A Modified Potency Test Strategy for IV Admixtures Prepared by Robotic Systems
Introduction: Robotic systems are increasingly used for compounding sterile IV admixtures (1-5). In addition to routine gravimetric checks, initial and periodic drug potency analysis by high-performance liquid chromatography (HPLC) is desired to verify the system accuracy. However, the conventional HPLC test procedures often result in unexpected failures (1-2). This study was initiated to develop a modified HPLC test strategy to eliminate the common source of variability and focus the effort on the accuracy of robotic system.
Automated preparation of chemotherapy: quality improvement and economic sustainability.
PURPOSE
The quality and economic implications of manual versus automated preparation of antineoplastic drugs were compared.


METHODS
This four-week study evaluated 10 routinely used antineoplastic drugs (fluorouracil, cyclophosphamide, gemcitabine, trastuzumab, bevacizumab, oxaliplatin, cisplatin, paclitaxel, irinotecan, and etoposide) prepared by manual and automated procedures. The accuracy of the dose of the active ingredient was calculated in terms of percent relative error for the difference between the nominal value indicated on the prescription and the actual value of the drug in the finished product. A comparative economic analysis of the manual and automated preparation procedures was performed by calculating the mean unit cost for each preparation at different production levels. Participating pharmacists and technicians completed a survey rating each preparation method in terms of performance, operator satisfaction, technology, and safety.


RESULTS
Of the 2500 i.v. antineoplastic preparations made in the pharmacy during the four-week study period, 681 were analyzed (348 using the automated procedure and 333 manually). Of these, 17 varied by more than 5% of the prescribed dose, and 1 varied by over 10%. Accuracy, calculated in terms of average percent relative error, was the highest and lowest during manual preparation. The preparation time for individual drugs was always higher when prepared using the automated procedure. A lower mean variable unit cost was observed for preparations made using the automated procedure. Questionnaire results revealed that operators preferred the automated procedure over the manual procedure.


CONCLUSION
Both the automated and manual procedures for preparing antineoplastic preparations proved to be accurate and precise. The automated procedure resulted in substantial advantages in terms of quality maintenance standards and risk lowering.
Thermal-mechanical fully coupled analysis of high-speed angular contact ball bearings
The thermal and mechanical properties of angular contact ball bearings are critical to their operating accuracy and service life. On the basis of the theory of dynamics and frictional heat generation, this work establishes a thermal-mechanical fully coupled model. The high-speed motion characteristics, temperature, and dynamic stiffness are analyzed, and the simulation results are compared with the theoretical calculation and experimental results. Then, the temperature and axial deformation of the bearings under different rotation speeds are analyzed, and the laws of mechanical and thermal characteristics of the bearings are obtained. Results show that an increase in the rotation speed of the inner ring causes the temperature of each component to increase, with the contact area of the balls showing the greatest increase in temperature. An increase in rotation speed also increases the axial deformation of the inner ring.