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Determining optimal waste volume from an intravenous catheter
Rachel B Baker1, Suzanne S Summer, Michelle Lawrence
1Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. rachel.baker@cchmc.org
Summary
Minimizing blood waste from intravenous (IV) catheters is crucial. This study found that 1 mL of waste is sufficient to obtain an undiluted blood sample, preventing unnecessary blood draw.
Area of Science:
- Clinical Laboratory Science
- Medical Device Technology
Background:
- Blood sample collection via intravenous (IV) catheters requires discarding an initial volume, termed 'waste', to eliminate contaminants like saline or heparin.
- Determining the optimal waste volume is essential to prevent unnecessary blood loss and ensure sample integrity.
Purpose of the Study:
- To ascertain the minimum waste volume required from an IV catheter to obtain an undiluted blood sample.
- To establish evidence-based guidelines for IV blood draw waste volume.
Main Methods:
- A repeated-measures design was employed with 60 healthy adult participants.
- An IV catheter was inserted, and blood samples were collected at baseline and after discarding incremental waste volumes (0.5 mL to 3 mL).
- A random effects mixed model analysis was utilized to identify the point at which the sample became undiluted.
Main Results:
- The study identified 1 mL as the minimum waste volume necessary to achieve an undiluted blood sample.
- This finding indicates a stabilizing point for sample purity after discarding 1 mL of initial draw.
Conclusions:
- A waste volume of 1 mL is sufficient when drawing blood from an IV catheter to ensure sample accuracy.
- Implementing this 1 mL waste guideline can reduce unnecessary blood discard in clinical practice.
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