Code Chemo Complications Quickly and Correctly
Not all negative reactions to antineoplastic medications should be coded as adverse effects. The scenario is common in oncologists’ offices around the country: A patient comes to see a provider complaining of nausea, fatigue, gastrointestinal issues or one of a number of other adverse effects that are a direct result of the chemotherapy regimen the provider has put in place to treat the patient’s cancer. To justify medical necessity for the ensuing evaluation and management (E/M) encounter, you correctly turn to the Table of Drugs and Chemicals in your ICD-10-CM book and find the chemotherapy drug that the patient has been taking. But which one of the T36-T50 (Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances) codes featured in the table should you use? Each one describes one of three different adverse effects: poisoning, underdosing, and a general category simply called “adverse effect.” Worse, poisoning can be accidental, intentional, due to assault, or undetermined. You need a foolproof method to narrow down your choices and choose the correct code quickly and easily. Well, look no further. Here it is. First, Understand Adverse Effect The term “adverse effect” has a specific meaning in ICD-10-CM coding. It is reserved solely for patients who have taken “a drug that has been correctly prescribed and properly administered.” Guideline I.C.19.e.5.a tells you “the code for the drug should have a 5th or 6th character ‘5.’” Additionally, the guideline gives you examples of the kind of adverse effects your provider may have to manage in a patient: “tachycardia, delirium, gastrointestinal hemorrhaging, vomiting, hypokalemia, hepatitis, renal failure, or respiratory failure.” In E/M encounters where your provider treats a patient for an adverse effect to a chemotherapy drug, you will code the adverse effect being treated at the encounter first, followed by a code from T36-T50. Example: Your provider has been treating a testicular cancer patient with cisplatin. The patient has been experiencing nausea and vomiting and informs the doctor they have attended all their infusion appointments. The provider confirms the patient has been receiving the correct dosage at those appointments. Based on that information, you will report the following ICD-10-CM codes: Assuming this is the patient’s first encounter with the provider for this problem, you’ll also add 7th character “A” (initial encounter) to T45.1X5-. Remember: There are a handful of combination codes that describe conditions caused by chemotherapy that you could possibly use as reasons for an encounter, including: Then Understand Underdosing Like adverse effect, underdosing also has a specific meaning in ICD-10-CM coding as stated in guideline I.C.19.e.5.c. Specifically, “Underdosing refers to taking less of a medication than is prescribed by a provider or a manufacturer’s instruction.” The guideline also notes that “discontinuing the use of a prescribed medication on the patient’s own initiative (not directed by the patient’s provider) is also classified as an underdosing.” The guideline specifies that a code from T36-T50 cannot be used as a principal or first-listed code in this situation. Instead, if the underdosing results in “a relapse or exacerbation of the medical condition for which the drug is prescribed because of the reduction in dose, then the medical condition itself should be coded.” Underdosing encounters will also require you to use a third ICD-10-CM code for noncompliance or complication of care to indicate intent, if known. These include: Intentional reasons include financial hardship (Z91.120 or Z91.A41), while unintentional reasons include age-related debility (Z91.130). Example: During an E/M encounter, the oncologist discovers a patient with multiple myeloma has been taking less cyclophosphamide than precribe. The patient tells the doctor that they have been intentionally cutting back on the drug because of financial difficulties. Consequently, the patient’s condition has begun to deteriorate. In this situation, you’ll code the patient’s condition from C90.- (Multiple myeloma and malignant plasma cell neoplasms); likely C90.02 (Multiple myeloma in relapse) first, followed by T45.1X6- (Underdosing of antineoplastic and immunosuppressive drugs), Z91.120, and Y63.6. Last, Understand Poisoning Here, again, the term has a specific meaning in ICD-10-CM, which specifies four different types of poisoning: Additionally, you will need to determine whether the poisoning is intentional, accidental, or if the intention cannot be determined. Example: In our cisplatin example above, suppose the patient reports to the oncologist complaining of feeling sicker than usual after their most recent infusion appointment. The provider checks the medical record and determines the dosage of the drug administered at the patient’s last appointment was incorrect, and the patient had received a higher-than-prescribed dose of the drug in error. In this situation, you would use T45.1X1- (Poisoning by antineoplastic and immunosuppressive drugs, accidental (unintentional)), this time as the principal (or first-listed) code for the encounter. ICD-10-CM then tells you to code “all manifestations of poisoning” and “abuse or dependence of the substance” if applicable, which, in this case, would not be necessary. Bruce Pegg, BA, MA, CPC, CFPC, Managing Editor, AAPC
