1. 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

2. 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

3. Participation in HELICS SSI Procedures No. operationsNo. countries 2000-320042000-32004 CABG28 45312 23478 Cholecystect.30 22516 38088 Colon20 79810 77899 C section30 03519 58098 Hip prosthesis59 27449 4961114 Laminectomy3 1422 91346 Total171 927111 3611314

4. The HELICS Network of Networks (2004) Austria 314 Luxembourg ICU network Netherlands 6225 France 16 560 Spain 2854 Portugal ICU network Belgium 588 England 24910 Northern Ireland 2001 Wales 472 Scotland 5182 Finland 2854 Norway SSI network Poland 6766 Germany 40 437 Lithuania 3340 Humgary 669

5. Proportion of countries’ hospitals contributing data to HELICS

6. Case-mix adjustment: NNIS Risk Index

7. Distribution of risk Index by country Hip prosthesis

8. Type of SSI reported: Hip prosthesis No SSI 42420013132365112039378326410

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

10. 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

11. Proportion of SSI detected after discharge % SSI detected after discharge (Inter-country range*) CABG100 - 47 0 - 100 0 - 33 0 - 83 13 - 100 58 - 100 CHOL31 COLO12 CSEC53 HPRO20 LAM50 * Excludes 4 countries where PDS data not available/collected

12. Daily incidence rate of SSI (all procedures)

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

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

15. Comparison of cumulative incidence and incidence density for hip prosthesis

16. 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 prosthesis2.21.8  Total hip (81.51)1.61.7  Partial hip (81.52)4.02.2 Example: ICD9 CM codes for Hip replacements

17. Inter-country variation in type of hip procedure

18. Conclusions It’s complicated! ….but valuable

19. 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

20. 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

21. 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