The coding and sequencing of respiratory failure continues to present a challenge to the coding community. The First Quarter 2005 issue of Coding Clinic establishes some new guidelines for HIM coders to follow. Before applicants take the upcoming coding certification exams, they should ensure that they clearly understand the new guidelines and know what to look for in the medical record documentation. Although respiratory failure is not an uncommon diagnosis in the acute care setting, the underlying causes of it and the level of accurate documentation of it vary widely. This article will explore the new instructions.
The definition of acute respiratory failure is severe respiratory dysfunction resulting in abnormalities of oxygenation or CO2 elimination and impairing or threatening the function of vital organs. Respiratory failure can be a failure of oxygenation (the tissues of the lung are not functioning properly), a failure of ventilation (an impairment of airflow in and out of the lungs) or both. An example of a failure of oxygenation would be an acute exacerbation of bronchial asthma in a patient with lung tissue damage due to emphysema. An example of a failure of ventilation would be compression of the trachea blocking the airflow, caused by metastatic carcinoma of the thoracic lymph nodes. A patient with acute respiratory failure usually presents with increased work of breathing as typified by rapid respiratory rate, use of accessory muscles of respiration (such as intercostal muscle retraction) and possibly paradoxical breathing and/or cyanosis.
Respiratory failure is a life-threatening disorder that requires close patient monitoring and evaluation, with aggressive management usually requiring placement of the patient in a monitored bed, aggressive respiratory therapy and/or mechanical ventilation. However, the absence of mechanical ventilation does not preclude the diagnosis of respiratory failure. In many cases, respiratory failure is the final pathway of a disease process, or a combination of different processes, and can be a result of an abnormality in any of the components of the respiratory system, peripheral nervous system, central nervous system, respiratory muscles and chest wall muscles. In most cases the treatment is directed toward correction of the hypoxemia and stabilization of the ventilatory and hemodynamic status.
Respiratory failure, code 518.81, may be assigned as a principal diagnosis when it is the condition established after study to be chiefly responsible for occasioning admission to the hospital, and the selection is supported by the Alphabetic Index and Tabular List. However, chapter-specific coding guidelines (obstetrics, poisoning, HIV, sepsis, newborn) that provide sequencing direction take precedence. Res-piratory failure may be listed as a secondary diagnosis if it occurs after admission. Again, the fact that the respiratory failure was managed without intubation and mechanical ventilation does not preclude the use of 518.81. If the diagnosis is otherwise supported by the contents of the medical record, then respiratory failure should be assigned as the principal diagnosis.
When a patient is admitted with respiratory failure and another acute condition (e.g., myocardial infarction, cerebrovascular accident), the principal diagnosis will not necessarily be the same for every admission. Selection of the principal diagnosis will be dependent on the circumstances of admission. If both the respiratory failure and the other acute condition are responsible for occasioning the admission to the hospital, the guideline regarding two or more diagnoses that equally meet the definition for principal diagnosis (Section II, C) may be applied in these situations.
This new advice is very important to understand as it is different than that previously stated in guideline #1 and guideline #2, previously published in Coding Clinic, Second Quarter 1991, p. 3. It is, however, consistent with advice previously published in Coding Clinic, November-December 1987; Second Quarter 1990, pp. 11-12; Third Quarter 1991, p. 14; First Quarter 1993, p. 25; Second Quarter 2000, p. 21; and First Quarter 2003, p. 15.
To summarize the revised instructions, if acute respiratory failure and another acute condition both equally meet the definition of principal diagnosis, that is, both are responsible for occasioning the admission to the hospital, the instruction under Section II, C of the Coding Clinic Official Coding Guidelines may be followed:
"C. Two or more diagnoses that equally meet the definition for principal diagnosis
In the unusual instance when two or more diagnoses equally meet the criteria for principal diagnosis as determined by the circumstances of admission, diagnostic workup and/or therapy provided, and the Alphabetic Index, Tabular List or another coding guideline does not provide sequencing direction, any one of the diagnoses may be sequenced first."
But before automatically sequencing respiratory failure as principal diagnosis on all cases in which it's present on admission, keep in mind that there are chapter-specific guidelines specifying that some codes have sequencing priority over codes from other chapters. For example:
HIV/AIDS: For a patient with HIV or AIDS and respiratory failure, the HIV code is sequenced first because there is a chapter-specific guideline (Section I, C, 1, a, 2, a) that provides sequencing directions specifying that if a patient is admitted for an HIV-related condition, the principal diagnosis should be 042, followed by additional diagnosis codes for all reported HIV-related conditions.
Poisoning (Chapter 17): The poisoning codes are sequenced first because there is a specific guideline (Section I, C, 17, e, 2, d) specifying that the poisoning code is sequenced first, followed by a code for the manifestation.