Distinguish between poisonings, adverse effects to code correctly in ICD-10-CM

A patient comes into the ED complaining of blurred vision, headache, dizziness, and numbness in her arms. The patient tells the physician she is currently taking prednisone for her arthritis. The physician determines the prednisone caused her symptoms.

 

Did the patient suffer from prednisone poisoning or an adverse effect of the medication?

 

The main detail to look for is whether the patient took the medication as prescribed, says Shannon E. McCall, RHIA, CCS, CCS-P, CPC, CPC-I, CEMC, CCDS, director of HIM and coding for HCPro, a division of BLR, in Danvers, Massachusetts.

 

An adverse effect can occur when a therapeutic or diagnostic medication is prescribed correctly and administered properly, but the patient suffers a physical reaction.

 

"When we say prescribed, it doesn't have to be a prescription medication," McCall says. "It could be something over the counter taken as directed on the package."

 

An adverse event occurs even though everything was done right. The physician prescribed the right drug in the right dose. The patient who took the drug was the patient it was prescribed for, and the patient took the drug in the right time frame.

 

Poisonings are considered the improper use of a medication/substance.

 

"They took the wrong substance, they took the wrong amount, they took it too often," McCall says.

 

A poisoning can occur with prescription drugs, over-the-counter medications, illegal drugs, or when drugs are taken with alcohol.

 

For the ED patient mentioned earlier, coders would look to see whether the patient took:

The physician documented that the medication was prescribed to this patient and that the patient took it as directed. Therefore, this patient suffered an adverse effect, not a poisoning.

 

Coders and CDI specialists need to make sure that they see the relationship between the prescribed medication and its effect as potential complications documented in the medical report, says Cheryl Ericson, MS, RN, CCDS, CDIP, CDI education director for HCPro.

 

"The documentation needs to specifically tell us the nature of the medication," Ericson says.

Patients are getting better about knowing what type of medication they take, and with electronic medical records, medications are now easier to identify, says Ericson.

 

"Remember, you can't assume from the electronic record or outpatient record, but you could use that as a prompting mechanism with a query," she adds.

 

Then coders and CDI specialists need to specify compliance with the provider's orders or the instructions of the over-the-counter medication. What is frequently missing from the documentation is whether the patient took the medicine as prescribed, Ericson says.

 

Next, identify any issues associated with obtaining or using the medications. Was it a prescription ­error? An administrator error? What kind of problems were there, and what was the unintended condition or outcome that occurred after the patient took the medication?

 

"That's really important for us to know and have so that we're able to accurately identify what kind of condition we're dealing with," Ericson says. "Our sequencing is dependent on whether we are dealing with an adverse effect versus a poisoning. So we want to make sure that we have the documentation to support that adequately." 

 

In ICD-9-CM, coders will use the Table of Drugs and Chemicals when coding a poisoning or adverse event. The table includes the following heading:

For the patient who suffered an adverse reaction to prednisone, coders would report the code for therapeutic use: E932.0 (adrenal cortical steroids).

 

The ICD-9-CM Official Guidelines for Coding and Reporting instruct coders to first report the adverse effect, such as tachycardia, delirium, gastrointestinal hemorrhaging, vomiting, hypokalemia, hepatitis, renal failure, or respiratory failure, followed by the E code.

 

Poisoning is coded if the medication use is described as one of the following:

For poisonings, first report a code from the 960-979 series listed in the poisoning column of the Table of Drugs and Chemicals to identify the poisoning, followed by the code(s) for the manifestation(s) of the poisoning. Also assign an E code to describe the circumstances of the poisoning (i.e., accidental, intentional, or undetermined). If the physician also documents a diagnosis of drug abuse or dependence on the substance, report an additional code for the abuse or dependence.

In ICD-9-CM, any poisoning that was intentional is classified as a suicide attempt.

 

Coding poisonings and adverse effects in ICD-10-CM is very similar, McCall says.

 

"When it comes to poisonings and adverse effects, those are codes that we pretty much always had in ICD-9," McCall says. "ICD-10 gives us a slightly different angle to take on the use of medications and substances."

 

In the ICD-10-CM Table of Drugs, coders will find the following headings:

When no intent for a poisoning is indicated, code to accidental. Only report undetermined intent when the provider documents in the record that he or she cannot determine the intent of the toxic effect.

 

The ICD-10-CM codes are combination codes that will include the substance and the intent, McCall says. No additional external cause codes are required for poisonings, toxic effects, adverse effects, and underdosing codes.

 

Underdosing is when a patient takes less of a medication than is prescribed or instructed, and it may be inadvertent or deliberate, McCall says.

 

Underdosing is becoming more common as patients take less of their medications for a variety of reasons, such as cost or side effects, says McCall. Underdosing can be intentional or unintentional.

The ICD-10-CM Official Guidelines for Coding and Reporting instruct coders to never report the codes for underdosing as a principal or a first-listed code.

 

"What we would list first is what condition the patient had that was exacerbated because he or she didn't take the medications as prescribed," McCall says.

 

For example, a patient is supposed to be taking cardiac medications, but takes less of the medication than prescribed. The patient ends up with decompensated heart failure or exacerbation of heart failure and is admitted to the hospital. Coders would report the systolic heart failure or the exacerbation first, then the underdosing code for the cardiac medication, McCall says.

 

Coders also need to report an accompanying code to identify how the underdosing occurred. If it was due to the patient, it could be either inadvertent or intentional. Coders also have these options to denote when the underdosing is related to medical care:

 

Patients may take a less of a medication than prescribed for several reasons.

 

First, the patient may be unable to afford the prescription, so he or she either cuts pills in half or skips doses. ICD-10-CM includes codes to specify the reason for patient noncompliance.

 

For example, if a patient underdoses on purpose because of financial hardship (he or she can't afford the medication), coders would report Z91.120 (patient's intentional underdosing of medication regimen due to financial hardship).

 

Patients may also underdose for other reasons, such as medication side effects. For those situations, report Z91.128 (patient's intentional underdosing of medication regimen for other reasons).

 

If the patient is unintentionally underdosing, coders will choose from two different codes. For example, a patient may suffer from age-related dementia and forget to take a prescribed medication. In those cases, report Z91.130 (patient's unintentional underdosing of medication regimen due to age-related debility).

 

For example, an elderly patient with dementia forgets to take minoxidil, a prescribed vasodilator for high blood pressure. This causes an unintended increase in blood pressure. Report I10 (hypertension) as the principal diagnosis. Then report T46.3X6A (underdosing of coronary vasodilators, initial encounter), followed by Z91.130 and a code to denote dementia.

 

If the patient unintentionally underdoses for another reason, report Z91.138 (patient's unintentional underdosing of medication regimen for other reason).

 

For both intentional and unintentional underdosing, ICD-10-CM instructs coders to code first underdosing of medication (T36-T50) with fifth or sixth character 6.

 

In addition, coders will find an Excludes1 note for both types of underdosing:

In ICD-10-CM, an Excludes1 note is a pure excludes note. The two conditions are mutually exclusive and cannot be reported together, McCall says.

 

Coders need to add a seventh character to poisoning, adverse effect, and underdosing codes. They will choose from:

The ICD-10-CM Official Guidelines for Coding and Reporting instruct coders to report the adverse effect first (the manifestation, symptom, or the adverse effect condition) followed by the appropriate code for the adverse effect of the drug (T36-T50).

 

For example, if the ED patient suffering from the adverse effects of prednisone came in, coders would first report all of the adverse effects before reporting T38.0X4- (adverse effect of glucocorticoids and synthetic analogues).

 

However, if the patient was poisoned by prednisone, coders would report the poisoning code first, McCall says. Use additional code(s) for all manifestations of poisonings.

 

If the physician also diagnoses abuse or dependence of the substance, the abuse or dependence is assigned as an additional code, McCall adds.

 

For example, a patient improperly took a medication that he was prescribed and is in acute respiratory failure. The respiratory failure is still going to be an additional diagnosis, not the principal diagnosis, McCall says. "The poisoning code that identifies the substance and the intent of how the poisoning occurred will be the principal diagnosis."