## CDC Classification of Surgical Site Infections **Key Point:** The CDC defines the temporal window for SSI classification based on the depth of infection and type of surgery. ### Temporal Criteria for SSI | SSI Type | Time Window | Definition | |----------|-------------|------------| | Superficial incisional | ≤30 days | Involves skin and subcutaneous tissue only | | Deep incisional | ≤30 days (≤90 days if implant) | Involves fascia and muscle layers | | Organ/space | ≤30 days (≤90 days if implant) | Involves any organ/space opened during surgery | **High-Yield:** The 30-day window applies to all SSI types for non-implant surgeries. For procedures involving implantation of prosthetic material, the window extends to 90 days. **Clinical Pearl:** Infections occurring after these time windows are classified as nosocomial infections rather than SSIs, which has implications for quality metrics and reporting. **Mnemonic:** **SSI-30** — Superficial, deep, and organ-space SSIs occur within 30 days (or 90 days if implant placed). ### Rationale The 30-day cutoff reflects the typical inflammatory phase of wound healing and helps distinguish true surgical complications from unrelated healthcare-associated infections acquired during the hospital stay or after discharge.
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.