Help ICD Make People Count
Brush up on anatomy and pathophysiology (A&P) to code ICD-10 effectively.
When you hear the term International Classification of Diseases (ICD), what comes to mind? Do you view ICD as a method of communicating a patient’s diagnosis to an insurance carrier to receive payment; or do you like to think of ICD-9-CM codes as magical number combinations that unlock national and local coverage determinations and medical necessity edits? Perhaps you’re consumed with the thought of transitioning from ICD-9 to ICD-10, and wondering why something that has been working for so many years has to change. Some of you may be asking, “What’s the big deal about ICD?”
An internationally endorsed classification facilitates storage, retrieval, analysis, and interpretation of data. Standardized classification permits data comparison within populations over time and between populations at the same point in time. It also allows for nationally consistent data. In short, ICD is a big deal because it makes people count.
WHO Saw the Need for a Diagnosis Classification System
To understand the full impact of ICD, you must first understand the history of the World Health Organization (WHO).
WHO is one of the original agencies of the United Nations. Its objective “is the attainment by all people of the highest possible level of health.”
According to WHO, “To make people count, we first need to be able to count people.” That is what WHO did when it published ICD; it created a medical classification system that allows for counting, tracking and research of diseases, injuries, symptoms, reasons for encounters, factors influencing health status, and external causes of disease and death, such as accidents.
ICD information is used to:
- Study diseases
- Develop preventive measures
- Manage health care allocation of resources
- Measure outcomes
- Monitor and research diseases
Understanding A&P Is Critical
Consider the following examples of how A&P knowledge is necessary in making people count:
Myocardial infarction (MI) or acute myocardial infarction (AMI) is an interruption of blood supply to a part of the heart that causes heart cells to die. It is commonly due to occlusion of a coronary artery following the rupture of a vulnerable atherosclerotic plaque, which is an unstable collection of lipids and white blood cells (especially macrophages) in the wall of an artery. The resulting ischemia and oxygen shortage, if left untreated, can cause damage or death of myocardium.
The ICD-10-CM code range for MI is I21.01–I22.9. To code MI in ICD-10-CM, the following is necessary:
- Heart wall involved
- Initial or subsequent
- ST elevation myocardial infarction (STEMI) or non-ST elevation myocardial infarction (NSTEMI)
Transmural is associated with atherosclerosis involving a major coronary artery. It can be subclassified into anterior, posterior, or inferior. Transmural infarcts extend through the whole thickness of the heart muscle and are usually a result of complete occlusion of the area’s blood supply.
Subendocardial involves a small area in the subendocardial wall of the left ventricle, ventricular septum, or papillary muscles. Subendocardial infarcts are thought to be a result of locally decreased blood supply, possibly from a narrowing of the coronary arteries. The subendocardial area is farthest from the heart’s blood supply and is more susceptible to this type of pathology.
Clinically, an MI can be further subclassified into a STEMI versus an NSTEMI based on electrocardiogram (ECG) changes.
The 12-lead ECG is used to classify MI patients into one of three groups:
- Those with ST segment elevation or new bundle branch block
- Those with ST segment depression or T wave inversion (suspicious for ischemia)
- Those with a so-called nondiagnostic or normal ECG (However, a normal ECG does not rule out AMI.)
To assign a code to this example, you need to be knowledgeable in anatomy and have a good understanding of the disease process.
Let’s take a look at another example found in ICD-10-CM:
Chronic obstructive pulmonary disease (COPD) is one of the most common lung diseases, and refers to chronic bronchitis and emphysema paired together as co-existing diseases. You may also hear it referred to as chronic obstructive lung disease (COLD), chronic obstructive airway disease (COAD), chronic airflow limitation (CAL), or chronic obstructive respiratory disease (CORD).
Lung damage and inflammation in the large airways can result in chronic bronchitis. Chronic bronchitis is defined clinically as a cough with sputum production on most days for three months during a year, for two consecutive years. The wet cough is a result of an increased number and size of goblet cells and mucous glands in the lung airways, which causes airway narrowing. Microscopically, there is infiltration of the airway walls with inflammatory cells. This is followed by scarring and remodeling, which thickens the walls and results in airway narrowing.
Lung damage and inflammation of the air sacs, or alveoli, can result in emphysema. Emphysema is an enlargement of the air spaces distal to the terminal bronchioles, with destruction of their walls. The destruction of air space walls reduces the surface area available for the exchange of oxygen and carbon dioxide during breathing. It also reduces the elasticity of the lung itself, which results in a loss of support for the embedded airways of the lung. These airways are more likely to collapse, causing further limitation to airflow.
The ICD-10-CM code range for COPD is J44.0-J44.9. To code COPD in ICD-10-CM, you must be able to answer the following:
- Does acute lower respiratory infection exist?
- Does acute exacerbation exist?
According to ICD-10-CM Official Guidelines for Coding and Reporting, an acute exacerbation is a worsening or a decompensation of a chronic condition. An acute exacerbation is not equivalent to an infection superimposed on a chronic condition; however, an exacerbation may be triggered by an infection. It is important for coders to have a good understanding of what is involved in the COPD disease process to properly assign a code in ICD-10-CM. Having A&P expertise will help.
It is important for coders to have a good understanding of what is involved in the COPD disease process to properly assign a code in ICD-10-CM. Having a strong foundation of A&P will help.
Updating your A&P skills is just one way you can prepare for ICD-10-CM implementation and ensure proper use of the new code set. Your ultimate goal should be to use the code set as it was intended, by assigning codes to the highest level of specificity so meaningful data can be exchanged.
To help you build a strong A&P foundation to accommodate ICD-10’s greater specificity, AAPC is offering “ICD-10 Anatomy and Pathophysiology” training, which covers all body systems in 14 modules. You can select individual modules or take the complete training course. Find out more.
Rhonda Buckholtz, CPC, CPMA, CPC-I, is vice president of ICD-10 training and education at AAPC.
Donna L. Stewart, CPC, CPC-H, CPC-P, CPC-I, is manager of compliance at Children’s Hospital of the King’s Daughters in Norfolk, Va. and is owner and president of Professional Impact, Inc., a Virginia Beach based consulting company. She has nearly 30 years of experience in health care coding, auditing, consulting, compliance, and billing. As PMCC instructor, Stewart provides training for coders, auditors, physicians, and staff members, and conducts classes and seminars in coding, E/M auditing, reimbursement, compliance, and documentation. She is very active with AAPC nationally and through her local chapter. Stewart was recognized as the AAPC Networker of the Year for 2004.