How do you describe an operation?

What a patient thinks of as 'an operation' can actually be made up of a number of separate procedures and interventions. Operations can be relatively simple, for example removal of a skin lesion, or they can be complex, such as when a patient has suffered a serious road traffic accident and has multiple injuries that need to be treated. Similarly, there are different ways in which a given operation can be performed, such as using 'key hole' surgery. These different aspects of each operation are currently recorded separately in HES using the OPCS-4.4 classification of interventions and procedures, fourth revision.

In certain very complex cases, it is possible that there were actually a considerable number of individual procedures and interventions; HES records store up to the first twelve (four prior to 2002-03) OPCS-4 codes recorded for each episode. The 'main procedure/intervention' need not be the first, eg where major surgery is preceded by a biopsy, although it should be the one that is the most resource intensive. Any additional OPCS-4 codes (where they occur) are known as 'secondary procedures/interventions'.

When looking at HES data, you may want to look for a combination of OPCS-4 codes within a record and not just the main procedure/intervention.

What are OPCS-4 codes?

OPCS-4 codes consist of a letter followed by three figures. The letters denote the 24 chapters of the classification - each chapter dealing with a different part, or 'system' of the body. There are more than 6,000 codes altogether, but for many purposes it is acceptable to group codes at the 3-character level. For example, all codes beginning J04 are for "repair of liver".

However, where more precision is required you will need to use the sub-division indicated by the final character. In the case of JO4, the code for "repair of laceration of liver" is J04.2 (note the use of the point separating the 3-character 'group' code from the final number).

There are tables available from HESonline containing data relating to OPCS-4 codes at the 3-character level and 4-character level. As well as a table that provides an aggregate summary of all the procedure codes recorded at the 3-character level, including main (first recorded) procedure/intervention.

The procedures and interventions in the tables are presented in code order, rather than by name.

Using OPCS-4 to classify operations

The list of OPCS-4 chapters below should help you locate the particular procedure or intervention you need:

• A - Nervous System
• B - Endocrine System and Breast
• C - Eye
• D - Ear
• E - Respiratory Tract
• F - Mouth
• G - Upper Digestive Tract
• H - Lower Digestive Tract
• J - Other Abdominal Organs - principally digestive
• K - Heart
• L - Arteries and Veins
• M - Urinary
• N - Male Genital Organs
• P - Lower Female Genital Tract
• Q - Upper Female Genital Tract
• R - Female Genital Tract associated with pregnancy and childbirth and Puerperium
• S - Skin
• T - Soft Tissue
• U - Diagnostic Imaging, Testing and Rehabilitation
• V - Bones and Joints of Skull and Spine
• W - Other Bones and Joints
• X - Miscellaneous Operations
• Y - Subsidiary Classification of Methods of Operation
• Z - Subsidiary Classification of Sites of Operation