Background Parenteral drug administration plays an important role in hospitals. It is well known that a certain amount of a drug remains at the end of the infusion and is not administered to the patient because of the dead volume: this dead volume could be the origin of an underdosing.

Purpose The aim of this study is to determine the dead volume of the injectable delivery system including the serum bag, perfusion tubulure, syringe and short catheter used for the reconstitution and administration of injectable drugs, and its impact on variation of the prepared doses.

Material and methods We weighed, using an analytical balance, all the medical devices (serum bag, perfusion tubulure, syringe and short catheter) used in the administration of an injectable drug before and after the passage of an antibiotic solution. We can thus determine the dead volume remaining in each material. Statistical analysis were performed with SPSS 13. 0.

Results The table shows that the dead volume differed between medical devices (p<0.001). It was significant for the serum bag and perfusion tubulure, and low for syringes and short catheters. The overall dead volume is estimated at 4.5±1.7 mL.

Conclusion A considerable amount of the infusion volume, and therefore of the antibiotic, depending on the concentration, is lost at the end of the infusion due to the dead volume depending on the medical devices used as demonstrated in this study and in other studies.¹ Loss of a potential amount of a drug can constitute a problem regarding safety and efficacy of therapy, especially for drugs with narrow therapeutic margins. This is especially important for the serum bag and perfusion tubulure, where the dead volume is about 2.61 mL and 1.74 mL respectively.

References and/or Acknowledgements 1. Cheikh A, Rhali Y, Mefetah H, Sbai I, Mojemmi B, Draoui M, Bouatia M. The influence of the dead volume of the closed system (spike–connector–syringe) on the reconstitution of injectable drugs. Eur J Hosp Pharm24(1):A214–A216.

No conflict of interest