Table 1.
Description of Error Types and Impact
| Error type | Description of error | Impact of error | Workflow differences |
|---|---|---|---|
| Used partial vial errors | |||
| Used partial vial not used when available | Failure to use a used partial vial (ie, drug vial containing leftover medication) that is within its use date | Unnecessary and costly drug waste when vials expire without being used (Note: Although there is no patient safety impact, we classify this as an error for simplicity.) | Manual: relies on mental recall of availability of used partial vial or visual scan of cleanroom to see if a used partial vial is present TAWS: automated prompt that used partial vial is available |
| Selection errors | |||
| Incorrect container selected | Use of wrong type of container (syringe vs IV bag vs elastomeric infuser) or use of container of incorrect size or material or with incorrect diluent; for example, IV bags vary in size (eg, 250 mL vs 500 mL), material (eg, PVC vs non-PVC plastic), and diluent (eg, 5% dextrose in water vs 0.9% sodium chloride injection) | Could lead to patient receiving drug in wrong concentration, with incompatible diluent, or for wrong duration | Manual: visual inspection by cleanroom technician or pharmacist when reviewing key steps through webcam (ie, video reviewa) TAWS: barcode scan identifies error; detection prior to product’s use prevents errors and subsequent costs of wasted product |
| Incorrect drug selected | Use of drug vial other than what is prescribed; includes errors in drug concentration or brand | Can cause severe harm or death; can be difficult to detect because most drugs are clear colorless liquids, so injection of incorrect drug is often indistinguishable from injection of correct one | Manual: visual inspection by cleanroom technician or pharmacist when reviewing key steps through webcam (ie, video reviewa) TAWS: barcode scan identifies error; detection prior to product’s use prevents errors and subsequent costs of wasted product. (Note: Different brands of the same drug may not be distinguishable to the TAWS, depending on the institution’s configuration.) |
| Measurement errors | |||
| Incorrect amount of reconstitution diluent withdrawn | Too little or too much diluent drawn up in preparation to inject into powdered drug | May lead to incorrect concentration of drug and compromise dose accuracy for subsequent compounding steps | Manual: technician relies on mental recall or checks an information sheet for amount to use; followed by visual inspection by cleanroom technician or pharmacist when reviewing key steps through webcam (ie, video reviewa) TAWS: step-by-step instruction of type and amount of diluent to use; gravimetric weight scale verifies correct amount |
| Incorrect amount of reconstitution diluent injected | Too little or too much diluent injected into powdered drug | Will compromise dose accuracy for all subsequent compounding steps, and the error may affect multiple patients if same drug vial is used to provide doses for different preparations; if underdiluted, powder may not be dissolved completely | Manual: no check possible (injection amount cannot be verified visually once injected) TAWS: gravimetric weight scale verifies correct amount |
| Incorrect container adjustment amount | Adding or removing wrong amount of diluent in IV bag or elastomeric infuser (no diluent is required for syringe containers) Elastomeric infusors must be filled with the correct amount of diluent, whereas IV bags need to have fluid withdrawn to make room for the volume of drug being injected. |
Can alter concentration of compounded product | Manual: no check possible (adjustment amount cannot be verified visually once adjustment performed) TAWS: gravimetric weight scale verifies correct amount (Note: For elastomeric infusers, a cleanroom technician programs automated pump to inject required amount of fluid into container. The technician does not verify the accuracy of the pump for each preparation, but 2 pharmacy team members calibrate the pump at the start of the day.) |
| Incorrect amount of dose withdrawn | Too little or too much drug is drawn into syringe(s) | Potential patient harm from under- or overdosing | Manual: visual inspection by cleanroom technician or pharmacist when reviewing key steps through webcam (ie, video reviewa) TAWS: gravimetric weight scale verifies correct amount |
| Incorrect amount of dose injected | Too little or too much drug injected into final container | Will result in dose error and can cause patient harm | Manual: no check possible (injection amount cannot be verified visually once injected) TAWS: gravimetric weight scale verifies correct amount |
Abbreviations: IV, intravenous; PVC, polyvinyl chloride; TAWS, technology-assisted workflow system.
aThe real-time video review is triggered by the cleanroom technician verbally calling out “Check please!”, stating the patient’s name, and then showing the drug label to the video camera, which is being viewed remotely by a pharmacist. The pharmacist then reads the label and identifies the corresponding patient’s order in their own order records. This approach minimizes bias by leaving it to the pharmacist to manually reconcile the drug name, dosage, container, and quantities of drug or reconstitution diluent present in the syringe being presented to the video camera.