VALUTAZIONE MEDIANTE METODOLOGIA BOTTOM UP E MICRO-COSTING DEGLI EXTRACOSTI GENERATI DALLE INFEZIONI CORRELATE ALLE PRATICHE ASSISTENZIALI IN AMBITO ORTOPEDICO.

Healthcare-associated Infections (HAIs) in Europe account for around 16 million additional patient-days in hospital per year (an average of 4 days per infection), with around 37,000 deaths associated with the infection itself .The total estimated annual cost of hospital-acquired infections for Europe is 7 million euros (ECDC, 2008). Surgical Site Infections (SSIs) account for between 15% and 25% of all HAIs, ranking third in order of frequency (Bozic et al, 2005). SSIs resulting from joint replacement operations are serious complications both from the patient’s and from an economic point of view. The onset of an SSI is associated with increased morbidity and mortality rates and thus leads to added costs for the National Health Service in terms of prolonged hospital stays (De Lissovoy et al, 2009), related diagnostic procedures and possible revision surgery (Perencevich et al , 2003). It is estimated that the onset of an SSI following orthopaedic surgery doubles the risk of re-admissionsin the following 12 months and that the direct costs of hospitalisation account for more than double ( Broex et al 2009). The cost of revision surgery for an infected hip replacement is 2.8 times higher than a non-septic revision and 4.8 times higher than the original implant (Bozic et al, 2005). The aim of this study is to develop a model for analysing healthcare expenditure borne as a result of the occurrence of Surgical Site Infections (SSIs) in patients undergoing hip and knee replacement surgery. The study was conducted at the Gaetano Pini Orthopaedic Institute. Selection of the patients took place within the framework of the ISChIA project on active prospective surveillance among patients who had experienced a SSIs. This aim was achieved by developing a model (Phase I) for evaluating the impact of SSIs – as defined by the CDC – on healthcare expenditure, which considers both the perspective of the hospital providing the treatment and that of the Regional Health Service. Direct extra costs were analysed from the perspective of the healthcare provider, using bottom-up and micro-costing methods; these estimated costs include the direct variable costs (resources used for specific patient services) of treating the infection borne within the hospital, including treatment costs, laboratory costs, diagnostic examinations, x-rays and consultation costs Given a case of hospitalisation with SSI, the hospital meets the direct costs arising therefrom, which would otherwise not have been generated. At the same time, the Regional Health Service, in addition to these costs, must meet any costs relating to new cases of patients being admitted as due to SSI. The model thus implemented was then subject to validation during Phase II. The average additional value estimated for managing SSI is €4,905 in Phase I and €4,155 in Phase II. ECDC. Focus on healthcare-associated infections, Annual epidemiological report 2008. De Lissovoy, G.; Fraeman, K.; Hutchins, V. et al. ‘Surgical Site Infection: Incidence and Impact on Hospital Utilization and Treatment Costs’, American Journal of Infection Control. 2009; 37(5):387-97. Perencevich, E.N.; Sands, K.E.; Cosgrove, S.E. et al. ‘Health and Economic Impact of Surgical Site Infections Diagnosed after Hospital Discharge’, Emerging Infectious Diseases. 2003; 9(2):196-203. Broex, E.; Van Asselt, A.; Bruggeman, C.A.; Van Tiel, F.H. ‘Surgical site infections: how high are the costs?’, The Journal of Hospital Infection. 2009; 72(3):193-201. Bozic, K.J.; Ries, M.D. ‘The impact of infection after total hip arthroplasty on hospital and surgeon resource utilization’, J Bone Joint Surg Am. 2005 Aug; 87(8):1746-51