THE EFFECT OF SURGICAL-WOUND INFECTION ON POSTOPERATIVE HOSPITAL STAY

Objective: To determine the effect of surgical wound infection on post operative duration of hospital stay. Design: A case-control study nest ed within a cohort. Setting: A tertiary-care hospital. Patients: Selec ted from a cohort of 4702 inpatients who underwent surgical procedures over a 12-month period. There were 3602 patients, 1100 having been ex cluded because of lack of infection associated with a particular surgi cal procedure, because of ''lumping'' of procedures under a nonhomogen eous heading or because a procedure was unlikely to be the reason for the patient's hospitalization. Main Outcome Measure: Postoperative dur ation of hospital stay. Results: In the cohort 89 wound infections wer e identified, 73 of these occurring with procedures selected for study . Five patients were excluded from the study because of data deficienc ies, leaving 68 patients who underwent 15 different procedures. These were compared with 136 control patients selected by stratified random sample from a list of patients who underwent the same risk-indexed pro cedure in the same surgical division. Wound infection patients and con trols did not differ in anesthetic risk score or procedure duration. P atients with infection remained in hospital 19.5 days longer than cont rols (95% confidence interval, range from 11.0 to 27.9 days). Deep-sea ted infections prolonged the hospital stay more than superficial incis ional infections (24.3 versus 13.2 days). Conclusions: Surgical wound infection markedly prolonged the duration of hospitalization in the Un iversity of Alberta Hospitals, longer than that documented in previous studies in other countries. Maximizing opportunities to prevent wound infection would be beneficial to both patients and hospitals.