Hekmat et al reported the Cardiac Surgery Score (CASUS) for evaluating cardiac surgery patients in the intensive care unit (ICU) following surgery. The authors are from the University of Cologne in Germany
Patient selection: cardiac surgery patient in the ICU
Parameters:
(1) PaO2 to FIO2 ratio
(2) pressure-adjusted heart rate (PAR)
(3) serum creatinine in mg/dL
(4) serum total bilirubin in mg/dL
(5) lactic acid in mmol/L
(6) platelet count in 10^3 per microliter
(7) neurologic status
(8) intra-aortic balloon pump (IABP)
(9) ventricular assist device (VAD)
(10) renal replacement therapy (continuous venovenous hemofiltration, dialysis)
PaO2 to FIO2 ratio =
= (PaO2 in mm Hg) / (FIO2 from 0.21 to 1.0)
platelet count in 10^3 per microliter =
= (platelet count per microliter) / 1000
PAR =
= (heart rate) * (central venous or right atrial pressure in mm) / (mean arterial pressure in mm)
mean arterial pressure =
= ((systolic blood pressure) + (2 * (diastolic pressure))) / 3
Parameter |
Finding |
Points |
PaO2 to FIO2 ratio |
extubated |
0 |
|
> 250 |
1 |
|
151 to 250 |
2 |
|
75 to 150 |
3 |
|
< 75 |
4 |
pressure adjusted heart rate |
< 10.1 |
0 |
|
10.1 to 15.0 |
1 |
|
15.1 to 20.0 |
2 |
|
20.1 to 30.0 |
3 |
|
> 30.0 |
4 |
serum creatinine |
< 1.2 mg/dL |
0 |
|
1.2 to 2.2 mg/dL |
1 |
|
2.3 to 4.0 mg/dL |
2 |
|
4.1 to 5.5 mg/dL |
3 |
|
> 5.5 mg/dL |
4 |
serum total bilirubin |
< 1.2 mg/dL |
0 |
|
1.2 to 3.5 mg/dL |
1 |
|
3.6 to 7.0 mg/dL |
2 |
|
7.1 to 14.0 mg/dL |
3 |
|
> 14.0 mg/dL |
4 |
lactic acid |
< 2.1 mmol/L |
0 |
|
2.1 to 4.0 mmol/L |
1 |
|
4.1 to 8.0 mmol/L |
2 |
|
8.1 to 12.0 mmol/L |
3 |
|
> 12.0 mmol/L |
4 |
platelet count in 10^3 per µL |
> 120 |
0 |
|
81 to 120 |
1 |
|
51 to 80 |
2 |
|
21 to 50 |
3 |
|
< 21 |
4 |
neurologic status |
normal |
0 |
|
confused in conversation |
2 |
|
sedated |
3 |
|
diffuse neuropathy |
4 |
intra-aortic balloon pump |
no |
0 |
|
yes |
4 |
ventricular assist device |
no |
0 |
|
yes |
4 |
renal replacement therapy |
no |
0 |
|
yes |
4 |
where:
• The application of neurologic status may have to be modified in use. Coma would probably be scored as diffuse neuropathy and depressed mental status as sedation.
CASUS =
= SUM(points for all 10 parameters)
delta CASUS at 48 hours =
= (CASUS at 48 hours) – (initial CASUS)
delta CASUS at 96 hours =
= (CASUS at 96 hours) – (initial CASUS)
Interpretation:
• minimum score: 0
• maximum score: 40
• The higher the score the more serious the patient’s condition.
• Higher delta CASUS values are associated with increased mortality.
Performance:
• The area under the ROC curve varied from 0.85 to 0.91 over period from operative day to postoperative day 5 (Hekmat et al).
Specialty: Critical Care, Emergency Medicine, Surgery, general, Cardiology