Cardiac Surgery Score (CASUS) of Hekmat et al

 

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).