Q: The patient ingested Draino and Tilex and has a mild caustic injury to the take-off of the LUL and LLL of the respiratory system. Patient also has a grade II injury (friable) to the esophagus and grade III injury (deep ulcers) to the stomach and pylorus. How should these injuries be coded and what is the ISS?

A: AIS 98: Bronchus distal to main stem, partial thickness injury – 440206.2
ISS = 13

AIS 2005: Bronchus distal to main stem, partial thickness injury – 440206.2
Esophagus partial thickness ingestion injury – 440807.3
Stomach ulcers (also a partial thickness ingestion injury) – 5444153
ISS = 18
Note that the codes change slightly in AIS 2005 because we have added descriptors for caustic ingestion injuries. In this case it also increases the ISS.