Is There Room For Prevention? Examining The Effect Of Outpatient Facility Type On The Risk Of Surgical Site Infection. Open Access

Parikh, Rishi Vimal (2015)

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Background: Surgical site infections in the inpatient setting have been the focus of much of the previous work on SSI. However, previous risk-adjustment models and analyses have largely ignored the volume of surgical procedures performed in the outpatient setting. This study examined whether the SSI risk for surgical breast procedures is less in ambulatory surgery centers compared to hospital-based outpatient facilities, after adjusting for differences in patient case-mix between facility type and risk of breast SSI.

Methods: Data for this study was obtained from the National Healthcare Safety Network (NHSN), a secure, Internet-based surveillance system managed by the Division of Healthcare Quality and Promotion (DHQP) at the Centers for Disease Control and Prevention (CDC). Unconditional multivariable logistic regression was used to examine the association between facility type and breast SSI.

Results: Out of 86,199 total outpatient breast procedures reported to NHSN between 2010 and 2013, 77,224 were used in the analysis. For patients aged 51 or under, the risk of SSI among ambulatory surgery centers was 0.28 (95% CI: 0.18, 0.44) times the risk of SSI among hospital-based outpatient settings, adjusted for age, ASA class and duration of procedure. For patients older than 51 years, the risk of SSI among ambulatory surgery centers was 0.23 (95% CI: 0.14, 0.39) times the risk of SSI among hospital-based outpatient settings, adjusted for age, ASA class and duration of procedure.

Conclusions: Ambulatory surgery centers have a protective effect on the risk of breast SSI compared to hospital-based outpatient settings, the extent of which differs by age. Though this study may has its limitations, including possible low sensitivity and incomplete control for patient case-mix, these findings strongly suggest that there is bridgeable gap in SSI prevention practices between hospital-based outpatient settings and ASCs. Future studies should examine mechanisms leading to this difference in risk, and target interventions accordingly.

Table of Contents

Chapter I: Literature Review 1

Healthcare-Associated Infections 1

Definitions and Burden 1

History, Surveillance, and Prevention 2

Surgical Site Infections 5

Definitions and Burden 5

Surveillance and Prevention 6

Outpatient Facilities 9

Definitions and Burden 9

Surveillance and Prevention 10

Chapter II: Manuscript 12

Introduction 12

Methods 14

Data Source 14

Analysis Dataset and Variable Specification 14

Statistical Analyses 17

Results 19

Discussion 21

References 25

Tables 33

Appendix 36

Chapter III: Summary, Public Health Implications, and Future Directions 45

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