Closed Systems vs. CSTDs

Closed Systems

CSTDs

Definition

While all CSTDs are classified as closed systems, not every closed system is a CSTD. The National Institute for Occupational Safety and Health, (NIOSH) defines them as follows:

 

Examples of each include:

Primary engineering controls: Biological safety cabinets (BSCs), Compounding Aseptic Containment Isolator (CACI), Restricted Access Barrier System (RABS)

Secondary engineering controls: Negative Pressure Room, Cleanrooms, HEPA filters

Supplementary engineering controls: CSTDs

Closed System Transfer Devices (CSTDs)

 

A closed system transfer device, or CSTD, is a drug transfer device that mechanically prohibits the transfer of environmental contaminants into the system and the escape of hazardous drug or vapor concentrations outside the system.

 

/CSTDs are used in compounding and administration

/CSTDs prevent exposure throughout the hazardous drug lifecycle

/ CSTDs are designed to prevent drug aerosolization, leaks, and drips

/ CSTDs are designed to prevent accidental disconnections

Learn more about EQUASHIELD CSTDs

Complete Your Protection

Multiple Layers of Protection Close the Gaps

Types of Engineering Controls

primary, secondary, and supplementary engineering controls

USP <800> recognizes that engineering controls are divided into 3 category levels of control including:

definition of engineering control for primary, secondary, and supplementary controls

Types of Engineering Controls

Engineering controls that qualify as closed systems

Biological Safety Cabinet (BSC)
Isolator

Biological Safety Cabinets (BSC) | Compounding Aseptic Containment Isolator (CACI)

 

/ According to USP <797> primary engineering controls are required to protect the preparation from cross contamination and microbial contamination

/ According to USP <797> primary engineering controls are a closed system

/ Primary engineering controls for containment include BSCs (biological safety cabinets), and isolators, also known as compounding aseptic containment isolators (CACIs)

/ Don’t protect from contamination that can leave residue within the primary engineering controls

/ Don’t protect contamination throughout lifecycle

 

/ USP <800> defines supplemental engineering controls as controls that offer an additional level of protection during compounding & administration

/ According to NIOSH CSTDs are a closed system

/ Closed System Drug-Transfer Devices (CSTDs), are the only engineering control designed to prevent vapor release, spills, leaks, and needlesticks

/ NIOSH defines CSTDs as systems that mechanically prevent environmental contaminants from entering and hazardous drugs from escaping

/ CSTD components include needle free syringe units, IV tubing sets, spike adaptors, vial adaptors, female connectors, luer lock adaptors, and additional accessories

/ Peer-reviewed studies confirm that mechanical-based technologies are more effective in preventing drug aerosolization


Clinical Studies Reveal High Contamination in without CSTDs

Contamination remains a frequent issue with Isolators and BSCs. In an HMP contamination study, 75% of pharmacy area samples were wipe sampled and found to be contaminated.1

Study #1

Isolator Contamination Reduction

Using a CSTD in the isolator cut HMP contamination by more than half compared to a needle and syringe2

A study was conducted comparing CSTDs to traditional compounding devices (syringe and spike) using 10 antineoplastic agents to assess the effectiveness of CSTDs in reducing HMP contamination on the surfaces of Aseptic Isolators in real-world practice. Over a six-month period, 686 surface samples were collected from gloves, the inner surface of the Aseptic Isolators window, and the worktop. Results showed that average contamination rates in standard Aseptic Isolators was 26.39%. Introducing a CSTD reduced average contamination to 12.24%. The contamination rate was lower with CSTDs compared to standard devices.

In both groups, gloves were the most contaminated surface. With standard devices, average contamination rates were 33.1% for gloves, 24.2% for windows, and 21.9% for worktops. The rates were drastically reduced with the introduction of CSTDs – 16.0%, 10.4%, and 10.0%, respectively. With a p-value of <0.0001, this study is highly statistically significant and confirms that CSTDs significantly decrease the chemical contamination of Aseptic Isolators compared to standard compounding devices.

Isolator Contamination Reduction

Using a CSTD in the isolator drastically cut HMP contamination.3

 

isolator Contamination Reduction with CSTD use 

 
In order to assess the effectiveness of CSTDs, this study investigated the surface contamination arising from the preparation of five anticancer drug infusions in a pharmaceutical isolator and compared use of a conventional syringe and needle technique with a CSTD.

All surfaces sampled during baseline, including external surfaces of infusions and syringes, were contaminated with each marker drug. During the intervention phase, isolator surfaces were free from detectable contamination and the contamination measured on gloves, preparation mats and surface of infusions was markedly reduced. The frequency of contamination on syringe and infusion surfaces was also lower.

Surface contamination from cytotoxic infusion preparation in a pharmaceutical isolator was significant and could transmit cytotoxic residues to patient and public areas via infusion surfaces. The frequency and amount of contamination were reduced by the CSTD.

BSC Contamination Reduction

Using a CSTD in the BSC drastically cut median values for surface HMP contamination compared to standard syringes.4

 

 

 

 
During a test across 22 hospitals, contamination with cyclophosphamide, ifosfamide, and 5-fluorouracil was measured on four surfaces using standard preparation techniques and a CSTD. Standard preparation showed high contamination levels, with 78% of samples testing positive for cyclophosphamide, 54% for ifosfamide, and 33% for 5-fluorouracil, with BSC airfoils being the most contaminated. Using a CSTD significantly reduced contamination, with positive samples dropping to 68%, 45%, and 20%, respectively, and median contamination levels decreasing by up to 95%

Median values for surface contamination with cyclophosphamide, ifosfamide, and 5-fluorouracil were reduced by 95%, 90%, and 65%, respectively.

CSTDs are Functionally Different than Primary Engineering Controls

CSTDs are the only engineering control designed to prevent spills, leaks, and needlesticks in addition to providing extra vapor protection.

EQUASHIELD vial + cstd drawing

Filling in the Gaps

CSTDs are the only engineering control designed to prevent spills, leaks, and needlesticks in addition to providing extra vapor protection.

EQUASHIELD vial + cstd drawing

Preventing HMP Exposure Throughout the Lifecycle

CSTDs are uniquely effective in preventing occupational exposure for workers in administration and throughout the whole life cycle of HMPs, whereas the use of compounding aseptic containment isolators and biological safety cabinets are used in the preparation of HMPs in the pharmacy.5

HMP Lifecycle

A closed system must be used at every stage of the lifecycle. CSTDs are uniquely effective in preventing occupational exposure for workers in administration and throughout the whole life cycle of HMPs, whereas the use of isolators and BSCs are used in the preparation of HMPs in the pharmacy.5
hazardous drug exposure throughout the lifecycle, storage, preparation, transport, administration, disposal

Pharmacists Understand They Are Safer Using CSTDs

 545 chief pharmacists across Europe surveyed responded:5

Pharmacists #1 Choice

EQUASHIELD CSTDs Eliminate Surface Contamination Risk

EQUASHIELD CSTDs are clinically backed to be the most closed 6

EQUASHIELD CSTD Study

A study found that implementing the EQUASHIELD CSTD significantly reduced surface contamination compared to using a conventional syringe with a BSC. Wipe samples taken from common high-contact areas, such as dispensing counters, door handles, and floors, frequently showed contamination levels above safe concentrations.    

                   No CSTD + BSC     

However, the introduction of the EQUASHIELD CSTD effectively eliminated cytotoxic agent contamination in both preparation and administration areas within the ambulatory cancer chemotherapy infusion center. This study demonstrates that using EQUASHIELD CSTDs effectively minimizes contamination throughout the HD lifecycle.

      CSTD + BSC

Knowledge is Power

Pharmacists and nurses can safeguard their health by ensuring they are using the appropriate closed systems

Learn More About CSTDs

Protect yourself with safer practices by empowering yourself with the facts. Where procedures mandate the use of closed systems, CSTDs must be used alongside primary and secondary engineering controls. They each serve distinct purposes, working together to ensure the safe handling of HMPs.

References:

  1. Clark, B. A., & Sessink, P. J. M. (2013). Use of a closed system drug-transfer device eliminates surface contamination with antineoplastic agents. Cleveland Clinic Cancer Center, Fairview Hospital, USA
  2. Connor T, et al. Am J Health- Syst Pharm. 1999; 56(14): 1427-1432
  3. Simon N, et al. PLoS One. 2016; Jul 8: 11 (7): 1-17
  4. Vyas N, et al. JOncolPharm Practice. 2016; 22(1):10-19
  5. Lindsley, I., & Musu, T. (2022). The ETUI’s list of hazardous medicinal products (HMPs). European Trade Union Institute, Brussels.  https://www.europeanbiosafetynetwork.eu/wp-content/uploads/2022/10/The-ETUIs-list-of-hazardous-medicinal-products-HMPs_2022.pdfhttps://www.stopcanceratwork.eu/wp-content/uploads/2020/10/ETUI-Briefing-Note-HMP-CMD4.pdf
  6. https://www.equashield.com/eq-academy/resources/infographic/

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