514 is good to go.
As we have learned, we do not assign a code for pleural effusion associated with congestive heart failure (CHF) if the pleural effusion is clinically insignificant.
Coding Clinic Third Quarter 1991 tells us that pleural effusion is an integral part of CHF. You should not assign it a code unless the physician says to do so (when it becomes "clinically significant"). The presence of a pleural effusion is inadequate to assign a code. The usual treatment for CHF is administration of diuretics, if the patient can tolerate them. If that is the only treatment, don't code it.
On the other hand, a patient with CHF can be admitted with pleural effusion that is so massive that respiratory symptoms are a mainstay of the presentation and the physician does a thoracentesis or insertion of a chest tube. In both of these circumstances, assign the pleural effusion with a secondary code. Never assign pleural effusion as the principal diagnosis in CHF cases.
Unless . . . and here's where physician documentation can be very helpful . . .
If a CHF patient has pleural effusion caused by something other than CHF, the circumstances of admission will determine the assignment of the code for pleural effusion.
When a CHF patient (or certainly any patient who does not have CHF) comes into the hospital with a pleural effusion, that pleural effusion can be due to renal failure (if he or she has renal failure), liver failure, or thyroid failure. The patient can also have pneumonia or a primary or secondary malignancy of the pleura. The physician has to tell you the origin of the pleural effusion.
In the case of these diseases, pleural effusion is not an integral part of the disease. You should assign and sequence a code based on the circumstances of admission, as explained earlier.
Under what circumstances might you sequence it first, you might ask.
Consider this scenario: A patient with known carcinoma of the kidneys or thyroid with massive pleural effusion, shortness of breath, and inability to carry on with activities of daily living is admitted. The physician draws off fluid or inserts a chest tube. Then, the circumstances of admission revolve around the presence of the malignant pleural effusion. You would sequence that first (ICD-9-CM 197.2). Or, if that diagnosis is first made on this admission and treatment directed toward it, sequence it first.
If the patient has a primary malignancy of the pleura (mesothelioma), then use the 163 series of codes, based on the physician's specification, if it involves the parietal or visceral pleura or if it is unspecified.
Before we go any further, you should know something about the two types of pleural effusions: transudate and exudate.
The transudate is a passive process where water leaks across membranes because of sick membranes, pressure excesses, or problems with the chemicals that hold the water where it belongs. Transudate fluids are usually clear and have low protein levels, high sugar, and low specific gravity and epithelial cells.
By contrast, an active process produces exudate fluids. In this process, water is pushed into the pleural space because of either inflammation or tumor. Exudates are cloudy or thick with high protein levels and low sugar. They have high specific gravity and white cells or tumor cells.
In our list above, the first five diseases are associated with transudative pleural effusions. The last two are exudative.
Most important, a pleural effusion associated with pneumonia can be transudative if it's caught early and it never turns exudative. On the other hand, if a patient with pneumonia comes in with an exudative pleural effusion, then it may alternatively be called "empyema." That call is up to the physician, who will find out which type of fluid it is by doing a tap that shows white cells and cloudiness). If the attending calls it an empyema, then it has a significant impact on the patient's stay, and antibiotic treatment or surgical intervention may be the driving force of treatment.
Where a transudative peripneumonic effusion will not affect the patient's length of stay or intravenous antibiotic treatment regimen, an exudative peripneumonic effusion may lead to two to six weeks of antibiotics and resection of a rib for long-term drainage.
Therefore, when a patient is admitted to the hospital with both pneumonia and an exudative pleural effusion that the doctor calls empyema, and the direction of treatment is toward the empyema, consider that for assignment as principal diagnosis.
Finally, you have to determine the origin of postmyocardial pleural effusion. If a patient goes into CHF after an MI, then there may be a related pleural effusion.
On the other hand, a patient may develop a pleural effusion after an acute MI, which represents Dressler's syndrome. The physician may refer to Dressler's syndrome as: post-MI fever, post-MI pericarditis, or post-MI pleural effusion.
These are all forms of Dressler's syndrome. This syndrome may appear as any one of these conditions or any combination of them. If you see one of these terms, check with the doctor to see whether it's a reference to Dressler's.