Surveillance of Surgical Site Infection Surveillance of Surgical Site Infection An overview of results (2004) Jennie Wilson Programme Lead – SSI surveillance Service, England Hospitals in Europe Link in Infection Control through Surveillance

SSI surveillance protocol Patient level dataset Patient level dataset NNIS risk index NNIS risk index Type of procedure Type of procedure Age/sex Age/sex CDC definition for SSI CDC definition for SSI Micro-organism data optional Micro-organism data optional Surveillance methods – potential variation Surveillance methods – potential variation Intensity of case-finding Intensity of case-finding Post-discharge surveillance Post-discharge surveillance Interpretation of definitions Interpretation of definitions

Participation in HELICS SSI Procedures No. operationsNo. countries CABG Cholecystect Colon C section Hip prosthesis Laminectomy Total

The HELICS Network of Networks (2004) Austria 314 Luxembourg ICU network Netherlands 6225 France Spain 2854 Portugal ICU network Belgium 588 England Northern Ireland 2001 Wales 472 Scotland 5182 Finland 2854 Norway SSI network Poland 6766 Germany Lithuania 3340 Humgary 669

Proportion of countries’ hospitals contributing data to HELICS

Case-mix adjustment: NNIS Risk Index

Distribution of risk Index by country Hip prosthesis

Type of SSI reported: Hip prosthesis No SSI

Median post-operative length of hospital stay & inter-country variation

Post-discharge surveillance Not a requirement in all countries Not a requirement in all countries Variation in PDS intensity Variation in PDS intensity Application of case definitions Application of case definitions

Proportion of SSI detected after discharge % SSI detected after discharge (Inter-country range*) CABG CHOL31 COLO12 CSEC53 HPRO20 LAM50 * Excludes 4 countries where PDS data not available/collected

Daily incidence rate of SSI (all procedures)

Rates (cumulative incidence) of SSI by surgical category (95%CL)

Cumulative incidence of SSI by category (inter-country range) Incidence density of SSI by category (inter-country range)

Comparison of cumulative incidence and incidence density for hip prosthesis

Potential impact of case-mix Cumulative incidence Incidence density % SSI at 30 days post-op In-hospital SSI per 1000 post-op days All hip prosthesis  Total hip (81.51)  Partial hip (81.52) Example: ICD9 CM codes for Hip replacements

Inter-country variation in type of hip procedure

Conclusions It’s complicated! ….but valuable

Limitations Differences in patient and operation characteristics Differences in patient and operation characteristics Risk index Risk index Age Age Procedure type Procedure type Differences in case finding Differences in case finding Type of SSI Type of SSI Differences in length of inpatient stay Differences in length of inpatient stay PDS – intensity PDS – intensity Discharge data Discharge data

Opportunities Large dataset Large dataset Includes PDS data Includes PDS data Explore relationships with time post-op Explore relationships with time post-op Develop risk models Develop risk models Useful comparators Useful comparators Common protocol a major achievement Common protocol a major achievement Framework to encourage SSI surveillance Framework to encourage SSI surveillance Need to enhance Need to enhance micro data micro data PDS PDS Procedure codes Procedure codes

Acknowledgements HELICS data analysis group, especially Ilse Ramboer and Carl Suetens HELICS data analysis group, especially Ilse Ramboer and Carl Suetens Surveillance networks & their co-coordinators Surveillance networks & their co-coordinators