Content authored by Kasey Smith, PharmD, Clinical Oncology Pharmacist
Closed System Transfer Devices –
What are they? Why do Thompson Oncology Group’s Pharmacists and Techs use them?
To begin this discussion, and to understand how the Oncology Pharmacists’ and Techs’ use of CSTD impacts care, we must answer a different question: What are hazardous drugs?
If something is labeled as hazardous, it is dangerous, can be harmful, and probably should be avoided. We typically associate medications with helpfulness, as drugs we use to help us be well. Sometimes medications can do both, harm and help.
Medications are considered “hazardous” if they possess one of the six characteristics listed below.
Characteristics of a Hazardous Drug:
Why would anyone use these hazardous drugs? In short, to fight cancer.
Chemotherapy, a term that describes multiple cytotoxic drugs used to treat cancer, meets all of these criteria. (Cytotoxic means a drug prevents cells from reproducing or causes cells to die because it contains chemicals that are toxic to cells.) When chemotherapy is administered to a patient the risks of it doing harm are outweighed by its ability to fight and potentially cure cancer. However, if healthcare workers have unintentional prolonged exposure to these medications they may suffer adverse health-related consequences.
According to the CDC and The National Institute for Occupational Safety and Health, “About 8 million U.S. healthcare workers are potentially exposed to hazardous drugs, including pharmacy and nursing personnel, physicians, operating room personnel, environmental services workers, workers in research laboratories, veterinary care workers, and shipping and receiving personnel.” (Retrieved from https://www.cdc.gov/niosh/topics/hazdrug/default.html on 10/1/2021)
So how can this type of exposure happen?
At Thompson Oncology Group, chemotherapy is compounded by pharmacy personnel.
A simplified explanation of the compounding process is as follows: Pharmacy personnel transfer, and in some instances reconstitute, the chemotherapy at patient-specific doses typically from the vial supplied by the manufacturer to another vessel. This vessel is usually a bag of fluid confirmed to be compatible with the drug or a syringe used to administer the medication to a patient.
This compounding process is completed in a sterile environment using an aseptic technique. During these manipulations, chemotherapy drugs have the potential to release hazardous vapors into the air if the technique is not done correctly. These vapors put the pharmacy personnel at risk for exposure and possible adverse health effects. Pharmacy is not the only department affected. Nurses also face the risk of exposure to vapors when administering these medications to patients.
(To learn more about Sterile Pharmacy read this blog: Pharmacy Technicians: The Unseen Impact on Patient Care)
Exposure to hazardous medications can cause both acute and chronic health effects such as skin rashes, adverse reproductive outcomes, and even possibly cancer. The health risk to a healthcare worker depends on how toxic the drugs are the amount of exposure they have. One way to protect workers from these dangerous exposures is through the use of engineering controls.
Thompson Oncology Group has implemented several of these engineering controls to protect its employees and patients. A few examples include negative pressure rooms, Biological Safety Cabinets, and Personal Protective Equipment (PPE). A fairly new engineering control that has been implemented is Closed System Transfer Devices (CSTD).
Now we can answer the question: What is a CSTD?
A CSTD is a drug transfer device that prohibits the escape of the hazardous drug and its vapor concentrations into the surrounding air. CSTDs consist of multiple pieces that work together to form a system. The system uses an air-cleaning technology to prevent the escape of hazardous medications into the work environment. When used appropriately it offers enhanced protection against potential exposures.
Here is an interesting video on an example of a Closed System Transfer Device.
At Thompson Oncology, CSTDs are used by both nursing and the pharmacy department when handling chemotherapy. The devices protect the pharmacy personnel compounding the chemotherapy by preventing the release of vapors from the drug and by reducing the potential of an accidental drug spill. Once compounding is complete the nurses administer the chemotherapy to patients through a CSTD which serves to protect them in the same manner.
When used appropriately, CSTD along with the other aforementioned engineering controls provides healthcare workers with a sense of protection from hazardous medications. Protecting employees while maintaining the sterility of the chemotherapy prepared for patients is of utmost importance for everyone at Thompson Oncology.