Table 4.

Comparisons of cardiac surgery associated acute kidney injury positive and negative cases statistically tested by unpaired t-test

Parameters	CSA-AKI positive (n=66)		CSA-AKI negative (n=68)		P
	Mean (SD)/n (%)#	95% CI of mean	Mean (SD)/n (%)#	95% CI of mean
Male#	32 (48.48)		28 (41.18)		0.4873
Female#	34 (51.52)		40 (58.82)		0.4873
Age (years)	39.66 (13.15)	36.43-42.90	36.35 (11.71)	33.51-39.19	0.1256
Weight (kg)	50.95 (7.81)	49.03-52.87	48.80 (8.66)	46.71-50.90	0.1349
Height (cm)	159.80 (7.90)	157.86-161.75	156.61 (8.70)	154.51-158.73	0.0284
eGFR (ml/min/1.73m2)	74.12 (22.57)	68.57-79.67	66.40 (18.49)	61.92-70.88	0.0319
Preoperative creatinine (mg %)	0.91 (0.22)	0.85-0.96	1.02 (0.22)	0.96-1.07	0.0047
Preoperative blood urea (mg %)	29.75 (14.70)	26.14-33.37	30.36 (17.66)	26.08-34.64	0.8286
CPB time (min)	103.71 (40.50)	93.74-113.68	89.30 (43.38)	78.79-99.82	0.0492
X-clamp (min)	79.62 (34.53)	71.12-88.11	66.76 (37.30)	57.72-75.80	0.0405
POD 1 urine output	1.15 (0.28)	1.08-1.28	1.25 (0.41)	1.15-1.35	0.1208
POD 2 urine output	1.17 (0.37)	1.08-1.27	1.21 (0.37)	1.12-1.30	0.5596
POD 3 urine output	1.21 (0.41)	1.11-1.31	1.20 (0.28)	1.14-1.27	0.9644
Serum creatinine (mg %)
POD 1	1.27 (0.37)	1.18-1.36	1.03 (0.24)	0.97-1.09	<0.0001
POD 2	1.36 (0.41)	1.26-1.47	1.00 (0.23)	0.95-1.06	<0.0001
POD 3	1.31 (0.47)	1.19-1.43	0.94 (0.23)	0.89-1.00	<0.0001
Blood urea (mg %)
POD 1	41.15 (14.59)	37.56-44.74	36.10 (13.17)	32.91-39.29	0.0374
POD 2	46.86 (14.99)	43.17-50.55	37.41 (13.71)	34.09-40.73	0.0002
POD 3	48.10 (16.42)	44.03-52.18	34.52 (13.76)	31.16-37.88	<0.0001

^#Fisher’s exact test, CSA-AKI: Cardiac surgery associated acute kidney injury, eGFR: Estimated glomerular filtration rate, SD: Standard deviation, CI: Confidence interval, CPB: Cardiopulmonary bypass, X-clamp: Aortic cross clamp, POD: Postoperative day