Early clinical outcomes of two regimens of prophylactic antibiotics in cardiac surgical patients with delayed sternal closure

Table 1 Baseline characteristics among the studied population

Variable	All patients, n = 53	Narrow-spectrum antibiotics, n = 12	Broad-spectrum antibiotics, n = 41	P value
Demographics
Age in yr	59.0 ± 12.1	60.0 ± 13.4	58.7 ± 11.8	0.366
BMI in kg/m2	26.7 ± 4.9 (N = 52)	25.7 ± 3.7 (n = 12)	26.7 ± 5.2 (n = 40)	0.227
Sex				0.175
Male	45/53 (85.0)	12	33
Female		0	8
Ethnicity				0.011
African	3/53 (5.7)	3	0
Arab	24/53 (45.3)	4	11
Asian from Indian subcontinent	20/53 (37.7)	3	17
Asia	4/53 (7.5)	0	4
Western	2/53 (3.8)	1	1
Smoking status				0.402
Non-smoker	23/51 (45.1)	3	20
Smoker	7/51 (13.7)	1	6
Ex-smoker	21/51 (41.2)	6	15
Comorbidities
Hypertension	28/51 (54.9)	4	24	0.086
Diabetes				0.305
Type II	16/53 (30.2)	4	12
Type I	7/53 (13.2)	0	7
COPD	2/52 (3.8)	0	2	1.00
CKD	8/53 (15.1)	1	7	0.665
On dialysis	2/53 (3.8)	0	2	1.00
PVD	2/53 (3.8)	0	2	1.00
Statin use	24/52 (46.2)	5	19	0.722
ECHO
LVEF as %	43.4 ± 16.9	45.8 ± 12.9	42.7 ± 18.0	0.578
LVEF groups				0.309
Good, > 50%	23/53 (43.4)	4	19
Moderate, 31%-50%	16/53 (30.2)	6	10
Poor, 21%-30%	10/53 (18.9)	2	8
Very poor, ≤ 20%	4/53 (7.5)	0	4

Data are total N/subset n (%) or mean ± standard deviation. BMI: Body mass index; CKD: Chronic kidney disease; COPD: Chronic obstructive pulmonary disease; ECHO: Echocardiography; LVEF: Left ventricular ejection fraction; PVD: Peripheral vascular disease.

Table 2 Laboratory test measurements among the studied population

Variable	All patients, n = 53	Narrow-spectrum antibiotics, n = 12	Broad-spectrum antibiotics, n = 41	P value
Creatinine in micromole/L	95.0 (72.0-110) (N = 51)	79.0 (ΔIQR 24.0) (n = 11)	95.0 (ΔIQR 46.0) (n = 40)	0.688
Highest creatinine in micromole/L	110 (85.0-175) (N = 51)	95.0 (ΔIQR 29.0) (n = 11)	107.5 (ΔIQR 106) (n = 40)	0.457
Bilirubin in micromole/L	9.0 (6.9-17.1) (N = 47)	8.6 (ΔIQR 26.5) (n = 10)	9.5 (ΔIQR 6.7) (n = 37)	0.755
SGPT in U/L	26.0 (18.0-40.0) (N = 47)	18.0 (ΔIQR 13.5) (n = 9)	25.5 (ΔIQR 22.3) (n = 38)	0.185
HbA1c as %	6.3 ± 1.6	5.9 ± 1.7	6.3 ± 1.5	0.243
Hb in mg/dL	12.9 ± 2.0 (N = 52)	13.2 ± 1.9 (n = 12)	12.7 ± 2.0 (n = 40)	0.239
WBC as 103/U	10.8 ± 5.2 (N = 49)	6.8 (ΔIQR 4.0) (n = 10)	8.8 (ΔIQR 3.0) (n = 39)	0.076

Data are median (IQR) or mean ± standard deviation. Hb: Hemoglobin; HbA1c: Glycated hemoglobin; IQR: Interquartile range; SGPT: Serum glutamate pyruvate transaminase; WBC: White blood cells.

Table 3 Peri-procedural findings

Variable	All patients	Narrow-spectrum antibiotics, n = 12	Broad-spectrum antibiotics, n = 41	P value
Procedure data				0.398
CABG	31/53 (58.5)	7	24
Valve replacement	11/53 (20.8)	4	7
Combined CABG/valve surgery	6/53 (11.3)	0	6
Aortic dissection	5/53 (9.4)	1	4
Epicardial wires	16/52 (30.8)	4	12	1.00
CPB in min	165 ± 75.3 (N = 50)	127.3 ± 67.9 (n = 10)	174.4 ± 74.9 (n = 40)	0.037
ACC in min	85.0 ± 45.7 (N = 41)	83.2 ± 50.5 (n = 9)	85.4 ± 45.1 (n = 32)	0.451
Open chest duration in d	3.0 (2.0-5.0)	2.0 (ΔIQR 2.0)	3.0 (ΔIQR 2.0)	0.146
Intraoperative transfusion	41/52 (78.8)	10	31	1.00
Postoperative transfusion	49/51 (96.1)	12	37	1.00
Blood loss in mL
At 6 h	700 (375-1350) (N = 45)	900 (ΔIQR 1050) (n = 11)	1050 (ΔIQR 1250) (n = 34)	0.864
At 12 h	1225 (500-2050) (N = 44)	1750 (ΔIQR 1000) (n = 11)	1575 (ΔIQR 2088) (n = 33)	0.881
At 24 h	1700 (775-2800) (N = 45)	1900 (ΔIQR 2500) (n = 11)	2175 (ΔIQR 3213) (n = 34)	0.8443
Total loss	2400 (1362-4700) (N = 44)	2050 (ΔIQR 4375) (n = 11)	3325 (ΔIQR 4300) (n = 33)	0.492
Support
Inotropes/vasopressors use
Agent(s) use	46/47 (97.9)	11	35	1.00
Number of agent(s) used				0.385
0	2/49 (4.1)	0	2
1	3/49 (6.1)	2	1
2	16/49 (32.7)	4	12
3	20/49 (40.8)	5	15
4	8/49 (16.3)	1	7
Number of agents used	2.6 ± 0.9 (N = 49)	2.4 ± 0.9 (n = 12)	2.6 ± 1.0 (n = 37)	0.24
IABP use	27/53 (50.9)	6	21	0.941
Defibrillation	13/53 (24.5)	3	10	1.00

Data are total N/subset n (%), median (IQR) or mean ± standard deviation. ACC: Aortic cross clamp; CABG: Coronary artery bypass grafting; CPB: Cardiopulmonary bypass; IABP: Intra-aortic balloon pump; IQR: Interquartile range.

Table 4 Clinical outcomes

Variable	All patients	Narrow-spectrum antibiotics, n = 12	Broad-spectrum antibiotics, n = 41	P value
New nosocomial infection	20/50 (40.0)	5	15	0.736
Time to sepsis/septic shock postoperatively in d	4.8 ± 2.6 (N = 50)	3.0 (ΔIQR 4.0) (n = 11)	3.5 (ΔIQR 2.0) (n = 39)	0.586
POAF	24/52 (46.2)	5	19	0.722
New ECG changes	39/51 (76.5)	9	30	1.00
Heart block	7/52 (13.5)	2	5	0.656
LV dysfunction	7/52 (13.5)	0	7	0.181
Postoperative MI	2/52 (3.8)	0	2	1.00
New postoperative stroke				0.576
Transient	3/50 (6.0)	0	3
Permanent	5/50 (10.0)	1	4
Duration of ventilation in h	70.0 (39.0-190)	50.0 (ΔIQR 113)	60.0 (ΔIQR 170)	0.047
LOS-ICU in d	8.0 (3.25-15.5) (N = 52)	5.0 (ΔIQR 5.0) (n = 12)	7.5 (ΔIQR 10.0) (n = 40)	0.008
LOS-hospital in d	27.0 (10.5-47.0) (N = 44)	19.0 (ΔIQR 21.0) (n = 11)	27.0 (ΔIQR 30.0) (n = 33)	0.031
Mortality	18/52 (34.6)	4	14	1.00
Readmission to ICU	5/51 (9.8)	1	4	1.00

Data are total N/subset n (%), median (IQR) or mean ± standard deviation. ECG: Electrocardiographic; ICU: Intensive care unit; IQR: Interquartile range; LOS: Length of stay; LV: Left ventricular; MI: Myocardial infarction; POAF: Postoperative atrial fibrillation.