Study of relationship between volume of distribution and body weight application to amikacin.

Amikacin use is difficult because of its narrow therapeutic and its pharmacokinetic variability. This variability of amikacin is not well known. To adapt amikacin the physician assumes that there is a linear and continuous relation between the volume of distribution and the body weight. The objective of our study was to evaluate the relationship between the volume of distribution (Vd) and the body weight (BW) using a non parametric statistical analysis of dependence so called Z method. Retrospective pharmacokinetic population study and statistic analysis. 872 patients receiving intravenous amikacin. The volume of distribution was modelled using the Non Parametric Adaptive Grid algorithm (NPAG) for a two-compartment model with intravenous infusion. Z coefficient was performed to evaluate the relationships between Vd and BW. For the 872 patients (mean age of 73 ± 17 years) dispatched as follow 53 % female and 47 % male, the analysis of the statistical relationships by the non parametric Z analysis showed a scattered linkage between Vd and BW. For the whole population, the relationship between Vd and BW was not linear (regression analysis). Z analysis demonstrated that only for 80 % of patients there is a relationship between Vd and BW. For these patients, regression analysis give a significant adjustment of a linear model (r = 0.47, p < 0.001). In the whole studied population there is not a continuous and linear relationship between Vd estimated by NPAG and the BW. These results underline the difficulties to adapt doses of amikacin with only BW information.

Relevance of fluoroquinolone use in a French teaching hospital.

OBJECTIVE: The objective of our study was to assess the good use of fluoroquinolone (FQ) in a French teaching hospital by a two round relevance review before and after proposal for better use of FQ prescriptions. PATIENTS AND METHODS: The relevance of FQ prescription according to regional guidelines was assessed using a standard card filled out retrospectively by physicians in the 3 previous months, in volunteer hospital wards. Then, two experts checked the relevance of prescriptions according to the regional antibiotherapy guidelines, a book called "Antibioguide", and determined a therapeutic index of adequacy for each card. The first survey (R1) took place in January 2008. The second survey (R2) took place in June 2009 to evaluate the impact of corrective measures, adopted at a meeting of the regional antibiotics commission in January 2009. RESULTS: Physicians in 18 wards completed 475 cards in R1 and physicians in 16 wards completed 263 in R2. The inappropriateness of FQ indication was significantly improved by 57% (P<0.001) between the two rounds and the rate of adequate cards was 33% in R1 and 55% in R2, giving an improvement of 66% (P<0.001). CONCLUSIONS: The improvement of FQ prescriptions and observance of guidelines demonstrate the importance of assessing the state of things before introducing corrective actions. "Antibioguide" was updated at the end of this study.

Stability study of amiodarone hydrochloride in capsules for paediatric patients using a high-performance liquid chromatography method.

Amiodarone hydrochloride, a class III antiarrhythmic agent, shows ß blocker-like and potassium channel blocker-like actions on the sinuatrial and atrioventricular nodes. It is given by mouth in the treatment of all forms of atrial, junctional and ventricular arrhythmias. Capsules for paediatric patients are not commercially available and must be prepared in the pharmacy department. The aim of the study was to evaluate the stability of amiodarone hydrochloride at different dosages, 10, 60 and 100 mg, in capsules for paediatric patients stored in three packages under dark conditions and at room temperatures over one year. At different intervals during the storage period, amiodarone hydrochloride concentration was tested using a high-performance liquid chromatography (HPLC) method. Amiodarone hydrochloride content remained greater than 95% of the initial concentration in all capsules at all dosages. The 10, 60 and 100 mg amiodarone paediatric capsules were stable for one year when stored in the three packages at ambient temperature and under dark conditions.