Zusammenfassung
Hintergrund
Das Ziel dieser prospektiven Studie war festzustellen, ob präoperative Risikoscores die Gesamtkosten in der Herzchirurgie vorhersagen können.
Methoden
Zwischen dem 1. Oktober und 31. Dezember 2003 wurden alle konsekutiven erwachsenen Patienten, die sich einem herzchirurgischen Eingriff mit Herz-Lungenmaschine unterzogen, mittels sieben verschiedener Risikostratifizierungsmodelle klassifiziert: EuroSCORE, Cleveland, Parsonnet, Ontario, French, Pons und CABDEAL. Die Gesamtkosten des Krankenhauses wurden für jeden Patienten täglich prospektiv berechnet. In die Analyse wurden Kosten der präoperativen Diagnostik, der operativen Prozedur, der Verbrauchsmaterialien, der Medikamente, der Blutprodukte, der Personalkosten und die Fixkosten des Krankenhauses nach Angaben des Kalkulationshandbuches Version 2,0 mit eingerechnet. Die Korrelation zwischen den erreichten Scorepunkten und den entstandenen Kosten erfolgte mit den Korrelationskoeffizienten nach Spearman. Die Erlöse aller Patienten wurden mit ihren Zu- und Abschlägen für das Jahr 2003 ermittelt.
Ergebnisse
Insgesamt wurden 252 erwachsene Patienten mit Herz-Lungenmaschine operiert. Davon erhielten 175 Patienten eine Bypassoperation, 39 Patienten eine Klappenoperation, 21 Patienten eine kombinierte Bypass- und Klappenoperation, 13 Patienten eine Operation an der thorakalen Aorta. Außerdem wurden 2 Patienten wegen eines Myxoms, 1 Patient wegen eines Vorhofseptumdefekts und 1 Patient wegen einer fulminanten Lungenembolie operiert. Das mittlere Alter der Patienten lag bei 66,0±11,4 Jahre, 29,4% der Patienten waren weiblich. Die Intensivliegedauer lag bei 3,3±6,3 Tagen, und die 30-Tageletalität lag bei 6,7%. Die Korrelationskoeffizienten zwischen den 7 Risikomodellen und den Klinikkosten war mit einem r<0,33 (p=0,0001) sehr niedrig. Eine deutliche Korrelation r=0,94 (p=0,0001) konnte jedoch zwischen der Intensivverweildauer und Kosten ermittelt werden.
Schlussfolgerung
Die Krankenhauskosten können mit der Länge des Intensivaufenthaltes gut prognostiziert werden. Eine Kostenprognose war jedoch mit keinem Risikomodell möglich.
Summary
Background
The aim of this prospective study was to determine if commonly used risk stratification models can predict total hospital costs in cardiac surgical patients.
Methods
Between October 1st and December 31st 2003, all consecutive adult patients undergoing cardiac surgery on CPB at our institution were classified using seven risk stratification scoring systems: EuroSCORE, Cleveland, Parsonnet, Ontario, French, Pons, and CABDEAL. Total hospital costs for each patient were calculated on a daily basis including preoperative diagnostic tests, operating room costs, disposable materials, drugs, blood components, costs for personnel, and hospital fixed-costs. Linear regression analysis was used to determine the correlation between costs and the seven risk stratifications models as well as length of stay (LOS) on ICU. The Spearman correlation coefficient was calculated from the regression line, and an analysis of residuals was performed to determine the quality of the regression.
Results
A total of 252 patients were operated for CABG (n=175), valve (n=39), CABG plus valve (n=21), thoracic aorta (n=13) and miscellaneous (2 myxoma, 1 ASD, 1 pulmonary embolism). Mean age of the patients was 66.0±11.4 years, 29.4% were female. LOS on ICU was 3.3±6.3 days and the 30-day mortality rate was 6.7%. Spearman correlation between the seven risk stratification models and hospital costs was below r=0.32 (p=0.0001), but was r=0.94 (p=0.0001) between ICU LOS and costs.
Conclusions
Total hospital costs can be identified by length of ICU stay. None of the common risk stratification models accurately predicted total hospital costs in cardiac surgical patients.
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Presented at the 34th Annual Meeting of the German Society for Thoracic and Cardiovascular Surgery, 13–16 February 2005, Hamburg, Germany
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Hekmat, K., Raabe, A., Kroener, A. et al. Risk stratification models fail to predict hospital costs of cardiac surgery patients. ZS Kardiologie 94, 748–753 (2005). https://doi.org/10.1007/s00392-005-0300-8
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DOI: https://doi.org/10.1007/s00392-005-0300-8