Pulmonology Coding Alert

Question: Do different codes exist for patients admitted to the hospital with respiratory failure that are due and not due to underlying respiratory conditions?
Ohio Subscriber
 Answer: There are three codes for acute respiratory failure. Code 518.81 is for acute respiratory failure, but excludes acute and chronic respiratory failure, acute respiratory distress, chronic respiratory failure, respiratory arrest and respiratory failure for a newborn. Code 518.83 is for chronic respiratory failure, while 518.84 is for acute and chronic respiratory failure.  
A patient admitted to the hospital for acute respiratory failure may have underlying respiratory conditions. Individuals with existing pulmonary disease may already have consistently altered carbon dioxide and oxygen levels. For these individuals, only a marked variation in these levels would indicate acute failure. When the individual is admitted to the hospital, 518.81 is reported with the admission service (99221-99223). 
However, a patient with end-stage emphysema who has consistently altered carbon dioxide and oxygen levels and is oxygen dependent, with diagnosis of chronic respiratory failure, may be admitted to the hospital for an exacerbation of emphysema (shortness of breath, wheezing, etc.). This exacerbation may have severely deteriorated the patients already compromised condition, causing acute failure. In this case, 518.84 would be reported.
It may be best to provide more than one diagnosis code to accurately reflect the patients illness and co-existing condition(s). In the emphysema scenario above, 518.84 and 492.8 (other emphysema) could be used together. This will convey acuity and severity of an illness or injury. Providing multiple ICD-9 codes to an insurer for one service will not increase your reimbursement but will help ensure medical necessity for which payment can be made.