ED Coding and Reimbursement Alert

The key to receiving proper reimbursement for medication poisoning depends entirely on whether the patient took a drug correctly or inappropriately. The ED physician must first determine if the patient suffers from a poisoning or an adverse reaction to a drug.
 
An adverse effect occurs when a medication is properly administered and correctly prescribed and the patient has an ill effect. A poisoning should be coded if drugs, medications or other substances that are not used in accordance with a physician's instruction cause the reaction. 

Reporting Poisoning

 
The Table of Drugs and Chemicals, which is after the alphabetical listing in ICD9 Codes, is the tool to use for accurately coding poisonings. It contains an extensive list of drugs, industrial solvents, corrosives, gases, noxious plants, pesticides and other toxic agents. The table is structured to identify the substance, the corresponding poisoning code and the circumstances of the poisoning or adverse effect. This last category uses E codes (external cause) to cover accident, therapeutic use, suicide attempt, assault and undetermined (when the intent of the poisoning or injury cannot be determined as intentional or accidental).
 
Note: 1) Many carriers do not require that ED physicians assign an E code when reporting a poisoning. However, you should use these external-cause codes even if the payer considers it optional because they help clarify the incident and provide accurate statistics. 2) Do not confuse E codes used to describe the external cause in poisoning cases with the therapeutic E codes used when a patient's illness is caused by an adverse reaction. Therapeutic E codes should not be assigned in poisoning cases.
 
Terms normally associated with a drug poisoning include overdose, poisoning, wrong substance given or taken, and intoxication. Examples of how poisonings occur include an overdose taken to attempt suicide, the wrong dosage is given or taken, a medication (prescription or nonprescription) is combined with alcohol, a prescription drug is taken with an over-the-counter drug, or an illegal drug is taken or there is intoxication (other than a cumulative effect).
 
You'll need at least three codes to correctly report a poisoning in just about every poisoning case. And the way you sequence the codes depends on the intent and effect of the poisoning.
 
Identify the drug that has caused the poisoning as it is described in the Table of Drugs and Chemicals. The first code to list will be from the poisoning column and identifies the drug or chemical. The second code indicates the condition (e.g., coma or stupor) resulting from the poisoning. The third code (E code) identifies the cause of the poisoning as an accident, a suicide attempt, an assault or an undetermined cause.
 
If the patient has taken the wrong drug or an incorrect dosage or has combined incompatible substances, report the poisoning code first for the drug taken followed by symptom codes. Then choose the appropriate E code from the table to indicate the external cause of the poisoning, which might include assault, accidental ingestion or suicide attempt.
 
If the ill effect is caused by an adverse reaction, code symptoms first. Then, referring to the table, locate the drug with the E code that indicates "therapeutic use."
 
Finally, code late effects -- those that continue to affect the patient after the acute phase of the reaction has passed. Code the residual or remaining effect first and then assign the late-effect code, 909.5 (late effect of adverse effect of drug, medical or biological substance) or 909.0 (late effect of poisoning due to drug, medicinal or biological substance). Code the drug effect the same as the immediate drug reaction, i.e., signs and symptoms for adverse reactions and poisoning codes from the table in poisoning cases.
 
Coding an Overdose

 
Michael Granovsky MD, CFO of Greater Washington Emergency Physicians, a five-physician group staffing an ED in Maryland, says one of the most common poisoning cases is overdose. He provides this case of an overdose victim and how to code the procedures.
 
Case: A 23-year-old female is admitted to the ED after taking 20 Paxil, 10 Ativan and drinking alcohol (six to seven cocktails) in an apparent suicide attempt. She was lethargic, had low blood pressure and was not breathing well. The physician performed a stomach lavage and ordered an EKG because the patient had difficulty breathing. The ED physician read the EKG and performed a complete history and physical exam. Because the patient was too lethargic to participate, the physician spoke with the family and asked them to go through her belongings to find the pill bottles.
 
Coding the Procedures: To code this case, use 91105 (gastric intubation) for the gastric lavage. However, if the ED physician did not perform the lavage, the procedure can only be reported by the facility and itemized on the hospital facility bill. The ED physician can bill for the EKG interpretation using 93010 (electrocardiogram; interpretation and report only) if it is well documented.
 
Because the patient was unable to provide a history, the E/M level would be determined primarily by the level of the ED physician's medical decision-making (MDM). The acuity caveat allows the physician to score a higher level of service (99285) if the patient's condition prohibits obtaining a comprehensive history and physical examination. The E/M level would be determined by the treatment provided, exclusive of the EKG and gastric lavage. This case would typically be billed with 99284 (emergency department visit for the evaluation and management of a patient, which requires these three key components: a detailed history, a detailed examination, and medical decision-making of moderate complexity) or 99285 (... a comprehensive history, a comprehensive examination, and medical decision-making of high complexity). It could also possibly be critical care (99291) if the service is consistent with those guidelines.
 
Note: For more information on critical care, see the June 2001 ED Coding Alert.
 
Coding the Circumstances and the Poison: "Because the ED physician noted that the patient did not take the medications as prescribed, you should automatically look at poisoning instead of adverse effects," says Kia R. Earp, CCS, coding specialist for Health Information Services at Brigham and Women's Hospital in Boston.
 
Referring to the Table of Drugs and Chemicals, assign the correct codes based on the type of medication involved. Paxil is an antidepressant, Ativan is a benzodiazepine, and alcohol is an ethyl beverage. Therefore, the diagnosis coding would be as follows:

969.0 -- poisoning, antidepressants (Paxil)

969.4 -- poisoning, benzodiazepine (Ativan)
980.0 -- toxic effect, ethyl alcohol
E950.3 -- suicide attempt, same code is used for both the Ativan and the Paxil
E950.9 -- suicide attempt, alcohol ingestion.

 
Also assign late-effect codes if applicable. For example, once the lethargy and poor breathing have been corrected, the overdose victim might continue to suffer from a moderate headache. When this occurs, assign a late-effect code. The correct coding sequence in this instance is first to list the residual or remaining effect  (i.e., headache -- 784.0) and, second, assign the late-effect code 909.0.

Adverse Effects: Use Therapeutic E Codes

 
Adverse effects vary with individual patients, including factors such as genetics, disease state, age and sex. These factors can influence accumulative effects (drug toxicity), allergic reactions, hypersensitivity, interaction between prescribed drugs, side effects and idiosyncratic, synergistic and paradoxical effects. Chronic effects of a drug taken over a long time -- and still being taken -- are also coded as adverse reactions.
 
To code an adverse effect, first identify it -- e.g., tachycardia, hallucinations, vomiting, respiratory failure or gastritis. List the code for the symptom(s) first. Next, identify the drug in the Table of Drugs and Chemicals. Find the corresponding E code under the column "Therapeutic Use" and list it as an additional code on the claim.
 
Scenario: A 32-year-old male patient presents to the ED with a rash that appeared days after taking his newly prescribed Paxil. He was being treated for depression and had taken his medication according to the doctor's instructions. In this case, the patient had an adverse reaction to the prescribed medication.
 
"At this point the ED physician would recommend that the patient discontinue the Paxil and follow up with the original treating physician for a different antidepressant," Earp says. "This would most likely be coded a level-three E/M unless medications were given, and then it might qualify as level four."
 
Coding: Use the therapeutic E codes as follows:
 
693.0 -- dermatitis
E939.0 -- therapeutic use of antidepressants (Paxil).