Critical Care FAQ Critical Care FAQ FAQ1.
Some physicians use critical-care codes frequently.
The CPT book allows you to bill for the first hour of critical-care if the documented time of service is between 30 and 74 minutes. For a complete description of critical-care service and what is bundled into that code, consult the CPT Book. A minimal time threshold of at least 30 minutes for the first hour of critical care is required to qualify for use of CPT code 99291. The time need not be continuous. For Medicare patients, HCFA notes that neither patient care time provided by a resident in the absence of the teaching physician nor time spent teaching can contribute to critical care time.