SSI surveillance: a combined approach

Consistent, impartial and accurate surveillance schemes drive improvement and reduce wound infection rates (Geubbels et al 2006). The Royal Brompton and Harefield NHS Foundation Trust has participated in the Health Protection Agency (HPA) Surgical Site Infection Surveillance Service (SSISS) coronary artery bypass graft (CABG) module since 2003, and the cardiac (non- CABG) module since April 2010. Despite the significant advantages of participating in the national surgical site infection (SSI) scheme, there are important interventions and patient groups not covered by HPA 2011 protocol. It is unsurprising, therefore, that local SSI surveillance schemes remain persuasive with regards to clinical improvement and patient outcomes. This article advocates participation in the broader surveillance HPA scheme and investigates the importance of robust local SSI surveillance, using the examples of donor wound infection and a new area of interest, cardiology implant device surveillance.

HPA SSI Surveillance Scheme

The HPA (2011) classifications and definitions of SSI are useful across a wide range of surgical categories (see Fig. 1). Participating in the HPA scheme provides for national benchmarking of SSI rates and contributes to the clinical governance framework (Rochon 2012). In addition, though not limited to these, other key benefits to participating in the national SSI surveillance scheme include:
• Data quality assurance: The HPA surveillance protocol and validation processes provide a strong foundation for data quality assurance. Hospitals with the HPA SSI surveillance programme are able to demonstrate many of the data quality indicator criteria of accuracy, validity, reliability, timeliness, relevance, and completeness (Audit Commission 2007).
• Outlier notification: The HPA undertakes a statistical assessment of the SSI data on a quarterly basis to identify hospitals with SSI rates that meet the outlier criteria based on national percentiles. ‘Within a surgical category, hospitals are notified as high outliers if their SSI rates are above the 90th percentile or low outliers if their SSI rates fall below the 10th percentile’ (Elgohari 2012). In Figure 2, high outlier notifications from the HPA re-enforced the local findings (i.e. 2 beyond sigma). The designation of high outlier status prompted the hospital to investigate its infection control practices, case mix and surveillance methodologies with expert input and support from the HPA. As a result of the work to reduce SSI rates, the hospital has since maintained its rates at or below the national benchmark for eight consecutive quarters.
• Re-admission for wound infection data: The required inpatient component of SSI surveillance includes re-admission for wound infection within 30 days of primary procedure (all SSI categories) which may be of interest to commissioning bodies in the future. Data on re-admission for SSI is also maintained up to one year for procedures including implant (deep/organ or space only) (HPA 2011).
• Post discharge SSI surveillance: The HPA (2011) also maintains data on wound infections not requiring re-admission to hospital for treatment, with facilities to record SSIs identified in outpatient visits to ward or clinic for SSI care and/or patient questionnaires and follow-up.