[Is the Relative Complexity Index beta an accurate indicator of the cost of anesthesia?]

In order to assess the medical activity and the related costs, the French Ministry of Health has designed a relative value scale for medical procedures, the Relative Complexity Index (RCI). The RCI for anaesthesiology, called BETA, is the result of the combination of four subindexes: T for the type of anaesthesia, D for the duration, C for the related surgical procedure, and EG for the patient's status according to the ASA scale. The goal of this study has been to test whether the BETA index was actually an acceptable indicator of the direct cost of an anaesthetic. We have determined the cost of 248 procedures in a teaching hospital and achieved a statistical analysis of the relationship between costs, RCI and the various subindexes. The mean cost of an anaesthetic was 1,205 FF (SD = 1,325), 61.4% of which being for salaries. The cost of a general anaesthetic was 2.5 times higher than the cost of a local/regional anaesthesia procedure. Mean cost was around 700 FF for ENT, urology, gynaecology and obstetrics, 1,200 FF for orthopaedia and visceral surgery, and 5,130 FF for cardiac surgery (not including the equipment for extracorporeal circulation). A strong positive relation was found between the BETA and cost (r = 0.90, p < 10(-4)). The best predictive model of cost was log-linear, using only the duration, the type of anaesthetic and the related surgical procedure. The patient's status was not a significant factor, nevertheless in our sample, ASA 4 patients had a significantly higher cost than others (p = 0.0004, Mann & Whitney test).(ABSTRACT TRUNCATED AT 250 WORDS)