Medical Device UDI Explained: DI, PI, and GUDID

Read the two parts correctly

The DI is the mandatory fixed portion. The PI is conditional and can include manufacturing or expiry data. A barcode may encode both. Confusing a model-level DI with an individual serial number can cause a faulty recall search or inventory match.

Where UDI appears

FDA generally requires applicable labelers to place UDI on labels and packages, subject to exceptions or alternatives. Certain reusable devices intended for reprocessing require direct marking. Labelers also submit specified device information to GUDID. The applicability of each requirement depends on the device and rule.

Why it matters to a hospital

Capture the available identifiers during intake, service, and field action review. When a recall names affected lots or serials, an accurate record can reduce time spent searching. A UDI is useful for identification, but it does not replace service history, location, or ownership fields.

Common data-quality mistakes

Watch for truncated codes, transposed characters, a DI stored where the full UDI was expected, and accessories that have their own identifiers. Validate scanner output against the human-readable label before relying on a bulk import.

Practical decision aid

• Capture the human-readable code as well as a scan where practical, then verify how the inventory system splits the DI and any PI fields.
• Retain lot, serial, and expiration information when present. A DI identifies a model or version but may not isolate the specific units named in a recall.
• Check accessories independently when they carry separate identifiers. A main device record may not tell you which component is affected by a field action.