[Automation of parenteral nutrition elaboration: adaptation to in force legislation]

Quality and efficiency criteria of allowances associated to technological procedures are developing in a setting that values quality, and from there the Real Decree RD175/2001 has been issued by which the rules of correct elaboration and quality control of formulations and pharmacy preparations. Parenteral nutrition (PN) is a formulation and, as such, its elaboration and control have to agree with the in force regulations. With this aim, at the Bellvitge University Hospital we have developed a project for automation of elaboration of PN mixtures with the MicroMacro Pump 23 Baxa Compounder.

To assess the impact of implementing an automated system of volumetric control in PN elaboration.

The project development may be divided into two differentiated aspects. The first one consisted in the implementation and optimization of the automated system of volumetric control (ASVC). The second aspect comprehends the comparative control performed between the new system and the previous one, and which consisted of a gravimetric system with visual control. For that, real weights were gathered and were compared to predicted weights, and the time of elaboration per bag before and at two times after the implementation of the automated system was registered; the first time just after implementation of the system, and the second time within one year.

For the comparison study between both systems used, 141 preparations in total, corresponding to individualized PN, were analyzed: 47 elaborated by means of the gravimetric system (GS), 47 with the ASVC during the implementation period (PN ASVC period 1), 47 PN elaborated with the ASVC within one year of implementation (PN ASVC period 2). The average variation between real weight and predicted weight at the three periods (pre-ASVC, NP ASVC period 1, NP ASVC period 2) was 2.41%, 1.35% and 1.25% respectively (table I). This decrease was statistically significant (p = 0.014). When analyzing the percentage of preparations out of the 3% variation range, we observed a significant reduction (p = 0.00001) by comparing the three periods (Table II). The average elaboration time with the ASVC increased approximately in 4 minutes by bag (3 min 58 sec) during the first studied period, and 3 min 10 sec during the second period, as compared with the study period with the GS.

The new bag-filling system by means of volumetric control represents an improvement in accuracy control and a decrease in the risk for surpassing the acceptable limits. The implementation of a new technological procedure is a difficult task that implies the change of many aspects of the daily practice and that requires a "cultural" change in the PN Unit with the aim of optimizing the process. However, these issues allow for an adaptation to legal requisites in force regarding the regulations of proper elaboration and quality control of formulations as well as an improvement in the integral quality of care.