Association between Patient-Controlled Analgesia Pump Use and Postoperative Surgical Site Infection in Intestinal Surgery Patients

Background: Patient-controlled analgesia (PCA) pumps are widely used after surgery, but their association with various outcomes is not completely understood. Is PCA pump use related to the incidence of postoperative surgical site infections among patients undergoing open intestinal surgery?

Materials and Methods: We undertook a comprehensive retrospective chart review of 515 randomly selected patients over age 18 who had major rectal or intestinal surgery (Diagnosis Related Groups [DRGs] 146-149) between January 1994 and March 1997 from eight community or teaching hospitals along the U.S. west coast. Of these patients, 214 used PCA pumps. Outcome measures were in-hospital postoperative surgical site infections, respiratory complications, ileus/abdominal distention, urinary tract infection/urinary retention, and length of stay.

Results: Use of a PCA pump was significantly associated with increased in-hospital postoperative surgical site infections (10.7% for PCA, 4.0% for no PCA). The odds ratio for PCA use was about 4.0 after controlling for many variables, including severity of illness at admission, body mass index, preadmission use of corticosteroids, perforated viscus, number of previous abdominal operations, wound classification category, hypothermia, malnutrition on admission, preoperative antibiotic use within 2 h before incision, time from hospital admission to surgery, skin prep to incision time, anesthesia start to incision time, surgical skin to skin time, wound closure type, time from incision closure to the start of PCA, use of drains, blood product use, central line use, line infection, mobility assistance required, hospital, DRG, and surgeon.

Conclusion: No confounding variables explained the significant association between PCA pump use and in-hospital surgical site infection. These results stand firmly on data that merit additional study to further elucidate possible immunologic effects of PCA pumps.