Validation of Cardiac Surgery Score (CASUS) in Postoperative Cardiac Patients

CASUS and APACHE II score in predicting mortality after coronary artery bypass grafting

Background

This study aims to compare Cardiac Surgery Score (CASUS) and the Acute Physiology and Chronic Health Evaluation (APACHE II) scoring systems for predicting mortality in patients undergoing isolated coronary artery bypass grafting.

Methods

Between January 2019 and March 2019, a total of 204 patients (166 males, 38 females; mean age: 60.5±0.7 years; range, 59.2 to 61.9 years) who underwent isolated coronary artery bypass grafting and were monitored at least for 24 h in the intensive care unit postoperatively were included. Pre-, intra-, and postoperative data were recorded. The CASUS and APACHE II scores were calculated using the most abnormal values for each variable during the first 24 h, postoperatively. Clinical outcomes were seven-day mortality and 30-day mortality, need for reintubation, readmission to the intensive care unit, length of intensive care unit stay and length of hospital stay.

Results

The 30-day overall mortality was 4.9% (n=10). The CASUS scores were significantly higher for patients developing mortality within 30 days postoperatively (p=0.030) and for patients needing reintubation (p=0.003). In the receiver operating characteristic curve analysis predicting seven-day mortality and prolonged intensive care unit stay, the area under curve was higher for CASUS scoring compared to APACHE II (0.90 vs. 0.72 and 0.82 vs. 0.76).

Conclusion

The CASUS may prove to be a more reliable scoring system than APACHE II for predicting mortality and morbidity in patients undergoing isolated coronary artery bypass grafting.

Analysis of the Performance of Daily Surgery Score (CASUS) in Patients with Mixed Racial Profile after Cardiac Surgery: A Single-Center Retrospective Study

OBJECTIVE

The aim was to look at the Cardiac Surgery Score (CASUS) assessment after cardiac surgery, and compare it with the intensive care unit (ICU) mortality and morbidity, in a racially diverse group of patients, in a single center.

DESIGN

Clinical retrospective study analyzing data from 319 patients over a 1-year duration.

SETTING

Cardiothoracic intensive care unit (CTICU) of a tertiary care center.

PARTICIPANTS

All patients who underwent cardiac surgery between January 1 and December 31, 2017.

INTERVENTIONS

Review of electronic patient records.

MEASUREMENTS AND RESULTS

Daily CASUS assessments (calculated on an online application and recorded on patient electronic records) were retrieved. The variables of CASUS used for the study were CASUS value on postoperative day 1 (POD1-CASUS), on death/discharge from CTICU (Dis-CASUS), mean of all CASUS values during CTICU stay (M-CASUS), and differential CASUS (Dif- CASUS) [CASUS POD 1 - CASUS on discharge]. The receiver operating characteristic (ROC) curve for the diagnostic level of POD 1-CASUS, indicating mortality, was calculated. A value of >6.5 for POD 1 CASUS had 80% sensitivity and 84% specificity, with area under the curve value 0.756 (95% confidence interval: 0.46 to 1). The mean values of POD1-CASUS (8.6 ± 6), M-CASUS (8.2 ± 5.2), and Dis-CASUS (7.8 ± 5.7) were significantly higher in cases of mortality, compared to the others. POD1-CASUS, M-CASUS, and Dis-CASUS were found to be statistically significantly elevated in patients with acute kidney injury (AKI) and postoperative stroke, and in those who were readmitted to the CTICU after initial discharge. Patients with POD1-CASUS ≥6.5 had a statistically significant association with mortality and postoperative morbidity (p < 0.05). Findings from multivariate logistic regression indicated that body mass index (BMI), ICU readmission, length of mechanical ventilation, and length of ICU stay remained associated significantly with POD1 CASUS ≥6.5.

CONCLUSION

This study found that CASUS on POD 1, mean values of CASUS during CTICU stay, and CASUS at death/discharge from CTICU predicted ICU mortality after cardiac surgery in this racially diverse group. The CASUS derivatives can be used to predict unfavorable outcomes after cardiac surgery. A POD1-CASUS value of 6.5 or more could signify mortality and postoperative morbidity.