Surgical site infections in the NICU

Surgical site infections (SSI) increase morbidity and mortality. In adult and pediatric populations, the incidence ranges from 1.5-12%. Studies in neonates have shown an association between preoperative stay in an intensive care unit and development of SSI. To date, there has only been a single study looking exclusively at SSI in the Neonatal Intensive Care Unit (NICU). Additionally, there has been a suggestion that prematurity may be a risk factor for SSI, but this has come from studies looking at all neonates less than 28days, rather than only neonates hospitalized in a NICU.

Primary outcome variable was to calculate the incidence of SSI in a NICU population. Secondary outcome variables were to determine if SSI is more common in premature infants and to identify additional risk factors for the development of SSI.

An IRB-approved retrospective chart review of all patients undergoing surgical procedures in a level IIIC NICU over a 2-year period was used. We utilized the CDC's definitions of surgical procedures and SSI. An epidemiologist reviewed charts if the diagnosis of SSI was questionable. Statistical analysis was done with t test and Fisher's exact test.

We identified 165 patients who underwent 264 surgical procedures. Incidence of SSI was 11.7%. There were 31 SSI that occurred in 29 neonates over the 2-year period, with no mortality in that group. In patients who developed an SSI, 34.5% occurred after the 1st procedure, 41.4% occurred after a 2nd procedure, and 24.1% occurred after the 3rd or later procedure. There was no difference in perioperative antibiotic usage.

This study describes SSI in a strictly neonatal population in a large academic NICU. Prematurity does not appear to be a risk factor for SSI. SSI is more common in neonates who have undergone an abdominal procedure or multiple procedures. Perioperative antibiotics are not significantly associated with prevention of SSI.