OBJECTIVE: To assess the impact of an automated intraoperative alert to redose prophylactic antibiotics in prolonged cardiac operations.DESIGN: Randomized, controlled, evaluator-blinded trial. SETTING: University-affiliated hospital. PATIENTS:Patients undergoing cardiac surgery that lasted more than 4 hours after the preoperative administration of cefazolin, unless they were receiving therapeutic antibiotics at the time of surgery.INTERVENTION: Randomization to an audible and visual reminder on the operating room computer console at 225 minutes after the administration of preoperative antibiotics (reminder group, n = 137) or control (n = 136). After another 30 minutes, the circulating nurse was required to indicate whether a follow-up dose of antibiotics had been administered. RESULTS:Intraoperative redosing was significantly more frequent in the reminder group (93 of 137; 68%) than in the control group (55 of 136; 40%) (adjusted odds ratio, 3.31; 95% confidence interval, 1.97 to 5.56; P < .0001). The impact of the reminder was even greater when compared with the 6 months preceding the study period (129 of 480; 27%; P < .001), suggesting some spillover effect on the control group. Redosing was formally declined for 19 of the 44 patients in the reminder group without redosing. The rate of surgical-site infection in the reminder group (5 of 137; 4%) was similar to that in the control group (8 of 136; 6%; P = .42), but significantly lower than that in the pre-study period (48 of 480; 10%; P = .02).CONCLUSION: The use of an automatic reminder system in the operating room improved compliance with guidelines on perioperative antibiotic prophylaxis (Infect Control Hosp Epidemiol 2003;24:13-16).Perioperative antibiotic prophylaxis is among the most effective methods to reduce the incidence of surgicalsite infections for many types of surgical procedures. 1 However, its efficacy has been shown to diminish during long procedures. 24 This diminished efficacy has prompted recommendations to redose the antibiotic during procedures of prolonged duration.15 " 8 Despite these recommendations, intraoperative redosing is often omitted. 9 We therefore developed an audible alarm and message delivered via computer consoles in the operating rooms to remind surgical teams to consider intraoperative redosing of antibiotics at the time such antibiotics appeared to be indicated. The purpose of this randomized, controlled study was to quantify the impact of this reminder system on redosing of antibiotics during prolonged cardiac procedures. M E T H O D SPatients undergoing operations between March 23 and June 23, 2000, in the Division of Cardiac Surgery at Brigham and Women's Hospital, Boston, Massachusetts, were evaluated for inclusion in this prospective, randomized, controlled study. The study was approved by the institutional review board.All patients were allocated to either activation of an automated reminder system or no intervention (control), based on a case number assigned to every surgical procedure performed in the h...

Intraoperative redosing of prophylactic antibiotics is recommended for prolonged surgical procedures, although its efficacy has not been assessed. We retrospectively compared the risk of surgical site infections in 1,548 patients who underwent cardiac surgery lasting >240 min after preoperative administration of cefazolin prophylaxis. The overall risk of surgical site infection was similar among patients with (43 [9.4%] of 459) and without (101 [9.3%] of 1,089) intraoperative redosing (odds ratio [OR] 1.01, 95% confidence interval [CI] 0.70-1.47). However, redosing was beneficial in procedures lasting >400 min: infection occurred in 14 (7.7%) of 182 patients with redosing and in 32 (16.0%) of 200 patients without (adjusted OR 0.44, 95% CI 0.23-0.86). Intraoperative redosing of cefazolin was associated with a 16% reduction in the overall risk for surgical site infection after cardiac surgery, including procedures lasting <240 min.

Intraoperative redosing of prophylactic antibiotics is recommended for prolonged surgical procedures, although its efficacy has not been assessed. We retrospectively compared the risk of surgical site infections in 1,548 patients who underwent cardiac surgery lasting >240 min after preoperative administration of cefazolin prophylaxis. The overall risk of surgical site infection was similar among patients with (43 [9.4%] of 459) and without (101 [9.3%] of 1,089) intraoperative redosing (odds ratio [OR] 1.01, 95% confidence interval [CI] 0.70-1.47). However, redosing was beneficial in procedures lasting >400 min: infection occurred in 14 (7.7%) of 182 patients with redosing and in 32 (16.0%) of 200 patients without (adjusted OR 0.44, 95% CI 0.23-0.86). Intraoperative redosing of cefazolin was associated with a 16% reduction in the overall risk for surgical site infection after cardiac surgery, including procedures lasting <240 min.