Background: To date we lack official data on tipology of Diagnosis Related Groups (DRGs) and their quality in Italian Respiratory Intermediate Care Units (RICUs).
Aim: The objective of the study was to collect data on the activity of 26 Italian RICUs and to evaluate the quality of the DRGs generated.
Methods: The primary and secondary diseases, the procedures carried out and their coding using the ICD9 system (valid Italy until 2000) were collected from the discharge forms of patients admitted to RICUs. To obtain the DRG, these codes were automatically recoded in the ICD9-CM classification system by Grouper 10. Afterwards, the same diseases and procedures were directly processed by the ICD9-CM classification system. Finally, in order to evaluate the quality of care, the DRGs generated by the ICD9 classification system were compared to DRGs generated by the ICD9-CM classification system.
Results: The average weight of the patients cared for in an Italian RICU was 2.05 using the ICD9 classification system and 2.53 using the ICD9-CM classification system. Some non-complicated DRGs (80-97) or non specific DRGs (101-102) were set to zero; others, like DRG 87 appear due to the ability of the ICD9-CM classification system to recognise and accept the fifth digit of the Respiratory Failure code (518.81). The difference in terms of DRG scores generated by the two codification systems was 360.5 DRG points in favour of ICD9-CM. More than 1 million Euro of reimbursements have been lost, as the average national reimbursement for each DRG score is Euro 2,943.80.
Conclusion: Severe pulmonary diseases determined the case mix of patients cared for in the Italian RICUs during the observed period. The Italian RICUs offer high quality assistance and are characterised by high mean weight per treated patient. However, the activity has been under-estimated due to the low sensitivity of the ICD9 classification system used in the recognition of the real disease and in the correct generation of relative DRG. The ICD9 classification system penalised the recognition of respiratory failure in particular.