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Norbert Lameire

Publications and source records attributed to Norbert Lameire.

At least 91 records · Page 5Linked to original sources
PubMed2002

Behavior of non-protein-bound and protein-bound uremic solutes during daily hemodialysis.

BACKGROUND: In the last few years, renewed interest in daily short hemodialysis (DHD; six 2-hour sessions per week) has become apparent as a consequence of the better clinical outcome of patients treated by this schedule. Uremic syndrome is characterized by the retention of a large number of toxins with different molecular masses and chemical properties. Some toxins are water soluble and non-protein bound, whereas others are partially lipophilic and protein bound. There is increased evidence that protein-bound toxins are responsible for the biochemical and functional alterations present in uremic syndrome, and the kinetics of urea is not applicable to these substances for their removal. The aim of this study is to investigate whether DHD is accompanied by increased removal of non-protein-bound and protein-bound toxins and a decrease in their prehemodialysis (pre-HD) serum levels. PATIENTS AND METHODS: We studied 14 patients with end-stage renal disease treated by standard HD (SHD; three 4-hour sessions per week) for at least 6 months and randomly assigned them to a two-period crossover study (SHD to DHD and DHD to SHD). Patients maintained the same dialyzer, dialysate, and Kt/V during the entire study. At the end of 6 months of SHD and 6 months of DHD, we evaluated hemoglobin levels, hematocrits, recombinant human erythropoietin doses, and pre-HD and post-HD concentrations of serum urea, creatinine, uric acid, and the following protein-bound toxins: 3-carboxy-4-methyl-5-propyl-2-furanpropionic acid, p-cresol, indole-3-acetic acid, indoxyl sulfate, and hippuric acid. RESULTS: Values for hemoglobin, hematocrit, and recombinant human erythropoietin dose did not change during the two study periods. Pre-HD concentrations of creatinine, urea, and uric acid decreased on DHD (creatinine, from 8.7 +/- 1.9 to 7.8 +/- 1.6 mg/dL; P < 0.05; urea, from 149.4 +/- 28.8 to 132.7 +/- 40 mg/dL; P = 0.05; uric acid, from 9.14 +/- 1.49 to 8.16 +/- 1.98 mg/dL; P = 0.06). Concerning protein-bound toxins, lower pre-HD levels during DHD were reported for indole-3-acetic acid (SHD, 0.16 +/- 0.04 mg/dL; DHD, 0.13 +/- 0.03 mg/dL; P = 0.01), indoxyl sulfate (SHD, 3.35 +/- 1.68 mg/dL; DHD, 2.85 +/- 1.08 mg/dL; P = 0.02), and p-cresol at the borderline of significance (SHD, 0.96 +/- 0.59 mg/dL; DHD, 0.78 +/- 0.33 mg/dL; P = 0.07). CONCLUSION: Such non-protein-bound compounds as uric acid, creatinine, and urea were removed significantly better by DHD, and pre-HD serum levels were reduced. Furthermore, pre-HD concentrations of some protein-bound solutes, such as indole-3-acetic acid, indoxyl sulfate, and p-cresol, also were lower during DHD.

Creatinine↗
PubMed2002

An overview of morbidity and mortality in patients with acute renal failure due to crush syndrome: the Marmara earthquake experience.

BACKGROUND: On August 17, 1999 a major earthquake hit the most densely populated area at the eastern end of the Marmara Sea in northwestern Turkey. The number of documented cases of acute renal failure (ARF) following this event exceeded all similar cases previously reported for any single earthquake. The aim of this report was to provide an overview of the morbidity and mortality of all documented patients with ARF, due to crush injury, that were treated in hospitals with dialysis units following the Marmara earthquake. METHODS: Special questionnaires were sent out to all hospitals with dialysis units known to have admitted earthquake victims with ARF and related crush injuries. Responses to questionnaires from the Turkish Society of Nephrology (TSN) Task Force were collected from 35 hospitals in October 1999. We retrospectively evaluated patients, clinic and laboratory findings, surgical interventions, and frequency and duration of dialysis. Patients who died before or on admission and those with prior chronic renal disease were excluded from the study. RESULTS: A total of 639 patients (291 female and 348 male) with ARF due to crush injury were hospitalized in 35 hospitals. The mean age was 31.6+/-14.7 years and 71.1% were young adults within the range of 16-45 years. 477 patients (74.6%) received one or more dialysis treatments, 162 patients were not dialysed, 15 patients died before dialysis could be instituted, and 147 patients recovered without dialysis treatment. 340 patients were oliguric on admission. The most important abnormalities related to ARF as a result of crush injury morbidity, were oliguria (53.2%), uraemia (94%), high creatinine levels (87%), hyperkalaemia (42%), hyperphosphataemia (63%), hypocalcaemia (83%), and high creatinine phosphokinase levels (73 %). 512 patients had a total of 790 extremity injuries. Eighty-three patients (12.9%) had fractures of the extremities and non-extremity fractures were observed in 59 (9.2%) patients. 323 fasciotomies were performed. Thoracic and abdominal trauma was observed in 110 patients (17.2%). Infection and sepsis were observed in 223 (34.9%) and 121 (18.9%) patients, respectively. Haematologic abnormalities were observed in 197 patients (33%) including 116 with Htc < or =30%. There were pulmonary problems in 96 patients (15%), cardiovascular problems in 198 patients (30.9%), gastrointestinal problems in 23 (3.16%), neurologic problems in 43 (6.7%), and psychiatric problems in 7 (1%) patients. Ninety-seven of the 639 patients with ARF as a result of crush injury died (15.2%), and mortality rates were 17.2 and 9.3% in dialysed and non-dialysed patients, respectively. Findings significantly associated with mortality were sepsis, thrombocytopenia, disseminated intravascular coagulation (DIC), acute respiratory distress syndrome (ARDS), and abdominal and thoracic traumas. CONCLUSIONS: We conclude that in cases of severe disasters such as major earthquakes, patients should be rapidly transferred to undamaged peripheral general hospitals. When proper dialysis and intensive care facilities together with around the clock dedicated human effort are available, crush injury-related ARF patients have a lower mortality. Mortality, when it occurs, is mainly associated with thoracic and abdominal trauma and medical problems such as DIC and/or ARDS/respiratory failure, often in conjunction with sepsis.

Acute Kidney Injury↗
PubMed2002

Clinical findings in the renal victims of a catastrophic disaster: the Marmara earthquake.

BACKGROUND: The clinical course of acute renal failure (ARF) related to crush syndrome is very complex, because of co-existing surgical and/or medical complications. After the devastating Marmara earthquake that struck Turkey in August 1999, 639 patients were identified with nephrological problems, whose clinical findings have been the subject of this analysis. METHODS: Specific questionnaires asking about 63 variables were sent to 35 reference hospitals that treated the victims. Clinical findings of the renal victims were analysed. RESULTS: At admission, high fever was noted in 31.8% of the patients; the temperature of non-survivors was higher (P=0.027). Mean blood pressure was higher in survivors (P=0.004) and dialysed victims (P <0.001). Most (61.4%) patients were oligo-anuric; oliguria lasted for 10.8+/-7.2 days. Thoracic and abdominal traumas were associated with a higher risk of mortality. 397 fasciotomies and 121 amputations were performed in 790 traumatized extremities. Fasciotomies were associated with sepsis (P<0.001) and dialysis needs (P<0.0001), while amputations were associated with mortality (P<0.0001). Medical complications, which were associated with dialysis needs (P<0.0001) and mortality (P<0.0001), were observed in 51.5% of patients. In a multivariate analysis model of medical complications, disseminated intravascular coagulation (DIC) (P<0.0001, OR=5.81), and adult respiratory distress syndrome (ARDS) (P=0.0001, OR=4.53) were predictors of mortality. CONCLUSIONS: In the aftermath of catastrophic earthquakes, clinical findings of the renal victims can predict the final outcome. While fasciotomies indicate dialysis needs, extremity amputations, abdominal and thoracic traumas are associated with higher rates of mortality in addition to DIC and ARDS.

Acute Kidney Injury↗
PubMed2002

The Marmara earthquake: admission laboratory features of patients with nephrological problems.

BACKGROUND: Earthquakes are major causes of morbidity and mortality. North-western Turkey was struck by a devastating earthquake in August 1999, which caused several thousand deaths. Among the most important morbid events in survivors were acute nephrological problems. METHODS: Within the first week of the disaster, specific questionnaires asking about 63 clinical and laboratory parameters were sent to 35 reference hospitals that were treating the victims. Of the registered 639 victims, 423 were admitted within the first 3 days of the disaster; the admission laboratory data of these 423 patients are the subject of this analysis. RESULTS: In the 423 patients (233 males, mean age 31.3+/-14.4 years), time under the rubble was 10.7+/-10.4 h. Mean values at admission were as follows: serum potassium 5.4+/-1.3 mEq/l, creatine phosphokinase 58205+/-77889 IU/l, albumin 2.6+/-0.7 g/dl, phosphorus 5.2+/-1.8 mg/dl, haematocrit 35.0+/-9.3%, leukocyte count 14945+/-6614/mm(3), platelet count 183975+/-134012/mm(3), blood urea nitrogen 55.1+/-28.9 mg/dl, and creatinine 3.9+/-2.3 mg/dl. Serum potassium above 6.5 mEq/l was noted in 91 patients (22.7%), an alarming finding for risk of fatal arrhythmias. Non-survivors were characterized by higher figures of serum potassium (P=0.001), as well as lower haematocrit (P=0.028), platelets (P<0.001), and serum albumin (P=0.003). In a multivariate analysis model of admission laboratory parameters, serum creatinine (P<0.001, o.r.=2.19), potassium (P=0.001, o.r.=3.64), and phosphorus (P=0.004, o.r.=1.78) predicted dialysis needs, whereas serum albumin (P=0.028, o.r.=0.23) and creatinine (P=0.039, o.r.=0.60) were related to mortality. CONCLUSIONS: Admission laboratory data may be useful for predicting dialysis needs and survival chance of disaster victims. High incidences of some life-threatening abnormalities dictate the need for empirical therapy even in the field.

Acute Kidney Injury↗
PubMed2002

The role of trace elements in uraemic toxicity.

Although most research on uraemic toxicity has focused on the retention or removal of organic solutes, subtle changes in the concentration of inorganic compounds are also of importance because these compounds may have significant clinical consequences. Potential clinical implications include increased risk of cancer, cardiovascular disease, immune deficiency, anaemia, renal function impairment and bone disease. In uraemic patients, the most important factor affecting trace element concentration is the degree of renal failure and modality of renal replacement therapy. Accumulation of trace elements in haemodialysis patients has resulted from dialysate contaminated with aluminium and strontium. Several trace elements have been implicated in the decline of renal function. These include arsenic, cadmium, copper, germanium, lead and mercury. In uraemic patients, aluminium, cadmium, chromium, lanthanum, strontium and zinc have been shown to accumulate in bone. In addition to substantial evidence linking aluminium to renal osteodystrophy, studies have also implicated cadmium, iron and strontium in bone disease. Studies using a rat model of chronic renal failure have demonstrated an association between lanthanum accumulation and mineralization defects characteristic of osteomalacia. Investigations of arsenic accumulation in animal models have demonstrated that speciation of trace elements potentially may alter toxicities of trace elements accumulated in uraemic patients. Conversely, the presence of uraemic toxins may also alter the uptake and toxicity of certain trace elements. Although research in uraemic patients has focused primarily on total concentrations of trace elements, the evolution of both inorganic and organic species should be considered separately.

Bone and Bones↗
PubMed2002

Lessons learned from the Marmara disaster: Time period under the rubble.

OBJECTIVE: To investigate the effect of the time period under the rubble on morbidity and mortality of the crush-syndrome patients after the catastrophic Marmara earthquake that struck northwestern Turkey in August 1999. DESIGN: Observational study. SETTING: Consecutive admissions to emergency and intensive care units of 35 reference hospitals that treated the renal victims. METHODS: Analysis of questionnaires obtained from these hospitals. PATIENTS: A total of 539 of 639 crush-syndrome patients whose time under the rubble was identified in the questionnaires. RESULTS: Mean time under the rubble was 11.7 +/- 14.3 hrs (median, 8 hrs; interquartile range, 6 hrs; range, 0.5-135 hrs). The highest number of patients was entrapped within the 5-8 hrs time stratum, and by the end of 48 hrs, 97% of the victims had been rescued. Nondialyzed victims spent a longer duration under the rubble than dialyzed ones (15.9 +/- 23.1 hrs [median, 7 hrs; interquartile range, 8.5 hrs] vs. 10.3 +/- 9.5 hrs [median, 8 hrs; interquartile range, 6 hrs), p <.001)]. Likewise, in the strata of longer time under the rubble, the percentage of survivors was higher (p =.07). Time under the rubble correlated positively with the number of amputated extremities (p <.001) and admission platelet count (p <.001), and it correlated negatively with admission serum albumin (p <.001). The victims entrapped for >50 hrs (n = 6) were characterized by lower figures of admission blood urea nitrogen (p =.04), serum creatinine (p =.003), hemodialysis sessions, and duration of hemodialysis support (p =.005, for both analyses) compared with victims whose time under the rubble was shorter. CONCLUSION: Rescue efforts should continue at least for 5 days after the disaster. Time under the rubble is not an adverse prognostic indicator of survival or renal dysfunction for the patients of crush syndrome, probably because only the victims with mild or moderate injuries can survive under the rubble for longer durations.

Adolescent↗
PubMed2002

Developing a consensus classification system for acute renal failure.

A biochemical definition and classification system for acute renal dysfunction is long overdue. Its absence has impeded progress in clinical and even basic research concerning a syndrome associated with mortality rates of 30 to 80%. No definition of acute renal dysfunction will be perfect, but the absence of a definition or, worse, more than 35 separate definitions, as found in the literature, is unacceptable. Many of the challenges, considerations, and controversies associated with achieving consensus and developing a classification for acute renal dysfunction are addressed. Recommendations for validating a classification system are also considered.

Acute Kidney Injury↗
PubMed2002

Management of the hemodialysis patient: a European perspective.

This article explores some of the factors which may contribute to the persistence of the differences in outcome between European and US hemodialysis patients. A higher comorbidity of incident and prevalent renal replacement therapy patients, different vascular access policies with less use of arteriovenous fistulas, shorter dialysis times, and higher reutilization of dialysis membranes in the USA may, among other factors, explain the higher mortality compared to Europe and Japan. No major differences in patient referral to the nephrologist, in residual renal function at the start of dialysis, nor in the dialysis dose based on Kt/V urea data were noted.

Catheters, Indwelling↗
PubMed2002

Treatment modalities and outcome of the renal victims of the Marmara earthquake.

BACKGROUND/AIMS: Treatment of renal problems during natural catastrophes is highly complicated both for medical and logistic reasons. The therapeutic interventions applied to and the outcome of 639 victims with acute renal problems during the catastrophic Marmara earthquake have been the subject of this study. METHODS: Questionnaires regarding information about 63 clinical and laboratory variables were sent to 35 reference hospitals that treated the victims. Information considering therapeutic interventions and outcome obtained through these questionnaires was submitted to analysis. RESULTS: At least one form of renal replacement therapy was administered to 477 (74.6%) of the 639 victims. Of these, 437, 11, and 4 were treated solely by intermittent hemodialysis, continuous renal replacement therapy, and peritoneal dialysis, respectively; 25 victims needed more than one dialysis modality. In total, 5,137 hemodialysis sessions were performed. Also, 2,981, 2,837 and 2,594 units of blood, fresh frozen plasma, and human albumin were administered, respectively. Transfusion of these products was usually associated with higher rates of dialysis needs and mortality. Ninety-seven patients (15.2%) died. The mortality rate of dialyzed victims was higher as compared to nondialyzed ones (17.2 vs. 9.3%, p = 0.015). CONCLUSIONS: Massive amounts of dialysis treatment as well as blood and blood product transfusions can be necessary in the treatment of catastrophic earthquake victims with nephrological problems. Despite the potential risk of a high mortality, in the case of appropriate and energetic medical interventions, reasonable final outcomes can be achieved.

Acute Kidney Injury↗
PubMed2002

The impact of healthy start peritoneal dialysis on the evolution of residual renal function and nutrition parameters.

The optimal time to start renal replacement therapy remains controversial. Residual renal function (RRF) and nutrition status being important prognostic factors, the present study evaluates the impact of timely start of peritoneal dialysis (PD) on their evolution. Our study used a prospective database on pre-end-stage renal disease patients at a tertiary care center. We included 18 patients who were planned to start PD at a GFR > 8 mL/min between 1 January and 31 December 1999. At the start of PD (month 0), creatinine clearance (CCr) was 11.3 +/- 3.9 mL/min, actual glomerular filtration rate (GFR) was 8.6 +/- 3.3 mL/min, and Kt/V was 1.56 +/- 0.65. The monthly declines of GFR and CCr before and after the start of PD were -0.47 +/- 0.64 mL/min (GFR) and -0.59 +/- 0.46 mL/min (CCr), and -0.06 +/- 0.30 mL/min (GFR) and -0.05 +/- 0.39 mL/min (CCr) respectively (p = 0.034 and 0.001, respectively). Before the start of PD, CCr was 21.9 +/- 4.6 mL/min (month -12) and 18.1 +/- 4.8 mL/min (month -6, p < 0.001). After the start of PD, CCr was 12.0 +/- 4.3 mL/min (month 3), 11.5 +/- 4.9 mL/min (month 6), and 13.1 +/- 5.4 mL/min (month 12, p = 0.9). Serum albumin dropped until just before the start of PD: 3.89 +/- 0.59 g/dL (month -6) and 3.78 +/- 0.51 g/dL (month -3) versus 2.56 +/- 1.60 g/dL (month 0, p = 0.04). Serum albumin then increased to 3.42 +/- 0.95 mg/dL (month 3 after the start of PD) and 3.35 +/- 0.86 mg/dL (month 6 after the start of PD, p = 0.04). In the months preceding the start of PD, the normalized protein catabolic rate (nPCR) dropped from 1.41 +/- 0.36 g/kg daily (month -6) and 1.34 +/- 0.46 g/kg daily (month -3) to 1.12 +/- 0.25 g/kg daily (month 0). It then stabilized at 1.17 +/- 0.25 g/kg daily (month 3) and 1.18 +/- 0.17 g/kg daily (months 6). One patient died owing to a cerebrovascular accident after 18 months of PD, and one was transferred to hemodialysis because of ultrafiltration failure after 19 months of PD. During 264 patient-months, 14 peritonitis episodes occurred. Of the 14 episodes, 12 resolved without complication, and the catheter was replaced in 2 episodes. After timely start of PD, the rate of RRF decline decreases. Already, at a GFR > 8 mL/min, uremia has a negative impact on nutrition parameters. Timely initiation of PD could reverse the negative evolution of albumin and stop the decline of nPCR. No severe complications related to PD were seen. In view of the important impact of RRF and nutrition on patient outcome, our data may favor an early start of PD.

Creatinine↗
PubMed2001

Chronic uremia induces permeability changes, increased nitric oxide synthase expression, and structural modifications in the peritoneum.

Advanced glycation end products (AGE), growth factors, and nitric oxide contribute to alterations of the peritoneum during peritoneal dialysis (PD). These mediators are also involved in chronic uremia, a condition associated with increased permeability of serosal membranes. It is unknown whether chronic uremia per se modifies the peritoneum before PD initiation. A rat model of subtotal nephrectomy was used to measure peritoneal permeability after 3, 6, and 9 wk, in parallel with peritoneal nitric oxide synthase (NOS) isoform expression and activity and structural changes. Uremic rats were characterized by a higher peritoneal permeability for small solutes and an increased NOS activity due to the up-regulation of endothelial and neuronal NOS. The permeability changes and increased NOS activities correlated with the degree of renal failure. Focal areas of vascular proliferation and fibrosis were detected in uremic rats, in relation with a transient up-regulation of vascular endothelial growth factor and basic fibroblast growth factor, as well as vascular deposits of the AGE carboxymethyllysine and pentosidine. Correction of anemia with erythropoietin did not prevent the permeability or structural changes in uremic rats. Thus, in this rat model, uremia induces permeability and structural changes in the peritoneum, in parallel with AGE deposits and up-regulation of specific NOS isoforms and growth factors. These data suggest an independent contribution of uremia in the peritoneal changes during PD and offer a paradigm to better understand the modifications of serosal membranes in uremia.

Anemia↗
PubMed2000

Rhabdomyolysis.

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Acute Kidney Injury↗
PubMedDate not supplied

Acute renal failure.

This seminar covers the most recent information on definition, epidemiology, and clinical causes of acute renal failure. The mechanisms of acute prerenal failure and the potential interference by commonly used drugs of autoregulation of renal blood flow are discussed. We summarise some basic and recent insights into the haemodynamic and cellular pathophysiological mechanisms, mainly of postischaemic acute renal failure. Recent findings on the repair mechanisms of renal injury and the potential future therapeutic possibilities are discussed. We provide some differential diagnostic approaches for patients with acute renal failure and summarise prevention of the disorder and management of critically ill patients by dialysis and by other means. Finally, some information on the influence of gene polymorphisms on the prognosis of acute renal failure is given.

Acute Kidney Injury↗
PubMedDate not supplied

The dialytic management of acute renal failure in the elderly.

In this article the different dialysis strategies in the management of acute renal failure (ARF) in the elderly are discussed. Although peritoneal dialysis (PD) offers some theoretical advantages, there are several medical and technical reasons why it is currently less frequently used. The choice between intermittent hemodialysis (HD) and continuous renal replacement therapy (CRRT) is determined by a number of considerations, the most important ones being hemodynamic stability, the need for hyperalimentation and/or ultrafiltration, and the local experience with one or both techniques. Some recent studies with CRRT in elderly ARF patients describe favorable results. Slow extended daily dialysis (SLEDD) modalities may be particularly indicated in elderly, critically ill ARF patients because these techniques combine the advantages of both CRRT and HD. Finally, the importance of the biocompatibility of dialysis membranes is discussed. Although there are a number of theoretical arguments to use biocompatible membranes, this opinion is not always supported by the results of recent comparative studies. It is the opinion of the authors that all dialysis strategies should be mastered and utilized for appropriate indications in elderly ARF patients.

Acute Kidney Injury↗