Renal Function After Cardiac Surgery: Adverse Effect of Furosemide

Figures & data

Table 1. Intraoperative variables

Type of surgery
Coronary by-pass	36
Valve replacement	10
By-pass and valve replacement	2
Other	2
CPB timea (min)	77.7±34
Aortic cross clamping time (min)	42.9±19.8
Furosemide dose (mg)	101.5±28
Mannitol dose (g)	61.5±21.3
Hemodilution index	18±4.6
Autotransfusion volume (mL)	591.7±570

^aCardiopulmonary by-pass time.

Table 2. Values of MAPa during surgery

	Intraoperatory MAP	Minimum MAP during surgery	Early 12 h postoperatory time	Late 12 h postoperatory time
MAP (mmHg)	53.4 ± 9.8	41.1 ± 12.5	77.3 ± 57	74.7 ± 53.5
Range	33–77	0–62	57–99	53–99

^aMean arterial pressure.

Figure 1. Serum creatinine (S_Cr) (mg/dl), and creatinine clearance (C_Cr) (mL/min) through the observation period.

Figure 2. Diuresis along the study period (ml/hr).

Figure 3. Evolution of serum creatinine (S_Cr) along the observation period in patients with S_Cr at T4 less or equal to 2 mg/dl (Group I), or above 2 mg/dl (Group II). It is also shown FENa at the end of the study (T4).

Figure 4. Evolution of serum creatinine (S_Cr) along the observation period in patients with S_Cr at T4 less or equal to 1.5 mg/dL, or above 1.5 mg/dL. It is also shown FENa at the end of the study (T4).

Table 3. Results of univariate analysis. Only baseline S_Cr, FENa at T4, frusemide dose and hemodilution were statistically associated with groups

	Group I	Group II	p value
Baseline SCr (mg/dl)	1.01±0.23	1.26±0.19	0.030
FENa T4	0.99±0.8	2.2±2.1	0.040
Frusemide dose (mg)	96.5±20	140±49	0.001
Hemodilution index	17.3±4.3	22.8±3.2	0.004

Table 4. In multivariate analysis, only baseline S_cr and furosemide dose reached statistical significance

Variable	β	t	P
Baseline Cr	0.707	6.167	0.000
Furosemide dose	0.474	4.927	0.000

Figure 5. Multiple regression model shows association of furosemide dose and baseline creatininemia with S_Cr at 24 h. There is a high correlation between observed and calculated S_Cr at 24 h (r = 0.836).