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P G Metnitz

Publications and source records attributed to P G Metnitz.

16 recordsLinked to original sources
PubMed2001

Evaluation of the logistic organ dysfunction system for the assessment of organ dysfunction and mortality in critically ill patients.

OBJECTIVES: To evaluate the performance of the logistic organ dysfunction (LOD) system for the assessment of morbidity and mortality in multiple organ dysfunction/failure (MOD/F) in an independent database and to evaluate the use of sequential LOD measurements for the prediction of outcome. DESIGN AND SETTING: Prospective, multicentric cohort study in 13 adult medical, surgical, and mixed intensive care units (ICUs) in Austria. PATIENTS: A total of 2,893 consecutive admissions to the ICUs. MEASUREMENTS AND MAIN RESULTS: Patient vital status at ICU and hospital discharge was recorded. Univariate analysis showed that the LOD was able to distinguish between survivors and nonsurvivors (2 vs. 6 median score). Within organ systems, higher levels of the severity of organ dysfunction were consistently associated with higher mortality. For the prediction of hospital mortality, the original prognostic LOD model did not perform well in our patients, as indicated by the goodness-of-fit C statistic. Using multiple logistic regression we developed a prognostic model with a satisfactory fit in our patients. The integration of further measurements during the ICU stay increased discrimination but not calibration. CONCLUSIONS: The LOD system is well correlated well with the numbers and levels of organ dysfunctions and discriminates well between survivors and nonsurvivors. It can thus be used to quantify the baseline severity of organ dysfunction. Moreover, after customization of the predictive equation the LOD predicted hospital mortality in our patients with high precision. It thus provides a combined measure of morbidity and mortality for critically ill patients with MOD/F.

Aged↗
PubMed2000

Intrathoracic fluid volumes and pulmonary function during orthotopic liver transplantation.

BACKGROUND: Impaired pulmonary function is a frequent finding in patients undergoing orthotopic liver transplantation (OLT). Experimental data suggest an essential contribution of splanchnic ischemia and reperfusion as a result of intraoperative volume shifts, i.e., the accumulation of extravascular lung water (EVLW). Increases of intrathoracic blood volume (ITBV) and pulmonary blood volume (PBV) might additionally influence pulmonary capillary fluid filtration. The main objective of this study was to determine the intrathoracic volume changes during OLT and to test whether there were any relationships between intra- and extravascular volume shifts and pulmonary function, as determined by the calculation of venous admixture (QS/QT) and alveolar-arterial oxygen gradient (AaDO2). METHODS: Twenty-five patients undergoing OLT were studied. Using the transpulmonary double indicator dilution method, ITBV, PBV, and EVLW were determined from the mean transit times and exponential decay times of the indocyanine green and the thermal indicator curves recorded simultaneously with a fiberoptic catheter in the descending aorta. Recordings were made after induction of anesthesia, at the end of the anhepatic stage, immediately after reperfusion, and 1 and 4 h postoperatively. RESULTS: Significant increases in QS/QT related to changes of ITBV were observed after reperfusion. Only a minor impact on AaDO2 was perceived. EVLW remained constant during the study period. CONCLUSIONS: Postreperfusion increases of ITBV influence pulmonary function, as demonstrated by the increase in QS/QT. However, they need not be associated with greater EVLW levels, and impact on oxygenation is less severe than assumed. Hence, sufficient mechanisms protecting oxygenation and stalling increased EVLW seem to be present during uncomplicated human OLT.

Adult↗
PubMed2000

Ratios of observed to expected mortality are affected by differences in case mix and quality of care.

OBJECTIVES: To validate SAPS II-AM, a recently customized version of the Simplified Acute Physiology Score II (SAPS II) in a larger cohort of Austrian intensive care patients and to evaluate the effect of the customization process on the ratio of observed to expected mortality. DESIGN: Prospective, multicentric cohort study. PATIENTS AND SETTING: A total of 2,901 patients consecutively admitted to 13 adult medical, surgical, and mixed intensive care units (ICUs) in Austria. MEASUREMENTS AND RESULTS: After the database was divided randomly into a development sample (n = 1,450) and a validation sample (n = 1,451), logistic regression was used to develop a new model (SAPS II-AM2). The original SAPS II, the SAPS IIAM, and the newly developed SAPS II-AM2 were then compared by means of calibration, discrimination and O/E ratios. Differences in O/E ratios before and after customization (deltaO/E) were calculated. The Hosmer-Lemeshow goodness-of-fit H and C statistics revealed poor calibration of the original SAPS II on the database. The new model, SAPS II-AM2, performed better than the SAPS II-AM and excellent in the validation data set. However, mean O/E ratios varied widely among diagnostic categories (range 0.55-1.05 for the SAPS II). Moreover, the deltaO/E of the 13 ICUs ranged from -3.6 % to +25 %. CONCLUSIONS: Today's severity scoring systems, such as the SAPS II, are limited by not measuring (and adjusting for) a profound part of what constitutes case mix. Changes in the distribution of patient characteristics (known and unknown) therefore affect prognostic accuracy. First-level customization was not able to solve all these problems. Using O/E ratios for quality of care comparisons one must therefore be critical when using these data and should search for possible confounding factors. In the case of unsatisfactory calibration, customized severity of illness models may be useful as an adjunct for quality control.

APACHE↗
PubMed1999

Antioxidant status in patients with acute respiratory distress syndrome.

OBJECTIVES: Reactive oxygen species (ROS) have been implicated in the pathophysiology of ARDS. We investigated the pattern of antioxidants in plasma and ROS production by neutrophils in patients with ARDS over 6 days. DESIGN: Observational study. Blood samples were taken when the diagnosis was made (D0) and after 3 (D3) and 6 days (D6) during therapy. SETTING: Intensive care units at a University Hospital. PATIENTS: Eight patients with ARDS were investigated, 17 healthy volunteers served as controls. MEASUREMENTS AND RESULTS: Plasma levels of ascorbate, alpha-tocopherol, retinol, beta-carotene, selenium and lipid peroxidation products (MDA) were determined and the activities of the antioxidative enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione-peroxidase (GSH-PX) in erythrocytes were measured. In addition, ROS production (superoxide anion and hydrogen peroxide) in activated neutrophils was assessed. Plasma levels of alpha-tocopherol, ascorbate, beta-carotene and selenium were reduced from the onset of illness. MDA plasma levels were increased throughout the illness. ROS generation from neutrophils was normal on D0 and decreased to D6 in ARDS patients. CONCLUSION: The antioxidative system is severely compromised in patients with ARDS. Plasma levels of alpha-tocopherol, ascorbate, beta-carotene and selenium are decreased. Elevated MDA levels provide further evidence of massive oxidative stress. The routine replacement of micronutrients according to recommended daily allowances was inadequate to compensate for the increased requirements.

Adult↗
PubMed1999

Prognostic performance and customization of the SAPS II: results of a multicenter Austrian study. Simplified Acute Physiology Score.

OBJECTIVES: To evaluate the prognostic performance of the original Simplified Acute Physiology Score (SAPS) II in Austrian intensive care patients and to evaluate the impact of customization. DESIGN: Analysis of the database of a multicenter study. SETTING: Nine adult medical, surgical, and mixed intensive care units (ICUs) in Austria. PATIENTS: A total of 1733 patients consecutively admitted to the ICUs. MEASUREMENTS AND RESULTS: The database included admission data, SAPS II, length of stay, and hospital mortality. The Hosmer-Lemeshow goodness-of-fit test for the SAPS II showed a lack of uniformity of fit (H = 89.1, 10 df, p < 0.0001; C = 91.8, 10 df, p < 0.0001). Subgroup analysis showed good performance in patients with cardiovascular (medical and surgical) diseases as the primary reasons for admission. A new predictive equation was derived by means of the logistic regression. Goodness-of-fit was excellent for the customized model (SAPS IIAM) (H = 11.2, 9 df, p = 0.33, C = 11.6, 9 df, p = 0.24). The mean standardized mortality ratio (SMR) changed from 0.81 +/- 0.26 to 0.93 +/- 0.29 with customization. CONCLUSIONS: SAPS II was not well calibrated when applied to all patients. However, it performed well for patients with cardiovascular diseases as the primary reason for admission and may thus be applied to these patients. Standardized mortality ratios that are calculated from scoring systems without known calibration must be viewed with skepticism.

Austria↗
PubMed1999

Splanchnic circulation is maintained during passive hyperventilation in orthotopic liver recipients.

BACKGROUND: Mechanical hyperventilation is an established treatment to reduce brain edema and intracranial pressure in patients with encephalopathia caused by acute liver failure. Hyperventilation and ensuing hypocarbia may also affect central and systemic circulation and thereby influence graft performance in patients following orthotopic liver transplantation (OLT). METHODS: We measured the effects of normocapnia and hypocapnia on systemic hemodynamics, gastric tonometry, as a marker of splanchnic oxygenation, and the indocyanine green kinetic, as a global marker of graft function, in humans post OLT. RESULTS: Hyperventilation was performed to a PaCO2 of 4.2 +/- 0.4 kPa (31 +/- 3.4 mm Hg) for about 1 h in 14 liver transplant recipients. Systemic hemodynamics as well as indices of splanchnic oxygenation and indocyanine green kinetics remained statistically unchanged. CONCLUSION: We did not observe any statistically significant circulatory effects or changes in indocyanine green kinetics in liver transplant recipients in the immediate OLT postoperative period caused by short-term mechanical hyperventilation.

Blood Pressure↗
PubMed1999

Evaluation of an interdisciplinary data set for national intensive care unit assessment.

OBJECTIVES: To evaluate the ability of an interdisciplinary data set (recently defined by the Austrian Working Group for the Standardization of a Documentation System for Intensive Care [ASDI]) to assess intensive care units (ICUs) by means of the Simplified Acute Physiology Score II (SAPS II) for the severity of illness and the simplified Therapeutic Intervention Scoring System (TISS-28) for the level of provided care. DESIGN: A prospective, multicentric study. SETTING: Nine adult medical, surgical, and mixed ICUs in Austria. PATIENTS: A total of 1234 patients consecutively admitted to the ICUs. INTERVENTIONS: Collection of data for the ASDI data set. MEASUREMENTS AND MAIN RESULTS: The overall mean SAPS II score was 33.1+/-2.1 points. SAPS II overestimated hospital mortality by predicting mortality of 22.2%+/-2.9%, whereas observed mortality was only 16.8%+/-2.2%. The Hosmer-Lemeshow goodness-of-fit test for SAPS II scores showed lacking uniformity of fit (H = 53.78, 8 degrees of freedom; p < .0001). TISS-28 scores were recorded on 8616 days (30.6+/-1.5 points). TISS-28 scores were higher in nonsurvivors than in survivors (30.4+/-0.9 vs. 25.7+/-0.4, respectively; p < .05). No significant correlation between mean TISS-28 per patient per unit on the day of admission and mean predicted hospital mortality (r2 = .23; p < .54) or standardized mortality ratio per unit (r2 = -.22; p < .56) was found. CONCLUSIONS: Implementation of an interdisciplinary data set for ICUs provided data with which to evaluate performance in terms of severity of illness and provided care. The SAPS II did not accurately predict outcomes in Austrian ICUs and must, therefore, be customized for this population. A combination of indicators for both severity of illness and amount of provided care is necessary to evaluate ICU performance. Further data acquisition is needed to customize the SAPS II and to validate the TISS-28.

APACHE↗
PubMed1997

[Definition and evaluation of a documentation standard for intensive care medicine: the ASDI(Working Group for Standardization of a documentation system for Intensive care medicine) pilot project].

OBJECTIVES: A comparison of data from different intensive care units (ICUs) needs standardized documentation. In this study the ASDI documentation standard for intensive care was tested in clinical practice. Goal of the study was to evaluate parameters and functionality required for a national, interdisciplinary documentation system for intensive care. DESIGN: 13 ICUs participated in a 4-week trial using the provided program for documentation of all admitted patients during the observation period. In addition, a questionnaire was distributed to the unit coordinators. RESULTS: 376 patients were documented in 1591 patient days. Valid SAPS II scores were found in only 29% of the discharged patients (39.1 +/- 15.5 points). Time needed for data entry exceeded preset limits (ten minutes per patient and day) in 38% of the cases. All participants affirmed the necessity of a documentation standard for intensive care, giving quality control and cost analysis as the most important reasons. CONCLUSION: The ASDI data set fitted existing needs very closely. Only 7 out of 122 parameters (5.7%) were found to be superfluous and thus removed. Measures to reduce documentation effort to the default limits were a) a new, date orientated concept for manual recording, b) rede-sign of the user interface with new, user friendly data entry possibilities, and c) the integration of statistical analysis and reports in the documentation system. The revised data set represents a broad-based consensus, which seems to be well-suited as foundation for the national quality assurance program.

Adolescent↗
PubMed1995

Patient data management systems in intensive care--the situation in Europe.

OBJECTIVE: Computerized Patient Data Management Systems (PDMS) have been developed for handling the enormous increase in data collection in ICUs. This study tries to evaluate the functionality of such systems installed in Europe. DESIGN: Criteria reflecting usefulness and practicality formed the basis of a questionnaire to be answered accurately by the vendors. We then examined functions provided and their implementation in European ICUs. Next, an "Information Delivery Test" evaluated variations in performance, taking questions arising from daily routine work and measured time of information delivery. SETTING: ICUs located in Vienna (Austria), Antwerp (Belgium), Dortmund (Germany), Kuopio (Finland). PARTICIPANTS: 5 PDMS were selected on the basis of our inclusion criteria: commercial availability with at least one installation in Europe, bedside-based design, realization of international standards and a prescribed minimum of functionality. RESULTS: The "Table of Functions" shows an overview of functions and their implementation. "System analyses" indicates predominant differences in properties and functions found between the systems. Results of the "Information Delivery Tests" are shown in the graphic charts. CONCLUSIONS: Systems with graphical data presentation have advantages over systems presenting data mainly in numerical format. Time has come to form a medical establishment powerful enough to set standards and thus communicate with industrial partners as well as with hospital management responsible for planning, purchasing and implementing PDMS. Overall, communication between clinicians, nurses, computer scientists and PDMS vendors must be enhanced to achieve the common goal: useful and practical data management systems at ICUs.

Database Management Systems↗
PubMed1995

Computer assisted data analysis in intensive care: the ICDEV project--development of a scientific database system for intensive care (Intensive Care Data Evaluation Project).

INTRODUCTION: Patient Data Management Systems (PDMS) for ICUs collect, present and store clinical data. Various intentions make analysis of those digitally stored data desirable, such as quality control or scientific purposes. The aim of the Intensive Care Data Evaluation project (ICDEV), was to provide a database tool for the analysis of data recorded at various ICUs at the University Clinics of Vienna. SETTINGS: General Hospital of Vienna, with two different PDMSs used: CareVue 9000 (Hewlett Packard, Andover, USA) at two ICUs (one medical ICU and one neonatal ICU) and PICIS Chart+ (PICIS, Paris, France) at one Cardiothoracic ICU. CONCEPT AND METHODS: Clinically oriented analysis of the data collected in a PDMS at an ICU was the beginning of the development. After defining the database structure we established a client-server based database system under Microsoft Windows NI and developed a user friendly data quering application using Microsoft Visual C++ and Visual Basic; RESULTS: ICDEV was successfully installed at three different ICUs, adjustment to the different PDMS configurations were done within a few days. The database structure developed by us enables a powerful query concept representing an 'EXPERT QUESTION COMPILER' which may help to answer almost any clinical questions. Several program modules facilitate queries at the patient, group and unit level. Results from ICDEV-queries are automatically transferred to Microsoft Excel for display (in form of configurable tables and graphs) and further processing. CONCLUSIONS: The ICDEV concept is configurable for adjustment to different intensive care information systems and can be used to support computerized quality control. However, as long as there exists no sufficient artifact recognition or data validation software for automatically recorded patient data, the reliability of these data and their usage for computer assisted quality control remain unclear and should be further studied.

Austria↗