Understanding the Official Outpatient ICD-9-CM Coding and Reporting Guidelines

Vol. 13 •Issue 5 • Page 6
CCS Prep!

Understanding the Official Outpatient ICD-9-CM Coding and Reporting Guidelines

This month’s CCS Prep! column will review components of the ICD-9-CM Official Guidelines for Coding and Reporting, specifically addressing outpatient reporting. With the proliferation of outpatient service areas throughout the country and the advent of Medicare’s outpatient prospective payment system (OPPS), scrutiny on outpatient coding has never been higher. It is crucial that the coder thoroughly understand the differences between inpatient and outpatient coding guidelines and the appropriate use of outpatient guidelines for outpatient care settings. Note: this particular article will focus on ICD-9-CM coding issues only; CPT/HCPCS issues will be covered in a later article.

Consistent with the inpatient guidelines, the outpatient guidelines are developed and approved by the four cooperating parties for ICD-9-CM, which include the American Hospital Association (AHA), American Health Information Management Association (AHIMA), Centers for Medicare and Medicaid Services (CMS) and National Center for Health Statistics (NCHS). The guidelines were updated in October 2002 and include a number of notable revisions.

One of the most important aspects of understanding outpatient coding guidelines is understanding how they differ from inpatient guidelines. The most important difference is that the Uniform Hospital Discharge Data Set (UHDDS) definition of principal diagnosis applies only to inpatients in acute, short-term, general hospitals. This means that the coding guidelines for inconclusive diagnoses (those with terminology indicating “probable,” “suspected,” “rule-out,” etc.) were developed for inpatient reporting and do not apply to outpatients. Because diagnoses are often not established at the time of the initial outpatient encounter or visit, this is an extremely important guideline.

The terms encounter and visit are often used interchangeably in describing outpatient service contacts and therefore, are also used interchangeably in the guidelines, without distinguishing one from the other. Another aspect of terminology involves the use of the term first-listed for outpatient visits in lieu of principal diagnosis. List first the ICD-9-CM code for the diagnosis, condition, problem or other reason for the encounter/visit shown in the medical record to be chiefly responsible for the services provided. But as mentioned above, do not code diagnoses documented as “probable,” “suspected,” “questionable,” “rule-out” or “working diagnosis.” Rather, code the condition(s) to the highest degree of certainty for that encounter/visit, such as symptoms, signs or abnormal test results or other reason for the visit.

An important revision in the October 2002 guidelines includes the following:

“For outpatient encounters for diagnostic tests that have been interpreted by a physician, and the final report is available at the time of coding, code any confirmed or definitive diagnosis(es) documented in the interpretation. Do not code related signs and symptoms as additional diagnoses.” (p. 51)

The above guideline is meant to clear up confusion concerning assigning diagnosis codes at the point of patient registration. The guideline indicates that if the final report is available at the time of coding, that the physician-confirmed diagnosis or diagnoses should be coded. Note that if the definitive diagnosis is coded, its inherent signs and symptoms should NOT be coded additionally. In some facilities, it has been common practice for coding or billing staff to add signs and symptoms diagnosis codes in addition to definitive codes for medical necessity reasons. This practice is inappropriate, and all coding guidelines should be followed. Also note that the guideline clearly designates the confirmed or definitive diagnosis(es) as those that a physician has interpreted, so conditions based upon abnormal test values alone (such as lab tests) should not be coded unless substantiated by a physician.

For ambulatory surgery outpatient coding, code the diagnosis for which the surgery was performed. If the postoperative diagnosis is known to be different from the preoperative diagnosis at the time the diagnosis is confirmed, select the postoperative diagnosis for coding because it is the most definitive.

Another important outpatient coding guideline concerns patients receiving diagnostic services only during an encounter/visit. Sequence first the diagnosis, problem or other reason for the encounter/visit shown in the medical record to be chiefly responsible for the outpatient services provided during the encounter/visit.

A common question that arises in the outpatient arena involves the assignment of codes for secondary conditions. Although outpatient care is typically concerned with the assessment and/or treatment of the primary condition for which the patient is seen, chronic conditions treated on an ongoing basis may be coded and reported as many times as the patient receives treatment and care for the condition(s). Also, code all documented conditions that coexist at the time of the encounter/visit and require or affect patient care treatment or management. A common example is an ambulatory surgery patient with a long-term history of severe chronic obstructive pulmonary disease (COPD) and congestive heart failure (CHF). Although not the condition for which the surgery was performed, both the attending physician and the anesthesiologist would be concerned with this history and would most likely monitor and/or treat the operative and postoperative phases of the visit differently than they would a patient with no such history.

Although the External Cause of Injury (E-codes) are not required by regulation, the vast majority of coding professionals assign them because they are used by many governmental agencies in the assessment and development of injury prevention strategies. E-codes should never be assigned as a first-listed diagnosis, and should capture how the injury or poisoning happened (cause), the intent (unintentional or accidental; or intentional, such as suicide or assault), and the place where the event occurred. These codes are assigned most frequently in the emergency department setting.

Many of the guidelines related to the use of the ICD-9-CM coding system are the same as those for inpatient visits, so the outpatient coder must also review the general guidelines that apply to all settings. The most critical rule involves beginning the search for the correct code assignment through the Alphabetic Index. Never begin searching initially in the Tabular List, as this will lead to coding errors. Codes from the 001.0 through V83.89 range should be selected to identify diagnoses, symptoms, conditions, problems complaints or other reason(s) for the encounter/visit.

ICD-9-CM provides codes to deal with encounters for circumstances other than a disease or injury. The Supplementary Classification of Factors Influencing Health Status and Contact with Health Services (V01.0 – V83.89) is provided to deal with occasions when circumstances other than a disease or injury are recorded as a diagnosis or problem. This situation is much more common in the outpatient setting than in the inpatient arena, so coders must make themselves very familiar with the V-code section of ICD-9-CM.

The official guidelines should be the principal basis on which all coding and sequencing decisions are made, but only when the ICD-9-CM codebook does not provide specific direction. A copy of the ICD-9-CM Official Guidelines for Coding and Reporting can be downloaded from the NCHS Web site at www.cdc.gov/nchs/data/icdguide.pdf. The guidelines may also be downloaded from the AHIMA Coding Communities of Prac-tice Coding Web site at http://www.cop.ahima.org/COP and are published in Fourth Quarter 2002 Coding Clinic and can be found on the CD-ROM that includes the official versions of ICD-9-CM.

Take some time now and review the Diagnostic Coding and Reporting Guidelines for Outpatient Services. We will discuss other sections in upcoming issues of CCS Prep! When you are ready, take the following quiz to test your knowledge. Assign E-codes for cause of injury, if applicable.

1. A patient at 26-weeks gestation had a one-hour glucose screening test. Results of this test showed a blood sugar level of 160 mg/dl. Subsequently, the patient presents to the outpatient laboratory department with a physician order for a three-hour glucose tolerance test. The reason for the test as documented on the order is: abnormal glucose on screening, rule out gestational diabetes. What is the correct diagnosis code set for this outpatient ancillary services encounter?

a. 790.2, V22.2

b. 648.83

c. V22.0, 648.83

d. 648.80

2. The patient is a 9-year-old male who had a shunt placed, and the child has outgrown the length of the peritoneal catheter. He is neurologically normal and otherwise having no problems at all. It was recommended he undergo elective lengthening of the distal catheter. What is the correct diagnosis code set for this outpatient ambulatory surgery services encounter?

a. 996.2, V53.01, 741.00

b. 996.2, 741.00

c. 996.2, 741.00, 783.40

d. V53.01, 741.00

3. The patient was playing basketball today, collided with another player, fell and hurt his left wrist. He is right-hand dominant. Examination revealed tenderness and swelling of the wrist, especially the volar aspect. X-ray shows a fracture of the ulnar styloid and distal radial epiphyseal plate fracture with slight posterior displacement of the distal fragment of about 4 mm. Diagnosis: Colles’ fracture. What is the correct diagnosis code set for this outpatient emergency department services encounter?

a. 813.41, E917.5

b. 813.44, E917.5

c. 813.41, 729.5, E917.5

d. 813.44, 729.5, E917.5

4. A patient who has had a lesion removed returns for a wide excision of a malignant melanoma on the left calf. The area excised consists of a 3-cm diameter area. A layer closure is required to close the defect. The pathology report shows clear margins. What is the correct diagnosis code set for this outpatient ambulatory surgery services encounter?

a. 172.7, 238.2

b. 709.9

c. 172.7

d. V76.43

5. This patient is a 57-year-old male who presents to the outpatient department for chemotherapy for his lung cancer, which has been complicated by his diabetes as it has been uncontrolled. He had surgery for the lung cancer in September and has now undergone chemotherapy with Taxol and Carboplatin. His diabetes is complicated by neuropathy and nephropathy. His hepato-megaly has enlarged from the last time that I saw him. Question whether this is fatty infiltration due to poor diabetes control, or whether there is now some involvement with metastatic carcinoma. Taxol and Carboplatin were infused today; see infusion sheet. One difficulty here is the cyclic nature of his treatment regimen, likely to produce major shifts in his glucose, which is already difficult to control. The patient will need to monitor his glucose levels closely and follow up with Dr. Johnson. Which of the following is the correct ICD-9-CM code set for this outpatient visit?

a. 162.9, 250.62, 357.2, 250.42, 583.81, 272.4, 789.1

b. V58.1, 250.62, 250.42, 272.4, 789.1

c. V58.1, 162.9, 250.62, 357.2, 250.42, 583.81, 272.4, 789.1

d. 162.9, 250.02, 272.4, 789.1

This month’s column has been prepared by Cheryl D’Amato, RHIT, CCS, director of HIM, and Melinda Stegman, MBA, CCS, manager of clinical HIM services, HSS Inc. (www.hssweb.com), which specializes in the development and use of software and e-commerce solutions for managing coding, reimbursement, compliance and denial management in the health care marketplace.

Coding Clinic is published quarterly by the American Hospital Association.

CPT is a registered trademark of the American Medical Association.

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