Unadjusted clinical and financial outcomes^a of 150 patients with methicillin-resistant <i>Staphylococcus aureus</i> surgical site infections (SSI) compared with 231 uninfected controls and 128 patients with methicillin-susceptible <i>S. aureus</i> SSI.

a<p>P values calculated using Student t test or Wilcoxon rank sum test for continuous variables. P-values, odds ratios, and 95% confidence intervals for categorical variables were calculated using the Cochran-Mantel-Haenszel test (MRSA SSI v. matched-uninfected controls) and the Fisher exact test or chi-square (MRSA SSI v MSSA SSI). All percentages were calculated using denominators that excluded missing data.</p>b<p>Denominator includes patients who survived their index admissions.</p>c<p>Financial data were available for 144 cases (96%), 202 (87%) uninfected controls, and 127 (99%) MSSA SSI controls.</p

Independent Predictors of Post-Operative Adverse Outcomes: Analysis of 150 patients with methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) surgical site infections (SSI) compared with 128 patients with methicillin-susceptible <i>S. aureus</i> (MSSA) SSI to determine independent effect of methicillin-resistance on patients with <i>S. aureus</i> SSI.

a<p>Patients who died during the index admission (n = 23) were excluded from this analysis. Final model controlled for the confounding effect of Medicaid insurance. Reference model also included the following variables: Charlson score ≥3, wound class >2, ASA score ≥3, surgery on same day as admission, post-operative glucose >200 mg/dl, and receipt of effective antimicrobial therapy after infection.</p>b<p>Final model controlled for the confounding effects of age, ASA score, coronary artery bypass graft procedure, and admission to the ICU prior to infection. Reference model also included the following variables: Medicaid insurance, Charlson score ≥3, post-operative glucose >200 mg/dl, and receipt of effective antimicrobial therapy after infection.</p>c<p>Final model controlled for the confounding effects of surgical duration >75^th NNIS percentile. Reference model also contained the following variables: BMI ≥30, age ≥65 years, admission from home, McCabe score = 1, post-operative glucose >200 mg/dl, coronary artery bypass grafting, orthopedic procedure, and appropriate administration of peri-operative antimicrobial prophylaxis.</p>d<p>Final model controlled for confounding effects of Charlson score ≥3 and coronary artery bypass graft surgery. Reference model also contained the following variables: age ≥65 years, admission from home, lack of independence with ambulation, McCabe score = 1, post-operative serum glucose >200 mg/dL, and orthopedic procedure.</p

Length of stay and hospital charges ^a within 90 days of surgery attributable to surgical site infection (SSI) due to methicillin resistant <i>Staphylococcus aureus</i> (MRSA): SSI due to MRSA compared to SSI due to MSSA.

a<p>Charges were normalized to year 2003 by adjusting for inflation at a rate of 0.03% per year.</p>b<p>Adjusted for surgical duration >75^th NNIS percentile, ASA score ≥3, procedure at tertiary care hospital, Charlson score ≥3, and surgery on same day as admission.</p>c<p>Adjusted for surgical duration >75^th NNIS percentile, ASA score ≥3, procedure at tertiary care hospital, Charlson score ≥3, surgery on same day as admission, and coronary artery bypass graft surgery.</p

Length of stay and hospital charges ^a within 90 days of surgery attributable to surgical site infection (SSI) due to methicillin resistant <i>Staphylococcus aureus</i> (MRSA): SSI due to MRSA compared to uninfected controls.

a<p>Charges were normalized to year 2003 by adjusting for inflation at a rate of 0.03% per year.</p>b<p>Adjusted for procedure at tertiary care hospital, need assistance with ≥3 ADLs, post-operative serum glucose >200 mg/dL, orthopedic procedure, caucasian race, McCabe score = 1, male sex, coronary artery bypass graft procedures, surgical duration >75^th NNIS percentile, and contained a term for the interaction of MRSA SSI and need assistance with 3 or more ADLs.</p>c<p>Adjusted for procedure at tertiary care hospital, coronary artery bypass graft procedure, surgical duration >75^th NNIS percentile, procedure on same day as admission, ASA score ≥3, the interaction between MRSA SSI and need assistance with 3 or more ADLs and the interaction between MRSA SSI and procedure at a tertiary care hospital.</p

Survival analysis of cases and controls.

<p>Kaplan-Meier Survival Analysis of mortality among patients with surgical site infection (SSI) due to methicillin resistant <i>Staphylcoccus aureus</i>, SSI due to methicillin-susceptible <i>S. aureus</i>, and uninfected controls.</p

Infection and Treatment Data for 1,470 patients with bloodstream infection (BSI) in nine community hospitals, 2003–2006^a.

a<p>Missing data: type of BSI (n = 3), location of acquisition of BSI (n = 4), central line present at BSI (n = 51).</p

Logistic Regression Model^a to Identify Variables Independently Associated with Failure to Receive Appropriate Empiric Antimicrobial Therapy.

a<p>Model included a generalized effect estimate to account for clustering among hospitals and included the following confounders: admission from a facility (p = 0.17), presence of a central line at the time of BSI (p = 0.53), in the ICU prior to BSI onset (p = 0.59), and presence of a Foley catheter at the time of admission (p = 0.82).</p>b<p>Two interaction terms were included in the model: Interaction between Charlson score and community-onset, healthcare associated location of acquisition (0.04) and interaction between Charlson score and hospital-onset, healthcare associated location of acquisition. No specific effect measure available for these variables due to interaction.</p>c<p>Multi-level variable, therefore no effect measure available.</p

Distribution of pathogens based on location of acquisition of bloodstream infection (BSI) among 1,470 patients admitted to 9 community hospitals, 2003–2006.

<p>[FOOTNOTE] * CA = community-acquired, CO-HCA = community-onset, healthcare-associate, HO-HCA; hospital-onset, healthcare-associated, CoNS = coagulase negative Staphylococci.</p

Outcomes data for 1,470 patients with bloodstream infection (BSI) in nine community hospitals, 2003–2006^a.

a<p>Missing data: Week following BSI outcomes (n = 9), procedures after BSI (n = 24), PICC placement (n = 22), discharge status (n = 5), readmitted within 90 days (n = 9), returned to ED (n = 85).</p>b<p>Excludes 87 patients in ICU prior to BSI.</p

Microbiology of 1,514 isolates from 1,470 patients with bloodstream infection in community hospitals^a.

a<p>Isolates that led to <10 bloodstream infections are not included.</p