Comparison Evaluation of Automated Nucleated Red Blood Cell Enumeration by Sysmex XN 1000 in Comparison With Microscopic Reference in Children Under 1 Year

BACKGROUND

In newborns, elevated nucleated red blood cell (NRBC) levels can be associated with enhanced erythropoietic stress and might be predictive for adverse outcome. Also, the presence of NRBC in peripheral blood might lead to erroneous enumeration results of white blood cells in automated hematology analyzers. We aimed to assess the comparability of the Sysmex XN 1000 to manual slide reviews and correlation of NRBC with inflammation markers.

METHODS

Specimens of 3397 children under 1 year were compared by automated and microscopic NRBC enumeration. Additionally, potential correlations between NRBC and age and inflammation markers were examined.

RESULTS

Overall, there was good correlation (r = 0.97) between automated (range: 0%-3883%) and microscopic enumeration (range: 0%-3694%) of NRBC with high comparability up to a NRBC value of 200% and an increase in the variation between the two methods with increasing NRBC numbers. When 94 samples with ≤ 200% NRBC and ≥ 30% divergence between methods were separately reanalyzed with respect to overlapping cell populations in their scattergrams, Sysmex would have generated unrecognized incorrect automated results in 47 samples, corresponding to 1.4% of total study samples. NRBC counts were negatively correlated to age, but not to inflammation markers.

CONCLUSION

Sysmex XN 1000 is highly precise in the enumeration of NRBC in children under 1 year up to counts of 200% and might replace time-intense manual counting in routine diagnostics. In the setting of neonatal and intensive care diagnostics, microscopic control and supervision of scattergrams are highly recommended for any automated NRBC enumeration processes.

Amniotic Epithelial Stem Cells Counteract Acidic Degradation By-Products of Electrospun PLGA Scaffold by Improving Their Immunomodulatory Profile In Vitro

Electrospun poly(lactic-co-glycolic acid) (PLGA) scaffolds with highly aligned fibers (ha-PLGA) represent promising materials in the field of tendon tissue engineering (TE) due to their characteristics in mimicking fibrous extracellular matrix (ECM) of tendon native tissue. Among these properties, scaffold biodegradability must be controlled allowing its replacement by a neo-formed native tendon tissue in a controlled manner. In this study, ha-PLGA were subjected to hydrolytic degradation up to 20 weeks, under di-H₂O and PBS conditions according to ISO 10993-13:2010. These were then characterized for their physical, morphological, and mechanical features. In vitro cytotoxicity tests were conducted on ovine amniotic epithelial stem cells (oAECs), up to 7 days, to assess the effect of non-buffered and buffered PLGA by-products at different concentrations on cell viability and their stimuli on oAECs’ immunomodulatory properties. The ha-PLGA scaffolds degraded slowly as evidenced by a slight decrease in mass loss (14%) and average molecular weight (35%), with estimated degradation half-time of about 40 weeks under di-H₂O. The ultrastructure morphology of the scaffolds showed no significant fiber degradation even after 20 weeks, but alteration of fiber alignment was already evident at week 1. Moreover, mechanical properties decreased throughout the degradation times under wet as well as dry PBS conditions. The influence of acid degradation media on oAECs was dose-dependent, with a considerable effect at 7 days’ culture point. This effect was notably reduced by using buffered media. To a certain level, cells were able to compensate the generated inflammation-like microenvironment by upregulating IL-10 gene expression and favoring an anti-inflammatory rather than pro-inflammatory response. These in vitro results are essential to better understand the degradation behavior of ha-PLGA in vivo and the effect of their degradation by-products on affecting cell performance. Indeed, buffering the degradation milieu could represent a promising strategy to balance scaffold degradation. These findings give good hope with reference to the in vivo condition characterized by physiological buffering systems.

B-type natriuretic peptide increases cortisol and catecholamine concentrations in healthy subjects

B-type natriuretic peptide (BNP) is a hormone released by the heart in response to volume load and exerts natriuretic properties. It is clinically used as a diagnostic and prognostic biomarker and investigated as a pharmacological agent in the therapy of heart failure. Here we investigate the changes in pituitary, adrenal, and thyroid hormones in response to BNP administration in a randomized single-blinded crossover study conducted in ten healthy men aged 21–29 yr. Participants received in two study sessions a continuous intravenous infusion during 4 h (once placebo and once 3 pmol·kg−1·min−1 BNP) and remained in supine position throughout the study. Circulating concentrations of pituitary, adrenal, and thyroid hormones, heart rate, and blood pressure were measured at baseline and hourly afterwards. BNP prevented the physiological decrease in cortisol during the late morning hours leading to elevated serum cortisol levels ( P = 0.022) and increased circulating epinephrine and norepinephrine concentrations ( P = 0.018 and P = 0.036, respectively). These hormone changes were accompanied by an increase in heart rate ( P = 0.019) but no differences in blood pressure. Taken together, the impact of BNP on the endocrine system extends beyond the well-known inhibition of the renin-angiotensin-aldosterone system and includes increased adrenergic activity and cortisol concentrations. This neuroendocrine activation might impact the outcome of therapeutical BNP administrations and should be further investigated in conditions associated with increased BNP secretion.

NEW & NOTEWORTHY The heart hormone B-type natriuretic peptide (BNP) is increased in patients with heart failure, where it is thought to have beneficial effects by reducing the preload. Here we report that intravenous administration of BNP in men leads to increases in adrenal hormones cortisol, epinephrine, and norepinephrine. Cortisol and catecholamine levels are independent predictors of increased cardiovascular mortality risk; therefore, drugs targeting the BNP system should be evaluated regarding their effects on the neuroendocrine activation accompanying heart failure.

9p21.3 risk locus is associated with first-ever myocardial infarction in an Austrian cohort

AIMS

Atherosclerosis often presents as a complex systemic disease that is strongly influenced by lifestyle factors, but also by the genetic background. The sequence variant rs1333049 affects the expression of ANRIL, a noncoding RNA transcript playing a key role in the regulation of inflammatory processes. We thus aimed to replicate the predictive value of genetic information on this variant regarding the development of cardiovascular events in an Austrian high-risk cohort.

METHODS

Nine hundred and eighty-eight patients from an angiologic outpatient ward at a large University hospital were genotyped by means of the 5'-nuclease assay. Relative risk ratios were assessed for carriers of different alleles. Statistical independence of genetic information was evaluated in multivariable analysis including known risk markers.

RESULTS

In patients carrying the [G]-allele, metabolic parameters (serum low-density lipoprotein, total cholesterol) significantly decreased during the initial 6 months of the observation period (P < 0.01). Likewise, homozygous [C]-allele carriers were at a higher risk of suffering myocardial infarction (relative risk = 2.681, 95% confidence interval 1.418-5.070). In contrast, we found no interaction between rs1333049 genotype and progression of carotid atherosclerosis or stroke.

CONCLUSIONS

These results are in line with the previous findings, suggesting that genetic information on the rs1333049 variant might be a useful predictor of adverse cardiac events. Thus, we could successfully replicate the predictive value of the 9p21 risk allele in an Austrian cohort.

Effects of B-type natriuretic peptide on cardiovascular biomarkers in healthy volunteers

Cardiovascular biomarkers provide independent prognostic information in the assessment of mortality and cardiovascular complications. However, little is known about possible interactions between these biomarkers. In the present study, we evaluated the influence of B-type natriuretic peptide (BNP) on midregional-proadrenomedullin (MR-proADM), C-terminal-proendothelin-1 (CT-proET-1), growth differentiation factor-15 (GDF-15), midregional-proatrial natriuretic peptide (MR-proANP), copeptin, and procalcitonin in healthy volunteers. Ten healthy male subjects (mean age 24 yr) participating in a randomized, placebo-controlled, single-blinded crossover study received placebo or 3.0 pmol·kg−1·min−1human BNP 32 during a continuous infusion lasting for 4 h. Effects of BNP on other cardiovascular biomarkers were assessed. BNP did not change concentrations of MR-proADM, copeptin, CT-proET1, GDF-15, or procalcitonin. In contrast, MR-proANP was significantly decreased during BNP infusion. BNP as an established cardiovascular biomarker did not affect plasma concentrations of other cardiovascular biomarkers in a model of healthy volunteers.

Observation of a reflected shock in an indirectly driven spherical implosion at the national ignition facility

A 200  μm radius hot spot at more than 2 keV temperature, 1  g/cm^{3} density has been achieved on the National Ignition Facility using a near vacuum hohlraum. The implosion exhibits ideal one-dimensional behavior and 99% laser-to-hohlraum coupling. The low opacity of the remaining shell at bang time allows for a measurement of the x-ray emission of the reflected central shock in a deuterium plasma. Comparison with 1D hydrodynamic simulations puts constraints on electron-ion collisions and heat conduction. Results are consistent with classical (Spitzer-Harm) heat flux.

B-type natriuretic peptide modulates ghrelin, hunger, and satiety in healthy men

Chronic heart failure is accompanied by anorexia and increased release of B-type natriuretic peptide (BNP) from ventricular cardiomyocytes. The pathophysiological mechanisms linking heart failure and appetite regulation remain unknown. In this study, we investigated the impact of intravenous BNP administration on appetite-regulating hormones and subjective ratings of hunger and satiety in 10 healthy volunteers. Participants received in a randomized, placebo-controlled, crossover, single-blinded study (subject) placebo once and 3.0 pmol/kg/min human BNP-32 once administered as a continuous infusion during 4 h. Circulating concentrations of appetite-regulating peptides were measured hourly. Subjective ratings of hunger and satiety were evaluated by visual analog scales. BNP inhibited the fasting-induced increase in total and acylated ghrelin concentrations over time (P = 0.043 and P = 0.038, respectively). In addition, BNP decreased the subjective rating of hunger (P = 0.009) and increased the feeling of satiety (P = 0.012) when compared with placebo. There were no significant changes in circulating peptide YY, glucagon-like peptide 1, oxyntomodulin, pancreatic polypeptide, leptin, and adiponectin concentrations. In summary, our results demonstrate that BNP exerts anorectic effects and reduces ghrelin concentrations in men. These data, taken together with the known cardiovascular properties of ghrelin, support the existence of a heart-gut-brain axis, which could be therapeutically targeted in patients with heart failure and obesity.

A simple micro-photometric method for urinary iodine determination

BACKGROUND

Urinary iodide concentration (UIC) is useful to evaluate nutritional iodine status. In clinical settings UIC helps to exclude blocking of the thyroid gland by excessive endogenous iodine, if diagnostic or therapeutic administration of radio-iodine is indicated. Therefore, this study established a simple test for the measurement of UIC.

METHODS

UIC was analyzed in urine samples of 200 patients. Samples were pre-treated at 95°C for 45 min with ammonium persulfate in a thermal cycler, followed by a photometric Sandell-Kolthoff reaction (SK) carried out in microtiter plates. For method comparison, UIC was analyzed in 30 samples by inductivity coupled plasma mass spectro-metry (ICP-MS) as a reference method.

RESULTS

Incubation conditions were optimized concerning recovery. The photometric test correlated well to the reference method (SK=0.91*ICP-MS+1, r=0.962) and presented with a functional sensitivity of 20 μg/L. UIC of patient samples ranged from <20 to 750 μg/L (median 110 μg/L); 90% of the urine samples had iodide concentrations below 210 μg/L.

CONCLUSION

The modified SK-test takes approximately 90 min for analyses of 20 urine samples compared with 27 h for ICP-MS. The photometric test provides satisfactory results and can be performed with the basic equipment of a clinical laboratory.

Changes in osteopontin and in biomarkers of bone turnover during human endotoxemia

Systemic infection and inflammation in men are associated with bone loss. Rodent studies have elucidated the pathways mediating the effects of bacterial lipopolysaccharide (LPS), activated immune cells and hormones on bone. Here we investigate the changes in biochemical parameters of bone turnover following human endotoxemia, an experimental model of self-limiting systemic infection and inflammation. Ten healthy men received in a randomised, placebo-controlled, cross-over trial once placebo and once 2 ng/kg Escherichia coli endotoxin (LPS). During the following 6 h we monitored parathyoid hormone (PTH) and osteopontin (OPN), a multifunctional protein related to bone pathophysiology, as well as biochemical markers of bone turnover: C-terminal telopeptide of type I collagen (CTX), N-terminal propeptide of type I collagen (P1NP) and osteocalcin (OC). In LPS sessions there was a transient fall in PTH at 3 h (p=0.009) and a nearly two-fold increase in OPN levels after 6 h (LPS: 155+/-19 pg/ml; placebo: 85+/-13 pg/ml, p<0.001). LPS gradually reduced CTX levels (LPS: 0.44+/-0.4 pg/ml; placebo: 0.59+/-0.06 pg/ml, p=0.003), P1NP showed a peak at 4 h (LPS: 89.9+/-14.7 pg/ml; placebo: 75+/-9.7 pg/ml, p=0.028) and circulating OC did not change. The early human response to systemic endotoxemia boosts osteopontin levels and modifies bone biomarkers, indicating a decrease in the lytic activity of osteoclasts, accompanied by an increase in the activity of immature osteoblasts. These changes might present the acute phase response of immune and bone cells to bacterial stimuli in men.

Sex differences in the association between albumin and all-cause and vascular mortality

BACKGROUND

Low serum albumin levels are associated with cardiovascular disease and mortality risk. This study evaluated the predictive value of low serum albumin for all-cause-mortality in a large Viennese patient cohort and investigated sex differences in the association between serum albumin and mortality.

MATERIALS AND METHODS

Serum albumin concentrations of 285 930 patients, who attended the General Hospital Vienna between 1992 and 2002, were evaluated and linked with the Austrian Death Registry. The median observation period was 7.4 +/- 4.0 years and the death rate was 16.8%. For Cox regression analysis, albumin levels were divided into deciles, the highest category served as reference value. To analyse associations between albumin and mortality independent of liver function, results were adjusted for cholinesterase, which indicates protein synthesis capacity of the liver.

RESULTS

Hazard ratios for all-cause-mortality increased linearly with decreasing albumin levels from 1.05 in the 9th to 2.98 in the 1st decile. Adjusted for cholinesterase, the relative risk for mortality was still 1.91 in the lowest category. Compared with women, men had an average 50% increased risk of death in almost every decile, adjusting for cholinesterase reduced the sex difference to a 10-20% higher mortality risk for men. In critically ill patients, hazard ratios for all-cause-mortality ranged from 4.5 in the 9th decile to 9.5 in the lowest albumin category.

CONCLUSION

This study demonstrates a strong inverse association between serum albumin and mortality in a large patient cohort. The predictive value of low albumin was remarkably higher in men than in women.

Assessment of oxygen-consumption by use of reverse Fick-principle and indirect calorimetry in critically ill patients

Oxygen consumption was measured simultaneously by the reverse Fick-principle (V02FICK) and by indirect calorimetry ("Metabolic Measurement Cart Horizon") (V02MMC) in 31 critically ill patients; 24 men and 7 women. Seventeen patients were breathing spontaneously, 14 patients were on mechanical ventilation. The fractional inspiratory oxygen concentration (FI02) in ventilated patients ranged from 0.21 to 0.4 (mean 0.302). Total oxygen consumption as measured by indirect calorimetry was 286.7 +/- 59.7 ml/min (mean +/- SD), and measured by reverse Fick-principle 258.9 +/- 52.2 ml/min (mean +/- SD). The coefficient of correlation between the two methods was r = 0.873. The absolute difference of oxygen consumption between reverse Fick-method and indirect calorimetry was 11.3%. Regression analysis according to Theil revealed a similar regression between spontaneously breathing and mechanically ventilated patients for the studied FI02 values below 0.4. It is concluded that indirect calorimetry is a reliable method for measuring oxygen consumption in spontaneously breathing as well as mechanically ventilated critically ill patients.

Development of a new calcium phosphate powder-binder system for the 3D printing of patient specific implants

A key requirement for three-dimensional printing (3-DP) of medical implants is the availability of printable and biocompatible powder-binder systems. In this study we developed a powder mixture comprising tetracalcium phosphate (TTCP) as reactive component and beta-tricalcium phosphate (beta-TCP) or calcium sulfate as biodegradable fillers, which can be printed with an aqueous citric acid solution. The potential of this material combination was demonstrated printing various devices with intersecting channels and filigree structures. Two post-processing procedures, a sintering and a polymer infiltration process were established to substantially improve the mechanical properties of the printed devices. Preliminary examinations on relevant application properties including in vitro cytocompatibility testing indicate that the new powder-binder system represents an efficient approach to patient specific ceramic bone substitutes and scaffolds for bone tissue engineering.

Receptor activator of nuclear factor kappaB ligand and osteoprotegerin in men with thyroid cancer

BACKGROUND

Suppressive thyroid hormone therapy is generally a lifelong treatment for patients with differentiated thyroid cancer (DTC). However, long-standing thyrotropin (TSH) suppression is a risk factor for osteoporosis. Osteoprotegerin (OPG) and receptor activator of nuclear factor kappaB ligand (RANKL) are central regulators of bone turnover. The aim was to analyze the effects of a suppressive thyroid hormone therapy in males with DTC on the OPG/RANKL system and on bone metabolism.

PATIENTS AND METHODS

The OPG and soluble RANKL (sRANKL) were determined in 40 men (mean age, 53.2 years) with DTC on suppressive thyroid hormone therapy (TSH; 0.053 +/- 0.037 mU L(-1), duration 5.7 +/- 4.4 years) and 120 healthy controls matched for age. The markers of bone metabolism were C-terminal telopeptide of type I collagen in serum (sCTx) and osteocalcin (OC).

RESULTS

The control group had OPG values (mean +/- SD) of 1.9 +/- 1.0 pmol L(-1) and sRANKL values of 0.40 +/- 0.62 pmol L(-1). In patients with DTC, results for OPG were 3.03 +/- 1.04 pmol L(-1) (P < 0.05) and for sRANKL were 0.13 +/- 0.16 pmol L(-1) (P < 0.05). The control group presented values for sCTx of 2669 +/- 1132 pmol L(-1) and for OC of 17.89 +/- 6.5 ng mL(-1). Patients with DTC on suppressive thyroid hormone therapy had increased sCTx values of 3810 +/- 2020 pmol L(-1) (P = 0.03) but comparable OC values of 19.21 +/- 7.67 ng mL(-1) (NS).

CONCLUSIONS

Suppressive thyroid hormone therapy in men with DTC increased bone degradation and induced significant changes in the OPG/RANKL system. These changes include, besides the risk of osteoporosis, possible negative effects on the vascular function and an increased risk of cardiovascular disease.

[Three-dimensional vectorcardiography to predict CRT-responder]

Cardiac resynchronization therapy (CRT) is an accepted treatment for congestive heart failure (NYHA III-IV), but a substantial number of patients show no response to therapy. LBB, QRS width and echocardiographic measurements are parameters for indication, but they are not valid to predict hemodynamic response. A new method based on vector ECG analysis can deliver additional information, such as: parts or areas with late excitation, and with slow or fast depolarization speed. Electrical excitation is a prerequisite for contraction; this leads to the hypothesis that areas with late electrical activation will contract later. Algorithms for analysis of the vector ECG (determination of the vector -- time, area and speed) may help to identify responders and non-responders.

[A simple method for AV-delay determination in dual chamber pacemakers]

The individual adjustment of the AV intervals is a prerequisite for the hemodynamic advantages of dual-chamber pacing. The methods for the optimization of the AV-Delay (AVD) applied so far are time intensive. A simple and fast method is the approximate adjustment of the AVD with the surface-ECG. The aim of this work is the conception and validation of this new method. The optimal AVD is given if at the end of the atrial contraction the mitral valve is closed by the ventricular increase of pressure. In order to achieve this with pacemaker patients, the individually different atrial and ventricular conduction times must be considered. The different conduction times can be determined from the surface-ECG. Intra- and interatrial conduction times can be defined by the beginning of the atrial spike up to the end of the p-wave. The beginning of ventricular pressure increase corresponds to the peak of the stimulated QRS complex (beginning of the Iso-Volumetric Contraction time, ISVC) and depends on the interventricular conduction time.¶   In the case of 100 patients, who did not receive a cardiac pacemaker, the interval at the end of the p-wave (left atrial excitation, EP) up to the peak of the r-wave (ISVC) during rest and exercise was measured and an age referred average value of 100ms determined; this serves as standard value if no AV-conduction is available. The approximated optimized AVD is given if the interval of the end at the p-wave to the peak of the QRS-Complex amounts to 100ms. By means of a simple algorithm, the optimized AVD can, thus, be calculated:¶   After programming a long AVD, the interval at the end of the native or paced p-wave up to the peak of the stimulated QRS-Complex (EP/ISVC) is determined. This value EP/ISVC is then taken from the long AVD, the 100ms standard value is added and one receives the approximately optimized AVD.¶   In order to validate the described method, 13 consecutive patients (2 female, 11 male, average age 67±7.8 years) were included, and received for different indication (7 sick sinus syndrome, 4 AV block III, 2 binode disease) a DDD pacemaker (Affinity, St. Jude Medical).¶   About 8 weeks after implantation all patients underwent a PA catheter investigation, in order to optimize the AV-/PV-Delay of the pacemaker regarding the maximum cardiac output (CO). For CO measurement the thermo dilution method was applied. Altogether 17 complete hemodynamic measurements (9 times with different PVDs, 8 times with different AVDs) were executed. The patients 10-13 could be examined both in the VDD and in the DDD mode.¶   The minimum determined CO amounted to 3.5 l/min, the maximal CO 7.1 l/min and the average value was 5.62±0.98 l/min. In all patients not only one optimal AVD was found but, moreover, a varied interval of AVDs with which optimal CO results could be obtained. The comparison of surface ECG optimized AVD with the PA catheter optimized AVD showed a statistically significant correlation (0.825PV, 0.982 AV, P<0.01). Sixteen out of seventeen measurements were at an interval which enables hemodynamic optimal CO or stroke volume. Only one AVD determined from the surface ECG was situated slightly (10 ms) outside of a hemodynamic optimal determined AVD. Despite the encouraging test results represented here, further studies should examine the value of the new algorithm in comparison with the other techniques for AVD optimization.

Metabolic encephalopathy in critically ill patients suffering from septic or nonseptic multiple organ failure

OBJECTIVE

Evaluation of changes in the peak latencies of sensory evoked potentials in different patient groups, to evaluate differences in metabolic encephalopathy of critically ill patients with multiple organ failure as a result of septic or nonseptic conditions.

DESIGN

Prospective cohort study.

SETTING

Intensive care units of the university hospital, Vienna.

PATIENTS

Patients (n = 103) treated on an intensive care unit because of multiple organ failure with additional metabolic encephalopathy. Multiple organ failure was induced by sepsis (group A; n = 56), surgery (group B; n = 29), or both (group C; n = 18).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Metabolic encephalopathy was determined by measuring median nerve-stimulated short-latency and long-latency sensory evoked potentials. No differences in the peak latencies of the sensory evoked potentials were detected among the groups. Septic patients had a N70 peak latency of 131+/-21 msecs, nonseptic postsurgical patients of 132+/-17 msecs, and septic postsurgical patients of 134+/-17 msecs. The cervicomedullary N13 to cortical N20 conduction times were 6.4+/-1 msec, 6.4+/-1.4 msecs, and 6.8+/-1.2 msecs, respectively. All measured peak latencies were significantly prolonged compared with peak latencies of healthy controls. The severity of illness assessed by the Acute Physiology and Chronic Health Evaluation III score was not different between the three groups. An increase of the delay of N70 peak latencies was significantly correlated with the severity of illness (r2 = .15; p < .00005).

CONCLUSION

There was no difference in sensory evoked potential measurements detectable among septic patients with multiple organ failure, nonseptic postsurgical patients with multiple organ failure, and septic postsurgical patients with multiple organ failure. The N70 peak latency was significantly correlated with the severity of illness but not with the presence or absence of sepsis. In postsurgical patients with multiple organ failure and superimposed sepsis, the N70 peak latencies were not further prolonged compared with postsurgical patients without sepsis.

Improved outcome prediction in unconscious cardiac arrest survivors with sensory evoked potentials compared with clinical assessment

OBJECTIVE

To compare the prognostic ability of sensory evoked potentials in cardiac arrest survivors with the outcome predicted by a panel of experienced emergency physicians based on detailed prehospital, clinical, and laboratory data.

DESIGN

Inception cohort study.

SETTING

Medical intensive care unit and department of emergency medicine at a university hospital.

PATIENTS

A total of 162 unconscious, mechanically ventilated patients who survived > or =24 hrs after resuscitation from cardiac arrest.

INTERVENTIONS

Recording of sensory evoked potentials and outcome prediction after review of detailed clinical and laboratory data by emergency physicians within 24 hrs after cardiac arrest.

MEASUREMENTS AND MAIN RESULTS

At 6 months, the outcome of 36 patients was classified as favorable and 126 patients were rated as poor. After review of prehospital data, emergency physicians predicted favorable vs. poor outcome with a sensitivity of 70% and a specificity of 65%. After additional assessment of data 1 hr after cardiac arrest, the sensitivity of emergency physician predictions increased to 80%, whereas the specificity decreased to 48%. Outcome prediction by emergency physicians was most accurate after obtaining detailed patient data 24 hrs after cardiac arrest (sensitivity, 81%; specificity, 58%). In 35 of 36 patients with favorable outcomes, the cortical evoked potential N70 peak was detected between 72 and 128 msec. Of 113 patients with an N70 peak latency >130 msec or an absent N70 peak, all except one had a poor outcome. By using a cutoff of 130 msec, the N70 peak latency alone had a sensitivity of 94% and a specificity of 97%. The predictive accuracy of the N70 peak latency was significantly higher than the clinical assessment 24 hrs after cardiac arrest (91% vs. 76%, p = .0003).

CONCLUSION

In unconscious cardiac arrest survivors, a recording of long-latency sensory evoked potentials is more accurate in predicting individual outcome than an emergency physician review of clinical data.

[Secondary prevention following coronary intervention. Survey of 13 intervention centers in Austria]

Risk factor control has been shown to reduce the incidence of coronary events in patients with or without preceding infarction. Secondary prevention should therefore be borne in mind by every cardiologist. In order to test this concept and/or to promote secondary prevention in our country, the following survey was conducted by our working group for epidemiology and prevention. All interventional centres of the country (7 million inhabitants) were asked to report relevant data of 50 consecutive patients with PTCA in a structured questionnaire. Thirteen centres responded and we report the data of 650 patients. The mean proportion of women was 28%, the mean age 61.1 years and the mean stent rate 49.8%. The indications for PTCA varied widely: stable angina 10-74%, unstable angina 10-86%, primary PTCA 0-22%. The risk factor history was distributed as follows: diabetes 12-46% (mean 22.3%), hypertension 32-68% (mean 54.2%), current smoking 6-56% (mean 21.9%), and total cholesterol (TChol) > 200 mg/dl: 30-78% (mean 60.3%). Current lipid values were available for T chol. in 44-100% (mean 84.5%) and for LDL in 4-100% (mean 67.1%). Dietary counselling by a dietician was done in 4-100% of patients (mean 35.6%) Information concerning the hazards of smoking was given to 25-100% (mean 83.6%) of current smokers. Drug treatment at hospital discharge was as follows: 84-100% (mean 93.1%) received ASA, 24-74% (mean 49.8%) ticlopidine, 6-84% (mean 53.3%) nitrates, 34-82% (mean 60.2%) beta blockers, 10-70% (mean 39.5%) ACE inhibitors, 4-74% (mean 4 7.2%) lipid lowering drugs, 7-48% (mean 17.8%) calcium antagonists, 0-12% (mean 6.1%) digitalis and 0-28% (mean 13.6%) diuretics. Follow-up data were collected in 4 centres at 6 months post discharge and were available for 174 patients. Here we found an increase in the prescription of calcium antagonists, digitalis and statins. The following conclusions were drawn at a conference in which all centres participated: lipid values should be available for each patient at PTCA, dietary counselling should be initiated for every patient during hospitalisation (and continued by the family physician) and the national cardiac society should promote guidelines for the use of drugs in which the variation in use is too wide at present. It should be ensured that these guidelines are implemented not only in patients after AMI but also in those after PTCA.

Attenuation correction improves the detection of viable myocardium by thallium-201 cardiac tomography in patients with previous myocardial infarction and left ventricular dysfunction

The aim of this study was to determine the influence of attenuation-corrected thallium-201 stress/redistribution/reinjection single-photon emission tomography (SPET) on the number of viable segments in patients with previous myocardial infarction and dysfunctional myocardium. Fifty-one patients with previous myocardial infarction and left ventricular dysfunction were included in the study. In all patients, 201Tl non-corrected (NC) and attenuation-corrected (AC) SPET was performed using a stress/redistribution/reinjection protocol followed by coronary angiography. A semiquantitative analysis was performed using polar maps for NC and AC stress, redistribution and reinjection short-axis and vertical long-axis (apex) slices. Severe (perfusion defect below 50%/maximal count rate: PD < 50), mild and moderate persistent defects for redistribution and reinjection were evaluated for both NC and AC studies. A total of 1581 segments were evaluated by semiquantitative segmental analysis for both NC and AC studies for each redistribution and reinjection map. In the redistribution maps, NC revealed a total of 352 segments and AC a total of 222 segments with impaired perfusion below 50% of the maximal count rate (PD < 50). The mean number of affected segments was 6.9 +/- 5.5 in the case of NC and 4.4 +/- 4.8 in the case of AC (P < 0.001). In the reinjection maps, NC revealed a total of 263 non-viable segments (PD < 50) and AC a total of 169 non-viable segments. The mean number of affected segments was 5.2 +/- 5.3 in the case of NC and 3.3 +/- 4.2 in the case of AC (P < 0.001). Recovery of function was better predicted by AC than by NC in 20% of patients in the follow-up group. Therefore, the use of attenuation correction influences the extent of viable segments by showing more viable segments in either redistribution or reinjection maps. 201Tl imaging without attenuation correction may underestimate the extent of tissue viability, which may contribute to the lower sensitivity compared to fluorine-18-fluorodeoxyglucose positron emission tomography, where attenuation correction is a routinely performed procedure.

Previous episodes of hypoglycemic coma are not associated with permanent cognitive brain dysfunction in IDDM patients on intensive insulin treatment

Intensive insulin treatment of IDDM is associated with increased frequency of hypoglycemic coma. The extent of possible cerebral sequelae after recovery is still unknown. We studied the impact of previous hypoglycemic coma on neurophysiological measures of cognitive brain function in 108 patients with adult-onset IDDM receiving intensive insulin treatment. In the study, 55 IDDM patients (age 38 +/- 14 years, mean +/- SD) who had a history of > or =1 (median 3, range 1-35) comatose hypoglycemic event were compared with 53 IDDM patients (age 34 +/- 12 years) with no history of hypoglycemic events using P300 event-related potentials and psychometric tests (the Mini-Mental State Exam and trailmaking test, part A). Findings on these patients were compared with those from 108 matched healthy control subjects. No difference was observed in P300 latencies and psychometric tests between patients with and without a history of hypoglycemic coma (P300 latency, 346 vs. 342 ms; trailmaking test, 31 vs. 30 s; Mini-Mental State Exam, 29.5 vs. 29.6; NS). In diabetic patients, however, P300 latencies were delayed compared with those of healthy control subjects (344 vs. 332 ms; P < 0.001) and were correlated to diabetes duration but not to total hypoglycemic episodes. Scores on the Mini-Mental State Exam (29.5 vs. 29.6; P = 0.59) and trailmaking test (31 vs. 28 s; P = 0.10) were not different between patients and control subjects. In conclusion, previous episodes of hypoglycemic coma are not associated with permanent impairment of cognitive brain function in patients with adult-onset IDDM receiving intensive insulin treatment compared with patients without such episodes. Cognitive brain function, however, is subclinically impaired in relation to duration of diabetes.

Hardware Description Language for Optical Processing (hadlop): a Simulation Environment for Parallel Optoelectronic Architectures

We present a simulation environment for parallel optoelectronic data-processing systems, and we especially consider the fusion of optoelectronic integrated circuits and optical interconnection modules. hadlop, which stands for hardware description language for optical processing, is a simulator that works at the digital design level. So far, hadlop has allowed algorithm and architecture studies for smart-pixel systems. We have just begun to extend the capabilities of hadlop toward an automatic synthesis tool for three-dimensional optoelectronic VLSI circuits. A hadlop architecture will then be the basis for the automatic generation of detailed construction plans that consider the interaction between optical interconnection modules and optoelectronic integrated circuits. The simulation system is freeware and is available through the Internet at http://www2.informatik.uni-jena.de/pope/HADLOP/hadlop.html.

Attenuation-corrected thallium-201 single-photon emission tomography using a gadolinium-153 moving line source: clinical value and the impact of attenuation correction on the extent and severity of perfusion abnormalities

The aim of the study was to test the clinical value of attenuation-corrected (AC) thallium-201 single-photon emission tomography using a moving gadolinium-153 line source in a group of patients in whom coronary angiography was planned because of clinically suspected coronary artery disease (CAD). Furthermore, we wanted to test the impact of AC on assessment of the extent and severity of perfusion abnormalities. A total of 107 patients planned to undergo coronary angiography were included in the study. In each patient, AC and NC (non-corrected) 201Tl SPET was performed. AC and NC images were evaluated visually as well as by a 31-segment semiquantitative analysis and the findings were correlated with angiographic results. Patients were assigned to two groups: group A with angina and no previous cardiac infarction or intervention and group B with known CAD because of previous myocardial infarction or intervention. With visual analysis, NC revealed a sensitivity of 88.9% in group A and 74.3% in group B, compared to 94.4% in group A and 94.3% in group B with AC. Specificity for NC was calculated to be 68.7% for group A and 91.3% for group B. AC demonstrated significantly higher specificity of 83.9% and 100% respectively. This effect was particularly demonstrated for males and bicycle workload. The extent and severity of perfusion abnormalities were significantly influenced by the use of AC, in that significantly fewer abnormal and less severely abnormal segments were demonstrated in the segmental analysis as compared to NC; this was especially true for the vascular territory of the left anterior descending artery and the right coronary artery. It is concluded that AC with a moving line source is feasible in patients with all degrees of probability of CAD. AC has a significant impact on the assessment of the severity and extent of myocardial ischaemia, especially in the posterior and septal wall.

Gastric rupture--an uncommon complication after successful cardiopulmonary resuscitation: report of two cases

Gastric rupture is a poorly described complication following cardiopulmonary resuscitation. An incidence of 0.1% has been reported in the literature. Published reports describe traumatic gastric rupture after use of the CardioPump, after mouth-to-mouth ventilation, and in children after resuscitation performed by paramedics. We report on two patients who developed gastric rupture after successful standard cardiopulmonary resuscitation. Preexisting gastric ulcerations or osseous trauma during resuscitation had been excluded. Neither patient developed abdominal symptoms; in both cases the gastric rupture was diagnosed by routine chest X-ray and both patients underwent-after stabilization-surgical treatment. One patient recovered well, but the other developed cardiogenic shock due to malignant arrhythmias and severely impaired left ventricular function. This patient died on the 6th postinterventional day. Gastric rupture rarely occurs after cardiopulmonary resuscitation. The causes of gastric rupture and the means to avoid this complication will be discussed.

Wilson's disease in patients presenting with liver disease: a diagnostic challenge

BACKGROUND & AIMS

In patients with Wilson's disease presenting with liver involvement, the correct diagnosis is often missed or delayed. The aim of this study was to find an algorithm for diagnosis of this difficult patient group.

METHODS

Clinical and laboratory findings of 55 patients with Wilson's disease were evaluated at diagnosis before treatment. Presenting symptom was chronic liver disease in 17 patients, fulminant hepatic failure in 5 patients, hemolysis in 3 patients, and neurological disease in 20 patients, and 10 patients were detected by family screening (siblings). Evaluation included neurological and ophthalmologic examination, routine laboratory tests, and parameters of copper metabolism including liver copper content in 43 liver biopsy specimens.

RESULTS

In the whole group, serum ceruloplasmin level was <20 mg/dL in 73%, urinary copper excretion was increased in 88%, and liver copper content was elevated in 91% at diagnosis. Kayser-Fleischer rings were detected in 55%. In contrast to patients with neurological disease (90% Kayser-Fleischer rings, 85% low ceruloplasmin), only 65% of patients presenting with liver disease were diagnosed by these typical findings. Ceruloplasmin levels were lower in patients with Kayser-Fleischer rings or with neurological disturbances than in patients without these symptoms.

CONCLUSIONS

The commonly used clinical and laboratory parameters are not sufficient to exclude the diagnosis of Wilson's disease in patients with liver disease of unknown origin.

Detection of subclinical brain dysfunction by sensory evoked potentials in patients with severe diabetic ketoacidosis

OBJECTIVE

Subclinical brain dysfunction is a potentially deleterious complication of diabetic ketoacidosis but is rarely recognized. Thus, we investigated the diagnostic value of sensory evoked potentials for detecting subclinical brain dysfunction in patients with diabetic ketoacidosis.

DESIGN

Prospective trial.

SETTING

Intensive care unit in a university hospital.

PATIENTS

5 neurologically asymptomatic patients (Glasgow Coma Scale score 15, slight drowsiness; aged 20 to 66 years) with an established diagnosis of severe diabetic ketoacidosis were studied.

MEASUREMENTS AND RESULTS

Short- and long-latency sensory evoked potentials were recorded within 2 h of initiation of therapy for ketoacidosis and 7 days after normalization of ketoacidosis, respectively. Two hours after starting therapy, sensory evoked potential peak latencies were prolonged in all five patients compared to age-matched healthy subjects [cervical N 13 to cortical N 20 interpeak latency of short-latency evoked potentials (mean) 5.8 vs 5.3 ms, p < 0.05; N 35 peak latency 40 vs 34 ms, p < 0.05; N 70 peak latency of long-latency evoked potentials 102 vs 76 ms, p < 0.01]. In all five patients, cervical N 13 to cortical N 20 interpeak latency and N 35 and N 70 peak latency reverted to normal 7 days after recovery from diabetic ketoacidosis.

CONCLUSIONS

Our study indicates that the recording of sensory evoked potentials is a sensitive method of detecting subclinical brain dysfunction in patients with severe diabetic ketoacidosis. Since sensory evoked potentials were significantly prolonged in all five patients, this strongly suggests that subclinical brain dysfunction occurs more frequently than is generally recognized.

[Modification of axial length and astigmatism by scleral buckling surgery]

BACKGROUND

Scleral buckling surgery for retinal detachment alters the shape of the globe resulting in changes of the refractive state of the eye.

MATERIALS AND METHODS

In a prospective study of 52 eyes with retinal detachment we examined changes of corneal astigmatism and axial length induced by encircling buckling or segmental buckling spanning two quadrants. We compared our results with those found in literature.

RESULTS

In most patients we found a shortening of the globe, rather in cases with encircling buckles than in the cases with segmental buckles (parallelly to the limbus). We also saw changes in astigmatism postoperatively in all patients. There was no statistically significant difference between patients with encircling and segmental buckles fixed parallelly to the limbus, neither in the change of axial length nor in the change of astigmatism.

CONCLUSIONS

In all cases of scleral buckling procedures changes of corneal astigmatism and axial length are to be expected. So our results differ from those of other authors who did not always find a change of astigmatism. We suppose that the authors of the publications which differ from our results did not consider the change of the corneal axis by using the vector method.

Cyclosporine may affect improvement of cognitive brain function after successful cardiac transplantation

BACKGROUND

The effects of cardiac transplantation on cognitive brain function are uncertain.

METHODS AND RESULTS

We measured cognitive brain function and quality of life in out-of-hospital cardiac transplant candidates (n = 55; ejection fraction, 19.9%; age, 54.8 years [means]). After transplantation, the patients were serially reevaluated at 4 months (n = 25) and at 12 months (n = 19). Brain function was measured objectively by cognitive P300 evoked potentials. Additionally, standard psychometric tests (Trail Making Test A, Mini-Mental State Examination, and Profile of Mood State test) were performed. Cognitive P300 evoked potentials were impaired in cardiac transplant candidates (359 ms, recorded at vertex) compared with 55 age- and sex-matched healthy subjects (345 ms, P < .01). Trail Making Test A was also abnormal (45 versus 31 seconds in 55 healthy subjects, P < .01). After transplantation, P300 measures were normalized at 4 months (345 ms, P < .05 versus before transplantation) but declined again at 12 months (352 ms, P = NS versus before transplantation). Stepwise multiple regression analysis revealed that cumulative cyclosporine dosage was the only predictor of individual cognitive brain function 4 months (753 mg/kg body wt, P < .05) and 12 months (2006 mg/kg body wt, P < .01) after transplantation, respectively.

CONCLUSIONS

Objective cognitive P300 auditory evoked potential measurements indicate that cognitive brain function is significantly impaired in patients suffering from stable end-stage heart failure. Successful cardiac transplantation is effective to fully normalize impaired brain function. Subsequent relative long-term decline of cognitive brain function after successful cardiac transplantation is strongly suggested to be related to cumulative cyclosporine neurotoxicity.

Detection of nontraumatic comatose patients with no benefit of intensive care treatment by recording of sensory evoked potentials

OBJECTIVES

To determine the predictive ability of sensory evoked potential recordings in nontraumatic comatose patients. To evaluate the hypothesis that patients with bilateral absent cortical responses ultimately die despite long-term intensive care treatment.

DESIGN

Prospective cohort study.

SETTING

Medical intensive care unit (ICU) of a university hospital.

PATIENTS

Four hundred forty-one adult nontraumatic comatose patients (unarousable unresponsiveness to external stimulation, Glasgow Coma Score < or = 7) from various causes. Six hundred seventy-six sensory evoked potential measurements were performed within 7 days after onset of coma.

MAIN OUTCOME MEASURES

Death or survival to hospital discharge.

RESULTS

Eighty-six patients (20%) had a bilateral loss of the cortical evoked potential N20 peak. Despite long-term intensive care treatment, all died without awakening from coma (mortality rate, 100%; 95% confidence interval, 96-100). The mean stay at the ICU after evoked potential measurement until death was 8.1 days (697 patient days). The overall cost of ICU management for these 86 patients accounted for approximately $1,324,300. In the remaining 355 comatose patients with preserved cortical N20 peak, 148 (42%) survived and 207 (58%) died. In this latter group of patients, cervicomedullary N13 to cortical N20 conduction time was prolonged in nonsurvivors (mean +/- SD, 6.7 +/- 1.3 milliseconds) compared with that in survivors (mean +/- SD, 6.4 +/- 1.2 milliseconds, P < .05) and healthy controls (mean +/- SD, 5.5 +/- 0.4 milliseconds, P < .05). Although this difference is statistically significant, a preserved N20 peak is not useful to discriminate whether the individual patient will survive (N13-N20 conduction time of > 7 milliseconds had a positive predictive value of correct prediction of death of 0.67).

CONCLUSIONS

Recording of sensory evoked potentials identifies a subgroup of adult nontraumatic comatose patients with a mortality rate of 100% in our sample. In these patients, advanced intensive care treatment should be withdrawn to provide limited ICU resources for patients with higher probability of favorable outcome. We emphasize that these results are not applicable to comatose patients following closed head trauma and particularly not to children.

Beneficial effect of renal transplantation on cognitive brain function

Cognitive brain dysfunction is a common complication of end-stage renal disease. To investigate the cerebral effect of renal transplantation, we studied P300 event-related potentials--an objective marker of cognitive brain function--trailmaking test and Mini-mental state in 15 chronic hemodialysis patients and 45 matched healthy subjects. Before transplantation, patients showed prolonged P300 latency (364 vs. 337 ms, P < 0.01), smaller amplitude (15.2 vs. 19.1 microV) and scored lower (P < 0.05) in trailmaking test and Mini-mental state as compared to healthy subjects. Following renal transplantation (14 months), P300 latency decreased (337 ms, P < 0.01 vs. before) and amplitude increased (17.4 microV, P < 0.05 vs. before), indicating improved cognitive brain function. The trailmaking test and Mini-mental state tended to improve. Following transplantation, P300 findings, trailmaking test and Mini-mental state were not different from healthy subjects. Additional studies following erythropoietin treatment in 6 of the 15 hemodialysis patients revealed decreased (improved) P300 latency (351 vs. 379 ms before, P < 0.05) with further decrease following transplantation (341 ms, P = 0.06). Our findings indicate that cognitive brain dysfunction in hemodialysis patients may be fully reversed by successful renal transplantation.

The impact of implantable cardioverter-defibrillators on mortality among patients on the waiting list for heart transplantation

Implantable cardioverter-defibrillators were investigated for their impact on mortality in 228 consecutive heart transplant candidates on the waiting list for transplantation (207 patients without and 21 with implantable cardioverter-defibrillator therapy). The mortality rate in 207 patients without implantable cardioverter-defibrillator therapy was 23.2% and in 21 patients with implantable cardioverter-defibrillator therapy was 4.7%. In a Cox proportional hazards model for all 228 study patients (mortality while on the waiting list: 21.5%; transplantation rate: 54.8%), the absence of an implantable cardioverter-defibrillator was only a marginally significant predictor of mortality (p = 0.079). However, the absence of an implantable cardioverter-defibrillator was a powerful predictor of mortality for a subgroup of 134 patients with high-grade ventricular arrhythmias on Holter electrocardiography (mortality while on the waiting list: 26.1%; transplantation rate: 54.5%; p = 0.022) and for a subgroup of 58 survivors of sudden cardiac death (mortality while on the waiting list: 22.4%; transplantation rate: 56.9%; p = 0.018). Implantable cardioverter-defibrillator therapy can be strongly recommended in transplant candidates with a history of sudden cardiac death. Recommendations for an expanded, prophylactic use of implantable cardioverter-defibrillator therapy in heart transplant candidates cannot be given.

ICD therapy in survivors of sudden cardiac death awaiting heart transplantation

The impact of implantable cardioverter defibrillator (ICD) therapy on survival of heart transplant candidates is of major socioeconomic and ethical interest. However, efficacy is even uncertain for patients at highest risk of tachyarrhythmic death on the waiting list. We studied 60 selected heart transplant candidates (mean age, 55.8 years; mean left ventricular ejection fraction, 0.15; functional class III and IV) with a history of successful resuscitation by external electric defibrillation for spontaneous, syncopal ventricular tachyarrhythmia during the study period from March 1992 through September 1994. At the time of registration for transplantation, 30 patients had ICD devices implanted, whereas 30 patients lacked ICD therapy for various nonmedical reasons. Both therapy groups were comparable in clinical and hemodynamic characteristics as well as in intention to transplant (median waiting time to transplantation, 5.7 and 6 months, respectively; not significant by log-rank method). Survival on the waiting list was significantly improved by ICD therapy; only 1 of the 30 ICD patients (19 transplanted) but 7 of the 30 non-ICD patients (14 transplanted) died on the waiting list (p < 0.05 by log-rank method). Implantable cardioverter defibrillator therapy did not affect survival after transplantation as compared with non-ICD patients (not significant by log-rank method). During the waiting time, 26 of the ICD patients (87%) experienced adequate ICD discharges, and 12 of the non-ICD patients were treated successfully by external electric defibrillation (40%).(ABSTRACT TRUNCATED AT 250 WORDS)

Serial recording of sensory evoked potentials: a noninvasive prognostic indicator in fulminant liver failure

Sensory evoked potentials are markedly changed in patients with fulminant liver failure. It is unknown, however, whether serial recordings of sensory evoked potentials provide useful prognostic informations for patient management in fulminant liver failure. Ninety recordings of bilateral median nerve-stimulated short- and long-latency sensory evoked potentials were performed in 25 patients with fulminant liver failure (9 patients spontaneously recovered and survived, 8 patients were referred to emergency liver transplantation and 8 patients died). In all nine survivors the cortical long-latency sensory evoked potential N70 peak was constantly detectable between 74 and 162 ms. In all eight patients who subsequently underwent liver transplantation and in seven of eight patients who died, loss of the N70 peak developed during the course of fulminant liver failure. In 4 of 15 patients who were selected for liver transplantation according to the King's College criteria, the N70 peak was constantly detectable. All four transplantation candidates spontaneously recovered and survived without transplantation. In contrast, eight patients never did fulfill the criteria for liver transplantation. Five of them with constantly detectable N70 peak recovered spontaneously. However, in the remaining three patients loss of the N70 peak developed, and they ultimately died. The probability of correct outcome prediction by sensory evoked potentials is superior to that based on clinical criteria alone (0.96 vs. 0.72). Therefore serial recording of sensory evoked potentials may help identify (a) a subgroup among liver transplantation candidates who may spontaneously recover without transplantation and (b) a subgroup of patients with severe brain dysfunction who should undergo early liver transplantation even though they do not fulfill King's College criteria.

Cognitive brain function in non-demented patients with low-grade and high-grade carotid artery stenosis

Atherosclerotic stenosis of the carotid arteries decreases cerebral flow volume and perfusion, and may result in brain dysfunction. We studied the relationship between the degree of carotid artery stenosis and cognitive brain function in non-demented patients. Cognitive brain function was assessed in 76 patients with carotid artery stenosis (38 patients with low-grade stenosis of 50% or less, and 38 patients with high-grade stenosis of 75% or more) by recording of cognitive P300 auditory evoked potentials and trailmaking test. Results were compared to 70 age-matched healthy subjects. The P300 peak latency was prolonged in patients with high-grade carotid artery stenosis as compared to patients with low-grade stenosis (403 vs. 371 ms, P < 0.01, vertex; 400 vs. 370 ms, P < 0.01, frontal; means). Analysis of variance revealed that the degree of carotid artery stenosis is an independent predictor of prolonged P300 peak latency (P = 0.0001). P300 amplitude (12 vs. 15 microV, vertex; 13 vs. 15 microV, frontal, NS) and trailmaking test (60 vs. 54 s; NS) tended to be worse in the high-grade stenosis group. There was no difference in cognitive brain function between patients with low-grade stenosis and age-matched healthy subjects. Confirmed on sensitive cognitive P300 measurements, we conclude that (a) cognitive brain function is impaired in non-demented patients with high-grade carotid artery stenosis but unaffected in low-grade stenosis; and (b) cognitive brain dysfunction is directly related to the degree of carotid artery stenosis.

Acute renal failure in the elderly 1975-1990

Two hundred and forty-two elderly patients (> 65 years) with acute renal failure (ARF) treated at a predominantly medical intensive care unit between 1975 and 1990 were retrospectively analyzed for underlying diseases, severity of disease (as evaluated by the rate of ventilated patients, septicemia and APACHE II score, respectively), causes of ARF, acute and chronic risk factors for the development of ARF, complications during treatment and outcome. Overall mortality was 61%; 28 patients (12%) died in spite of resolution of ARF so actually, 49% of the patients died in ARF. Outcome was comparable to other age groups with overall mortality being 57% in patients < 18 years and 59% in those 19-65 years. Moreover, within the group of elderlies mortality did not increase with age and was 60% in those aged 65-68 and 54% in those aged > 80 years, respectively. The need for renal replacement therapy, plasma creatinine > 6 mg/dl, anuria, BUN > 120 mg/dl, ventilator dependency and the presence of septicemia all negatively affected outcome. During the years 1975 to 1990 mortality decreased from > 70% to < 50% (p < 0.02). This improvement of survival was seen in spite of an increase in the severity of disease (1975-1982: 20% ventilated patients, 24% with septicemia, 1983-1990 51% and 40%, respectively, p < 0.01). We conclude that age per se is not an important determinant of survival in patients with ARF and that prognosis has improved considerably during the last 15 years and this was seen in spite of an increase in the severity of disease. It is not justified to withhold therapy in elderly patients acquiring ARF.