1. Frey, Anne Marie RN, BSN, CRNI


Venous catheters are placed for the purpose of infusion, and, in the case of central vascular devices, for drawing blood specimens for laboratory analysis. Little scientific research exists on optimal methods to obtain blood samples from catheters, and clinicians use a variety of non-proven techniques. This article includes an overview of multiple techniques, review of research studies and publications, and recommendations for current practice.


"Evidence-based nursing practice" is a catchphrase used today to refer to high-quality healthcare. Evidence-based nursing practice de-emphasizes unsystematic clinical experience as grounds for clinical decision-making, and stresses the examination of evidence from clinical research. Evidence-based nursing practice requires a search for and critique of the best evidence from literature to answer challenging clinical questions so that the highest quality, up-to-date care can be provided to patients. This article provides an overview of the literature regarding the practice of drawing blood samples from vascular access devices (VADs). Recommendations for practice, based on these publications, will be provided at the end of this article. Literature review is among the initial steps in evidence-based nursing practice.


Vascular access devices are placed for therapeutic, research, and diagnostic purposes. 1 The presence of a VAD also may facilitate frequent blood sampling. 2 Little scientific research exists on the optimal method(s) for obtaining blood samples from catheters. Clinicians use a variety of non-proven techniques. Many inconsistencies exist in clinical practice regarding the most appropriate method for obtaining blood specimens from VADs. 3 Concerns related to obtaining lab specimens from VADs include risk of clotting the catheter; risk of blood exposure to the healthcare provider; risk of volume depletion, particularly in neonates, pediatric patients, and the elderly; and risk of catheter-related infection.