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Assigning Pleural Effusion

Published on 

Wednesday, May 11, 2022

 | Coding 


In I-10-CM, under J91 there is an Excludes2 instruction that excludes pleural effusion in heart failure (I50.-). Should pleural effusion also be coded any time a patient has congestive heart failure (CHF)?


No. As coders, we still need to follow all instructions/directions as we have previously been taught. Even though the Excludes2 instruction allows you to code pleural effusion with CHF, it doesn’t mean that it is always appropriate.

Pleural effusion occurs when fluid abnormally accumulates within the pleural spaces and is associated with pulmonary diseases and certain cardiac conditions, but it can also involve other organs.

In ICD-9, pleural effusion with CHF wasn’t to be coded unless it required therapeutic treatment or additional diagnostic studies, etc., e.g., (thoracentesis or decubitus X-ray). The same holds true in ICD-10. If the pleural effusion just shows up on an X-ray, is minimal, and only the CHF is treated, then it is not appropriate to code it; however, if a thoracentesis or additional diagnostic testing/evaluation is performed, then a code for (J91.8) (Pleural effusion in other conditions classified elsewhere) should be assigned in addition to the CHF. Pleural effusion, not elsewhere classified, (NEC) (J90) would not be appropriate in this case since the pleural effusion is associated with CHF.

Pleural effusion in conditions classified elsewhere (J91.x) should also be assigned if the patient has a malignant pleural effusion, filariasis, or influenza.

Pleural effusions that are chronic, have a known underlying cause, and cause no symptoms, are usually not treated with a thoracentesis and/or pleural fluid analysis as it is often not necessary.

Usually, documentation indicates when pleural effusion is related to a patient’s condition. If you can’t determine the cause, query the attending physician for the etiology of the pleural effusion to obtain a more accurate diagnosis code. Pleural effusion, NEC (J90) should seldom be used.


  • Coding Clinic, Second Quarter 2015: Page 15
  • Coding Clinic, Third Quarter 1991 Page: 19 to 20
  • AHA Coding Handbook
  • Merck Manual
Article Author: Susie James, RHIT, CCS
Susie James, RHIT, CCS, is the Manager of Inpatient Coding Services at MMP, Inc. Susie has worked in the coding field for over 30 years and has worked as a coder, coding supervisor, and corporate coding manager for a large multi-facility system in Birmingham. She also worked for Alabama Quality Assurance Foundation (AQAF) as a coding reviewer/auditor before joining the team at Medical Management Plus, Inc. Susie has previously served as the President of the Alabama Association of Health Information Management (AAHIM) on the Board of Directors and currently serves as the Education/Coding Roundtable Chair. She is also a member of the American Health Information Management Association (AHIMA) and has previously served as the Co-chair for AHIMA's Leadership Team. She also served as a facilitator at AHIMA's 85th National Convention in Atlanta Georgia.

This material was compiled to share information.  MMP, Inc. is not offering legal advice. Every reasonable effort has been taken to ensure the information is accurate and useful.