The timing of prophylactic administration of antibiotics and the risk of surgical-wound infection.

BACKGROUND Randomized, controlled trials have shown that prophylactic antibiotics are effective in preventing surgical-wound infections. However, it is uncertain how the timing of antibiotic administration affects the risk of surgical-wound infection in actual clinical practice. METHODS We prospectively monitored the timing of antibiotic prophylaxis and studied the occurrence of surgical-wound infections in 2847 patients undergoing elective clean or "clean-contaminated" surgical procedures at a large community hospital. The administration of antibiotics 2 to 24 hours before the surgical incision was defined as early; that during the 2 hours before the incision, as preoperative; that during the 3 hours after the incision, as perioperative; and that more than 3 but less than 24 hours after the incision, as postoperative. RESULTS Of the 1708 patients who received the prophylactic antibiotics preoperatively, 10 (0.6 percent) subsequently had surgical-wound infections. Of the 282 patients who received the antibiotics perioperatively, 4 (1.4 percent) had such infections (P = 0.12; relative risk as compared with the preoperatively treated group, 2.4; 95 percent confidence interval, 0.9 to 7.9). Of 488 patients who received the antibiotics postoperatively, 16 (3.3 percent) had wound infections (P less than 0.0001; relative risk, 5.8; 95 percent confidence interval, 2.6 to 12.3). Finally, of 369 patients who had antibiotics administered early, 14 (3.8 percent) had wound infections (P less than 0.0001; relative risk, 6.7; 95 percent confidence interval, 2.9 to 14.7). Stepwise logistic-regression analysis confirmed that the administration of antibiotics in the preoperative period was associated with the lowest risk of surgical-wound infection. CONCLUSIONS We conclude that in surgical practice there is considerable variation in the timing of prophylactic administration of antibiotics and that administration in the two hours before surgery reduces the risk of wound infection.

[1]  H. Stone Basic principles in the use of prophylactic antibiotics. , 1984, The Journal of antimicrobial chemotherapy.

[2]  R. Moleski,et al.  Role of the infectious disease specialist in containing costs of antibiotics in the hospital. , 1986, Reviews of infectious diseases.

[3]  Polk Hc,et al.  Postoperative wound infection: a prospective study of determinant factors and prevention. , 1969, Surgery.

[4]  R M Gardner,et al.  Improved perioperative antibiotic use and reduced surgical wound infections through use of computer decision analysis. , 1989, Infection control and hospital epidemiology.

[5]  M. O'Connor,et al.  Surgical Wound Infections: A 5‐Year Prospective Study of 20,193 Wounds at the Minneapolis VA Medical Center , 1984, Annals of surgery.

[6]  B. Rosner,et al.  Use of antimicrobial drugs in general hospitals: patterns of prophylaxis. , 1979, The New England journal of medicine.

[7]  T. K. Hunt Surgical wound infections: an overview. , 1981, The American journal of medicine.

[8]  J. Burke The effective period of preventive antibiotic action in experimental incisions and dermal lesions. , 1961, Surgery.

[9]  S Greenfield,et al.  The state of outcome research: are we on target? , 1989, The New England journal of medicine.

[10]  D. Burdon Principles of antimicrobial prophylaxis , 1982, World journal of surgery.

[11]  D. Hosmer,et al.  Applied Logistic Regression , 1991 .

[12]  H. Stone,et al.  Antibiotic Prophylaxis in Gastric, Biliary and Colonic Surgery , 1976, Annals of surgery.

[13]  D. Ballard,et al.  Effectiveness research and assessment of clinical outcome: a review of Federal Government and medical community involvement. , 1990, Mayo Clinic proceedings.

[14]  E. Bergquist,et al.  Prophylactic antibiotics for surgery. , 1987, The Medical clinics of North America.

[15]  A. B. Kaiser Antimicrobial prophylaxis in surgery. , 1986, The New England journal of medicine.

[16]  N. J. Ehrenkranz,et al.  Surgical wound infection occurrence in clean operations; risk stratification for interhospital comparisons. , 1981, The American journal of medicine.

[17]  W. Roper,et al.  Effectiveness in Health Care , 1988 .

[18]  T. Sacks,et al.  A decisive period in the antibiotic prophylaxis of cutaneous lesions caused by Bacteroides fragilis in guinea pigs. , 1980, The Journal of infectious diseases.

[19]  T. K. Hunt,et al.  Antibiotic prophylaxis in surgical procedures. A critical analysis of the literature. , 1983, Archives of surgery.

[20]  P Diehr,et al.  Regression Analysis in Health Services Research: The Use of Dummy Variables , 1982, Medical care.