Protecting healthcare workers and patients from inadvertent exposure when handling Cytotoxic drugs is a high priority in hospitals
Cytotoxic drugs are increasingly being used for the treatment of cancer and other medical conditions such as rheumatoid arthritis. These drugs are known to be highly toxic to cells and are potential mutagens. To protect healthcare workers and patients from inadvertent exposure is a high priority.
In our hospital all cytotoxic preparations for cancer wards are centralised at the Pharmacy department with pharmaceutical responsibility, in a cleanroom (class C) with laminar air-flow Biological Safety Cabinets (BSC’s-class A). Nevertheless, syringes of methotrexate prescribed for ectopic pregnancy are prepared by nursing staff in the Gynaecological Emergency unit without specific safety measures (neither BSC’s nor isolators). For this indication a 1 mg/kg single-dose methotrexate is administrated by intramuscular route. At this time, there is no ready-to-use dosage form such as pre-filled syringes that are marketed. To address this issue, the first measure was to prepare in the centralised cytotoxic preparation unit medications prescribed during opening hours. But about one hundred methotrexate syringes are prescribed yearly out of these hours. We decided not to prepare ready-to-use syringes because we just have the agreement for magistral preparations. The second corrective measure was to determine and then implement on the ward a safe drug-transfer device, in order to prevent and reduce cytotoxic contamination of the workplace and thus ensure the safety of staff involved in handling.
Therefore we undertook this study to assess medical devices available for the secure handling and administration of cytotoxic drugs. We purchased a system with a vented vial access to avoid aerosolisation and with a luer lock syringe adaptor that allows connection with an intramuscular needle for administration.
We selected and tested three drug-transfer devices usually referred to as “closed-system”: PhaSeal system (Carmel Pharma), Spiros system (Hospira) and Texium system (CareFusion, formerly Cardinal Health). As a first step, a pharmaceutical evaluation was conducted based on the devices specifications supplied by the manufacturers and on practical experiments (including a fluorescein test). This evaluation was completed by an estimate of extra cost that would be required by the use of such devices.
As a second step, a technical assessment was performed by nurses on the ward, simulating a preparation, after training and instructions were provided by a pharmacist. Then nurses were given a questionnaire with ten criteria to evaluate packaging (labelling, opening), handling and safety, with an overall rating out of 10.
For all experiments, empty drug vials filled with 2 ml of fluorescein (a fluorescent indicator) and sealed with drug vial septum caps were used.
These three systems have a similar needle free valve system and can be directly connected to a needle for drug administration, which reduces exposure of healthcare workers during handling and administration.
According to the literature Phaseal is the only device that satisfies the definition of a closed system. It is able to capture hazardous drugs leakage and vapours. However, our pharmaceutical practical assessment led us to discard this system. Indeed handling this system was not very intuitive and the low frequency of syringe preparations (less than one per month per nurse) likely lead to misuse. Thus, only the SpirosTM and Texium systems, which require less training, were tested, first by pharmacists and then by nurses on the ward.
The pharmacists assessed the contamination of the connections thanks to a test with fluorescein. For both devices, manipulation under UV light during the simulation of a preparation showed a dry connection without fluorescein spot between the vial access device and the syringe connector.
According to the safety device, the change to this new device would generate an over cost for our hospital of 65 % for the Spiros system, 90% for the Texium system and 220% for the Phaseal system compared with the traditional needle/air vent. This estimation only takes into account the price of the devices and of the cytotoxic drug.
In the Gynaecological Emergency unit, four nurses (half the potential methotrexate handlers) tested on the same day these two devices, simulating the preparation of a drug syringe with each drug-transfer device. They all felt very involved and filled out one questionnaire for each device, that is eight in all. Regarding all criteria, all the nurses found the Texium device more efficient than the Spiros system. It was considered easier to handle and safer. Indeed they reported two significant benefits: the SmartSite (Texium technology) vial access device enables the easy removal of the entire low-level drug solution and above all is kept perfectly connected to the vial whereas Clave vial access spike (Spiros technology) is unsteady. CareFusion’s (formerly Cardinal Healthcare) device was given a ten out of ten global mark whereas Hospira’s device was given a five out of ten.
None of safe drug transfer devices marketed is both easy-to-use and a perfect barrier against hazardous drugs leakage. But they enable to considerably reduce environmental contamination by cytotoxic drugs during handling and administration. It’s an interesting concept for preparation in wards without safety specific measures but also in BSC’s of the centralised cytotoxic preparation unit, at the Pharmacy department, for the reconstitution and the preparation of all hazardous drugs in syringes. Safety benefits provided overtake their higher cost compared with traditional devices, expecting that their larger use will make decrease their price.
At the end of our study, the Texium system seems to be the best compromise between safety requirements and ease of handling, and the most adapted to our issue. But we are aware that this device is not a real “closed-system” according to studies already published because it may not prevent the release of drug vapours.
In practice, before implementation in the Gynaecological Emergency unit, we met problems with Texium system used in real conditions. We observed with vials of methotrexate (Sanofi) leakage of cytotoxic at vial septum level when setting up SmartSite vented vial access device (four times out of six trials). It seems to be a problem of overpressure in the vial, but this effect was not expected. So both devices and vials are being assessed by manufacturers to find the reasons of this
big issue. Waiting for the results of these evaluations, this system has not yet been implemented on the ward. Consequently, we are now extending this study to the Tevadaptor system (Teva Medical Device), which concept is similar to Phaseal one.
1. American Society of Health System Pharmacists. ASHP guidelines on handling hazardous drugs. Am J Health-Syst Pharm 2006,63:1172-93.