Coding in surgery: impact of a specialized coding proforma in hepato-pancreato-biliary surgery

Coding inaccuracies in surgery misrepresent the productivity of hospitals and outcome data of surgeons. The aim of this study was to audit the extent of coding inaccuracies in hepato-pancreato-biliary (HPB) surgery and assess the financial impact of introducing a coding proforma.

Coding of patients who underwent elective HPB surgery over a 3-month period was audited. Codes were based on International Classification of Diseases 10 and Office of Population and Census Surveys-4 codes. A coding proforma was introduced and assessed. New human resource group codes were re-assigned and new tariffs calculated. A cost analysis was also performed.

Prior to the introduction of the coding proforma, 42.0% of patients had the incorrect diagnosis and 48.5% had missing co-morbidities. In addition, 14.5% of primary procedures were incorrect and 37.6% had additional procedures that were not coded for at all. Following the introduction of the coding proforma, there was a 27.5% improvement in the accuracy of primary diagnosis (P < 0.001) and 21% improvement in co-morbidities (P = 0.002). There was a 7.2% improvement in the accuracy of coding primary procedures (P = not significant) and a 21% improvement in the accuracy of coding of additional procedures (P < 0.001). Financial loss as a result of coding inaccuracy over our 3-month study period was £56 073 with an estimated annual loss of £228 292.

Coding in HPB surgery is prone to coding inaccuracies due to the complex nature of HPB surgery and the patient case-mix. A specialized coding proforma completed 'in theatre' significantly improves the accuracy of coding and prevents loss of income.