acute renal failure--a potential RAC risk?

[syopp]

Our Clinical Documentation Improvement Team would like your input on an issue we recently discussed. We currently use J.A. Thomas and Associates for our CDMP. Their guidelines for acute renal failure state "a relative creatine increase of more than 0.3 mg/dl over a baseline below 2mg/dl along with other clinical indicators such as hyperkalemia, oliguria, and anuria can indicate acute renal failure. These are the guidelines our Clinical Documentation Improvement Specialists are using when querying the physician for acute renal failure.

However, Interqual guidelines are much more stringent. They state in the Critical Medical chapter: severity of illness (SOI) is Oliguria and BUN >45 or Oliguria and Creatine > 3.0, then in the Genitourinary chapter: SOI is BUN >100 or Creatine > 5.0 meets criteria for inpatient admission with these as the principal diagnosis.

We were wondering if we would be at risk for the RAC auditors possibly using the more stringent Interqual criteria and therefore disqualifying what we are currently using to diagnose acute renal failure.      

Thanks!