K A Brensing

University of Bonn, Bonn, North Rhine-Westphalia, Germany

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Publications (60)302 Total impact

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    ABSTRACT: Hepatorenal syndrome (HRS) is a frequent complication of end-stage liver cirrhosis. HRS type I has a very poor prognosis. From which of the more or less established therapies, such as use of vasoconstrictors together with albumin or placement of a Transjugular Intrahepatic Portosystemic Shunt patients might profit remains elusive. Therefore, it is important to define parameters that predict an improved outcome in respect to kidney function and survival. The clinical charts of 91 patients with cirrhosis and HRS type I were studied. The parameters associated with response to therapy, defined as a decrease in serum creatinine of more than 1.5 mg/dl on day 14 after diagnosis of HRS, and those associated with survival were assessed by multivariate analysis. The median survival was 2.7 (1.5-3.8) months. Three independent predictive factors for survival were identified: Child-Pugh score (P = 0.05), Model of End-Stage Liver Disease (MELD) score less than 20 (P = 0.01), and response to therapy (P = 0.02). The Child-Pugh score (P = 0.00) and MELD score less than 20 (P = 0.02) were the parameters independently associated with the response to therapy, which occurred in 26% of the patients. Our data of this large monocentric series with HRS type I confirm the poor prognosis in these patients, especially in those with high Child-Pugh and MELD scores, and in those in whom kidney function does not improve within 2 weeks.
    European journal of gastroenterology & hepatology 09/2009; 21(12):1428-32. · 1.66 Impact Factor
  • Nephrology Dialysis Transplantation 02/2008; 23(1):385-6. · 3.37 Impact Factor
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    ABSTRACT: Recently, new prognostic models (Model for End-Stage Liver Disease [MELD model] and Emory score) were proposed for the prediction of survival in transjugular intrahepatic portosystemic shunt (TIPS) patients. Although the MELD model is considered to be superior and has consecutively been applied to priority listing for liver transplantation, these models have never been directly compared in terms of long-term prognosis. We therefore compared the prognostic accuracy of the different models, including the Child-Pugh score, in an unselected cohort of TIPS patients followed long-term. Baseline risk scores for 162 unselected consecutive TIPS patients followed until death (n = 81), liver transplantation, or end of observation (n = 81) (mean follow-up 30.7 +/- 26.4 months) were calculated, and respective concordance- (c-)statistics for the predictive accuracy of 3-, 12-, and 36-month survival for the three models were compared statistically. All three models predicted short-term (3-month) survival with similar accuracy. The MELD model generated the best c-statistics for both 12-month (c-statistic 0.73, 95% CI = 0.64-0.82) and 36-month survival (c-statistic 0.74, 95% CI = 0.64-0.84). The predictive accuracy of the Emory score was significantly lower (c-statistic for 12-month survival: 0.60, 95% CI = 0.52-0.68, p = 0.012 vs MELD). In the statistical comparison of the MELD and the Child-Pugh model, only a trend favoring MELD for the prediction of 1-yr survival in patients with intestinal bleeding could be observed (MELD: c-statistic 0.78, 95% CI = 0.67-0.89; Child-Pugh: c-statistic 0.67, 95% CI = 0.55-0.80, p = 0.059). The MELD model is superior to the Emory score but only slightly superior to the Child-Pugh classification for the prediction of long-term survival in TIPS patients.
    The American Journal of Gastroenterology 06/2003; 98(5):1167-74. · 7.55 Impact Factor
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    ABSTRACT: Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) in healthy humans can be induced by amino acid stimulation. The rise in GFR from baseline to maximum is referred to as the renal functional reserve (RFR). Recently, we showed that the RFR is preserved in patients with compensated cirrhosis despite impaired renal function. In the present study, we evaluated RFR in decompensated cirrhotics with ascites. Steady-state inulin- and para-aminohippurate (PAH) clearances were performed at rest and during amino acid infusion in 22 patients with decompensated liver cirrhosis and ascites. Baseline GFR and ERPF (means +95% confidence intervals) were: GFR 25.2 (21.1-29.2) ml min(-1), ERPF 266.6 (229.7-303.5). Amino acid infusion significantly increased GFR by 67% (38.3-95.8) to 34.6 (29.2-40.0) ml min(-1) (means + (95% confidence intervals), P < 0.001) and ERPF by 29% (11.9-46.3) to 326.3 (274.1-378.5) ml min(-1) (P = 0.002). Renal vascular resistance dropped by 13.4% (3.3-23.5) from 29.4 (24.8-33.9) mmHg ml(-1) min(-1) to 26.4 (22.0-30.7) mmHg ml(-1) min(-1) (P = 0.036). The improved kidney function was accompanied by a decrease in systemic aldosterone levels (P < 0.05). In patients with liver cirrhosis and ascites, amino acid infusion improves kidney function. Trials are warranted to test the long-term effects of amino acid infusions in patients with hepatorenal syndrome.
    Scandinavian Journal of Gastroenterology 12/2002; 37(11):1321-7. · 2.33 Impact Factor
  • Karl August Brensing, Peter Raab, Ulrich Frotscher
    New England Journal of Medicine 10/2002; 347(12):947-8; author reply 947-8. · 51.66 Impact Factor
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    ABSTRACT: The combination of tailored TIPS with vasoactive drugs might allow reduction of the rate of subsequent shunt-related sequelae. We studied cirrhotic patients 8 weeks (median) after TIPS insertion (8-10 mm) for variceal bleeding. Nitrate (0.1 mg/kg) and propranolol (0.15 mg/kg) alone or combined (same dosages) were infused (I h) sequentially at 1-h intervals (n = 17). Similarly, propranolol was randomly compared to placebo (NaCl, n = 14). We measured mean arterial pressure (MAP, mmHg), heart rate (HR) and portal pressure gradient (PPG: portal minus central venous pressure) prior to and after drugs. Propranolol reduced PPG (mean +/- s, mmHg) significantly (14.8 +/- 3.7 versus 12.1 +/- 3.7; -21% +/- 10%; P < 0.001), while nitrates alone (14.3 +/- 3.4 versus 13.7 +/- 3.4; -11% +/- 3%; P=0.06) or nitrates plus propranolol (12.9 +/- 4 versus 12.4 +/- 4; -7% +/- 8%; P=0.2) induced only minor additive effects on portal pressure. However, nitrate reduced MAP (P < 0.001) and increased HR (P < 0.01), whereas propranolol reduced only HR (P < 0.001) with unchanged MAP, and the combination decreased MAP (P < 0.001). Compared to placebo (no effect), propranolol decreased PPG (14.4 +/- 5.6 versus 11.1 +/- 5.5; -23% +/- 11%; P < 0.001) and HR (P < 0.001). Overall, most patients (92%) responded to propranolol and 54% showed a marked PPG decrease (>20%). Propranolol significantly reduced portal pressure in cirrhotic patients after TIPS, whereas nitrates induced only minor benefit. TIPS-treated patients might therefore profit from additive propranolol therapy allowing limited shunts to be applied initially and/or to reduce the need for TIPS revisions in the case of shunt-dysfunction during follow-up.
    Scandinavian Journal of Gastroenterology 09/2002; 37(9):1070-6. · 2.33 Impact Factor
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    ABSTRACT: Transjugular intrahepatic portosystemic stent-shunt (TIPSS) is increasingly used to treat complications of portal hypertension, but proven tools for risk assessment of early mortality are lacking. The prospective evaluation of a new 60-day mortality score. In a tertiary medical centre, 30 consecutive TIPSS patients were analysed for early mortality predictors, such as Child-Pugh score, TIPSS urgency (elective: > or = 36 h or emergency: < 36 h after variceal bleeding), comorbidity (Acute Physiology and Chronic Health Evaluation [APACHE]-II) and clinical data. Main predictors (P< 0.01) in this group (group-1: Child-Pugh score 10A, 10B, 10C) were graded (1, 2 or 3 points representing low, medium and high risk, respectively) and summarized as a Bonn TIPSS early mortality (BOTEM) score. This score was then tested prospectively in the next 73 TIPSS patients (group-2: Child-Pugh score 14A, 42B, 17C). Group 1 early mortality (30%) depended primarily on bilirubin (P< 0.005), APACHE-II (P < 0.001) and TIPSS urgency (P< 0.001). Added risk points (1, 2, 3) for bilirubin (< 3 mg/dl, 3-6 mg/dl, > 6 mg/dl, respectively), APACHE-II (< 10, 10-20, > 20 points, respectively) and urgency (elective, emergency, active bleeding, respectively) represented individual BOTEM score points. BOTEM was the best mortality predictor (P< 0.001); < or = / > 6 score points was the optimal cut-off, with 56% sensitivity, 100% specificity, 100% positive predictive value, 84% negative predictive value and 87% accuracy. In group 2, early mortality (8.2%) was again best predicted by BOTEM (P < 0.01) with the same cut-off and 67% sensitivity, 99% specificity, 80% positive predictive value, 97% negative predictive value and 96% accuracy. BOTEM score based on bilirubin, comorbidity and TIPSS-urgency predicts rather reliably post-TIPSS 60-day mortality and might optimize TIPSS treatment.
    European Journal of Gastroenterology & Hepatology 07/2002; 14(7):723-31. · 1.92 Impact Factor
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    ABSTRACT: The aim of the present study was to compare the transjugular intrahepatic portosystemic shunt (TIPS) with variceal band ligation (VBL) in the prophylaxis of variceal rebleeding in patients with cirrhosis of the liver. Fifty-four cirrhotic patients (21 Child-Pugh class A, 27 class B, 6 class C) were randomized to TIPS (n = 28) or VBL (n = 26) within 2 months after control of esophageal variceal hemorrhage. Statistical analysis was performed on the intention-to-treat principle. Mean follow-up was 2 years. Mortality risk at 1 and 2 years of follow-up was 7.8% +/- 5.3% and 19.9% +/- 8.8% in the TIPS group and 16.5% +/- 7.6% and 16.5% +/- 7.6% in the VBL group, respectively (n.s.); actuarial probability of remaining free from rebleeding was 83.7% +/- 77.4% and 71.4% +/- 10.4% in the TIPS group and 83.9% +/- 7.3% and 78.1% +/- 8.8% in the VBL group at 1 and 2 years, respectively (n.s.). Hepatic encephalopathy within 1 month after randomization was observed in 2 patients in the TIPS group and in 1 in the VBL group. TIPS is not superior to VBL in the prevention of variceal rebleeding. Furthermore, similar mortality rates in patients treated with TIPS or VBL negate TIPS as the preferred strategy for prevention of variceal rebleeding.
    Scandinavian Journal of Gastroenterology 04/2002; 37(3):338-43. · 2.33 Impact Factor
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    ABSTRACT: Increased concentrations of homocysteine probably contribute to the high cardiovascular morbidity and mortality in hemodialysed end-stage renal disease (ESRD) patients and are determined by a variety of factors such as age, residual renal function, and vitamin status. Fasting plasma concentrations of total homocysteine, methionine, cysteine, and cystathionine were determined by gas chromatography-mass spectrometry (GC-MS) in 131 ESRD patients receiving daily oral folate (160-320 microg) and vitamin B6 (10-20 mg) supplements. Concentrations of homocysteine determined by GC-MS were compared with those measured by high-performance liquid chromatography (HPLC) and an immunofluorescence method (IMx analyzer) using Passing-Bablok regression analysis. Mean plasma concentration of total homocysteine determined by GC-MS (28.7+/-11.9 micromol/l [mean+/-SD]) was significantly lower than that determined by HPLC (34.0+/-14.5 micromol/l; p<0.001) or IMx (32.4+/-13.9 micromol/l; p<0.001). A close correlation existed between GC-MS and HPLC (r=0.931; y=1.203 x+0.279) and GC-MS and IMx (r=0.896; y=1.105 x+0.766). Linear regression analysis showed positive correlations between plasma concentrations of homocysteine and cysteine (r=0.434; p<0.001) and homocysteine and cystathionine (r=0.187; p=0.032). Plasma concentrations of homocysteine correlated negatively with folate (r=-0.281; p=0.001) and vitamin B12 (r=-0.229; p=0.009). GC-MS proved to be a sensitive and reliable method for the determination of total plasma homocysteine and related amino acids. Despite vitamin supplementation, ESRD patients requiring chronic maintenance hemodialysis, have high plasma concentrations of homocyst(e)ine which seems to be metabolized mainly within the transsulfuration pathway, while remethylation to methionine seems to be disturbed.
    Clinical Chemistry and Laboratory Medicine 08/2001; 39(8):681-90. · 3.01 Impact Factor
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    ABSTRACT: To detect any harmful effects of prone positioning on intraabdominal pressure (IAP) and cardiovascular and renal function, we studied 16 mechanically ventilated patients with acute lung injury randomly in prone and supine positions, without minimizing the restriction of the abdomen. Effective renal blood flow index and glomerular filtration rate index were determined by the paraaminohippurate and inulin clearance techniques. Prone positioning resulted in an increase in IAP from 12 +/- 4 to 14 +/- 5 mm Hg (P < 0.05), PaO(2)/fraction of inspired oxygen from 220 +/- 91 to 267 +/- 82 mm Hg (P < 0.05), cardiac index from 4.1 +/- 1.1 to 4.4 +/- 0.7 L/min (P < 0.05), mean arterial pressure from 77 +/- 10 to 82 +/- 11 mm Hg (P < 0.01), and oxygen delivery index from 600 +/- 156 to 648 +/- 95 mL. min(-)(1). m(-)(2) (P < 0.05). Renal fraction of cardiac output decreased from 19.1% +/- 12.5% to 15.5% +/- 8.8% (P < 0.05), and renal vascular resistance index increased from 11762 +/- 6554 dynes. s. cm(-)(5). m(2) to 15078 +/- 10594 dynes. s. cm(-)(5). m(2) (P < 0.05), whereas effective renal blood flow index, glomerular filtration rate index, filtration fraction, urine volume, fractional sodium excretion, and osmolar and free water clearances remained constant during prone positioning. Prone positioning, when used in patients with acute lung injury, although it is associated with a small increase in IAP, contributes to improved arterial oxygenation and systemic blood flow without affecting renal perfusion and function. Apparently, special support to allow free chest and abdominal movement seems unnecessary when mechanically ventilated, hemodynamically stable patients without abdominal hypertension are proned to improve gas exchange. IMPLICATIONS: Prone positioning is increasingly used to improve gas exchange in patients with acute lung injury. However, during prone positioning an increase in intraabdominal pressure in these critically ill patients may promote dysfunction of other organs. Therefore, we performed a randomized study in mechanically ventilated patients with acute lung injury to investigate the cardiovascular and renal effects of prone positioning.
    Anesthesia & Analgesia 05/2001; 92(5):1226-31. · 3.30 Impact Factor
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    ABSTRACT: The aim of this prospective study was to compare noninvasive Doppler sonography and invasive measurement of the hepatic venous pressure gradient (HVPG) to determine the acute portal hemodynamic response to propranolol in patients with liver cirrhosis. In a blinded study design, portal vein velocity (PVV) and HVPG were simultaneously assessed in 11 cirrhotic patients for 4 h after oral ingestion of 40 mg propranolol. Both HVPG (17.2% +/- 4.3%, p < 0.0001) and PVV (15.6% +/- 2.1%, p < 0.0002) showed a highly significant reduction during the study period versus baseline. Based on HVPG measurements, four patients (36%) were classified as nonresponders. These patients had a significantly lower PVV reduction compared to the responders (responders: 18.8% +/- 2.0% vs nonresponders: 10.0% +/- 2.1%, p < 0.05). Nonresponders were identified by Doppler sonography with a sensitivity of 1.0, specificity of 0.86, and positive predictive value of 0.9 when a threshold of 20% PVV reduction 120 min after drug intake was applied. Doppler sonography is a useful tool for assessment of the acute portal hemodynamic effect of propranolol. To distinguish portal hemodynamic nonresponders from responders to propranolol, PVV measurements should be carried out 2 h after drug administration, and PVV reduction should be not <20% in propranolol responders.
    The American Journal of Gastroenterology 11/2000; 95(10):2905-9. · 7.55 Impact Factor
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    ABSTRACT: It has been suggested that the major metabolic block in the methionine catabolic pathway in cirrhotics exists at the level of the enzyme S-adenosylmethionine synthetase because in previous studies using conventional amino-acid analyzers, no intermediates of transmethylation/transsulfuration were found to accumulate in plasma downstream of S-adenosylmethionine synthesis. We therefore measured serum concentration intermediates of methionine transmethylation/transsulfuration using an improved gas chromatography/mass spectrometry technique. Serum concentrations of methionine, homocysteine, cystathionine, N,N-dimethylglycine, N-methylglycine, methylmalonic acid, 2-methylcitric acid and alpha-aminobutyric acid were determined by gas chromatography/mass spectrometry in 108 consecutive patients with liver cirrhosis at Child stages A (mild cirrhosis, n = 27) and B/C (severe cirrhosis, n = 81), 18 outpatients with non-cirrhotic liver disease, and 55 healthy individuals. Serum levels of methionine, N,N-dimethylglycine, N-methylglycine, cystathionine, and homocysteine were significantly higher in patients at Child stages B/C compared with those of healthy controls (P < 0.01), and they were also significantly higher than in patients with non-cirrhotic liver disease (P < 0.01 and P < 0.05 for homocysteine, respectively). They also correlated with the Child-Pugh score (P < 0.01). Homocysteine, cystathionine, N,N-dimethylglycine, N-methylglycine, methylmalonic acid, and 2-methylcitric acid correlated with serum creatinine. The mean cystathionine concentration was significantly higher in patients with creatinine > or = 1.4 mg/dl than in patients with normal creatinine values (P < 0.01). However, the differences between cirrhotics and healthy controls were still significant after correcting for creatinine. Our data provides indirect evidence for two hitherto unrecognized alterations of methionine metabolism in cirrhotics, i.e. impairment of the transsulfuration of homocysteine at the level of cystathionine degradation and a shift in remethylation of homocysteine towards the betaine-homocysteine-methyltransferase reaction.
    Scandinavian Journal of Gastroenterology 08/2000; 35(8):866-72. · 2.33 Impact Factor
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    ABSTRACT: Recent small studies on hepatorenal syndrome (HRS) indicate some clinical benefit after transjugular intrahepatic portosystemic stent-shunt (TIPS) but sufficient long term data are lacking. We studied prospectively feasibility, safety, and long term survival after TIPS in 41 non-transplantable cirrhotics with HRS (phase II study). HRS was diagnosed using current criteria (severe (type I) HRS, n=21; moderate (type II) HRS, n=20). Thirty one patients (14 type I, 17 type II) received TIPS (8-10 mm) while advanced liver failure excluded shunting in 10. During follow up (median 24 months) we analysed renal function and survival (Kaplan-Meier). TIPS markedly reduced the portal pressure gradient (21 (5) to 13 (4) mm Hg (mean (SD)); p<0.001) with one procedure related death (3.2%). Renal function deteriorated without TIPS but improved (p<0.001) within two weeks after TIPS (creatinine clearance 18 (15) to 48 (42) ml/min; sodium excretion 9 (16) to 77 (78) mmol/24 hours) and stabilised thereafter. Following TIPS, three, six, 12, and 18 month survival rates were 81%, 71%, 48%, and 35%, respectively. As only 10% of non-shunted patients survived three months, total survival rates were 63%, 56%, 39%, and 29%, respectively. Multivariate Cox regression analysis revealed bilirubin (p<0.001) and HRS type (p<0.05) as independent survival predictors after TIPS. TIPS provides long term renal function and probably survival benefits in the majority of non-transplantable cirrhotics with HRS. These data warrant controlled trials evaluating TIPS in the management of HRS.
    Gut 08/2000; 47(2):288-95. · 10.73 Impact Factor
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    ABSTRACT: This investigation was performed to compare the hemodynamic results of the transjugular intrahepatic portosystemic shunt, a new interventional treatment for portal hypertension, with those observed after the established surgical shunt interventions. We examined 22 patients with portal hypertension due to liver cirrhosis before and after elective TIPS by liver perfusion scintigraphy. The relative portal perfusion was determined before and after the shunt procedure. Additionally, we measured the portal pressure gradient (PPG: portal-central venous pressure, mmHg). Prior to TIPS, the relative portal perfusion was significantly reduced to 22 +/- 9.1%. After the intervention we calculated values of 23.1 +/- 10.7% in the TIPS-group (p = 0.67; not significant). In spite of unchanged portal perfusion, the portal pressure was significantly (p < 0.001) reduced from 25.6 +/- 5.3 to 14.8 +/- 4 mm Hg. These results suggest that the reduction of portal hypertension by TIPS is effective. The portal perfusion is maintained by TIPS suggesting that liver perfusion is preserved to a higher degree.
    Nuklearmedizin 08/2000; 39(5):139-41. · 1.67 Impact Factor
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    ABSTRACT: Recently, the beneficial effects of ursodeoxycholic acid (UDCA) on the portal hypertensive state have been demonstrated in patients with primary biliary cirrhosis. However, it is not known whether UDCA has direct or indirect effects on the vascular smooth muscles in humans, thereby leading to a change in splanchnic or systemic hemodynamics. We therefore evaluated the hemodynamic effects of UDCA as to its established effect on gallbladder motility under fasting and postprandial conditions in healthy volunteers. In a double-blind, cross-over study of 20 healthy volunteers, placebo or UDCA (750 mg/d) were randomly administered over 4 weeks with an interim 4-week washout period. Portal blood flow, cardiac output and gallbladder motility were measured using echo-Doppler and b-mode sonography before and after placebo and verum, respectively. ECG, blood pressure, heart rate and blood chemistry were also measured. UDCA did not significantly change fasting portal flow or meal-induced portal hyperemia. Both fasting and postprandial gallbladder volumes increased (26.5 +/- 6.0 vs. 40.7 +/- 13.8 ml, p < 0.05, and 11.2 +/- 6.2 vs. 14.8 +/- 6.7 ml, p < 0.05). Diastolic blood pressure decreased under UDCA (71.2 +/- 8.7 vs. 66.5 +/- 6.5 mm Hg, p < 0.05). Serum levels of chloride and gamma-glutamyltransferase decreased slightly, while alkaline phosphatase increased. UDCA affected systemic but not portal hemodynamics. The increase in gallbladder volume is obviously mediated by factors that do not influence the splanchnic vascular bed.
    Digestion 02/2000; 61(2):107-12. · 1.94 Impact Factor
  • Atherosclerosis 01/2000; 151(1):253-253. · 3.71 Impact Factor
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    ABSTRACT: The haemodynamic effect of propranolol on portal pressure in patients with portal hypertension is highly variable and does not correlate with propranolol racemate plasma concentrations. To investigate the stereoselective metabolism of the propranolol enantiomers and its impact on portal haemodynamics in patients with liver cirrhosis since only S-propranolol is haemodynamically active. Twenty patients with liver cirrhosis and portal hypertension received 40 mg propranolol orally. Portal blood velocity (PBV) and propranolol stereoisomer plasma concentrations were determined. During the 4 h examination period we observed a significant reduction in PBV (18.3 +/- 2.2%, P < 0.0001) vs. baseline. The area under the curve (AUC) during the study period was significantly different for the two isomers (S-propranolol 1217.0 +/- 118.5 nmol.h/L; R-propranolol 728.8 +/- 103.8 nmol.h/L, P < 0.0001). Seven patients (35%) were portal haemodynamic non-responders to propranolol. Propranolol stereoisomer AUC values were no different between responders (S-propranolol 1133. 3 +/- 132.0 nmol.h/L; R-propranolol 718.0 +/- 129.7 nmol.h/L) and non-responders (S-propranolol 1371.8 +/- 250.5 nmol.h/L; R-propranolol 746.9 +/- 200.3 nmol.h/L); neither was there a correlation between propranolol enantiomer plasma concentrations and the portal haemodynamic effect. Our data demonstrate a stereoselective metabolism of propranolol enantiomers in liver cirrhosis. However, following oral propranolol administration, stereoisomer plasma concentrations do not predict the portal haemodynamic effect.
    Alimentary Pharmacology & Therapeutics 11/1999; 13(11):1451-8. · 4.55 Impact Factor
  • DMW - Deutsche Medizinische Wochenschrift 10/1999; 124(36):1039-42. · 0.65 Impact Factor
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    ABSTRACT: Increased serum nitrite/nitrate (NOx) levels, the stable metabolites of nitric oxide (NO), have been reported in patients with cirrhosis. NOx levels, however, are influenced not only by endogenous NO synthesis but also by urinary NOx excretion and dietary intake. We attempted to elucidate factors that influence NOx levels independently of endogenous NO production and to determine the conditions under which NOx levels reflect endogenous production in patients with cirrhosis and healthy controls. NOx serum concentrations and urinary NOx excretion were determined by means of the Griess reaction in relation to Child-Pugh score, kidney function, fasting state, and after exposure to tap water. Multifactor regression analysis showed inulin clearance (P = 0.0074) and Child-Pugh score (P = 0.0001) to be independent factors predicting NOx levels in patients with cirrhosis. NOx serum levels correlated negatively with the inulin clearance (P < 0.0001), which deteriorated with progressive loss of liver function. NOx levels decreased by about 30% within a 24-h fasting period. After 24 h fasting urinary NOx excretion was not significantly increased in patients with advanced cirrhosis. NOx serum levels, taken as a surrogate for endogenous NO formation, have to be viewed with caution in patients with cirrhosis because they often have impaired kidney function. However, in steady-state conditions after an adequate fasting period NOx levels might be good prognostic markers in patients with cirrhosis since they reflect two possible sequelae of liver insufficiency-namely, increased NO formation and impaired kidney function.
    Scandinavian Journal of Gastroenterology 03/1999; 34(3):297-302. · 2.33 Impact Factor
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    ABSTRACT: This study evaluated the dependence of portal and mesenteric blood flow and plasma glucagon levels on octreotide dosage and its mode of application. Two groups of 10 individuals each received octreotide either subcutaneously (placebo, 100 and 200 microgram) or intravenously (100- microgram bolus i.v., 25 and 100 microgram/h) in a double-blind, random order. Using Doppler ultrasound, we examined portal and mesenteric blood flow and measured plasma glucagon levels at regular intervals within a 4-hour period under fasting conditions. Contrary to placebo, octreotide caused a decrease in portal blood flow (PVF) and in superior mesenteric artery blood flow (SMAF) together with an increase in the mesenteric pulsatility index (PI). The same total dose of 100 microgram octreotide caused a similar PVF response, averaged over 4 h, given either subcutaneously (-28.0 +/- 4.8%), intravenously (-29.4 +/- 4.3%) or as a continuous infusion (-29.3 +/- 4.6%). As concerns intravenous infusions, 100 microgram/h was more effective than 25 microgram/h (-37.8 +/- 6.2 vs. -29.3 +/- 4.6%). The PVF reduction remained constant during intravenous infusion, whereas glucagon levels decreased progressively over the entire observation time. The decrease in PVF is dependent on the octreotide dose. However, this is not constantly paralleled by a decrease in plasma glucagon concentration.
    Digestion 01/1999; 60(2):132-40. · 1.94 Impact Factor