1406. Risk Factors for Surgical Site Infections (SSIs) after Pediatric Spine Operations (PSO)
Session: Oral Abstract Session: Predicting and Preventing SSIs
Sunday, October 23, 2011: 8:15 AM
Room: 157ABC
Background: Few studies have assessed risk factors for SSIs after PSO. Recently, the number of SSIs after these procedures increased at the UICH.

Methods: We performed a case-control study with 72 children (< 18) who had PSOs (laminectomy or spinal fusion) at the UICH from July 2001 to July 2010. Cases were defined as any patient (pt) that < 30 days after a PSO had an SSI as defined by the Centers for Disease Control. Two controls were selected per case from pts who had PSOs before and after the case but did not have SSIs. Demographic data and data on pts’ underlying diseases, medications, operations, hospital stays, and post-operative (post-op) visits were abstracted from medical records, entered into Excel, and analyzed using SAS 9.2. Fisher’s exact test and Student’s t-test were used to compare dichotomous variables and continuous variables, respectively. Variables with p < 0.1 or with biological significance were analyzed with stepwise logistic regression. P-values < 0.05 were considered significant.

Results: The mean age was 13.5 ± 3.7 years for pts with SSI, and 13.4 ±  3.1 years for controls; 12 cases (50%) and 18 controls (37.5%) were male. Of the 24 pts with SSIs, 13 (54.2%) had deep incisional infections and 11 (45.8%) had superficial incisional infections. Six (25%) SSIs were caused by S. aureus (2 isolates were methicillin resistant); 12 were caused by > 2 organisms. Independent pre-op risk factors for SSI were: body mass index (BMI; p = 0.0004; odds ratio [OR] 1.39; 95% confidence interval [CI] 1.2, 1.7), height (p = 0.029; OR 0.96; 95% CI 0.96, 0.99), and insurance type (p = 0.06; OR 0.15; 95% CI 0.03, 0.80). The overall model included: BMI (p = 0.0004; OR 1.4; 95% CI 1.2, 1. 7), blood transfusion during the operation (p = 0.004; OR 270.5; 95% CI 5.9, > 999.9), low intraoperative fraction of inspired O2 (p = 0.006); days in the pediatric intensive care unit after the operation and before the SSI (0.007; OR 1.6; 95% CI 1.1, 2.2). Post-op length of stay was longer for cases than for controls (p = 0.008) and cases were more likely to be readmitted than controls (p = 0.005).

Conclusion: The lowest intraoperative fraction of inspired O2 and intra-op blood transfusions are potentially modifiable risk factors for SSI after PSO.

Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

Lindsay Croft, MS, Epidemiology, University of Iowa College of Public Health, Iowa City, IA, Jean Pottinger, RN, MS, Clinical Quality, Safety, and Process Improvement, University of Iowa Hospitals and Clinics, Iowa City, IA, Christine Ziebold, MD, PhD, MPH, Pediatrics, University of Iowa College of Medicine, Iowa City, IA, Stuart Weinstein, MD, Orthopedics, University of Iowa, Iowa City, IA and Loreen A. Herwaldt, MD, FIDSA, University of Iowa Carver College of Medicine, Iowa City, IA


L. Croft, None

J. Pottinger, None

C. Ziebold, None

S. Weinstein, None

L. A. Herwaldt, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.