ICD-10: 26 Tips You Absolutely Want to Know!

Betsy Nicoletti, MS


September 23, 2015

In This Article

Coding Changes Affect All Aspects of Treatment


It is surprising that in a coding system that has grown so large, there are still thousands of unspecified codes. Coders say to avoid them.

But not all unspecified codes are created equal. Do avoid the unspecified codes at the end of a category, such as H10.9, unspecified type of conjunctivitis. Do avoid a code that has the word unspecified in the description twice such as S93.409A, sprain of an unspecified ligament of unspecified ankle, initial encounter.

But sometimes, the clinician can't select a more specific code based on the available information. A patient seen in the office with pneumonia will be correctly assigned J18.9. pneumonia, unspecified organism. Yes, there are more specific diagnosis codes for pneumonia when the organism is known, but in the office setting the organism is rarely known, and the most accurate code is pneumonia from an unknown organism.

Not all unspecified codes are created equal.

V00-Y99 External Causes of Morbidity

The external cause codes in category V00-Y99 got all the press in the discussion of ICD-10. Walking into a lamp post, again, or being on fire while on water skis—these proved irresistible. However, reporting external cause codes remains optional in ICD-10, as it was in ICD-9. Some payers require practices to report these codes to tell them the cause of the injury or accident. In ICD-10, the types of accidents are mindlessly detailed, and practices won't typically have sufficient information to code with the level of detail possible. If reporting external cause codes (V00-Y84), they also require a seventh character extender. External cause codes are not used with codes listed in the drugs and chemicals chart, such as adverse effects of anticoagulant drugs, in categories T36-T50.

External cause codes are optional, per ICD-10, but your payer may require them.

With and Without

ICD-9 had plenty of codes describing the symptoms or manifestations of the condition with the word "with." ICD-10 doubles down on that.

There are many combination codes to describe both the condition and the symptoms. The uncomplicated condition is described as uncomplicated or without the symptoms such as "without angina." There are many more that describe the specific manifestation, "with acute exacerbation," "with hallucinations," or "with bleeding." If the patient has a manifestation of their disease, avoid using an unspecified code and avoid using a code with the word "uncomplicated." These codes don't communicate the severity of the patient's disease to the payer or explain higher costs, utilization, readmissions.

If there is an ICD-10 code that describes a manifestation of the patient's condition, use it.

X-ray Abnormalities and Other Abnormal Diagnostic Test Results

Codes for abnormal findings on diagnostic tests are found in Chapter 18, "Symptoms, signs, and abnormal clinical and laboratory findings, not elsewhere classified." They are category codes R70-R94.

For example, R70-79 is abnormal findings on examination of blood, without diagnosis. R73.0-abnormal glucose has an "excludes1" note that includes diabetes. That is, if the patient has diabetes, don't report abnormal glucose as the diagnosis. Use the codes in this section when there is an abnormal diagnostic finding, but the patient hasn't been assigned a definitive diagnosis that explains the finding.

Abnormal diagnostic test results are reported with codes from the signs and symptoms chapter.

Y92-Y99 Activity and Occurrence Codes

In addition to the external cause codes, there are three categories of codes that further describe how and where an accident occurred. These are also optional—there is no mandate to use them.

Y92 describes where the accident happened, and these are as specific as the rest of ICD-10. Was the patient injured in the kitchen in a prison, in a swimming pool of a nursing home—well, you get the idea. Y93 is the activity code, and it is often redundant with the external cause codes. This code describes for a second time what the patient was doing when the accident occurred. Y99 is the external causes status; is the patient a civilian, in the military, or doing volunteer activity? Do not report a seventh character extender with these occurrence and activity codes.

Hold off on using these codes until you hear otherwise from your payers.

Zapped by a Zebra

Disappointingly, there is no external cause code for an injury caused by a zebra. With 70,000 codes, couldn't they spare one for kicked by a zebra? Of course, even if there were an external cause code for injury by zebra, it would not start with the letter Z.

The final chapter in ICD-10 is called "Factors influencing health status and contact with health services." Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed.

These are equivalent to the V codes in ICD-9. This chapter includes personal and family history of medical conditions, examination codes, and aftercare codes. Aftercare codes are not to be used for the late effects of trauma but for conditions such as long-term use of anticoagulants, ostomy status, or the presence of a pacemaker. These codes are important in the patient's problem list in the medical record and on the claim form to report to the payer historical and current conditions of the patient.

Don't neglect Z codes—they provide important information on both the problem list and the claim form.


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