Immediate-Use Steam Sterilization (IUSS)

IUSS (Immediate-Use Steam Sterilization), formerly called "flash sterilization," is the sterilization of an unwrapped or minimally wrapped patient care item for immediate use when there is insufficient time for terminal sterilization through the normal cycle.

---

When IUSS Is Acceptable

IUSS is intended for emergency situations only:

• A needed instrument is accidentally dropped or contaminated during a procedure
• The only available instrument for a critical procedure becomes non-sterile
• A patient's life or safety is at immediate risk without the instrument

When IUSS Is NOT Acceptable

• Convenience — to avoid waiting for a full sterilization cycle
• Insufficient inventory — indicates a systemic problem that must be addressed by purchasing more instruments
• Routine processing — IUSS should never be a standard practice for any instrument set
• Implants — IUSS is strongly discouraged for implantable devices (BI cannot be read before use)
• Saving time — schedule and process instruments through normal cycles

AAMI, AORN, TJC, and CMS all state that IUSS should be kept to a minimum and is NOT a substitute for adequate instrument inventory.

---

IUSS Cycle Parameters

Gravity Displacement IUSS:

Prevacuum IUSS:

---

IUSS Monitoring Requirements

Even though IUSS is an emergency process, it still requires monitoring:

1. Mechanical monitoring — verify time, temperature, pressure on the cycle printout
2. Chemical indicator — place a CI with the item (at minimum, a Class 5 integrating indicator)
3. Biological indicator — run a BI with each IUSS cycle or at least daily when IUSS is used
4. Documentation — record the reason for IUSS, the item processed, cycle parameters, patient information, and technician ID

---

IUSS Tracking and Metrics

Facilities should monitor IUSS frequency as a quality indicator:

A high IUSS rate signals a system problem — not a sterilization success. It indicates the facility lacks adequate instrumentation to support the surgical schedule through standard sterilization.

---

Transport of IUSS Items

Since IUSS items are unwrapped or minimally wrapped, transport must be aseptic:

• Transport in a covered, rigid container specifically designed for IUSS items
• Transport directly from the sterilizer to the sterile field
• Minimize time between sterilizer and sterile field
• The item should be used only for the patient and procedure for which it was sterilized
• Never store an IUSS-processed item — if not used immediately, it must be reprocessed through a full cycle