Assessing dosing errors in legacy and low dose tip ENFit^® syringes

Area of Science:

• Medical Device Engineering
• Patient Safety
• Pharmaceutical Science

Background:

• Standardized ENFit® connectors aim to prevent misconnections in enteral medical devices.
• Concerns exist regarding potential dosing errors with low volume (≤2 ml) syringes utilizing these new connectors.
• Novel low dose tip (LDT) syringes were developed to address these specific concerns.

Purpose of the Study:

• To quantify unavoidable dosing errors associated with LDT syringes.
• To compare dosing accuracy between LDT and legacy syringes.
• To propose strategies for optimizing dose accuracy in enteral applications.

Main Methods:

• Computer-aided design (SolidWorks®) was employed to calculate dosing errors.
• Evaluated 0.5 ml and 1.0 ml LDT and legacy syringe connectors.
• Investigated the influence of delivery orientation, spillage, and flushing on dosing error.

Main Results:

• LDT syringes show a maximum ±5% dosing error (without medication in the moat) comparable to legacy syringes.
• With medication present and syringe reuse for flushing, LDT errors range from 1-18% (1.0 ml) and 28-35% (0.5 ml).
• Dosing errors increase with reduced syringe capacity and lower delivered volumes for both LDT and legacy types.

Conclusions:

• LDT syringe dosing errors can be reduced by clearing the moat area and using new syringes for flushing.
• Legacy syringe errors are minimized by upward connector orientation during disengagement and using new syringes for flushing.
• Both LDT and legacy syringe dosing accuracy are compromised by smaller volumes and specific usage scenarios.