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W J Kox

Publications and source records attributed to W J Kox.

At least 55 records · Page 3Linked to original sources
PubMed2001

Influence of aminosteroid and glucocorticoid treatment on inflammation and immune function during cardiopulmonary bypass.

OBJECTIVE: During cardiopulmonary bypass, inflammation and immunosuppression is present. We measured circulating mediators and monocyte-based functions and tested the hypothesis that these variables are influenced by methylprednisolone (MP) or tirilazad mesylate (TM) treatment. DESIGN: Randomized, controlled, double-blind prospective trial. SETTING: A university hospital. PATIENTS: Thirty-nine patients scheduled for conventional coronary surgery with three-vessel disease. INTERVENTIONS: Preoperative application of MP (15 mg/kg) or TM (10 mg/kg) compared with placebo (PL). MEASUREMENTS AND MAIN RESULTS: Circulating proinflammatory markers including interleukin (IL)-6, IL-8, monocyte chemoattractant protein 1, and C-reactive protein were all decreased by MP treatment but not by TM treatment. Whereas rapid increases in circulating anti-inflammatory IL-10 were superinduced by MP but not TM, plasma levels of IL-1RA and transforming growth factor beta were not altered by either treatment. Decreased ex vivo lipopolysaccharide-stimulated secretion of tumor necrosis factor alpha was prolonged after MP treatment but not after TM treatment. Perioperative stimulated secretion of IL-12 and interferon gamma was diminished in all groups, whereas ex vivo IL-1RA secretion tended to increase in all groups. Depression of monocyte surface expression of HLA-DR was significantly greater in patients treated with MP, whereas CD14 expression did not change. CONCLUSIONS: These data confirm that, during cardiopulmonary bypass, pro- and anti-inflammatory systems are activated at the same time, whereas monocyte-based immune functions are depressed. Treatment with MP abrogates proinflammatory mediators and induces a shift toward anti-inflammation at the cost of further functional monocyte deficits, whereas treatment with TM apparently has neither anti-inflammatory nor immunosuppressive actions in this setting.

Antioxidants↗
PubMed2001

The value of immune modulating parameters in predicting the progression from peritonitis to septic shock.

Intra-abdominal infection is one of the major causes of septic shock and multiple organ failure. To date, what causes the disease's progression remains unclear and therefore the relevance of immune modulating therapies remains speculative. The primary outcome measure of this study was to investigate immune modulating mediators at the onset of peritonitis before the development of subsequent septic shock. The secondary outcome measure was to investigate the usefulness of these immune parameters in predicting progression from peritonitis to septic shock. Fifty-eight peritonitis patients were included in this study: 14 patients subsequently developed septic shock. All patients were examined on "diagnosis of peritonitis" (<4 h within establishment of diagnosis), during "early septic shock" (<12 h following the onset of septic shock), and once again during "late septic shock" (within 72-98 h following the onset of septic shock). The immune modulating parameters tumor necrosis factor-alpha (TNF-alpha), the soluble TNF-alpha receptors I and II (sTNF-alpha RI and sTNF-alpha RII), interleukines (IL) -1beta, -6, -8, and -10, and the adhesions molecules endothelial-leukocyte-adhesion-molecule (E-Selectin), intercellular-adhesion-molecule-1 (ICAM-1), and vascular-adhesion-molecule-1 (VCAM-1), in addition to nitrate and nitrite, were determined. In the peritonitis group with subsequent septic shock, TNF-alpha, sTNF-alpha RI + RII IL-1beta, IL-8, IL-10, and nitrate were significantly increased before the onset of septic shock. TNF-alpha had an area under the receiver operating characteristics curve (AUC) of 0.84 and was reliable in predicting the progression from peritonitis to septic shock. The AUC of the other immune modulating parameters, despite being significantly elevated, ranged from 0.71 to 0.76. The AUC of the conventional laboratory markers such as leukocytes and C-reactive protein ranged from 0.64 to 0.68. In peritonitis that progressed to septic shock, an early immune response had already occurred before the onset of septic shock. The progression was best predicted by TNF-alpha. Therefore, mediator therapy might be considered in high-risk peritonitis patients who show an exaggerated immune response before the progression to septic shock.

Adult↗
PubMed2001

Effects of alcohol on the heart.

Some evidence suggests that light to moderate alcohol consumption protects against cardiovascular diseases. However, this cardioprotective effect of alcohol consumption in adults is absent at the population level. Approximately 20 to 30% of patients admitted to a hospital are alcohol abusers. In medical practice, it is essential that patients' levels of consumption are known because of the many adverse effects that might result in the course of routine care. Ethanol damage to the heart is evident if alcohol consumption exceeds 90 to 100 g/d. Heavy ethanol consumption leads to increased risk for sudden cardiac death and cardiac arrhythmias. In patients with coronary heart disease, alcohol use was associated with increased mortality. An early response to drinking was an increased ventricular wall thickness to diameter ratio, possibly proceeding with continuous drinking to alcoholic cardiomyopathy, which had a worse outcome compared with idiopathic dilative cardiomyopathy if drinking was not stopped or at least reduced (< 60 g/d). In the ICU, patients with chronic alcoholism have more cardiac complications postoperatively. These complications probably are caused by biventricular dysfunction, particularly with the occurrence of severe infections or septic shock, events that are three to four times more frequent among chronic alcoholics than occasional drinkers or nondrinkers. To prevent further complications from drinking and for long-term management of drinking, patients with alcohol abuse and heart failure should be treated in brief intervention and follow-up programs. Prognosis is good even in patients with New York Heart Association class IV heart failure caused by cardiomyopathy if complete abstinence is accomplished. Noncompliance to smoking and alcohol restrictions, which are amenable to change, dramatically increases the risk for hospital readmissions among patients with heart failure.

Alcohol Drinking↗
PubMed2001

Increased endothelial injury in septic patients with coronary artery disease.

STUDY OBJECTIVE: Recently, it was proposed that soluble intercellular adhesion molecule (sICAM)-1 plasma levels may allow subgroup identification of patients at risk for cardiovascular complications during sepsis. However, the impact of preexisting coronary artery disease (CAD) on these results has not yet been tested. The aim of this study was to investigate whether plasma levels of adhesion molecules, nitric oxide, and cytokines differ between septic patients with or without preexisting CAD. DESIGN: Prospective study. SETTING: Surgical ICU. PATIENTS: Forty-four septic patients, 24 of whom met the criteria of CAD. MEASUREMENT: Hemodynamic measurements were performed and blood samples were taken within 12 h after onset of sepsis (early sepsis) and again 72 h thereafter (late sepsis). Soluble adhesion molecules and cytokines were determined using commercially available enzyme-linked immunosorbent assay kits, cyclic guanosinomonophosphate (cGMP) by competitive radioimmunoassay, and nitrite/nitrate photometrically by Griess reaction. RESULTS: In CAD patients, sICAM-1 (p < 0.02) was significantly elevated in early and late sepsis, whereas soluble endothelial-linked adhesion molecule (sE-selectin; p < 0.01) and cGMP (p < 0.03) were only increased in late sepsis. Oxygen consumption did not significantly differ between groups. Oxygen delivery and mixed venous oxygen saturation during early and late sepsis were significantly diminished and the oxygen extraction ratio significantly increased in the CAD group (p < 0.05). CONCLUSIONS: Increased endothelial injury may be indicated by the elevated levels of sICAM-1, sE-selectin, and cGMP in septic patients with preexisting CAD. These parameters, however, failed to serve as predictors for unknown CAD or chances for survival in early sepsis.

Case-Control Studies↗
PubMed2001

Renal replacement therapy: physical properties of hollow fibers influence efficiency.

INTRODUCTION: Physical properties of filters for continous renal replacement therapy have a great impact on biocompatibility. According to Poiseuille's law, a filter with more and shorter hollow fibers should offer a decreased pressure drop and, therefore, lower transmembrane pressure (TMP). The aim of this study was to study the effect of a new filter configuration in terms of TMP and clotting compared with the standard configuration. METHODS: In a prospective randomized cross-over study 2 polysulphone hollow fiber hemofilters, one handmade, which differed only in length and number of hollow fibers were compared. In each group 12 filters were investigated during continous venovenous hemofiltration in patients with acute renal failure due to septic shock. Pressures were measured every 3 hours and running time until filter clotting was documented. Mediators before and after the filter, at the end of treatment and in filtrate were assessed. RESULTS: The standard filter with longer hollow fibers had significantly lower TMPs (106 vs. 194 mmHg, p=0.02) and longer running times (1276 vs. 851 min, p=0.04). There were no differences in hematocrit, total protein, cellular and plasmatic coagulation or blood temperature. No significant elimination of mediators was shown. CONCLUSION: In contrast to our expectations, the filter with the longer hollow fibers had a better performance, as it ran longer and had lower TMP This may be due to slower blood flow leading to an increase in blood viscosity in a filter with a larger cross section.

Acute Kidney Injury↗
PubMed2000

Endothelium function in sepsis.

Endothelial cells can be the prime target for an infection and infected endothelial cells may serve as an initiating system for a systemic response as these cells are able to secrete many mediators known to be of paramount importance. Endothelial cell functions in turn are regulated by these circulating mediators. Cellular interactions with leukocytes revealed protective and destructive functions. Single cell and animal studies indicate that endothelial permeability is increased and apart from clinical obvious edema formation in septic patients, the endothelial component remains unknown. Endothelial coagulation activation has been shown in vitro, however human data supporting an endothelial procoagulatory state are lacking. Defects in endothelium dependent vasoregulation in animal models are well known and again human studies are largely missing. An imbalanced production of reactive oxygen species including nitric oxide has been found to be involved in all endothelial functions and may provide a common link which at present can be supported only in animal studies.

Animals↗
PubMed2000

Effects of the stable prostacyclin analogue iloprost on the plasma disappearance rate of indocyanine green in human septic shock.

OBJECTIVES: To evaluate the effect of the stable prostacyclin analogue iloprost on the plasma disappearance rate of indocyanine green (PDR) in patients with septic shock. DESIGN AND SETTING: A prospective clinical study in a university hospital intensive care unit. PATIENTS AND INTERVENTIONS: 20 patients in septic shock. Patients received iloprost infusion (1 ng/kg per minute) for 24 h. MEASUREMENTS AND RESULTS: PDR was determined by a femoral arterial fiberoptic catheter before, 1, 6, and 24 h after start and 1 h after end of iloprost infusion. PDR increased significantly 24 h after start of iloprost infusion (baseline: 13.9 +/- 1.7% vs. 18.6 +/- 2.2%/min) and decreased 1 h after end of infusion (13.7 +/- 1.7%/min; p < 0.002). There was no change in pHi, cardiac index, mean arterial pressure, heart rate, central venous pressure, or intrathoracic blood volume index. CONCLUSION: Administration of the stable prostacyclin analogue iloprost significantly increases PDR, indicating improvement in liver function.

Adult↗
PubMed2000

Immunomodulatory therapies in sepsis.

Despite advances in critical care medicine, mortality from sepsis in ICU patients remains high. In response to several infectious and non-infectious stimuli, monocytes/ macrophages release a number of mediators, including cytokines, involved in the proinflammatory response that underlies sepsis. The excessive release of these mediators results in the development of whole body inflammation, and plays an important role in the pathogenesis of sepsis and septic shock. In addition, patients with sepsis also undergo an anti-inflammatory phase (the compensatory anti-inflammatory response syndrome) and at times, a mixed response with both pro-and anti-inflammatory components (the mixed antagonistic response syndrome). The initial systemic hyperinflammation is caused by production of inflammatory cytokines, especially tumour necrosis factor-a (TNF-alpha), and also interleukin-1 (IL-1), IL-6, and interferon gamma, which act synergistically with TNF-alpha in inducing shock in animal models. However, clinical trials aimed at downregulating these mediators using antibodies against endotoxin, TNF-alpha, antagonists of IL-1 or platelet activating factor have proved to be uniformly disappointing. Not only have these agents been found to have no effect, but they may also increase mortality. One of the reasons for such failure may be the lack of precise immunological monitoring during the course of sepsis. We have recently demonstrated that sepsis shows a biphasic immunological pattern during the initial and later phase: the early hyperinflammatory phase is counterbalanced by an anti-inflammatory response which may lead to a hypoinflammatory state. The latter is associated with immunodeficiency that is characterised by monocytic deactivation, so-called immunoparalysis. Interferon gamma-1 b has an immunoregulatory effect in patients with immunoparalysis during the compensatory anti-inflammatory response syndrome, not only restoring levels of HLA-DR expression but also reestablishing the ability of monocytes to secrete cytokines such as TNF-alpha. By monitoring immune status in septic patients, targeted intervention may lead to more success in immunomodulation of sepsis.

Animals↗
PubMed2000

Secretion of MCP-1 and IL-6 by cytokine stimulated production of reactive oxygen species in endothelial cells.

Endothelial cells are known to produce reactive oxygen species by several mechanisms. Functional consequences of increased production of reactive oxygen species were investigated in vitro after stimulation with several proinflammatory cytokines. Time dependent increases in DCF-fluorescence as a measure of reactive oxygen load were quantified in single cells after incubation with TNF-alpha, IL-1 and IFN-gamma. The increased DCF-fluorescence was inhibited by cell permeant antioxidative substances Tiron and Tempol. NMMA, an inhibitor of nitric oxide synthase reduced endothelial DCF-fluorescence only marginally, indicating a minor participation of nitric oxide production in this detection system. Cytokine induced endothelial DCF-fluorescence increased in the presence of NADH, whereas coincubation with NADPH or xanthine was without effect. Flavoenzyme inhibitor diphenyliodonium abolished stimulated DCF-fluorescence. Cytokine induced release of MCP-1 and IL-6 by endothelial cells was completely inhibited in the presence of Tiron and Tempol, whereas NMMA was less effective. Collectively these data indicate that cytokine stimulated endothelial cells increase their reactive oxygen species production probably via NADH oxidase and this production may critically be involved in the secretion of MCP-1 and IL-6.

Antioxidants↗
PubMed2000

Safety, efficacy, and long-term results of a modified version of rapid opiate detoxification under general anaesthesia: a prospective study in methadone, heroin, codeine and morphine addicts.

BACKGROUND: In the present study a method of rapid opiate detoxification under general anaesthesia has been evaluated regarding the safety, the efficacy in preventing withdrawal symptoms, and the long-term results. In addition, it was investigated whether the profile and severity of withdrawal symptoms depend on the type of opiate abused (methadone, heroin, codeine, morphine). METHODS: Seventy-two opiate addicts were detoxified in an intensive care unit (ICU). Anaesthesia was induced and maintained using propofol infusion. Patients were endotracheally intubated. The opiate receptor antagonist naltrexon was administered into the stomach via a nasogastric tube. Withdrawal symptoms before and after the detoxification treatment were assessed using an objective and a subjective opiate withdrawal scale (OOWS, SOWS). After detoxification patients entered a long-term naltrexone maintenance programme as well as a supportive psychotherapy programme. Vital organ function was monitored using haemodynamic and respiratory parameters as well as body temperature. RESULTS: Organ function parameters were stable during the whole treatment in all patients and no anaesthetic complications were registered. Minor side effects such as bradycardia or hypotension were observed in 20 patients. Compared to patients with pre-existing heroin, codeine, or morphine abuse respectively, patients from the methadone maintenance programme had significantly higher (P<0.01) OOWS as well as SOWS values after the treatment. Twelve months after the detoxification 49 patients (68%) were abstinent from opiates whereas 17 patients had relapsed during the period of follow-up. Six patients were lost during follow-up. CONCLUSIONS: Rapid opiate detoxification under general anaesthesia is a safe and efficient method to suppress withdrawal symptoms. This treatment may be of benefit in patients who particularly suffer from severe withdrawal symptoms during detoxification and who have failed repeatedly to complete conventional withdrawal. Methadone patients have more withdrawal symptoms than other opiate addicts.

Adult↗
PubMed2000

EEG controlled rapid opioid withdrawal under general anaesthesia.

We performed rapid opioid detoxification under propofol anaesthesia in 30 opioid addicts, using the opioid receptor antagonist naltrexone. Two strategies to obtain a sufficient depth of anaesthesia and to avoid anaesthetic overdose were evaluated. Patients were allocated randomly to one of two groups. In group 1, the effects of propofol were monitored by observing clinical signs, and in group 2, depth of anaesthesia was controlled using an EEG threshold method. Withdrawal symptoms and post-anaesthetic recovery time were assessed. All patients remained stable and no anaesthetic complications were noted. There were significant differences in the total dose of propofol given (group 1, mean 72 (SD 9) mg kg-1; group 2, 63 (8) mg kg-1; P < 0.01), duration of anaesthesia (318 (53) min vs 309 (42) min; P < 0.05), duration of recovery time (49 (13) min vs 40 (12) min; P < 0.01) and frequency of withdrawal symptoms between groups. In addition, the incidence of side effects was different between groups (62 vs 29 points on a withdrawal symptom scale; P < 0.01). To obtain a sufficient depth of anaesthesia but to avoid inappropriately large doses of anaesthetic, we consider that EEG monitoring is valuable during rapid opioid detoxification.

Anesthesia, General↗
PubMed2000

The pharmacokinetics and analgesic efficacy of larger dose rectal acetaminophen (40 mg/kg) in adults: a double-blinded, randomized study.

UNLABELLED: Analgesic acetaminophen plasma concentrations are not known. We investigated in a randomized, double-blinded study the pharmacokinetics and analgesic efficacy of small- (AS; 20 mg. kg(-1)) and larger- (AL; 40 mg/kg) dose rectal acetaminophen and compared it with the combination (C) of rectal diclofenac (100 mg) and acetaminophen (20 mg/kg) in 65 women undergoing hysterectomy. Suppositories were administered after the induction of a standardized general anesthesia. Pain (measured by using a 10-cm visual analog scale) and morphine consumption (patient-controlled analgesia) were repeatedly assessed for 24 h. Acetaminophen plasma concentrations were measured by using a fluorescence polarization immunoassay. Antipyretic plasma concentrations (10-20 mg/L) after 40 mg/kg acetaminophen were not associated with improved analgesia or decreased opioid requirements; 20 mg/kg acetaminophen produced subtherapeutic plasma levels (<10 mg/L). Maximal plasma concentrations of 17.2 and 10.4 mg/L (P < 0.01, analysis of variance) were achieved after 4.2 and 3.6 h for the AL and AS groups, respectively. The only difference in clinical outcome was lower visual analog scale scores after acetaminophen/diclofenac (C 2.0 versus AS 3.2 and AL 3.4) 4 h after the induction (P < 0.05, analysis of variance). Acetaminophen pharmacokinetics in adults were similar to those observed in children. Analgesic plasma concentrations are likely to be higher than antipyretic plasma levels, which were only attained after twice the recommended rectal dose was administered. Analgesic plasma concentrations have yet to be determined but may be higher than those associated with antipyresis. IMPLICATIONS: Acetaminophen pharmacokinetics were comparable in adults and children. Plasma concentrations known to reduce fever did not produce better pain relief and were only achieved after twice the conventional dose was administered. Analgesic plasma concentrations have yet to be determined but may be higher than those associated with antipyresis.

Acetaminophen↗
PubMed2000

Heparin induces release of phospholipase A(2) into the splanchnic circulation.

UNLABELLED: Cardiopulmonary bypass results in increased plasma activity of phospholipase A(2) (PLA(2)) that appears to be caused by the administration of heparin. High PLA(2) activity may be responsible for increased production of eicosanoids and, thus, may be implicated in various pathophysiologic events associated with cardiac surgery. To investigate the site of PLA(2) secretion, blood samples were simultaneously collected from the radial artery, the pulmonary artery, and the hepatic vein at 2, 4, 6, and 20 min after systemic heparinization (350 U/kg). Within 2 min of the heparin injection, plasma activity of PLA(2) increased 4- to 9-fold and remained so for at least 20 min. Two minutes after the heparin injection, PLA(2) was significantly higher in the hepatic vein than in the radial artery (P: < 0.01). No such difference was detected between pulmonary and radial arteries. When heparin was added to blood samples in vitro (5-100 U/mL), plasma activity of PLA(2) did not increase, which suggests that the enzyme was not secreted by blood cells. IMPLICATIONS: Heparin, given in the dosage required for cardiopulmonary bypass, caused release of phospholipase A(2) into the splanchnic circulation.

Aged↗
PubMed2000

Influence of heparin and hirudin on endothelial binding of antithrombin in experimental thrombinemia.

OBJECTIVE: During the last decade, experimental and clinical evidence has accumulated that antithrombin (AT) exerts anti-inflammatory effects when given in high doses. Meanwhile, AT substitution has been shown to significantly increase prostacyclin release. However, the link between endothelial AT binding and anti-inflammatory AT effects remains to be established in vivo, although heparin has been shown to counteract anti-inflammatory AT effects. We hypothesized that the administration of heparin in endotoxin-challenged rats would decrease endothelial AT binding and systemic prostacyclin concentrations. DESIGN: Prospective, randomized, controlled experimental in vivo study. SETTING: Research laboratory of a university hospital. ANIMALS: Fifty-six Wistar rats. INTERVENTIONS: Baseline values of coagulation variables were measured in six animals. Forty of 50 Wistar rats in the study groups were given endotoxin (50 mg x kg(-1) iv) and were treated with saline (group LPS), AT (15 units x kg(-1) x hr(-1)) (LPS+AT), AT and heparin (80 IU x kg(-1) x hr(-1)), or AT and hirudin (0.12 mg x kg(-1) x hr(-1)); the other 10 received saline instead of endotoxin and were treated with AT alone. Before endotoxin application, a tracheostomy was performed, and venous and arterial catheters were inserted for blood sampling and infusion. MEASUREMENTS: Intravital endothelial AT binding was studied by using fluorescence isothiocyanate-marked antibodies during intravital microscopy of intestinal submucosal venules. Systemic prostacyclin, thrombin-AT complex, and fibrinogen concentrations were measured after 4 hrs. Intergroup differences were tested by Kruskal-Wallis analysis of variance on ranks. MAIN RESULTS: AT and AT + heparin were equally effective in inhibiting systemic procoagulant turnover as reflected by fibrinogen concentrations. Only the administration of AT + hirudin significantly prevented fibrinogen consumption (p < .05). In contrast with all other treatments, the administration of heparin significantly reduced intravital endothelial AT binding (p < .05). However, prostacyclin concentrations were similarly increased in all endotoxin-challenged study groups irrespective of the anticoagulatory treatment. CONCLUSIONS: There is evidence that heparin in contrast with hirudin prevents AT from being bound to the endothelial cell surface in this experimental model. Under low-dose AT substitution, systemic prostacyclin concentrations do not depend on whether heparin or hirudin is used for thrombin inhibition. These results support the view that heparin may counteract anti-inflammatory AT effects by keeping AT away from its endothelial binding sites; however, the results question the view that decreased endothelial prostacyclin release is solely responsible.

Animals↗
PubMed2000

[Contribution of Berlin clinics and especially the Charité to the development of modern anesthesia in Germany].

Soon after announcement of the first American ether anesthesias in 1846 one started to anesthetize with ether in Europe. The first ether anesthesia in Germany took place on January 24th, 1947, and was given by Johann Ferdinand Heyfelder in Erlangen. Two weeks later the first ether anesthesia in Berlin was given on February 6th, 1847, by the orthopaedic surgeon Heimann-Wolff Berend. On February 12th, 1847, the surgeon Johann Friedrich Dieffenbach used ether to anesthetize a patient in the Berlin university hospital. Still in 1847 he published his book "The Ether against Pain" which used to be the standard textbook of anesthesia in Germany for many years to come. On February 15th, 1847, Johann Christian Jüngken operated his first patient under ether anesthesia in the surgical department of the Charité hospital assisted by Rudolf Virchow. Since then several famous Berlin surgeons influenced the development of modern anesthesia until the middle of the 20th century. The nitrous oxide bottle was introduced into practice by the Barth company in cooperation with the dentist Carl Sauer and Kurt Schimmelbusch introduced his mask for ether anesthesia. Carl Ludwig Schleich reported at the German congress of surgery in 1894 about his first experience with infiltration anesthesia. Spinal anesthesia developed by August Bier in Kiel was improved during his time in Berlin.

Anesthesia↗