Close Server: KOPWWW05 | Not logged in

CCS Prep

Understanding the Outpatient ICD-9-CM Guidelines

April 7, 2008

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 all outpatient care settings, including physician offices and clinics. Note: this particular article will focus on ICD-9-CM coding issues only, as found in the American Hospital Association (AHA)'s Coding Clinic: ICD-9-CM Official Guidelines for Coding and Reporting. The most recent version released was effective Oct. 1, 2007.

Consistent with the inpatient guidelines, the outpatient guidelines are developed and approved by the four cooperating parties for ICD-9-CM, which include the AHA, American Health Information Management Association (AHIMA), Centers for Medicare and Medicaid Services (CMS) and National Center for Health Statistics (NCHS). The guidelines are updated on a regular basis and coding professionals must review all portions of the guidelines to ensure appropriate coding of all disease processes and also ICD-9-CM procedures, if applicable.

One of the most important aspects of understanding outpatient coding guidelines is an awareness of 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. In many outpatient cases, the diagnosis code for a presenting sign or symptom must be assigned because a definitive diagnosis has not yet been determined.

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.

Many outpatient visits involve diagnostic tests and studies and there are several outpatient coding guidelines to direct the coder in these instances:

 For encounters for routine laboratory/radiology testing in the absence of any signs, symptoms, or associated diagnosis, assign V72.5 (Radiological examination, NEC) and/or V72.6 (Laboratory examination). If routine testing is performed during the same encounter as a test to evaluate a sign, symptom or diagnosis, it is appropriate to assign both the V code and the code describing the reason for the non-routine test.

 For patients receiving preoperative evaluations only, sequence first a code from category V72.8, Other specified examinations, to describe the pre-op consultations. Assign a code for the condition to describe the reason for the surgery as an additional diagnosis. Code also any findings related to the pre-op evaluation.

 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.

The last guideline above is meant to resolve 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 and separately documented by a physician.

Patients may receive therapeutic treatment in the outpatient setting, and the first-listed code should represent the diagnosis, condition, problem or other reason for the encounter/visit that is chiefly responsible for the outpatient services provided. The only exception to this rule is that when the primary reason for the encounter is chemotherapy, radiation therapy or rehabilitation, the appropriate V code for the service should be sequenced as the first-listed code and the diagnosis or problem for which the service is provided is coded in subsequent positions.

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.

Patients receiving routine prenatal visit services with no documented complications should have code V22.0 (Supervision of normal first pregnancy), or V22.1 (Supervision of other normal pregnancy) sequenced as the first-listed diagnosis. No other codes from Chapter 11 (Complications of Pregnancy, Childbirth, and the Puerperium) should be assigned, indicating that a complication exists.

A common question that arises in the outpatient arena involves the assignment of codes for secondary conditions. Although outpatient care is typically related to the assessment and/or treatment of the primary condition for which the paient 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 conditions 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. History codes (V10 - V19) may be assigned as secondary conditions if the historical condition or family history has an impact on current care or it influences treatment.

Although the External Cause of Injury (E codes) are not required by regulation in many states, 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 and they represent "complete" coding. In addition, Medicare and other government payers require the assignment of E codes for poisoning and adverse effects of drugs, medicinal or biological substances. 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.

Coding professionals who assign E codes must review the specific related coding guidelines, beginning on page 78. Important guidelines include the following:

 Assign an appropriate E code for the initial encounter of an injury, poisoning or adverse effect of drugs, NOT for subsequent treatment. External cause of injury (E codes) may be assigned while the acute fracture codes are still applicable.

 Multiple E codes may be necessary to fully explain the cause of injury, poisoning or adverse effect. If two or more drugs, medicinal or biological substances are reported, code each individually unless the combination code is listed in the Table of Drugs and Chemicals. In that case, assign the E code for the combination.

 There is an E code hierarchy that dictates which E codes take priority over other E codes. In general, the hierarchy is as follows:

 Child and adult abuse


 Cataclysmic events

 Transport accidents

Many of the guidelines related to the use of the ICD-9-CM coding system for disease processes 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 V86.1 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 - V86.1) 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.

In addition, there are other chapter specific coding guidelines throughout the official guidelines for which each coder assigning outpatient codes should adhere. For example, outpatient coders should be familiar with the guidelines related to injuries, traumatic fractures, burns, and adverse effects, poisoning and toxic effects.

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:

The guidelines are published in the Fourth Quarter 2007 Coding Clinic for ICD-9-CM (Volume 24, Number 4) 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. When you are ready, take the following quiz to test your knowledge. Assign E codes for cause of injury, if applicable.

1. A pregnant patient at 26-weeks gestation had a 1-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 3-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. 790.29, 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 ventricular shunt previously placed for spina bifida related hydrocephalus, 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: distal radial/ulnar 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 skin lesion removed returns for a wide excision of a malignant melanoma on the left calf. Thearea 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 uncontrolled diabetes. 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 hepatomegaly 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, 789.1

b. V58.11, 250.62, 250.42, 789.1

c. V58.11, 162.9, 250.62, 357.2, 250.42, 583.81, 789.1

d. 162.9, 250.02, 789.1

This month's column has been prepared by Cheryl D'Amato, RHIT, CCS, director of HIM, facility solutions, and Melinda Stegman, MBA, CCS, clinical technical editor, Ingenix (, 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 AHA.
CPT is a registered trademark of the AMA.


1. b: Incorrect answers include code 790.29, which excludes that complicating pregnancy and refers the coder to subcategory 648.8. V22.2 is not appropriate for this visit because the pregnancy is not incidental, and V22.0 implies a normal pregnancy follow-up visit, not applicable for this encounter. The correct code is 648.83; 648.80 has a fifth digit of 0, which is unspecified, and this is an antepartum condition.

2. d: Incorrect answers include 996.2; according to Coding Clinic (4th Qtr 1997), because there is no actual complaint or problem with the shunt, the malfunction code is not applicable. Code 783.40 (Lack of normal physiological development) is also not applicable to this case. The patient's development has been described as normal; the catheter is just no longer large enough for him. Only codes V53.01 (Fitting and adjustment of cerebral ventricular [communicating] shunt) and 741.00 (Spina bifida with hydrocephalus, no region specified) should be assigned.

3. b: Incorrect answers include 813.41, which is non-specific and the documentation indicated that the fracture involved both the distal radius and ulna. Also, the symptom code 729.5 (pain in limb) should not be assigned when the definitive condition (the fracture) is documented. The correct codes are 813.44 (Fracture of radius with ulna, lower end) and E917.5 (Striking against or struck by object in sports with subsequent fall).

4. c: Incorrect answers include 709.9 (Unspecified disorder of skin and subcutaneous tissue), 238.2 (Neoplasm of uncertain behavior of skin) and V76.43 (Special screening for malignant neoplasm; skin). When a malignant lesion has been excised and the patient presents for wide excision, the malignant lesion is coded for the subsequent encounter because it is still being addressed in this initial phase of treatment. The correct code is 172.7 (Malignant melanoma of skin; lower limb, including hip).

5. c: Because the patient was seen on this encounter for chemotherapy, the first-listed diagnosis code should be V58.11 (Encounter for antineoplastic chemotherapy), and the lung cancer (162.9) should be coded as well. Diabetic neuropathy and nephropathy are documented and should be coded as 250.62, 357.2, 250.42, 583.81, with the 5th digit of "2," on the diabetes codes, indicating uncontrolled type II/unspecified type diabetic. Code 789.1 (Hepatomegaly) should also be assigned as a secondary condition.

CCS Prep Archives

View New Jobs, Events and More


Back to Top

© 2017 ADVANCE Healthcare, an Elite CE company