Wound infection surveillance program at the National Cancer Institute of Mexico

Objectives. To evaluate the results of a prospective wound infection surveillance program during its first semester of operation, and to analyse the risk factors associated to wound infection. Methods and design. From January 01 to June 30 1993, 1103 surgeries were prospectively followed. The incidence rates of infection were calculated and a case control analysis was done to evaluate the associated risk factors to POWI (postoperative wound infection). Setting. An oncological tertiary-care center. Results. The POWI rate was 9.0 per 100 surgeries. By univariate analysis the associated risk factors were: obesity (OR = 2.07 Cl95% = 1.19-3.64), one drainage (OR = 2.10 CI = 1.33-3.31), two drainages (OR = 3.14 CI = 1.85-5.26), length of stay of the drainage (patients with wound infection: 15.2 +/- 6.7 days vs. patients without wound infection: 8.2 +/- 6.6 days), duration of operation (patients with wound infection: 188 +/- 163 minutes vs. patients without wound infection: 122 +/- 127 minutes) and duration of preoperative hospitalization (patients with wound infection: 2.9 +/- 6.4 days vs. patients without wound infection: 1.5 +/- 3.0 days). The associated risk factors by regression analysis were: obesity (OR = 1.93 Cf = 1.08-3.43), two drainages (OR = 2.09 CI = 1.03-4.05) duration of operation > = 120 minutes (OR = 1.96 CI = 1.00-3.86) and duration of preoperative hospitalization (OR = 1.03 CI = 1.00-1.09). Conclusions. The program showed a previous under-reporting of POWI from 4.2-4.8 per 100 surgeries in the previous seven years to 9.0 in the first semester of operation. It also identified the associated risk factors to POWI in our institution.