. Other parameters analyzed included Kt/V(urea) and level of nutrition. In the 6-month group, oral L-carnitine supplementation had an early positive effect on general health (P < 0.02) and physical function (P < 0.03), but the perceived effect was not sustained throughout the 6 months of the study. In the 3-month group, L-carnitine supplementation improved vitality (P < 0.02) and general health (P < 0.01). There was no association between Kt/V(urea) and perceived health-related quality of life. Serum albumin concentration was directly correlated to how patients perceived the quality of their lives.

Administration, Oral↗
PubMed1998

Cefazolin as empiric therapy in hemodialysis-related infections: efficacy and blood concentrations.

Concern about the increasing incidence of vancomycin-resistant organisms has tempered the enthusiasm for indiscriminate vancomycin use. Cefazolin has an antibacterial activity profile similar to vancomycin against most pathogens encountered in the hemodialysis (HD) population. We evaluated the clinical efficacy and serum concentrations that were achieved during empiric cefazolin use. Fifteen consecutive HD patients (five, conventional HD; five, high-efficiency HD; and five, high-flux HD) with suspected or documented infections warranting antibiotic intervention, including access-related, respiratory tract, urinary tract, or wound infections, were enrolled. Each patient received intravenous cefazolin (20 mg/kg actual body weight rounded to the nearest 500-mg increment [range, 1 to 2 g]) after each dialysis treatment for at least three doses. Cefazolin concentrations were obtained before and immediately after the next three consecutive dialysis treatments. Thirteen patients were evaluated for efficacy and all 15 were evaluated for toxicity and cefazolin blood concentrations. All patients showed at least a short-term (3-week) clinical resolution of infection with cefazolin treatment. No central nervous system toxicities were noted and no other adverse events were expressed by the patients during the course of cefazolin treatment. Predialysis cefazolin concentrations, as determined by high-performance liquid chromatography, were 70.2 +/- 42.7 (conventional HD), 45.6 +/- 18.9 (high-efficiency HD), and 41.6 +/- 23.9 mg/L (high-flux HD) over the three dialysis sessions. Cefazolin at doses of approximately 20 mg/kg administered post-HD appears to be a safe and effective empiric therapy and yields predialysis cefazolin concentrations of 2.5 times or greater than those considered to be the minimum inhibitory concentration breakpoint (16 mg/L) for susceptible organisms. These data support the broader use of cefazolin for empiric treatment in the HD population, allowing vancomycin to be reserved for confirmed resistant organisms.

Adult↗
PubMed1998

Incremental dialysis.

The National Kidney Foundation-Dialysis Outcome Quality Initiative Peritoneal Dialysis Adequacy Clinical Practice Guideline 1 and Appendix A offered the first formal in-depth discussion of the concept of incremental dialysis (1). The context of the work group's concern was that it is paradoxical that we nephrologists have focused on optimizing urea clearance for end-stage renal disease patients, but not in pre-end-stage renal disease patients. Because so much evidence from the collective peritoneal dialysis experience suggested that a weekly Kt/Vurea of 2.0 is appropriate, the National Kidney Foundation-Dialysis Outcome Quality Initiative Peritoneal Dialysis Adequacy Work Group recommended that when the residual renal Kt/Vurea drops below 2.0, supplemental Kt/Vurea should be added incrementally by dialysis. This article describes this concept in more detail.

Female↗