Pulmonology Coding Alert

Pulmonologists should code the treatment of adverse effects from medication based on whether the correct medicine was taken, whether it was taken in the recommended dosage, and whether it was combined with incompatible substances. These problems can occur due to patients misreading prescription labels, or miscommunication between specialists regarding the full list of drugs that the pulmonary patient is taking.

We occasionally see patients with adverse reactions to medications, says Diana Selby, RN, a nurse at Pulmonary Associates, a three-pulmonologist practice in Owensboro, Ky. Most of the problems are in connection with the inhalers, especially albuterol, because its prescribed very often, says Selby. The problem often involves the inert ingredients in the inhalant. For example, we have one patient who is allergic to corn products, which can be used as part of the propellant in some of the inhalers.

If a patient overuses an albuterol inhaler, he or she may experience trembling, high blood pressure, or fast or irregular heartbeats. An actual overdose may leave a patient gasping for breath. Other drugs, such as Atrovent, may cause problems when used by patients with allergies to peanuts or soy. The following factors also add to medication problems:

most patients take prescription medication from
other physicians for other problems and dont always tell
their pulmonologists about them;
patients may be taking megadoses of herbs and vitamins,
but dont report them because they dont think of them as
medication;
elderly patients may become confused when trying to
juggle their medicine regimens; and
patients may not report potential problem symptoms.

Determining the Cause of Adverse Reactions

A patient with asthma (ICD-9 493.00 -ICD-9 493.91 ) receives a prescription for theophylline. The patient fills the prescription and takes her first dose that afternoon. The next day, she phones the pulmonologist, stating that she is experiencing nausea, nervousness, an increased heart rate and a severe headache. The pulmonologist asks the patient to come back to the office. He examines her for 10 minutes and determines that the patient may be experiencing symptoms related to the theophylline.

The case seems fairly straightforward until you consider all of the diagnosis coding scenarios it represents. Reviewing the ICD-9 Table of Drugs and Chemicals causes more confusion. The table has six column heads poisoning, accident, therapeutic use, suicide attempt, assault and undetermined. There is no single, simple answer on how to code the problem. A professional coder needs to consider the specific clinical situation and carefully review the pulmonologists notes. To ensure proper reimbursement, follow these four steps:

1. Determine whether the drug was taken properly. Coders must be able to determine whether the patient took the medication correctly, according to Kathryn Cianciolo, MA, RRA, CCS, CCS-P, chair of the Society for Clinical Coding in Waukesha, Wis., and an independent medical practice management consultant. This is key to determining whether to code a poisoning or an adverse reaction.

The American Hospital Association (AHA) and ICD-9 clearly distinguish between the two, Cianciolo says, and specify that an adverse reaction to a prescribed drug should not be coded as a poisoning unless the medication was taken contrary to the physicians instructions.

2. For an adverse reaction, code the symptoms first. If the patients condition is attributed to an adverse reaction, coders should first assign the diagnosis code that describes the manifestation or nature of the adverse reaction, Cianciolo advises.

For example, in the case of the patient suffering from nausea, nervousness, increased heart rate and severe headache, coding the symptoms would involve 787.02 (nausea), 799.2 (nervousness), 785.0 (tachycardia; unspecified) and 784.0 (headache, unspecified).

Then the coder would refer to the ICD-9 Table of Drugs and Chemicals and locate theophylline ethylenediamine. Because the drug was prescribed and taken properly, the coder would assign E945.7 for therapeutic use.

Note: The codes listed in the table are for reference only; each code in the ICD-9 table should be verified in the tabular list section of the manuals directory before submitting a claim.

3. For poisoning, report poisoning codes first. If the patient has taken the wrong drug, the wrong dosage or combined incompatible substances, the coder should report the poisoning code for the drug taken followed by symptom codes. If the patient in the example had taken twice the prescribed dosage of theophylline, the coder would refer to the Table of Drugs and Chemicals, find theophylline ethylenediamine, and report the code that appears in the Poisoning column 975.7 (poisoning by agents primarily acting on the smooth and skeletal muscles and respiratory system, antiasthmatics). In addition, the coder would assign codes for the signs and symptoms the patient exhibited, as listed in step 2.

Finally, the coder would choose the appropriate E code to indicate the external cause of the poisoning, which might include assault, accidental ingestion or suicide attempt. In the example given, the inexperienced theophylline patient inadvertently may have taken the wrong dosage, so the coder would assign E858.6 (accidental poisoning by agents primarily acting on the smooth and skeletal muscles and respiratory system).

According to Jeri Leong, RN, CPC, an independent medical practice management consultant and certified coding instructor in Honolulu, many carriers do not require that physicians assign an E code when reporting a poisoning. But I encourage all coders to use these E codes for external causes even if the payer considers it optional, she says. These codes help to clarify the incident and provide accurate statistics.


4. Code late effects and immediate reaction. Cianciolo notes that late effects the problems that continue to affect the patient after the acute phase of the reaction has passed also need to be reported. For instance, once the nausea, nervousness and increased heart rate have been corrected, the asthmatic patient may continue to suffer from a moderate headache. When this occurs, the coder should assign a late effect code first. The correct sequence in this event would be:

code the residual or remaining effect first (headache 784.0);
assign the late effect code 909.5 (late effect of
adverse effect of drug, medicinal or biological
substance) or 909.0 (late effect of poisoning due
to drug, medicinal, or biological substance); and
code the drug effect the same as with the immediate drug
reaction (i.e., signs and symptoms for adverse
reactions, and poisoning codes from the Table of Drugs
and Chemicals in poisoning cases).

How to Code Drug Interactions

Suppose the pulmonologist examining the patient with adverse reactions to theophylline orders a comprehensive metabolic panel (80053), which is within normal limits. The pulmonologist again asks the patient whether she could have taken a larger than prescribed dosage or whether she took any other medications with the theophylline. The patient responds that she didnt take anything, except for her usual exercise supplement, a product that the pulmonologist recognizes as one containing ephedrine. The pulmonologist determines that the ephedrine, which can increase the effects of theophylline, may have caused a reaction, and reminds the patient that she shouldnt take diet or exercise supplements with her theophylline.

The visit described above for effects from theophylline should be coded as an adverse reaction, using 787.02 (nausea), 799.2 (nervousness), and 785.0 (tachycardia; unspecified), and 784.0 (headache, unspecified) with E945.7 for the theophylline (adverse reaction; antiasthmatics) and E941.2 (adverse reaction; sympathomimetics) for the ephedrine.