Health insurance database for post-discharge surveillance of surgical site infection following arthroplasty

Surgical site infection surveillance (SSI) is important for the improvement of care and patient safety. Most SSI surveillance systems focus on hospital settings, whereas numerous infectious events occur after discharge.

To evaluate the patient care trajectory after discharge, we linked the hospital discharge database and the National Health Insurance Cross-Schemes Information System (NHI-CIS) to trace hip or knee arthroplasty infection (HKAI).

A retrospective analysis was performed using the permanent 1/97th sample of the whole NHI-CIS database. A total of 1739 patients underwent hip or knee arthroplasty between January 1st, 2011 and December 31st, 2011. Patients rehospitalized for HKAI were detected using a specific published algorithm. Non-rehospitalized HKAI patients were identified using a novel tracking algorithm based on ambulatory care consumption: nurse intervention, antibiotics and bandage purchase.

Of the 1739 studied patients, 20 patients (1.1%) were rehospitalized for HKAI. Fourteen (70%) of the HKAI events occurred within the first two months after surgery, two occurring during the patients' surgical hospital stay. Using ambulatory care data, 10 additional cases were suspected of developing HKAI in the year following their surgery. HKAI incidence rate was then estimated to be 1.76% (95% confidence interval: 1.14-2.38%).

Although the study sample was limited, we demonstrated that each HKAI occurring after discharge could not be traced by the in-hospital information system alone. This result emphasizes the need for having a passive routine tool for post-discharge surveillance such as the NHI-CIS database.