Chronic Obstructive Pulmonary Disease


MS-DRG	CMS DRG (Prior to 10/1/2007)
190	Chronic obstructive pulmonary disease with MCC	088	Chronic obstructive pulmonary disease
191	Chronic obstructive pulmonary disease with CC
192	Chronic obstructive pulmonary disease w/o CC/MCC

Chronic Obstructive Pulmonary Disease

Obstructive lung disease is a chronic or recurrent reduction in expiratory airflow within the lung. It is characterized by decreased airflow rates during expiration, often accompanied by retained residual capacity due to trapped gas. The most common etiology is cigarette smoking or other respiratory irritants. Patients with severe case of COPD may develop secondary pulmonary hypertension. Acute respiratory infections and/or other environmental factors may trigger exacerbation of COPD. Its major obstructive disorders are:

Asthma is a pulmonary disease characterized by airway inflammation, reversible airway obstruction manifested by airway hyper-responsiveness to a variety of stimuli

Bronchiectasis is a chronic dilation of bronchi or bronchioles as a sequel of inflammatory disease or obstruction.

Emphysema is characterized by abnormal permanent enlargement of the airspaces distal to the terminal bronchiole (those parts containing alveoli) with destruction in their walls and reduction in their numbers.

Bronchitis is an inflammation of the mucous membrane of the bronchial tubes.

Chronic bronchitis is a condition of bronchial tree characterized by cough, hypersecretion of mucus, and expectoration of sputum over a long period of time.

Acute bronchitis is an acute inflammation of the bronchus, generally self-limited and with complete healing and return of function

Signs/Symptoms/Conditions

Bronchospasms
Chronic productive cough
Clubbing of nails
Hypoxemia
Increased dyspnea, tachypnea
Orthopnea
Persistent /diffuse wheezing, diminished breath sounds, prolonged expiration
Shortness of breath
Speech difficulty
Sputum production (note sputum color, amount and characteristic)
Tachycardia
Use of accessory respiratory muscles

Tests

Arterial blood gases (indicating respiratory failure) show decreased pO2 or increased pCO2
Chest x-rays may indicate hyperinflation or emphysematous
Pulmonary function test revealing obstructive ventilatory impairment or increased residual volume

Documenting Obstructive Lung Disease

In assigning a diagnosis of chronic obstructive pulmonary disease, review the medical record and carefully look for physician documentation indicating the patient has COPD.
Identify documentation of signs, symptoms, and conditions, therapeutic drug treatment in medical record substantiating the diagnosis of COPD.
Documentation must always be clear and concise when identifying asthma with other conditions. Physicians must identify the presence of "status asthmaticus".

Principal Diagnosis Codes that Commonly Group to DRG 190

491.1: Bronchitis, chronic, mucopurulent
*491.2x: Bronchitis, chronic, obstructive
491.8: Bronchitis, chronic, other
491.9: Bronchitis, chronic, unspecified
492.0: Bleb, emphysematous
492.8: Emphysema, other
493.20: Asthma, chronic obstructive, without mention of status asthmaticus
493.21: Asthma, chronic obstructive, with status asthmaticus
493.22: Asthma, chronic obstructive, with acute exacerbation
*494.x: Bronchiectasis
496: Obstruction, airway, chronic, other
506.4: Condition, respiratory, chronic, due to fumes and vapors
506.9: Condition, respiratory, unspecified, due to fumes and vapors
748.61: Bonchiectasis, congenital

* Code Range

Coding Guidelines

Acute bronchitis and COPD

Assign code 491.21, Obstructive chronic bronchitis, with (acute) exacerbation, use additional code 466.0, to indicate acute bronchitis
Acute exacerbation of chronic obstructive bronchitis is not he same as acute bronchitis

Acute and Chronic Obstructive Bronchitis

Assign code 491.22, obstructive chronic bronchitis with acute bronchitis

Chronic Obstructive Pulmonary Disease

Do not assign code 496 with any code from categories 491 - 493

COPD with acute exacerbation

When the cause of acute exacerbation of COPD is not clearly identified, code 491.21 should be assigned.
Coder must not attempt a more specific identification of "acute exacerbation" when there is no physician documentation of the exact nature of the exacerbation. (Coding Clinic, 3rd Quarter, 1988, p 5).

Abnormal Findings

Coder should never use laboratory values or chest radiography results alone to assign a code for chronic pulmonary obstruction.

Respiratory Insufficiency and COPD

Respiratory insufficiency (518.82) is integral to COPD and should not be coded as an additional code with chronic obstructive bronchitis (491.2X), emphysema (492.X), chronic obstructive asthma (493.2X or COPD (496). (Coding Clinic, 2nd Quarter, 1991, p 21).

COPD AS A SECONDARY DIAGNOSIS

COPD as a secondary diagnosis requires documentation in the medical record (history, treatment, anesthesiologist's anesthesia evaluation, etc.) that the patient has COPD.
Any conflicting information should be clarified with the physician. (See Coding Clinic, second quarter 2000, page 15, and Coding Clinic, second quarter 1992, pages 16 and 17.)
If the only mention of COPD is on an x-ray, the diagnosis should be clarified with the physician, because COPD is found on many elderly patients' chest x-rays when other clinical substantiation, treatment or history of COPD is not present. (See Coding Clinic, second quarter 1990, pages 15 and 16)

COPD on anesthesia evaluation

A diagnosis of COPD on an anesthesia evaluation signed by the anesthesiologist can be coded, provided there is no conflicting documentation in the medical record and/or the coder is certain COPD is a valid diagnosis. (See Coding Clinic, second quarter 2000, page 15 and Coding Clinic, second quarter 1992, pages 16 and 17.)

Chronic Obstructive Asthma

Use 5th digit "0" to indicate unspecified, "1" with status asthmaticus and "2" with (acute) exacerbation.
The physician must document the presence of "status asthmaticus" before assigning the 5th digit "1" with codes in category 493, Asthma (Coding Clinic, 1991, 1st Quarter, p13, Coding Clinic 1998, 3rd Quarter p.9 and 10).

Acute bronchitis/Emphysema/Chronic Obstructive Asthma

Acute bronchitis and emphysema are coded 466.0 and 492.8.
Acute bronchitis and chronic obstructive asthma are coded 466.0 and 493.2x. (See Coding Clinic, volume 10, number 5 1993, page 4 this advice was effective 6/11/92, and Coding Clinic, fourth quarter 1993, page 41.)

Asthma/COPD

When diagnoses of asthma and COPD are documented, code 493.2x is used. Codes 493.0x, 493.1x and 493.9x are used to classify asthma in patients without COPD.

A new fifth-digit of "2" indicating acute exacerbation was added to category 493, asthma.

Code 466.0, acute bronchitis no longer excludes acute bronchitis with asthma 493.0-493.9 with fifth-digit of 2, but code 493.2, chronic obstructive bronchitis, excludes acute bronchitis. (See tabular list in ICD-9-CM; Coding Clinic, fourth quarter 2000, page 42; and Coding Clinic, second quarter 1990, page 20.)

Pneumonia/Asthma/COPD

Chronic obstructive bronchitis (491.20) and pneumonia (486) are always coded separately.
Pneumonia is not an acute exacerbation of COPD. (See Coding Clinic, third quarter 1997, and page 9.)
If both asthma and pneumonia are present, each should be coded. (See Coding Clinic, first quarter 1992, page15.)

Asthmatic Bronchitis

Asthmatic bronchitis not specified as chronic is coded 493.90.

Chronic obstructive asthma is coded to 493.2

Acute exacerbation of chronic asthmatic bronchitis requires further specificity to identify the acute attack, such as a superimposed infection (purulent) of the bronchial tree, marked or severe respiratory distress, or respiratory failure. (See ICD-9-CM coding updates for 10/1/02 and Coding Clinic, November-December 1984, page 17.)

Mucopurulent Bronchitis

Chronic or recurrent mucopurulent bronchitis is coded 491.1. (See Coding Clinic, third quarter 1988, and page 12.)
Acute or subacute mucopurulent bronchitis is coded 466.0. (See ICD-9-CM, index to diseases, and Coding Clinic, third quarter 1988, page 12.)