|
Prospective, randomized, double-blind trial comparing teicoplanin and cefazolin as antibiotic prophylaxis in prosthetic vascular surgery |
Marroni M, Cao P, Fiorio M, Maghini M, Lenti M, Repetto A, Menichetti F |
|
|
Record Status This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. Health technology The use of prophylactic antibiotics to prevent wound and graft infections in patients following prosthetic vascular surgery.
Economic study type Cost-effectiveness analysis.
Study population Patients who underwent abdominal aortic and lower extremity peripheral vascular surgery who had received no anti microbial treatment in the five days prior to surgery, who had no pre-operative areas of wet gangrene, cellulitis or open ulcer and no history of allergy to cephalosporins or glycopeptide antibiotics. The mean age of patients in the teicoplanin group was 68+/-9 years and in the cefazolin group was 70+/- 8 years.
Setting Hospital. The economic analysis was conducted in Perugia, Italy.
Dates to which data relate Effectiveness and resource data were collected between May 1995 and April 1997. The price years used were not stated.
Source of effectiveness data Effectiveness data were derived from a single study.
Study sample The study sample was taken from all patients during the two-year study who were to undergo peripheral vascular surgery. Power calculations do not appear to have been used to determine sample size. There were 238 patients randomised equally between the teicoplanin and cefazolin treatment groups.
Study design The study was a single centre double blind randomised controlled trial. The duration of follow up was until one year after hospital discharge, with a mean length of follow up of 24 months (range: 12 - 36 months). Subjects were allocated between groups using block randomisation. There was no loss to follow up.
Analysis of effectiveness The analysis of effectiveness was based on intention to treat. The primary health outcomes were the rate of prosthetic and wound infections. Secondary outcome measures included mortality and side effects. At analysis both groups were shown to be similar in demographic and clinical characteristics, and operative procedures performed in the two groups were also similar.
Effectiveness results There were no significant differences in infection rates in the two groups.
7 patients (5.9%) in the teicoplanin group developed infections, compared with 2 (1.7%) in the cefazolin group.
Mortality rates were also similar: 4 (3.4%) in the teicoplanin group compared with 3 (2.5%) in the cefazolin group, and no side effects were observed in either group.
Clinical conclusions Both drugs have similar levels of effectiveness and tolerability.
Modelling Costing was undertaken prospectively using the same patient sample as used in the effectiveness analysis.
Measure of benefits used in the economic analysis Since the clinical analysis demonstrated that there were no significant differences between the two interventions, the economic analysis was based on the difference in costs only.
Direct costs The direct costs of drug therapy and hospital stay were included in the analysis. Acquisition costs of antibiotics were estimated to be $8.69 for cefazolin 2g and $39.83 for teicoplanin 400mg, with the cost of one day of hospital stay being $294. It is unclear how these unit costs were determined. The price years used do not appear to have been stated, and the currency conversion rate (if original estimates were in Italian lira) was not stated. The perspective adopted was not stated, but appears to have been that of the Italian National Health Service. Discounting was not used (or relevant) in the analysis. Resources used were reported separately from costs. Adverse events were considered in the analysis.
Statistical analysis of costs No statistical analysis of costs was undertaken.
Indirect Costs Indirect costs were not included.
Sensitivity analysis No sensitivity analysis was carried out.
Estimated benefits used in the economic analysis Not applicable due to the cost-minimisation analysis carried out.
Cost results The cumulative total cost for the teicoplanin group was estimated to be $571,572 compared with $519,062 for the cefazolin group, a difference of $52,510. Both drug and hospital stay costs were higher in the teicoplanin group. Overall total hospital stay was higher in the teicoplanin group, 1,928 days, compared with 1,762 days for the cefazolin group. 90 of these additional 166 days were for treatment of infectious complications.
Synthesis of costs and benefits Authors' conclusions Cefazolin is as effective and less costly than teicoplanin and therefore should remain the most appropriate choice for prophylaxis in patients undergoing vascular surgical procedures.
CRD COMMENTARY - Selection of comparators A justification was provided by the authors for the comparator used, namely that cefazolin was a widely used antibiotic regimen for post surgical infection prevention. You, as a user of the database, should decide if this is a widely used health technology in your own setting.
Validity of estimate of measure of benefit The analysis was based on a double blind randomised controlled trial, which was appropriate for the analysis, producing results of high validity. The study sample appears to have been representative of the study population, and both patients groups were shown to be comparable at baseline analysis. Power calculations were not used to determine sample size. The clinical analysis demonstrated that both treatments had therapeutical equivalence and therefore the economic analysis was based on the difference in costs only.
Validity of estimate of costs The primary focus of this paper was on clinical effectiveness and little information was therefore included on the cost analysis. The study appears to have been conducted from the perspective of the National Health Service, but it is difficult to determine if all relevant costs from this perspective were included in the analysis. Costs associated with follow up, which would have been similar in both groups, have been excluded from the analysis. Length of hospital stay was reported separately from costs in the analysis. Although resources used were taken directly from the trial, it is unclear where prices were obtained. These prices were reported in US dollars, but no currency conversion rate from Italian lira was given. The price years used in the analysis do not appear to have been stated. Discounting was not used in the analysis, which is probably appropriate as all costs appear to have been incurred within a one year time period.
Other issues The generalisability of the authors' conclusions was not discussed in the paper, and the economic results of the study do not appear to have been compared with those in other studies.
Implications of the study The results of this study support the choice of Cefazolin for prophylaxis in clean vascular surgery.
Bibliographic details Marroni M, Cao P, Fiorio M, Maghini M, Lenti M, Repetto A, Menichetti F. Prospective, randomized, double-blind trial comparing teicoplanin and cefazolin as antibiotic prophylaxis in prosthetic vascular surgery. European Journal of Clinical Microbiology and Infectious Diseases 1999; 18(3): 175-178 Indexing Status Subject indexing assigned by NLM MeSH Aged; Anti-Bacterial Agents /economics /therapeutic use; Antibiotic Prophylaxis /economics; Blood Vessel Prosthesis Implantation; Cefazolin /economics /therapeutic use; Cephalosporins /economics /therapeutic use; Comparative Study; Costs and Cost Analysis; Double-Blind Method; Female; Humans; Italy; Male; Middle Aged; Prospective Studies; Surgical Wound Infection /prevention & Teicoplanin /economics /therapeutic use; control AccessionNumber 21999006892 Date bibliographic record published 31/05/2001 Date abstract record published 31/05/2001 |
|
|
|