# Excess volume addition method improves human resource efficiency and environmental sustainability of cytotoxic drug preparations

## TL;DR

Using half-filled bags with excess volume improves efficiency and reduces waste in preparing cancer drugs.

## Contribution

A new method using half-filled bags reduces preparation time and waste for cytotoxic drugs.

## Key findings

- The excess volume addition method reduced preparation time by 24% compared to the volume substitution method.
- The new method saved 9.8% of a full-time equivalent technician's time over six months.
- The excess volume addition method decreased cytotoxic waste by 2.21% annually.

## Abstract

The increasing incidence of cancer entails a rising burden of cytotoxic drugs preparation. To improve the preparation process of cytotoxic drugs, specially designed half-filled bags with overfill capacity were manufactured and used in clinical routine. The aim of this study was to investigate the impact of using such bags on the duration of preparation, human resources, costs and environmental sustainability.

A retrospective study comparing two methods, volume substitution and excess volume addition, for cytotoxic drug preparations was conducted over two periods of 6 months, within a University Hospital chemotherapy production unit. Volume substitution method (period 1; 5527 preparations) corresponded to the use of filled-bags. Excess volume addition method (period 2; 5108 preparations) corresponded to the use of half-filled bags. Preparation time included drug reconstitution and gravimetric controls. Data were extracted from the BD CatoTM database.

Median duration of preparation using the excess volume addition method (2.4 min; IQR: 1.9–3.2) was significantly shorter than the volume substitution method (3.2 min; IQR: 2.6–4.1; p < 0.0001). It allowed saving 67 h during period 2, corresponding to 9.8% of a full-time equivalent technician. However, mean cost per preparation was significantly increased by 58% when using the excess volume addition method (p < 0.0001), due to higher costs of the newly designed bags. Broken down over the course of a year, the excess volume addition method would decrease the weight of cytotoxic waste for the entire hospital by 2.21%.

Using the excess volume addition method with half-filled bags decreases time preparation, consumables and waste related to cytotoxic drug preparation.