Can an unused indwelling peripheral intravenous (IV) line be used for drawing blood during daily laboratory tests?

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Last updated: May 20, 2025View editorial policy

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From the Guidelines

No, it is not recommended to use an indwelling peripheral IV line for drawing blood during daily labs due to the potential for hemolysis and contamination of the blood sample. According to a recent study published in 2024 1, the use of IV catheters for blood draws has been found to have a higher hemolysis rate, which can affect the quality of the blood sample. Additionally, the lubricant coating and needle material used in IV catheters can potentially contaminate the specimens, affecting antigen-antibody binding in some immunoassays.

When considering the use of an existing IV line for blood draws, several factors come into play, including:

  • The potential for dilution or contamination from IV fluids or medications
  • The risk of inaccurate lab results due to hemolysis or contamination
  • The importance of preserving vein integrity and reducing patient discomfort from multiple needle sticks
  • The need to follow institutional protocols and policies regarding blood draws from peripheral IVs

In light of these considerations, the preferred method for drawing blood is venipuncture using a needle and vacutainer tubes, as recommended by O'Bryant et al. 1. If an IV line is used, it is crucial to flush the line with normal saline before and after drawing blood and to discard the first 1-2 mL of blood to minimize the risk of contamination or dilution. However, given the potential risks and limitations, it is generally recommended to use a new straight needle venipuncture instead of an existing IV line for drawing blood.

From the Research

Using Indwelling Peripheral IV Lines for Drawing Blood

  • The study 2 found that blood samples extracted from a peripheral catheter with or without drug infusions are valid for the analysis of hematology, biochemistry, and coagulation parameters.
  • However, the same study noted that peripheral catheters are not suitable for venous blood gases analysis, as differences exceeding 2 SDs were found in parameters such as pH, partial pressure of carbon dioxide, and partial pressure of oxygen.
  • The use of an existing peripheral catheter for drawing blood samples can be beneficial, as it reduces patient discomfort and the risk of complications related to venipunctures 2.
  • There is no direct evidence in the provided studies that addresses the specific scenario of having two indwelling peripheral IV lines not in use, but the general principles of using peripheral catheters for blood sampling can be applied.

Best Practices for Intravenous Line Management

  • A review of best practices for intravenous line management 3 focused on concepts of site selection, skin preparation and insertion, securement, and maintenance and removal criteria for peripheral and central intravenous lines.
  • However, this review did not specifically address the use of indwelling peripheral IV lines for drawing blood samples.
  • Another study 4 discussed evidence-based practice for drawing blood samples from vascular access devices, but it did not provide specific guidance on the use of peripheral IV lines.

Central Line Care and Management

  • Studies 5 and 6 focused on central line care and management, which may not be directly relevant to the use of peripheral IV lines for drawing blood samples.
  • However, these studies emphasized the importance of proper maintenance and care of vascular access devices to prevent complications such as infections and thromboses.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Drawing blood samples from vascular access devices: evidence-based practice.

Journal of infusion nursing : the official publication of the Infusion Nurses Society, 2003

Research

Central Line Care and Management: Adopting Evidence-Based Nursing Interventions.

Journal of perianesthesia nursing : official journal of the American Society of PeriAnesthesia Nurses, 2021

Research

[Central venous access for cancer chemotherapy].

Presse medicale (Paris, France : 1983), 2018

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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