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Norbert Lameire

Publications and source records attributed to Norbert Lameire.

102 records · Page 6Linked to original sources

Peritoneal dialysis in anuric patients: concerns and cautions.

Most recent studies have found an equivalent survival for patients on peritoneal dialysis (PD) and hemodialysis (HD); evidence even suggests that PD might be the preferred modality during the first 3-4 years of renal replacement therapy. This is probably related to the continuous and minimally invasive character of PD as compared to HD, resulting in better preservation of residual renal function (RRF) and less cardiovascular strain. On the other hand, blood pressure control, fluid balance, and adequacy targets may be difficult to obtain in long-term PD patients. The question arises whether PD is a feasible option in anuric patients. It is clear that the answer depends on the body size and the peritoneal membrane transport characteristics of the patient, so that PD will be feasible in some anuric patients, whereas in others it will not be. Evaluation of the peritoneal transport characteristics and adaptation of the PD prescription is warranted. A constant evaluation of the fluid balance, nutritional, and cardiovascular status is needed. This article reviews the physiologic insights and clinical evidence necessary for a good PD prescription in anuric patients.

Anuria↗

The other side of the coin: impact of toxin generation and nutrition on the uremic syndrome.

Both the morbidity of the uremic syndrome and the generation of uremic toxins are attributed to malnutrition. If protein intake and catabolism result in the generation of solutes, then nutritional intake should be related directly to toxicity. On the other hand, inadequate nutrition has been linked to inflammation and mortality. It remains difficult to reconcile these two lines of thought. Several possibilities exist that might account for this apparent paradox: 1) not all nutritional and protein degradation products are toxic; 2) toxins generated from increased protein intake are removed if protein intake is linked to dialysis dose; 3) albumin acts as a buffer for toxicity-hypoalbuminemia favors liberation of protein-bound toxins from their binding sites, enhancing their toxicity; 4) solutes generated from tissue breakdown are more toxic than those generated by nutritional protein; 5) both high and low concentrations of solutes have a negative impact; 6) toxic compounds unrelated to protein breakdown are specific causes of malnutrition and inflammation; 7) and/or residual renal function plays a key role in the elimination of compounds discussed under possibility 6. Thus the uremic syndrome should be considered as a potentially fatal interaction among inflammation, malnutrition, low levels of albumin in the plasma, accumulated protein-bound solutes and generation of nonnutritionally related toxins. Not only optimal dialysis, but also optimal nutritional intake and optimal utilization of these nutrients should help neutralize this chain of events.

Dietary Proteins↗

The role of APD in the improvement of outcomes in an ESRD program.

We review the role of automated peritoneal dialysis (APD) in improving outcomes of an end-stage renal disease (ESRD) program. As the "integrated care approach" becomes accepted as the preferred strategy for treatment of ESRD patients, we looked for the potential place of APD in such an approach. APD has probably the same advantages as CAPD as a first-line renal replacement modality in suitable patients willing to perform PD. There is currently no hard evidence that residual renal function (RRF) should decline more rapidly in APD than in CAPD, at least if a dry abdomen during the day is avoided. The detection of peritonitis is probably more delayed in APD, but the frequency of peritonitis is lower, and there is no hard evidence pointing to a poorer outcome of peritonitis in APD as compared to CAPD. Quality of life is at least as good in APD, which is mostly related to the increased possibilities for adapting the exchange pattern to employment-related time frames. APD also has the potential to prolong technique success in patients failing CAPD rather than transferring them to hemodialysis. Nevertheless, APD remains more expensive and technically complicated, thereby missing the beauty of CAPD's simplicity. Therefore we believe that APD has its role in an integrated approach and that all patients should be informed of its potential. It would, however, not be correct to present APD as the preferred PD method for all patients, as it also has some drawbacks that make it less suitable for some categories of patients. In all cases, patients should have a free and informed choice.

Automation↗

Increased leukocyte rolling in newly formed mesenteric vessels in the rat during peritoneal dialysis.

OBJECTIVE: Long-term peritoneal dialysis (PD) is associated with the development of functional and structural alterations of the peritoneal membrane. The present study reports the effects of chronic exposure to PD fluid on mesenteric leukocyte-endothelium interactions, using intravital video microscopy. METHODS: Rats (n = 7) received 10 mL lactate-buffered 3.86% glucose-containing PD fluid daily during a 5-week period via a subcutaneously implanted mini access port that was connected via a catheter to the peritoneal cavity. In a first control group (n = 8), catheters were implanted but no fluid was instilled; a second control group (n = 8) remained untreated. The number of rolling and adherent leukocytes as well as blood flow and other fluid dynamic variables were analyzed in mesenteric postcapillary (diameter 10-25 mu) and collecting (diameter 26-40 mu) venules. Neovascularization was semiquantitatively assessed after inspection of video images and by light and electron microscopy. Using FITC-labeled albumin, microvascular leakage was examined. RESULTS: Rats exposed to PD fluid showed a more than twofold increase in the number of rolling leukocytes (p < 0.01); the number of adherent leukocytes was not changed. Furthermore, exposure to PD fluid induced severe neovascularization in rat mesentery. No microvascular leakage was observed in the various groups. The observed differences could not be explained by differences in systemic or local hemodynamic parameters or peripheral leukocyte counts, but is most likely associated with new vessel formation. CONCLUSIONS: Exposure of rat peritoneal membrane to conventional PD fluid for 5 weeks affected local leukocyte-endothelium interactions. In addition, severe angiogenesis was induced, whereas microvascular permeability remained unaltered.

Animals↗

The role of ultrasonography in the assessment of renal function in the elderly.

BACKGROUND: Ageing is associated with a progressive loss of renal mass and kidney length and a decline in glomerular filtration rate (GFR). This study evaluated a possible correlation between renal function and kidney size measured by ultrasonography (US), and whether the latter helps estimate GFR in the elderly. METHODS: Twenty-five medically stable elderly patients (mean age 85 +/- 5 yrs) were examined in a geriatric ward at a university hospital. Blood samples were taken to determine serum creatinine (Cr) levels. On the same day, 51chromium ethylenediamine tetraacetic acid (51Cr-EDTA) clearance was performed as the gold standard of GFR. US measured kidney length, transverse and anteroposterior dimensions. RESULTS: Serum Cr (r=-0.67; p=0.0002), Cockcroft-Gault formula (r=0.82; p<0.0001), absolute length (r=0.51; p=0.008) and volume kidney (r=0.46; p=0.02) correlated significantly with GFR. After receiver operating curve (ROC) analysis, length was less specific than sensitive in detecting renal impairment. Adding length to the Cockcroft-Gault formula did not improve GFR estimation (p=0.44). In contrast, adding length to serum Cr levels improved GFR estimation (p=0.015). CONCLUSION: In the elderly, kidney length and volume significantly correlated with GFR. However, length has a low specificity in predicting renal impairment. Therefore, in clinical practice, serum Cr levels and calculated Cr clearance are more useful in predicting renal impairment. However, normal kidney length can help to exclude renal impairment in the elderly at risk of GFR underestimation by a calculated Cr clearance.

Aged↗

A randomized clinical trial with a 0.6% amino acid/ 1.4% glycerol peritoneal dialysis solution.

BACKGROUND: Glucose is an accepted osmotic agent for peritoneal dialysis (PD) although it has several drawbacks. Some of these drawbacks have been addressed by the introduction of solutions with low glucose degradation products and physiological pH in dual-chambered bags. Despite this achievement, there is a need for alternative osmotic agents.This randomized clinical trial analyzes 3-month's clinical experience with a mixture of 0.6% amino acids and 1.4% glycerol. METHODS: The study was performed at the renal units of the University Hospitals Ghent, Belgium, and Utrecht, The Netherlands. Stable PD patients were randomized for either protocol A (test solution, n = 5) or protocol B (control regimen, n = 5). In both protocols, there was a run-in phase of 1 month with a dialysis regimen of 2 x 2 L 2.27% glucose solution (Dianeal; Baxter, Nivelles, Belgium), 1 x 2 L Extraneal (Baxter), and 1 x 2 L glucose solution (Dianeal). After this month-long run-in period, patients in group A received during 3 months 2 x 2 L amino acid/glycerol solution, 1 x 2 L Extraneal, and at least 1 x 2 L of a classic glucose solution. RESULTS: Glucose absorption decreased in the test group during the test phase (from 84.2 +/- 8.7 to 11.7 +/- 11.6 g/24 hours, p = 0.001). Dialysate levels of cancer antigen 125 (CA125) increased in the test group, from 17.5 +/- 11.0 to 32.4 +/- 4.6 units/L (p = 0.04), whereas, in the control group, the levels remained stable (15.5 +/- 8.7 and 14.9 +/- 9.8 units/L respectively, p = 0.4). There were no differences in serum urea, serum bicarbonate, serum osmolarity, serum albumin, or parameters related to skin-fold thickness or serum glycerol levels between control and test solutions. No differences were observed in obtained ultrafiltration after a 4-hour dwell with 2.27% glucose or the test solution, both measured at week 4 of the run-in period and week 12 of the test period. CONCLUSION: This study demonstrated that the use of a new 0.6% amino acid/1.4% glycerol-containing dialysis solution is safe and well tolerated. Glucose load was reduced significantly and dialysate CA125 levels improved significantly. Ultrafiltration was comparable with that of a 2.27% glucose solution. All these factors, in combination with the potential nutritional benefits, can contribute to a beneficial impact on the success of the PD technique. Further long-term studies in larger patient groups are warranted to explore the potential of this promising new solution.

Adult↗

Effect of gender on various parameters of crush syndrome victims of the Marmara earthquake.

BACKGROUND: Detailed analyses on crush syndrome resulting from earthquakes is scarce. This study aimed to analyze the effect of gender on clinical course of the renal victims of the catastrophic Marmara earthquake that struck Northwestern Turkey in 1999. METHODS: Questionnaires were prepared within the first week of disaster and sent to 35 reference hospitals that treated the victims. Relationship between gender and various epidemiological, clinical, laboratory parameters, treatment modalities and outcome was then investigated. RESULTS: Of the 639 victims with renal dysfunction, 348 (54%) were males and 291 (46%) females. Mean age was 33 +/- 14 and 31 +/- 15 years in the male and female victims, respectively. At admission, males were characterized by a higher hematocrit and higher serum levels of creatinine, BUN, potassium and phosphorus, while other clinical and laboratory parameters as well as the number of fasciotomized and amputated extremities did not differ between the two genders. Males suffered from longer periods of oliguria, higher rates of sepsis and hypertension. 77.3% of the male patients needed dialysis support as compared to 71.5% in the females. The number of hemodialysis sessions and days for dialysis support were higher in the males. Last serum creatinine before discharge from the nephrology clinics was higher in male victims, while mortality rates were similar in both genders. CONCLUSION: Although males are characterized by more severe laboratory abnormalities of rhabdomyolysis, more frequently suffer from sepsis and need more intensive dialysis support, gender is not a prognostic indicator of final outcome in the renal victims of disasters.

Adolescent↗

Hypervolemia in peritoneal dialysis patients.

This paper reviews the evaluation of volume status in peritoneal dialysis (PD) and the epidemiology of protocols assessing the hydration status in PD patients, in addition the factor contributing to fluid overload in PD patients, among them the peritoneal transport characteristics, being the most important, are discussed. Long term structural and functional alteration in the membrane occur which may affect the peritoneal ultrafiltration capacity. Finally, the most important therapeutic options to treat hypervolemia in PD patients are discussed, including dietary salt restriction, the prescription of loop diuretics and the application of low sodium dialysate and polyglucose solutions.

Hemodialysis Solutions↗

Relationship between fluid status and its management on acute renal failure (ARF) in intensive care unit (ICU) patients with sepsis: a prospective analysis.

BACKGROUND: Sepsis carries a high morbidity and mortality, further enhanced by acute renal failure (ARF). Although fluid loading can prevent ARF in dehydrated patients, this approach could be risky in septic patients, since it can deteriorate oxygenation. This study evaluates the relationship between fluid status and management and ARF development in septic patients. METHODS AND PATIENTS: Patients admitted to the ICU between 1 January 2001 and 31 December 2001 were included if serum creatinine (Cr) was <2 mg% on admission, and if they developed sepsis. ARF was determined as a doubling of serum Cr, an increase of serum Cr >2 mg%, or oliguria <500 ml/24 hr. RESULTS: 257 out of 2442 patients, admitted to the intensive care unit (ICU), developed sepsis, 29 developed ARF, 13 needed a renal replacement. ARF vs. non-ARF patients were older (65.2 +/- 13.3 vs. 55.1 +/- 17.4, p=0.002), had a higher central venous pressure (CVP) at day 1 (9.6 +/- 4.3 vs. 5.2 +/- 3.6 mmHg, p<0.001), and at day 2 (7.1 +/- 5.1 vs. 5.1 +/- 4.0 mmHg, p=0.03), a higher colloid fluid loading for the first 3 days (2037 +/- 1681 vs. 1116 +/- 1220 mL, p<0.03), a higher serum Cr (1.25 +/- 0.39 vs. 0.96 +/- 0.33 mg/dL, p=0.009) and an increase vs. a decrease in serum Cr during the first 24 hr (+0.30 +/- 0.58 vs. -0.31 +/- 0.45 mg/dL, p=0.02), a lower diuresis (1347 +/- 649 vs. 1849 +/- 916 mL, p=0.005). There was no difference in APACHE II scores (19.2 +/- 7.2 vs. 17.2 +/- 6.6, p=0.1), or MAP (64.5 +/- 12.4 vs. 67.9 +/- 12.4, p=0.18). The fraction of inspired oxygen (FiO2) need in the ARF group increased from 40.4 +/- 11.5 to 65.6 +/- 24.2% from day 1 to day 2 (p=0.04), where it remained unchanged in the non-ARF group. The use of diuretics was higher in the ARF group (21/29 vs. 43/228, p=0.001). CONCLUSION: Septic patients developing ARF have an elevated CVP at day 1 of sepsis, indicating cardiodepression or intrarenal causes for hypoperfusion. These patients develop ARF despite further fluid loading. Respiratory function deteriorated in patients with ARF. Persistent fluid challenges should be avoided if they do not lead to an improvement in renal function, or if oxygenation deteriorates.

APACHE↗