PubMed HealthSearch

Biomedical subjects

B Schneeweiss

Publications and source records attributed to B Schneeweiss.

At least 19 recordsLinked to original sources

Diagnosis of gallbladder perforation in acute acalculous cholecystitis in critically ill patients.

In the presence of ascites ultrasound is not appropriate to distinguish between gallbladder perforation and acute acalculous cholecystitis. However, the correct and early diagnosis of gallbladder perforation is important for the treatment and prognosis. We report 4 critically ill patients with ascites. All patients had evidence of gallbladder perforation by ultrasound and underwent cholecystectomy: 2 patients had gallbladder perforation, but 2 had acalculous cholecystitis without perforation. Markedly elevated serum alkaline phosphatase was the only discriminating finding indicating gallbladder perforation.

Adult

Short-term energy balance in patients with infections: carbohydrate-based versus fat-based diets.

The effects of a carbohydrate-based diet (50% carbohydrate calories, 30% fat calories, 20% protein calories) versus a fat-based diet (28% carbohydrate calories, 55% fat calories, 17% protein calories) on oxidation rates of carbohydrate, fat, and protein were assessed in 12 patients with infections by indirect calorimetry and estimation of urea nitrogen production rate. The diets were given continuously for 18 hours in a randomized cross-over study on 2 consecutive days. Energy supply (kcal/d) was adjusted individually to meet the energy expenditure measured on the preceding day after an overnight fast and was 1,647 +/- 129 (SEM) for the carbohydrate-based diet and 1,655 +/- 131 for the fat-based diet. Oxidation rates (kcal/d) for carbohydrate (carbohydrate-based diet, 525 +/- 70; fat-based diet, 363 +/- 84) were different between the diets (P less than .05), whereas no difference could be found for fat (carbohydrate-based diet, 820 +/- 117; fat-based diet, 968 +/- 136) and protein (carbohydrate-based diet, 252 +/- 29; fat-based diet, 236 +/- 23). However, during carbohydrate-based feeding, carbohydrate balance (288 +/- 93 kcal/d) and fat balance (-327 +/- 107 kcal/d) were significantly different from zero (P less than .05), indicating continuous oxidation of endogenous fat and storage of administered glucose. During the fat-based diet, carbohydrate and fat balances were not different from zero. A correlation between energy and substrate balances was not seen during either diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Fat elimination in acute renal failure: long-chain vs medium-chain triglycerides.

Elimination and hydrolysis of fat emulsions containing long-chain (LCT; Intralipid) or long- and medium-chain triglycerides (MCT; Lipofundin MCT) were compared in seven patients with acute renal failure (ARF) and six healthy control subjects. In control subjects, clearance of MCT was slightly higher than that of LCT (1.93 +/- 0.34 vs 1.55 +/- 0.3 mL.kg body wt-1.min-1, P less than 0.05). The rise in plasma triglycerides was similar and the release of free fatty acids was higher during MCT (P less than 0.02). In ARF, clearance of both LCT and MCT was equally reduced (0.53 +/- 0.12 vs 0.59 +/- 0.14 mL.kg body wt-1.min-1, P less than 0.01 vs control subjects). Again, the rise in triglycerides was comparable. Free fatty acid release was higher during MCT but lower than in control subjects. Plasma concentrations of glucose and lactate were not affected in control subjects but increased during both LCT and MCT in ARF. Thus elimination of both LCT and MCT is profoundly decreased in ARF. The impaired lipolysis in ARF cannot be circumvented by the use of MCT.

Acute Kidney Injury

Hyperlipidemia in acute hemolysis.

In 27 (78%) of 36 patients with massive hemolysis (defined as a fall in hematocrit of more than 12% within 12 h due to intravascular red cell destruction), hypertriglyceridemia (plasma triglycerides greater than 175 mg/dl) was present or appeared within two days after the hemolytic crisis. Eighteen subjects with triglycerides exceeding 300 mg/dl (peak 516 +/- 39 mg/dl) were further analyzed. The development of hyperlipidemia was independent of the etiology of hemolysis (microangiopathic hemolytic disease 7, toxicemia 3, parainfectious complications 3, autoimmune hemolysis 2, glucose-6-phosphate dehydrogenase deficiency 2). Factors known to increase plasma triglycerides, such as shock, infections, or pancreatitis, were present in only a few cases. Hemolysis-associated complications were activation of intravascular coagulation (16), coma (13), acute renal failure (13), and respiratory insufficiency (5), organ dysfunctions indicating diffuse microvascular injury. Plasma triglycerides fell within a few days if the cause of red cell destruction was eliminated. In 5 of the 8 patients presenting with triglycerides below 175 mg/dl, severe hepatic dysfunction was present. We conclude that hemolysis causes transient hyperlipidemia, either directly by red cell destruction or indirectly by inducing intravascular coagulation, and possibly due to both increased triglyceride synthesis and decreased catabolism.

Adolescent

Evoked potentials in severe herpes simplex encephalitis.

Diagnostic and prognostic value of evoked potentials (EP) were studied in 5 patients with severe herpes simplex encephalitis (HSE). Latency of the third negative cortical N70 peak, elicited by median nerve stimulation, was prolonged in 3 survivors with Glasgow coma score of less than or equal to 6 (115 vs 71 ms in controls, p less than 0.05), but normal after improvement of the acute disease. N70 right to left interhemisphere difference was increased initially in the 4 survivors (26 vs 3 ms in controls, p less than 0.05) indicating focal brain involvement, a crucial finding in HSE. The first cortical N20 peak was preserved in all survivors even during deep coma where evaluation of brain function is difficult. Auditory brainstem EP were normal in all patients and useful to exclude brainstem death. In severe HSE, somatosensory long-latency EP are an effective monitor of the level of impaired consciousness and can detect brain focal signs. Short-latency N20 components may be predictive of the outcome.

Adolescent

Pancreatitis in acute hemolysis.

Forty cases of hemolysis (drop of hematocrit greater than 12%/12 h) were retrospectively analyzed for hyperamylasemia and pancreatic complications. In 15 subjects the serum amylase level was greater than 360 U/l, i.e., three times the normal range, in ten the amylase level exceeded 900 U/l. Excluding patients in circulatory shock and/or hepatic coma, acute pancreatitis as defined by an elevation of serum amylase and clinical signs (epigastric pain) was present in four, with additional ultrasound findings (pancreatic swelling) and/or laparatomy/postmortem findings in a further six subjects (total ten patients = 25%) with various causes of hemolysis: autoimmune hemolysis 2, microangiopathic hemolytic anemia 2, toxicemia, G-6-PDH deficiency, septic abortion, malaria, Wilson's disease, and hypophosphatemia, one case each. In all subjects acute renal failure and in seven an activation of intravascular coagulation was seen. Three patients died (33% vs 47% of all hyperamylasemic patients and 46% of the whole group), but none of the deaths was attributed to pancreatitis. Pancreatic postmortem findings were diffuse edema and patchy parenchymal necrosis in two cases and petechial bleeding in one case. We conclude that acute pancreatitis is a complication of massive hemolysis, occurring at a prevalence of above 20%. It may progress from diffuse edema and inflammation to focal necrosis, rarely if ever to gross hemorrhage, and does not contribute to the high mortality of massive hemolysis. Back pain in hemolysis might originate from the pancreas rather than from the kidneys.

Adolescent

Ornipressin in the treatment of functional renal failure in decompensated liver cirrhosis. Effects on renal hemodynamics and atrial natriuretic factor.

In 11 patients with decompensated cirrhosis and deteriorating renal function, the effect of the vasoconstrictor substance 8-ornithin vasopressin (ornipressin; POR 8; Sandoz, Basel, Switzerland) on renal function, hemodynamic parameters, and humoral mediators was studied. Ornipressin was infused at a dose of 6 IU/h over a period of 4 hours. During ornipressin infusion an improvement of renal function was achieved as indicated by significant increases in inulin clearance (+65%), paraaminohippuric acid clearance (+49%), urine volume (+45%), sodium excretion (+259%), and fractional elimination of sodium (+130%). The hyperdynamic circulation was reversed to a nearly normal circulatory state. The increase in systemic vascular resistance (+60%) coincided with a decrease of a previously elevated renal vascular resistance (-27%) and increase in renal blood flow (+44%). The renal fraction of the cardiac output increased from 2.3% to 4.7% (P less than 0.05). A decline of the elevated plasma levels of noradrenaline (2.08-1.13 ng/mL; P less than 0.01) and renin activity (27.6-14.2 ng.mL-1.h-1; P less than 0.01) was achieved. The plasma concentration of the atrial natriuretic factor increased in most of the patients, but slightly decreased in 3 patients. The decrease of renal vascular resistance and the increase of renal blood flow and of the renal fraction of cardiac output play a key role in the beneficial effect of ornipressin on renal failure. These changes develop by an increase in mean arterial pressure, the reduction of the sympathetic activity, and probably of an extenuation of the splanchnic vasodilation. A significant contribution of atrial natriuretic factor is less likely. The present findings implicate that treatment with ornipressin represents an alternative approach to the management of functional renal failure in advanced liver cirrhosis.

Atrial Natriuretic Factor

Inhibition by etomoxir of carnitine palmitoyltransferase I reduces hepatic glucose production and plasma lipids in non-insulin-dependent diabetes mellitus.

To determine the therapeutic effect of the carinitine palmitoyltransferase I (CPT-I) inhibitor, etomoxir, eight hospitalized obese non-insulin-dependent diabetes mellitus (NIDDM) patients were studied (body mass index [BMI], 28.7 +/- 1.3 kg/m2; age, 54 +/- 8 years [means +/- SE]) at baseline (placebo = t1), and after oral etomoxir (50 mg/d = t2, 100 mg = 3, 150 mg = t4, 200 mg = t5, placebo = t6). Fasting blood glucose (mmol/L), triglycerides (mmol/L), cholesterol (mmol/L), free fatty acids (mumol/L), beta-hydroxybutyrate (mumol/L), and alanine aminotransferase (GPT, U/L) were determined (t1 to t6), as were glucose utilization (M value; indirect calorimetry) and hepatic glucose production during a 10 mU/kg.min euglycemic clamp (t1 and t4). A dose-dependent decrease was induced by etomoxir in fasting blood glucose (t1 to t5: 9.5 +/- 0.7, 8.7 +/- 1.0, 8.3 +/- 1.1 [P v t1 less than .05], 7.8 +/- 0.9, [P v t1 less than .01], 7.9 +/- 1.1 [P v t1 less than .05]), which was reversible in t6 (9.9 +/- 1.1). Mean plasma lipids were reduced (t1 v t5) for triglycerides (-54%, P v t1 less than .01), cholesterol (-24%, P v t1 less than .05), and beta-hydroxybutyrate (-44%, P v t2 less than .01), while free fatty acids increased by 52% (P v t1 less than .05), as did GPT (t1: 17 +/- 3; t5: 32 +/- 7 U/L [P v t1 less than .01]).(ABSTRACT TRUNCATED AT 250 WORDS)

3-Hydroxybutyric Acid

Lactic acid kinetics in respiratory alkalosis.

OBJECTIVE: To evaluate the impact of respiratory alkalosis on the elimination of intravenously infused lactate. DESIGN: Prospective, randomized, crossover study. SETTING: Medical ICU of a university hospital. PATIENTS: Eight patients treated by ventilatory support for neurologic or neuromuscular diseases. INTERVENTIONS: Patients were investigated on two occasions: during normoventilation (pH 7.42 +/- 0.1, PCO2 41 +/- 2 torr [5.5 +/- 0.2 kPa]) and during respiratory alkalosis (pH 7.59 +/- 0.1, PCO2 27 +/- 2 torr [3.6 +/- 0.2 kPa]) induced by controlled hyperventilation. To evaluate lactate elimination kinetics, 1 mmol/kg body weight of L-lactic acid was infused over 5 mins. MEASUREMENTS AND MAIN RESULTS: Arterial lactate concentrations and blood gas values were determined before and repeatedly after the infusion. Lactate elimination variables were calculated from the plasma curve by using a two-compartment model. Respiratory alkalosis increased plasma lactate from 1.56 +/- 0.1 to 2.49 +/- 0.2 mmol/L (p less than .001). The lactate elimination half-life increased from 4.57 +/- 0.2 mins at pH 7.42, to 9.96 +/- 1.1 mins during pH 7.59 (p less than .01), and beta half-life increased from 12.2 +/- 1.9 to 44.1 +/- 1 mins (p less than .01). Whole-body clearance decreased 40% from 24.2 +/- 2.9 to 14.3 +/- 2.0 mL/kg body weight-min (p less than .01). CONCLUSIONS: Respiratory alkalosis increases the basal concentration of plasma lactate and decreases clearance of infused lactic acid. These findings provide further evidence of the adverse effects of alkalosis.

Aged

[Successful bridge transplantation with the Vienna artificial heart].

The Vienna Heart, a pulsatile artificial ventricle, vacuum-formed from Pellethane has been used successfully as total artificial heart (TAH) and left ventricular assist device (LVAD) to bridge over patients in terminal heart failure. A 50 year-old patient with cardiomyopathy had to be resuscitated and was transferred in cardiogenic shock, with impaired renal and liver function. 6 days after orthotopic implantation of a Vienna TAH a suitable donor organ was found and the patient was transplanted. 7 weeks later he was discharged and is alive and well now. A 40-year-old patient was transferred in cardiogenic shock 22 days after recurrent anterior infarction. Due to renal failure he was on haemofiltration. Congestive liver failure caused a severe coagulation disorder so a Vienna LVAD was implanted without the use of extracorporeal circulation. Despite development of septicaemia he was transplanted 24 days later. It was thought that either the ventricular thrombus or the LVAD was the septic focus. All consecutive blood cultures have been negative and he was discharged 6 weeks later. To our knowledge, case 1 represents the first successful bridging with a non-Jarvic TAH. The second case shows that sepsis is not necessarily a contraindication to heart transplantation.

Adult

[Weaning using continuous-flow CPAP: hemodynamics and gas exchange].

The present study was designed to investigate hemodynamics and gas exchange during weaning from mechanical ventilation (assist/control mode) to spontaneous breathing with continuous high flow (chf)-CPAP, and to study the predictive value of these parameters in respect of longterm success or failure of weaning. Hemodynamic and gas exchange parameters were obtained in 10 patients without severe pulmonary and cerebral dysfunction at -240, -60, -30, and -15 min before, and at +15, +30, +45, +60, +120, +180, +240 min after chf-CPAP. During chf-CPAP significant increases in heart rate/min (92 +/- 17 to 103 +/- 20), cardiac index (3.9 +/- 0.7 to 4.4 +/- 1.0 1/min.m2), respiratory rate/min (15 +/- 1 to 28 +/- 7), PaCO2 (36.7 +/- 3.0 to 41.2 +/- 5.9 torr) and oxygen delivery (12.2 +/- 2.7 to 13.9 +/- 2.3 ml/min.kg) were found. Arterial and pulmonary artery pressures rose only briefly within the first hour. All other parameters changed non-significantly. In the 4 patients who required mechanical ventilation 12 to 34 hours after the end of the study we found a significantly more pronounced increase in heart rate than in those who where weaned successfully (114 +/- 19 vs 89 +/- 9). Increases in heart rate, respiratory rate, cardiac index, PaCO2 and oxygen delivery can therefore be expected during weaning from mechanical ventilation to spontaneous breathing with CPAP. A pronounced increase in heart rate may suggest a weaning failure.

Adult

Energy metabolism in patients with acute and chronic liver disease.

Energy expenditure and substrate oxidation rate for fat, glucose and protein were evaluated by indirect calorimetry in 20 normal individuals, 35 patients with acute hepatitis and 22 patients with biopsy-proven alcoholic cirrhosis in the postabsorptive state. Measurements were done in the resting state after an overnight fast (10 to 12 hr). Oxygen consumption (ml/min/1.73 m2) in normal subjects, in patients with acute hepatitis and in patients with cirrhosis was 206.5 +/- 4.0 (mean +/- S.E.M.), 216.4 +/- 4.7 and 228.8 +/- 7.1 (p less than 0.05 vs. controls), respectively. When related to body surface area (kcal/min/1.73 m2), resting energy expenditure did not differ between normal subjects (0.98 +/- 0.02), patients with acute hepatitis (1.03 +/- 0.02) and cirrhotic patients (1.06 +/- 0.03). However, when related to 24-hr urinary creatinine excretion as an estimate of lean body mass, energy expenditure was increased in cirrhosis (p less than 0.0001). In cirrhosis an inverse association between the severity of liver disease according to Pugh and oxygen consumption and resting energy expenditure was found. In cirrhotic patients the percentages of total calories derived from fat (86% +/- 5%), carbohydrate (2% +/- 4%) and protein (12% +/- 1%) were different from those of normal controls who metabolized 45% +/- 4%, 38% +/- 4%, 17% +/- 1%, respectively. In acute hepatitis no alterations in metabolism could be found apart from a decreased protein oxidation rate. In conclusion no appreciable changes in energy metabolism exist in acute hepatitis. The pattern of fuel use in cirrhosis resembles that in starvation.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease

Improvement of brain function in hemodialysis patients treated with erythropoietin.

To evaluate the effects of recombinant human erythropoietin (rHuEPO) on brain function, 15 chronic hemodialysis patients were studied by event-related P300, stimulus-related evoked potentials, and trailmaking before (hematocrit 22.7%) and after rHuEPO (hematocrit 30.6%). P300 peak latency elicited by a tone discrimination paradigm improved (391 before vs. 366 ms after; Cz = vertex; P less than 0.01) confirming beneficial effects on cerebral cognitive processing. P300 amplitude (13.6 vs. 15.8 microV; P = 0.06) and trailmaking tended to improve (55 vs. 43 s). P300 measures were influenced by low hemoglobin levels before rHuEPO (P less than 0.01), suggesting that severe anemia may contribute to uremic brain dysfunction. Furthermore, decrease of stimulus-related auditory brainstem I-V interpeak latency (4.28 before vs. 4.17 ms after; P less than 0.05) and increase of somatosensory N20/P25 amplitude (4.8 vs. 7.0 microV; P less than 0.05) pointed to improvement of sensory pathways by mechanisms unrelated to cognition. Brain dysfunction in chronic hemodialysis patients may, beside other factors, in part be caused by severe anemia and can be improved by rHuEPO treatment.

Anemia

Energy metabolism in acute and chronic renal failure.

Energy metabolism was measured by indirect calorimetry in 86 patients with various forms of renal failure and in 24 control subjects. In patients with acute renal failure with sepsis, oxygen consumption, carbon dioxide production, and resting energy expenditure were increased (P less than 0.05). In other groups with renal failure (acute renal failure without sepsis, chronic renal failure with conservative treatment or hemodialysis, and severe untreated azotemia) these indices were not different from those of control subjects. Urea nitrogen appearance was decreased in patients with chronic renal failure undergoing conservative treatment, in those with severe untreated azotemia, and in hemodialysis patients (P less than 0.05). We conclude that renal failure has no influence on energy expenditure as long as septicemia is absent. Reduced urea nitrogen appearance rates in chronic renal failure are due to a reduced energy and protein intake. Wasting is a consequence of decreased food intake but not of hypermetabolism in chronic renal failure.

Acute Kidney Injury

Electrophysiologic testing after aortic valve replacement in two patients with aortic stenosis and preoperative ventricular fibrillation.

In two patients with severe aortic stenosis successful resuscitation from ventricular fibrillation was documented by Holter recording/ECG monitoring. After aortic valve replacement programmed ventricular stimulation was performed in both patients, but ventricular tachycardia/ventricular fibrillation was not inducible. The patients were left without antiarrhythmic therapy and have been free from cardiac events for 18 and 20 months, respectively. The prognostic value of postoperative electrophysiologic testing after aortic valve replacement in patients with severe aortic stenosis and preoperative resuscitation is discussed.

Aortic Valve Stenosis