Comparison between Sequential Organ Failure Assessment Score (SOFA) and Cardiac Surgery Score (CASUS) for Mortality Prediction after Cardiac Surgery

Abstract

Background Our purpose was to evaluate and compare the accuracy of the “Sequential Organ Failure Assessment” score (SOFA) and the “Cardiac Surgery Score” (CASUS) for the prediction of mortality after cardiac surgery.

Methods Between January 1, 2007 and December 31, 2008 we prospectively included all consecutive adult patients admitted to our intensive care unit (ICU) after cardiac surgery. Both scoring systems were calculated daily from the 1st day in the ICU (day of operation) until the 7th ICU day. We evaluated the ICU mortality prediction of both models using calibration and discrimination statistics.

Results 2801 patients (29.6% females) were included. Mean age was 66.9 ± 10.7 years. Intensive care unit mortality was 5.2%. The calibration of the “Sequential Organ Failure Assessment Score” and “Cardiac Surgery Score” was reliable for all days (p ≥ 0.05). CASUS was more accurate in predicting survival and mortality compared to SOFA for all days, as evidenced by the larger areas under the Receiver Operating Characteristic curves.

Conclusions Both CASUS and SOFA are reliable mortality prediction tools after cardiac surgery. However, CASUS was more accurate in predicting the individual patient's risk of mortality. Thus, use of the CASUS in cardiac surgery intensive care units is recommended.

Key words

outcomes (includes mortality morbidity) - intensive care - scoring system - cardiac surgery - mortality prediction

• References

• 1 Knaus W, Draper E, Wagner D, Zimmerman J. APACHE II a severity of disease classification system. Crit Care Med 1985; 13: 818-829
• 2 Marshall JC, Cook DJ, Christou NV, Bernard GR, Sprung CL, Sibbald WJ. Multiple organ dysfunction score: a reliable descriptor of a complex clinical outcome. Crit Care Med 1995; 23: 1638-1652
• 3 Ceriani R, Mazzoni M, Bortone F , et al. Application of the sequential organ failure assessment score to cardiac surgical patients. Chest 2003; 123: 1229-1239
• 4 Pätilä T, Kukkonen S, Vento A, Pettilä V, Suojaranta-Ylinen R. Relation of the sequential organ failure assessment score to morbidity and mortality after cardiac surgery. Ann Thorac Surg 2006; 82: 2072-2079
• 5 Hekmat K, Kroener A, Stuetzer H , et al. Daily assessment of organ dysfunction and survival in intensive care unit cardiac surgical patients. Ann Thorac Surg 2005; 79: 1555-1562
• 6 Vincent JL, Moreno R, Takala J , et al. The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. On behalf of the working group on sepsis-related problems of the European Society of Intensive Care Medicine. Intensive Care Med 1996; 22: 707-710
• 7 Vincent JL, Ferreira F, Moreno R. Scoring systems for assessing organ dysfunction and survival. Crit Care Clin 2000; 16: 353-366
• 8 Badreldin AM, Kroener A, Heldwein MB , et al. Prognostic value of daily Cardiac Surgery Score (CASUS) and its derivatives in cardiac surgery patients. Thorac Cardiovasc Surg 2010; 58: 392-397
• 9 Sakr Y, Krauss C, Amaral A , et al. Comparison of the performance of SAPS II, SAPS3, APACHE II, and their customized prognostic models in a surgical intensive care unit. Br J Anaesth 2008; 101: 798-803
• 10 Vincent JL, de Mendonça A, Cantraine F , et al. Use of the SOFA score to assess the incidence of organ dysfunction/failure in intensive care units: results of a multicenter, prospective study. Working group on “sepsis-related problems” of the European Society of Intensive Care Medicine. Crit Care Med 1998; 26: 1793-1800
• 11 Hekmat K, Doerr F, Kroener A , et al. Prediction of mortality in intensive care unit cardiac surgical patients. Eur J Cardiothorac Surg 2010; 38: 104-109
• 12 Rady MY, Ryan T. Perioperative predictors of extubation failure and the effect on clinical outcome after cardiac surgery. Crit Care Med 1999; 27: 340-347
• 13 Kollef MH, Wragge T, Pasque C. Determinants of mortality and multiorgan dysfunction in cardiac surgery patients requiring prolonged mechanical ventilation. Chest 1995; 107: 1395-1401
• 14 Marshall JC, Cook DJ, Christou NV, Bernard GR, Sprung CL, Sibbald WJ. The multiple organ dysfunction (MOD) score: a reliable descriptor of a complex clinical outcome. Crit Care Med 1995; 23: 1638-1652
• 15 Cook R, Cook D, Tilley J , et al. Multiple organ dysfunction: baseline and serial component scores. Crit Care Med 2001; 29: 2046-2050
• 16 Higgins TL, Estafanous FG, Loop FD , et al. ICU admission score for predicting morbidity and mortality risk after coronary artery bypass grafting. Ann Thorac Surg 1997; 64: 1050-1058
• 17 Jansen TC, VAN Bommel J, Bakker J. Blood lactate monitoring in critically ill patients: a systematic health technology assessment. Crit Care Med 2009; 37: 2827-2839
• 18 Nichol AD, Egi M, Pettila V , et al. Relative hyperlactatemia and hospital mortality in critically ill patients: a retrospective multi-centre study. Crit Care 2010; 14 (1) R25