Q&A: Pleural effusion as integral to respiratory failure

Q: We recently had a situation where a 72 year old was admitted with large pleural effusion, fever, elevated white blood cell count, and a left shift. The provider also documented acute respiratory failure.

Although I see the treatment directed at the pleural effusion, I was taught that respiratory failure is always due to another condition. In the absence of any documentation in the scenario about any other respiratory disorder, I would be looking for a link between the pleural effusion and the respiratory failure. My question is whether it is appropriate to submit a query to ask the provider for the link. Furthermore, if he does provide a link, I’m wondering if the principal diagnosis would become acute respiratory failure, taking the DRG to 189.

A: The sequencing of acute respiratory failure is a very complex coding issue.  Let’s try to break it down.

First, is the acute respiratory failure a reportable diagnosis? Does it meet the criteria of a principal diagnosis or a secondary diagnosis? Was it evaluated, treated, and monitored? Did it require increased nursing care, or increased the length of stay? If the acute respiratory failure is integral to the pleural effusion then it would not be a reportable diagnosis; however, I think most providers would agree that it is not integral as not all patients with a pleural effusion experience acute respiratory failure.

Acute respiratory failure is one of those diagnoses where an auditor would expect to see treatment to support the validity of the diagnosis, so look for supportive documentation beyond monitoring, increased nursing care, etc.  Acute respiratory failure will always require treatment unless the patient is a DNR/comfort measures only. There are many different thresholds as to what constitutes acute respiratory failure versus hypoxia or acute respiratory insufficiency, for example. Capturing the type of treatment is as important as capturing the diagnosis.

Although the patient does not have to be receiving mechanical ventilation to support reporting acute respiratory failure, most physicians and auditors would agree that the patient should receive a minimum of 40% oxygen, which is equal to at least five liters of oxygen via nasal cannula. Best practice is for your organization to have a standard definition with specified clinical indicators to support consistent reporting of acute respiratory failure.

Assuming the clinical indicators support acute respiratory failure, the timing of the diagnosis is important. Was the acute respiratory failure present on admission or did it occur during the admission? If it occurred during the admission, then it could not be the principal diagnosis even if it was linked to pleural effusion.

In order to consider acute respiratory failure as the principal diagnosis it would have to be present at the time of admission rather than occurring subsequently. Acute respiratory failure is not clarified “after study” as a patient either has acute respiratory failure or they do not. The cause of the acute respiratory failure can be identified “after study” and may impact treatment, because itcannot be “cured” unless the underlying causative condition is also treated. However, just because the underlying condition is also treated does not mean the patient was admitted for the underlying condition.

The Official Guidelines for Coding and Reporting supersede recommendations by the AHA’s Coding Clinic for ICD-9-CM. According to Official Guidelines for Coding and Reporting I.C.8.c.:

“Acute respiratory failure as principal diagnosis: Acute respiratory failure, may be assigned as a principal diagnosis when it is the condition established after study to be chiefly responsible for occasioning the admission to the hospital, and the selection is supported by the Alphabetic Index and Tabular List. However, chapter-specific coding guidelines (such as obstetrics, poisoning, HIV, newborn) that provide sequencing direction take precedence.

“Acute respiratory failure as secondary diagnosis: Respiratory failure may be listed as a secondary diagnosis if it occurs after admission, or if it is present on admission, but does not meet the definition of principal diagnosis.

“Sequencing of acute respiratory failure and another acute condition: When a patient is admitted with respiratory failure and another acute condition, (e.g., myocardial infarction, cerebrovascular accident, aspiration pneumonia), the principal diagnosis will not be the same in every situation. This applies whether the other acute condition is a respiratory or non-respiratory condition. Selection of the principal diagnosis will be dependent on the circumstances of admission. If both the respiratory failure and the other acute condition are equally responsible for occasioning the admission to the hospital, and there are no chapter-specific sequencing rules, the guideline regarding two or more diagnoses that equally meet the definition for principal diagnosis (Section II, C.) may be applied in these situations. If the documentation is not clear as to whether acute respiratory failure and another condition are equally responsible for occasioning the admission, query the provider for clarification.”

To my knowledge there is no chapter specific guideline regarding pleural effusion and acute respiratory failure, so even if the pleural effusion is the cause of the acute respiratory failure, it does not mean the principal diagnosis would be the pleural effusion with acute respiratory failure as a secondary diagnosis.   As such, we must consider if both pleural effusion and acute respiratory failure are equally responsible for occasioning the admission.

The guideline does not state if two or more conditions are present on admission, pick the best one, it states “two or more diagnoses equally meet the definition for principal diagnosis.”

So let’s look at Official Guidelines for Coding and Reporting Section II, C:

“Two or more diagnoses that equally meet the definition for principal diagnosis: In the unusual instance when two or more diagnoses equally meet the criteria for principal diagnosis as determined by the circumstances of admission, diagnostic workup and/or therapy provided, and the Alphabetic Index, Tabular List, or another coding guidelines does not provide sequencing direction, any one of the diagnoses may be sequenced first.”

What would you consider an “unusual instance?” This guideline is used liberally by coders and CDI professionals alike, but the guideline itself, states, “in the unusual instance” and continues by addressing the circumstances of the admission . . . so in order to accurately assign the principal diagnosis if choosing between pleural effusion and acute respiratory failure one would ask:

• Do all patients with pleural effusion require inpatient hospital care?
• At what point did this patient with a pleural effusion require inpatient care?
• Was it on initial presentation for this condition?
• Do all patients with acute respiratory failure require inpatient hospital care?
• At what point did this patient with acute respiratory failure require inpatient care?
• At what point is this patient likely to be discharged?

If the answer is when the patient’s respiratory status is stable, then it would support acute respiratory failure as the principal diagnosis.

The good news is that as a CDI specialist we don’t have to choose which is the principal diagnosis because the coding guideline also states:  “If the documentation is not clear as to whether acute respiratory failure and another condition are equally responsible for occasioning the admission, query the provider for clarification.”

My recommendation is that whenever there is a disagreement regarding the principal diagnosis, query the provider for clarification. Here is an example of how that query may be asked:

Dear Dr. Respiratory Failure;

Mr. X was admitted with the diagnoses of pleural effusion and acute respiratory failure. Can you please clarify which of these two conditions occasioned the admission to the hospital in the next progress note:

• The acute respiratory failure
• The pleural effusion
• Unable to determine
• Other: _________

These types of queries will be most effective if you educate your providers about the inpatient perspective payment system and the significance of the principal diagnosis. Additionally, you may want to work collaboratively with your case management/utilization review department to educate providers regarding the documentation needed to support inpatient medical necessity.

Editor’s Note: Cheryl Ericson, MS, RN, CCDS, CDIP, AHIMA Approved ICD-10-CM/PCS Trainer, CDI Education Director for HCPro Inc., answered this question. Contact her at cericson@hcpro.com. For information regarding CDI Boot Camps offered by HCPro visit www.hcprobootcamps.com/courses/10040/overview. This article was originally published on the ACDIS Blog.