R18

Non-billable

Ascites

Ascites

This is a header/category code. For billing purposes, use a more specific child code from the list below.

Status

Non-billable / Header

Block

R10-R19

Child Codes

2

Coding Notes

Includes

Conditions included under this code

  • fluid in peritoneal cavity

Excludes 1

Codes that cannot be used together with this code (mutual exclusion)

  • ascites in alcoholic cirrhosis (K70.31)
  • ascites in alcoholic hepatitis (K70.11)
  • ascites in toxic liver disease with chronic active hepatitis (K71.51)

Excludes 2

Conditions not included here, but the patient may have both

  • abnormal findings on antenatal screening of mother (O28.-)
  • certain conditions originating in the perinatal period (P04-P96)
  • signs and symptoms classified in the body system chapters
  • signs and symptoms of breast (N63, N64.5)
  • congenital or infantile pylorospasm (Q40.0)
  • gastrointestinal hemorrhage (K92.0-K92.2)
  • intestinal obstruction (K56.-)
  • newborn gastrointestinal hemorrhage (P54.0-P54.3)
  • newborn intestinal obstruction (P76.-)
  • pylorospasm (K31.3)
  • signs and symptoms involving the urinary system (R30-R39)
  • symptoms referable to female genital organs (N94.-)
  • symptoms referable to male genital organs (N48-N50)

Child Codes (2)

Also Known As / Clinical Terms

Frequently Asked Questions

What is ICD-10 code R18?

ICD-10-CM code R18 represents "Ascites". It is a non-billable header code — use a more specific child code for billing purposes.

Is R18 a billable code?

No, R18 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 2 child codes under R18.

What chapter is R18 in?

R18 is in Chapter 18: Symptoms, Signs and Abnormal Clinical and Laboratory Findings (codes R00-R99).

What codes cannot be used with R18?

R18 has Excludes1 notes indicating codes that cannot be used together with it, including: ascites in alcoholic cirrhosis (K70.31); ascites in alcoholic hepatitis (K70.11); ascites in toxic liver disease with chronic active hepatitis (K71.51).

What are the subcategories under R18?

R18 has 2 child codes, including: R18.0 (Malignant ascites), R18.8 (Other ascites).

What are the UMLS CUIs for R18?

R18 is linked to 2 UMLS Concept Unique Identifiers: C0003962, C3665480. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.