Pectus excavatum repair (PEX) is among the most painful thoracic procedures performed. Continuous peripheral nerve blockade (CPNB) is known to be efficacious in optimizing pain control while limiting narcotic use in adult thoracic procedures. It was introduced in May 2015 as a bridge to oral pain control in children undergoing PEX. Consequently, the surgical site infection (SSI) rate increased from 2.7% to 27.7%.SSI surveillance followed national guidelines. The abrupt increase prompted root cause analysis and cessation of CPNB use. A dynamic systems model of SSI in PEX was developed. Statistical analysis compared SSI outcomes with and without CPNB.From May 2015 to June 2015, 21 PEX were performed; 11 with CPNB. 6 SSIs were observed. Use of CPNB significantly (p=0.008) increased SSI incidence. Haller index, number of bars, usage of Fiberwire®, methicillin resistant S. aureus colonization and length of stay did not differ. Root cause analysis revealed the proximity of CPNB catheters to the wound, the use of CPNB with implanted hardware and a delayed utilization of CPNB catheters to be of concern.Introduction of CPNB coincided with a significant increase in SSI. Further study is needed to assess the safety of CPNB in pediatric PEX.Level III treatment study.