Q&A: Respiratory failure in a drug overdose

Many of our providers document “respiratory failure,” when, in fact, they are using the ventilator to help with the work of breathing in order to prevent the patient from actually progressing to acute respiratory failure. By using the ventilator, they are attempting to protect the airway due to encephalopathy, combative nature, or altered mental status.

 

A:  First identify any supportive clinical indicators for a diagnosis of acute respiratory failure.

Respiratory failure is traditionally defined as the inability to perform the lung’s function of gas exchange, or the transfer of oxygen and carbon dioxide within the blood. Respiratory failure can be a failure to oxygenate the tissues or a failure of ventilation, meaning a failure or impairment of airflow in and out of the lungs. It is frequently a combination of the two mechanisms.

 

Often, patients admitted for poisoning, overdose, or trauma will exhibit clinical indicators for respiratory failure, and the documentation will state “intubated for airway protection.” If the patient is unable to maintain an open airway and perform ventilation, that is considered respiratory failure.

 

With this in mind, the first step in reviewing the record is to determine if the intubation/ventilation is performed to truly protect the airway, or if the airway is already impairing gas exchange. The record must be reviewed for clinical indicators to support an acute respiratory failure that includes oxygen saturations, blood gas, respiratory rate, respiratory distress, etc.

 

Once the patient is intubated, a good clue as to the presence or absence of respiratory failure is a review of treatment related to the ventilator. If the patient requires frequent vent changes or intervention, this likely supports an acute respiratory failure.

 

If the reason for intubation is unclear, a query is likely needed. If, after this examination, you conclude there was no respiratory failure, then the diagnosis should not be coded.

 

AHA Coding Clinic, Third Quarter 2012, p. 21, asks the question:

 

“QUESTION: A patient presents to the ED due to an overdose of Ambien and is intubated and placed on mechanical ventilation. The attending physician admits the patient to the ICU and comments that the patient was intubated for airway protection because of the overdose. There was no documentation of respiratory failure and the patient was weaned from the ventilator the next day. Can the coder assume the patient was in respiratory failure, based on the fact the patient was intubated and placed on mechanical ventilation for airway protection?

 

“ANSWER: Do not assign the code for acute respiratory failure, simply because the patient was intubated and received ventilator support. Documentation of intubation and mechanical ventilation is not enough to support assignment of a code for respiratory failure. The condition being treated needs to be clearly documented by the provider.”

 

So, long story short, if acute respiratory failure is documented in the situation you describe above, and there are no clinical indicators for the respiratory failure, I would query the provider to clarify the most appropriate diagnosis. If the patient is intubated to only protect an airway from potential compromise, that is not a respiratory failure and should not be diagnosed or coded as such.

 

One suggestion is to develop an organizational definition of both acute and chronic respiratory failure that your medical staff can use in these situations. I would suggest working with your physician advisor, intensivist, or pulmonologist to define the parameters. The diagnostic criteria would be used by CDI specialists and coders to identify a need for query. Providers can use the criteria to differentiate between the true reason for intubation.