title: Dipslide culture in colonic surgery: a tool for assessment of surgical performance and a guide to antibiotic use.
abstract: We evaluated a bacterial culture system for the assessment of surgical performance during colorectal operations, and for assessing the impact of selective postoperative antibiotics in contaminated cases. Surgically related infections were recorded and their risk factors were estimated, using univariate and multivariate methods, in 1079 patients undergoing elective colorectal operations. (Study period 1 was prospective, controlled and randomized, and study period 2 was prospective and open). All the patients were given metronidazole, 1 g i.v., at induction of anaesthesia and 12 h postoperatively. The number of colony-forming units (CFU) on an intraoperative dipslide culture was classified as 0, 1-4 or > or = 5 (n = 591, 183 and 305). Patients with > or = 5 CFU were randomized to receive either no further antibiotics or cefuroxime (1.5 g, i.v. every 8 h for 2 days) during the first study period (30 months). During the second period (84 months), all patients with > or = 5 CFU were to be given cefuroxime. Increasing age (p = 0.014), postoperative transfusion of packed red blood cells (p < 0.001), and high bacterial numbers (p < 0.001) were independently associated with infection. Surgeon-related rates of operative bacterial contamination varied between 12 and 50% (p < 0.001). In patients given only metronidazole, the likelihood of infection rose as the density of bacteria in the wound increased according to a sigmoid dose-response curve (5.1, 9.8 and 47.5% with CFU 0, 1-4 and > or = 5, respectively). In the category with > or = 5 CFU, 265 patients were treated with cefuroxime and 23 (8.7%) subsequently had infections [corrected]. Of 40 patients with > or = 5 CFU who did not receive cefuroxime postoperatively, 19 developed infections (p < 0.001, relative risk 5.47; 95% confidence interval 3.29-9.10). In conclusion, dipslide culture can identify patients at high risk of infection after colonic operations. It can be used to assess surgical performance. The addition of postoperative antibiotic cover for aerobic bacteria, detected by the dipslide, reduced the risk of infection more than 5-fold and almost eliminated the risk of contamination.
authors.affiliation: Department of Clinical Microbiology, Kärnsjukhuset, Skövde, Sweden.
authors.forename: B E
authors.initials: BE
authors.lastname: Claesson
authors.forename: S
authors.initials: S
authors.lastname: Filipsson
authors.forename: D E
authors.initials: DE
authors.lastname: Holmlund
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001424:Bacterial Infections / Q000382:microbiology / Q000517:prevention & control; D001431:Bacteriological Techniques; D002444:Cefuroxime / Q000627:therapeutic use; D002511:Cephalosporins / Q000627:therapeutic use; D002648:Child; D003108:Colonic Diseases / Q000601:surgery*; D015169:Colony Count, Microbial; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use; D008875:Middle Aged; D011336:Probability; D011446:Prospective Studies; D012307:Risk Factors; D013530:Surgical Wound Infection / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D008795:Metronidazole; D002444:Cefuroxime