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R W van Olden

Publications and source records attributed to R W van Olden.

18 recordsLinked to original sources
PubMed2006

[Risks associated with parenteral treatment of acute agitation].

BACKGROUND: Acute agitation is a medical emergency requiring immediate intervention. However, treatment is a risky undertaking. AIM: To specify on the basis of a review of the literature: (1) the risks of (parenteral) interventions in psychiatric crisis situations; (2) to which antipsychotics these risks are linked; and (3) what precautionary measures and interventions are required. METHOD: A literature search was conducted using PubMed, using as key words: parenteral, antipsychotics, benzodiazepines, acute agitation, crisis intervention, and fatalities. RESULTS: Several parenteral antipsychotics are known to cause cardiotoxicity and/or hypotension. They can also induce acute movement disorders such as a laryngeal spasm. Benzodiazepines (parenteral) can lead to respiratory depression as a result of excessive sedation. CONCLUSION: Risks are associated with parenteral delivery of antipsychotics. These risks can be life-threatening. If an agitated patient needs to be given antipsychotics parenterally, the intervention should take place in surroundings where the patient can be adequately monitored and where the necessary facilities are available for dealing with life-threatening side effects.

Antipsychotic Agents↗
PubMed2000

Cardiac and hemodynamic effects of hemodialysis and ultrafiltration.

Imbalance between cardiac oxygen supply and demand may trigger cardiac events in already vulnerable hemodialysis (HD) patients. We studied the effect of ultrafiltration (UF) and HD in nine chronic HD patients by continuously measuring blood volume (BV; by Critline), blood pressure (BP; by Portapres), and changes in hemodynamics (Modelflow) during isolated UF (iUF) of 500 mL in 30 minutes and subsequent HD combined with UF (HD + UF). Aortic pressure was reconstructed from finger pressure. Changes in cardiac oxygen supply were assessed by calculating the area under the aortic pressure curve during diastole (diastolic pressure time index [DPTI]). Changes in cardiac oxygen demand were assessed by calculating systolic pressure time index (SPTI). BV decreased 4.0% +/- 1.8% during UF and 7.3% +/- 3.3% during HD + UF (both P < 0.01). Systolic BP did not change; diastolic and mean BP increased 11 +/- 7.4 and 11 +/- 8.4 mm Hg during iUF, respectively (both P < 0.01), and stabilized during HD + UF. Overall pulse pressure decreased 19 +/- 11.1 mm Hg (P < 0.01). Heart rate increased 13 +/- 11 beats/min (P < 0.01) and systemic vascular resistance increased 59% +/- 51% (P < 0. 01), whereas stroke volume and cardiac output (CO) decreased by 40% +/- 17% and 30% +/- 13%, respectively (both P < 0.01). Both cardiac oxygen supply (DPTI) and demand (SPTI) increased during iUF, and both decreased during HD + UF. By the end of the procedure, DPTI/SPTI ratio had increased 9% +/- 8% (P < 0.05). Changes in CO correlated closely to changes in BV. Despite large changes in hemodynamics during uncomplicated UF and HD, the balance between cardiac oxygen supply and demand (DPTI/SPTI ratio) did not decrease, but improved slightly.

Adult↗
PubMed1998

Augmenting solute clearance in peritoneal dialysis.

BACKGROUND: The removal of low molecular weight solutes by peritoneal dialysis is less than by hemodialysis. The targets for Kt/Vurea and creatinine clearance formulated in the Dialysis Outcome Quality Initiative are unlikely to be achieved in a substantial portion of peritoneal dialysis patients. Possibilities to increase small solute clearances have therefore been subject to many investigations. METHODS: A review of the literature and of recent new data on determinants of solute removal, such as residual renal function, the role of drained dialysate volume and manipulation of the diffusive capacity of the peritoneum are presented. RESULTS: The contribution of residual GFR is more important for the clearance of creatinine than for Kt/Vurea. It is even more important for the removal of organic acids that are removed from the body by tubular secretion. High dosages of furosemide increase the urinary volume and the fractional Na+ excretion, but have no effect on the magnitude of residual GFR, renal creatinine clearance, renal urea clearance, and peritoneal transport characteristics. The drained dialysate volume per day is the main determinant of the peritoneal removal of urea. Its effect decreases the higher the molecular weight of a solute. It can be augmented by using large instillation volumes, by the application of more exchanges, and by increasing peritoneal ultrafiltration. A large exchange volume is especially effective in patients with an average transport state, but in those with high solute transport rates, Kt/Vurea is especially influenced by the number of exchanges. Possibilities to increase ultrafiltration are discussed. The diffusive capacity of the peritoneum can be augmented by using low dosages of intraperitoneally administered nitroprusside. This increases solute transport most markedly when it is applied in combination with icodextrin as osmotic agent. CONCLUSIONS: Small solutes clearances cannot be increased by furosemide. Increasing the instilled volume of dialysis fluid and the number of exchanges both affect solute clearance. Studies are necessary on long-term effects of manipulation of the peritoneal membrane with nitroprusside.

Diffusion↗
PubMed1998

Cytokine filtration and adsorption during pre- and postdilution hemofiltration in four different membranes.

In the present in vitro study we investigated filtration and adsorption of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-8 (IL-8) during predilution and postdilution hemofiltration with polysulfone, polyacrylonitrile, polyamide and cellulose triacetate membranes. The median sieving coefficient (SC) for all membranes was 0.0 for TNF-alpha, below 0.15 for IL-6 and below 0.15 for IL-8 during postdilution hemofiltration. Differences in SC between filtration modes were less than 0.05. Maximal differences in SC between membranes were 0.11 for IL-6, 0.0 for TNF-alpha, and 0.11 for IL-8. The progressive decrease in cytokine concentrations was identical between the two filtration modes and most pronounced with the polyacrylonitrile membrane (reduction 77% for IL-6, 39% for TNF-alpha and 95% for IL-8 after 4 h of hemofiltration). The relative contribution of adsorption to the reduction in cytokines was 100% for TNF-alpha for all membranes, between 53 (cellulose triacetate) and 83% (polyacrylonitrile) for IL-6, and for IL-8 between 0 (polysulfone) and 100% (polyacrylonitrile). In conclusion, the reduction in TNF-alpha, IL-6 and IL-8 was most impressive with the polyacrylonitrile membrane after 4 h of hemofiltration and was largely due to adsorption. Adsorption of TNF-alpha, IL-6 and IL-8 was also seen with the other membranes. None of the membranes filtered TNF-alpha. Sieving of IL-6 and IL-8 was low for all membranes with only marginal differences between membranes or between filtration modes.

Acrylic Resins↗
PubMed1998

Elevated 24-hour blood pressure in peritoneal dialysis patients with ultrafiltration failure.

Many patients treated with peritoneal dialysis (PD) are overhydrated. We investigated whether hypertension in PD patients is related to ultrafiltration-failure-induced fluid retention. Twenty-four-hour blood pressure measurements were performed in 10 normotensive and 9 hypertensive PD patients, aged 20 to 77 years, and treated with PD for 2 to 125 months. Antihypertensive medication had been discontinued for 3 weeks. Twenty-four-hour blood pressure was monitored with a Spacelabs 90207. Mean 24-hour systolic, mean, and diastolic pressure were calculated, together with the nighttime (23:00-07:00)/daytime (07:00-23:00) ratio. Ultrafiltration was determined separately during a standardized 4-hour peritoneal permeability analysis (SPA) with 1.36% glucose. Based on the SPA, patients were divided into a group with negative net ultrafiltration (NUF) and a group with positive net ultrafiltration (PUF). In 8 patients with NUF, systolic, mean, and diastolic pressures were 142 +/- 16 mmHg, 110 +/- 14 mmHg, and 95 +/- 13 mmHg, compared to 135 +/- 22 (ns), 99 +/- 14 (ns), and 81 +/- 11 (P < 0.05) in 11 patients with PUF. Net ultrafiltration during the test dwell correlated negatively with diastolic blood pressure (r = -0.53, P < 0.05). Diurnal blood pressure variations were not related to ultrafiltration capacity. In conclusion, hypertension in PD patients may in part be explained by fluid retention caused by impaired ultrafiltration.

Adult↗
PubMed1998

Intracellular and extracellular blood magnesium fractions in hemodialysis patients; is the ionized fraction a measure of magnesium excess?

To establish the best measure for determining magnesium overload, we measured ionized and total magnesium in serum and mononuclear blood cells and total magnesium in erythrocytes in blood of 23 hemodialysis patients, known for their disturbed magnesium homeostasis. When comparing the mean magnesium values obtained in the patient population with those of a control population, all of these magnesium markers, including the biologically active fractions, were significantly (P < 0.05) increased. Because serum total magnesium was not increased in all dialysis patients studied, the population was divided into two groups, according to total serum magnesium > 1.0 mmol/L or less than that. Results in these two populations showed that ionized serum magnesium and ionized magnesium in mononuclear blood cells might give a better indication about the magnesium status of the tested patients than the currently used total serum magnesium data. However, neither of the two markers, especially ionized serum magnesium, was able to discriminate fully between normal magnesium homeostasis and magnesium excess. We therefore conclude that the two ionized magnesium markers offer minimal advantage for this discrimination, and that the total magnesium concentration in serum remains the measurement of choice.

Adult↗
PubMed1998

Contribution of tubular anion and cation secretion to residual renal function in chronic dialysis patients.

The clearance of organic ions by the tubules may contribute to the removal of uremic waste products in dialysis patients. The renal excretion of an exogenous anion p-aminohippurate (PAH) was investigated in 10 peritoneal dialysis patients and 10 hemodialysis patients during one clearance period and compared with the clearance of creatinine (Ccr) and inulin (CIn). The clearance period was 24 hours in the peritoneal dialysis patients and one interdialytic interval of 3 days divided in 4 parts [CPA-D] in hemodialysis patients. In peritoneal dialysis patients the renal clearance of total PAH (median 14.3 ml/min, range 3.8-33.0) exceeded the CIN (median 3.2 ml/min, range 1.6-11.2, p < 0.005) and Ccr (median 4.0 ml/min, range 1.7-15.0, p < 0.005). A positive correlation was found between the tubular clearances of creatinine (cationic pathway) and of total PAH (anionic pathway, r: 0.72, p <0.02). In hemodialysis patients the clearance of total PAH (CPA: median 2.0, range 0.8-9.6; CPD: median 3.8, range 1.7-15.4) also exceeded the clearance of inulin (CPA: median 1.5, range 0.2-3.4; CPD: median 2.7, range 0.9-4.4) in the beginning and the end of the interdialytic interval (p < 0.005). The CIN and the clearance of total PAH increased during the interdialytic interval, but the Ccr (CPA: median 2.2, range 0.4-8.9, CPD: median 2.9, range 1.2-4.6) remained stable. Thus, the change in tubular clearance of creatinine and PAH was opposite during the interdialytic interval: it increased for total PAH and decreased for creatinine. The CTPAH/CIN ratio in hemodialysis patients was lower than in peritoneal dialysis patients. In CPA it was median 1.6 (range 1.1-5.6, p < 0.05) and in CPD it was median 1.7 (range 1.1-5.0, p < 0.02) and in the peritoneal dialysis patients it was median 3.6 (range 1.5-9.1). We conclude that tubular clearances contribute to the residual renal function in dialysis patients, but the tubular handling of anions and cations in relation to the residual GFR is different between peritoneal and hemodialysis patients. A difference in clearance of organic acids caused by the dialysis techniques may be an explanation for the differences in clinical outcome between the two dialysis modalities.

Adult↗
PubMed1997

Predicting mortality in intensive care patients with acute renal failure treated with dialysis.

Existing prognostic methods were compared in their ability to predict mortality in intensive care unit (ICU) patients on dialysis for acute renal failure (ARF). The clinical goal of this study was to determine whether these models could identify a group of patients where dialysis would provide no benefit because of a near 100% certainty of death even with dialysis treatment. This retrospective cohort study included 238 adult patients who received a first dialysis treatment for ARF in the ICU. This study examined the performance of seven general ICU mortality prediction models and four mortality prediction models developed for patients with ARF. These models were assessed for their ability to discriminate mortality form survival and for their ability to calibrate the observed mortality rate with the expected mortality rate. The observed in hospital mortality was 76% for our patient group. Areas under the receiver operating characteristic curve ranged from 0.50 to 0.78. With the Acute Physiology and Chronic Health Evaluation (APACHE) III and the Liano models, the observed mortality in the highest quintiles of risk were 97% and 98%. In conclusion, although none of the models examined in this study showed excellent discrimination between those patients who died in hospital and those who did not, some models (APACHE III, Liano) were able to identify a group of patients with a near 100% chance of mortality. This indicates that these models may have some use in supporting the decision not to initiate dialysis in a subgroup of patients.

Acute Kidney Injury↗
PubMed1996

Measurement of residual renal function in patients treated with continuous ambulatory peritoneal dialysis.

Renal function contributes markedly to the adequacy of continuous ambulatory peritoneal dialysis (CAPD). The best way to measure it in clinical practice has not been established. Ten stable CAPD patients with residual renal function were investigated to compare the GFR measured as inulin clearance (Cli) with the creatinine clearance (Clc), the urea clearance (Clu), and with 0.5(Clc + Clu). Thereafter, an analysis of whether the administration of cimetidine could improve the accuracy of these clearances was performed. Two clearance periods (CP) of 24 h were investigated. During CP-2, patients received 400 mg cimetidine twice daily, for a total dose of 1200 mg. Two h before the urine and dialysate collection period, inulin was administered iv. Calculations were done for each CP for Cli, Clc, Clu, Clc-Cli, the Clc/Cli ratio, and the tubular secretion of creatinine (TSc). No differences between CP-1 and CP-2 were present for urinary excretion of volume and solutes, and clearance rates of inulin and urea. The median TSc decreased from 0.71 mumol/min (range, -0.24 to 5.90) in CP-1 to 0.30 mumol/min (range, -0.18 to 0.64) in CP-2 (P < 0.05). Therefore, the median ratio of Clc/Cli decreased from 1.23 (range, 0.87 to 2.20) in CP-1 to 1.11 (range, 0.95 to 1.51) in CP-2 (P < 0.05). The median overestimation of the Cli in CP-1 by the Clc was 0.90 mL/min (range, -0.28 to 3.80) and by the 0.5(Clc + Clu) was 0.30 (range, -0.67 to 1.52). The median overestimation of Cli during cimetidine treatment in CP-2 was 0.43 mL/min (range, -0.21 to 1.20). The range, in differences between Cli and Clc, in CP-2 was smaller than that between Cli and 0.5(Clc + Clu) in CP-1. The difference between the clearance rate of inulin and creatinine or the combined clearance rate of urea and creatinine was not influenced by the magnitude of the average GFR. It can be concluded that the administration of cimetidine improved the accuracy of measuring the GFR with the Clc in CAPD patients.

Adult↗
PubMed1996

Similarities in functional state of the kidney in patients treated with CAPD and hemodialysis.

Differences have been reported in the decline of residual renal function in patients on continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD), but it is unknown whether the urinary handling of water and solutes is similar in these patient groups. Ten CAPD patients with residual renal function were investigated during a clearance period (CP) of 24 hours, and 11 HD patients were investigated during one interdialytic interval of three days. In CAPD patients the urinary volume excretion was 0.65 +/- 0.31 mL/min (mean +/- SD), and the inulin clearance was 3.85 +/- 2.82 mL/min. A negative correlation was found between the peritoneal net ultrafiltration rate and both the urinary volume excretion rate (r = -0.80, p < 0.01) and the fractional sodium clearance (r = -0.69, p < 0.05). In HD patients the urinary volume excretion increased from 0.36 +/- 0.36 mL/min during the initial eight hours of CP (HD-A) to 0.64 +/- 0.29 mL/min during the last ten hours of CP (HD-D, p < 0.05), and the inulin clearance increased from 1.9 +/- 1.3 (HD-A) to 2.9 +/- 1.1 (HD-D, p < 0.005). The fractional sodium clearance increased from 8.5 +/- 5.7% (HD-A) to 14.4 +/- 9.0% (HD-D, p < 0.05). It can be concluded that the fractional excretion of volume and fractional clearance of solutes were similar in patients treated with CAPD and hemodialysis. The most important regulating factor seems to be the volume status influenced by volume removal by peritoneal net ultrafiltration in CAPD patients, and volume expansion during the interdialytic interval in hemodialysis patients.

Adult↗
PubMed1995

Sensitivity of residual nephrons to high dose furosemide described by diuretic efficiency.

Ten haemodialysis (HD) patients with a median residual creatinine clearance (CLCR) of 1.9 ml.min-1 x 1.73 m-2 (range 0.6-5.3) were treated with oral furosemide (F) 2.0 g. Overall-efficiency (O-E, daily sodium excretion/total urinary F) and total-efficiency (delta-E, increase in daily sodium excretion/total urinary F) were measured on the last 24 hours of each interdialysis interval. In addition, O-E was measured during the complete interdialysis interval in 10 HD patients with a median CLCR of 5.6 ml.min-1 x 1.73 m-2 (range 0.7-6.8) treated for 1 year with a fixed oral dose of F between 250-1000 mg (median 625 mg). In the short study the median O-E was 10.6 mmol.mg-1 (range 1.9-22.0) and delta-E 6.2 mmol.mg-1 (range 1.3-11.2). The fractional excretion of sodium FENa was significantly increased from 9.6% (range 4.1-22.9) to 27% (range 14.6-56.2) during F treatment. A positive correlation was found between the basal FENa and delta-E. In the long-term study median O-E was 6.4 mmol.mg-1. O-E and FENa showed no change over time although median RCC decreased from 5.6 to 1.9 ml.min-1 x 1.73 m-2 and median F excretion from 11.8 to 7.5 mg per day. It can be concluded that diuretic efficiency in haemodialysis patients is dependent on FENa and the state of hydration during the interdialysis interval.

Aged↗
PubMed1995

Time course of inulin and creatinine clearance in the interval between two haemodialysis treatments.

BACKGROUND: Urinary volume of haemodialysis patients with residual renal function increases during the interdialytic interval. The contribution of GFR to this change in water and solute excretion has not been quantified in detail. The creatinine clearance (Clc) as a determinant of the GFR may overestimate GFR caused by the tubular secretion of creatinine. Cimetidine has been used to inhibit the secretion of creatinine in non-dialysed patients. No data are available on its usefulness in haemodialysis patients. METHODS: Two identical interdialytic intervals (DI) of 3 days (DI-1, DI-2) were investigated in 11 patients. The interval between DI-1 and DI-2 was 1 week. During DI-2 cimetidine 800 mg daily was administered. Each DI was divided in four urine-collection periods. RESULTS: The water and solute excretion in DI-1 and DI-2 were similar. Urinary production increased from 0.37 +/- 0.30 ml/min to 0.66 +/- 0.33 ml/min (P < 0.05), inulin clearance (Cli) increased from 1.8 +/- 1.1 ml/min to 2.7 +/- 1.2 ml/min (P < 0.05), fractional sodium excretion from 9.0 +/- 5.7% to 14.5 +/- 9.0% (P < 0.05). In contrast to Cli the Clc showed no increase during the interdialytic interval both in DI-1 and DI-2. The overestimation of GFR by creatinine (Clc-Cli) decreased during DI-1 from 1.35 +/- 1.69 ml/min to 0.26 +/- 0.60 (P < 0.05) and during DI-2 from 1.01 +/- 1.33 ml/min to 0.10 +/- 0.67 (P < 0.01). The ratio Clc/Cli decreased during DI-1 from 1.78 +/- 0.53 to 1.09 +/- 0.19 (P < 0.01) and during DI-2 from 2.02 +/- 1.13 to 1.05 +/- 0.30 (P < 0.01). All parameters were not different between the comparable days of DI-1 and DI-2. CONCLUSION: We conclude that the urinary volume in the interdialytic interval is directly related to changes in GFR. During the interdialytic interval GFR increased and tubular secretion of creatinine decreased. The administration of cimetidine did not improve the accuracy of Clc as a measurement of GFR in end-stage renal failure.

Adult↗
PubMed1992

Acute and long-term effects of therapy with high-dose furosemide in chronic hemodialysis patients.

The effects of daily administration of 250-2,000 mg furosemide (F) were studied in patients on hemodialysis who still had residual renal function. In a short study, 10 patients (endogenous creatinine clearance 0.6-5.3 ml/min/1.73 m2) used 1,000 mg F twice daily during 7 days, and in a long-term study 13 patients (endogenous creatinine clearance 0.7-6.8 ml/min/1.73 m2) were treated during 1 year with 250-1,000 mg F orally each day. In the short study, we observed an increase in the 24-hour volume excretion with a median of 109% (p < 0.005). Urinary sodium excretion increased 210%, chloride 346% and potassium 65% when compared with the control period. In the long-term study, a marked initial rise in diuresis and electrolyte excretion was found. However, during a 1-year follow-up, a gradual decrease in response with time was found caused by progression of renal disease. There were no signs of ototoxicity. Side effects were bollous dermatosis on the limbs after exposure to sunlight during the summer (3 patients). We conclude that high-dose F is effective in patients on hemodialysis with residual urinary production. However, in the long term, the diuretic effects diminish because of progression of the underlying renal disease.

Aged↗
PubMed1989

[Chyluria caused by congenital retroperitoneal lymphangiectasis].

A Dutch woman with non-parasitic chyluria is described. Lymphangiography and abdominal CT demonstrated retroperitoneal lymphangiectasis, dilated and tortuous lymphatic ducts around the right pyelocaliceal system and contrast in the bladder. The thoracic duct was patient. There were no metabolic or immunological abnormalities. The aetiology was probably congenital malformation of the lymphatic system. The treatment was conservative.

Adult↗
PubMed1989

[Terminal kidney insufficiency caused by disseminated cholesterol emboli as a complication of intra-arterial manipulation].

Following a renal PTA a 63-year-old man developed a multisystem illness caused by disseminated cholesterol embolism. The clinical manifestations were changing myalgia, peripheral ischaemia, livedo reticularis, episodic hypertension, eosinophilia and rapidly progressive renal insufficiency. The diagnosis was made on the clinical picture and confirmed by skin biopsy. Ultimately, chronic intermittent haemodialysis was necessary. There is no specific treatment available for this disease. It is possible that this complication occurs more frequently, but often remains subclinical.

Acute Kidney Injury↗
PubMedDate not supplied

IgG subclasses in CAPD patients.

OBJECTIVE: To make a comparison of serum levels of immunoglobulin G (IgG) subclasses in adult continuous ambulatory peritoneal dialysis (CAPD) patients with those in age- and sex-matched hemodialysis patients and healthy volunteers, and to analyze the contribution of removal of these proteins in peritoneal effluent to their plasma values. DESIGN: A cross-sectional study. SETTING: A renal unit of a university hospital. PATIENTS: Twenty-three CAPD patients, 21 hemodialysis patients, and 21 healthy volunteers. Peritoneal transport studies were done in 8 of the 23 CAPD patients. METHODS: IgG subclasses were measured in serum by nephelometry. For the peritoneal transport studies an ELISA method on ethylenediamine tetracetic acid plasma was used. The same method was used in seven-to-ten-fold concentrated peritoneal dialysate. RESULTS: CAPD patients had lower IgG2 and IgG4 levels than hemodialysis patients and healthy volunteers (p < 0.01). IgG2 values below 1.5 g/L were present in 43% of the CAPD patients (p < 0.001 compared to healthy volunteers). Peritonitis incidence was not different between CAPD patients with low or normal IgG2 plasma levels. Peritoneal clearance of IgG3 was lower than that of the other subclasses. Evidence was obtained for a depressed synthesis of IgG2 and IgG4 in CAPD patients. The hypothesis that interleukin-2 may be involved in the low synthesis rate of IgG2 is discussed. CONCLUSION: Low serum IgG2 and IgG4 levels are present in stable, adult CAPD patients. These were not caused by increased peritoneal loss, but by decreased synthesis.

Adult↗