Comparison of clinical and economic outcomes of two antibiotic prophylaxis regimens for sternal wound infection in high-risk patients following coronary artery bypass grafting surgery: a prospective randomised double-blind controlled trial.
OBJECTIVE
Prospective studies show a 10% incidence of sternal wound infection (SWI) after 90 days of follow-up, compared with infection rates of 5% reported by the National Nosocomial Infections Surveillance System after only 30 days of follow-up. This incidence increases 2-3 times in high-risk patients.


METHODS
Prospective randomised double-blind controlled clinical trial.


METHODS
Cardiothoracic centre, UK.


METHODS
Patients were eligible if they were undergoing median sternotomy for primary isolated coronary artery bypass grafting, with at least one internal thoracic artery used for coronary grafting and having one or more of the following three risk factors: (1) obesity, defined as body mass index 30 kg/m(2); (2) diabetes mellitus; or (3) bilateral internal thoracic artery grafts (ie, the use of the other internal thoracic artery).


METHODS
The study group received a single dose of gentamicin 2 mg/kg, rifampicin 600 mg and vancomycin 15 mg/kg, with three further doses of 7.5 mg/kg at 12-hour intervals. The control group received cefuroxime 1.5 g at induction and three further doses of 750 mg at 8-hour intervals.


METHODS
The primary end point was the incidence of SWI at 90 days. The secondary end point was the antibiotic and hospital costs.


RESULTS
During the study period, 486 patients underwent isolated coronary artery bypass grafting with a 30-day SWI of 7.6%. 186 high-risk patients were recruited and analysed: 87 in the study group and 99 in the control group. 90-day SWI was significantly reduced in 8 patients in the study group (9.2%; 95% CI 3.5% to 15.3%) compared with 25 patients in the control group (25.2%; 95% CI 19.5% to 39.4%; p = 0.004). The study group had a significantly lower cost of antibiotics (21.2% reduction--US$96/patient; p<0.001), and a significantly lower hospital cost (20.4% reduction in cost--US$3800/patient; p = 0.04).


CONCLUSIONS
Longer and broader-spectrum antibiotic prophylaxis significantly reduces the incidence of SWI in high-risk patients, with a significant economic benefit in costs of antibiotics as well as hospital costs.
Dhadwal
Kay
K
Harefield Hospital, Middlesex, UK.
Al-Ruzzeh
Sharif
S
Athanasiou
Thanos
T
Choudhury
Marina
M
Tekkis
Paris
P
Vuddamalay
Pynee
P
Lyster
Haifa
H
Amrani
Mohamed
M
George
Shane
S
D000328:Adult; D000367:Age Factors; D000368:Aged; D019072:Antibiotic Prophylaxis / Q000191:economics / Q000379:methods*; D001026:Coronary Artery Bypass; D004311:Double-Blind Method; D016527:Drug Costs / Q000706:statistics & numerical data; D004739:England; D005260:Female; D017721:Hospital Costs / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D013249:Sternum / Q000601:surgery*; D013530:Surgical Wound Infection / Q000191:economics / Q000517:prevention & control*; D016896:Treatment Outcome