Introduction

1. Comparison of aPTT values from venipuncture and central venous access device specimens in hospitalized adult patients receiving continuous heparin infusions Mary Sue Dailey, APN- CNS, Fortunata Dabu, RN, BSN, Sue Durkin, APN- CNS, Barbara Gulczynski, APN- CNS, NP, Colleen O’Leary, APN-CNS, Carrie Bauman, RN, BSN, Karen Calimlim, RN, BSN, Karen Hagemaster, RN, BSN, Joy Kennedy, RN, BSN, Barbara Kohn, MTRN, BSN, • Introduction • Continuous heparin infusions require monitoring of aPTT values and appropriate adjustments in the infusion rate. • If the heparin is infusing through the central venous access devices (CVAD), how should aPTTs • be collected? • Peripheral required/desired? • From CVAD acceptable? • Turn off infusion? • Flush first? • Waste amount? • Desired port? • For patients with central venous access devices (CVAD), blood samples may be collected from the CVAD or from a peripheral vein. Discrepancies • Manufacturer’s Guidelines • Arrow (TLC) • Use proximal port • Turn off distal infusions for at least one minute • Discard volume varies from priming volume (dead space) • to 3-10mL • Bard (PICC) • Flush per hospital protocol • Waste 2-6 X the priming volume • 5mL = 6x the priming volume of all non-tunneled PICC • Preliminary Results • Paired blood specimen results compared • 62% of specimens correlate within 10% • Further data analysis concerning type of line, concurrent infusions, and other clinical variables will be performed Study Design Range of % Difference of Lab Draw aPTT and RN aPTT • Paired blood samples from 80 patients receiving a • continuous heparin infusion through a CVAD will be • collected by a research RN and a lab phlebotomist • CVAD specimen • Peripheral Venous specimen • Need 74 subjects (37 in each group) to detect a 2 second • difference between specimens (SD 3 seconds) • Power of .80 and alpha=.05 • Clinical environment and demographic data collected . • Policies • Lab • Turn off infusion • Waste depends on dead spaces : 5-12mL • Coags first • Nursing • Does not mention stopping infusion first • No mention of “desired port” • Waste first 6 mL • No guidelines regarding order of tube fill Further Data Analysis • Comparison of paired blood specimen results, screening for outliers, and unexpected variations • Further review of Clinical Environment and Demographic data to be done, including analysis of trends per individual research RN • Following data verification, descriptive statistics • will be generated • Purpose of Study • Is there a clinically significant difference between • the aPTT results from a specimen collected from • CVAD and a specimen collected from a peripheral • vein? Obstacles and Solutions Professional Standards • Previous Studies • Venipuncturevs Peripheral VAD • Powers (1999) n=32 • Prue-Owens (2006) n=23 • VenipuncturevsArterial Line • Alzetani (2004) n=49 • Heap (1997) n=79 • Venipuncturevs CVAD • Bellmunt. P, et al. (2000) n=74 • Humphries and Baldwin (2009) n=30 • Infusion Nursing Society (2006) • Stop infusion • Flush with 3-5 mL • Distal lumen preferred • Discard volume equal to 1.5-2 times the fill • volume of the CVAD • Patient Consent- Many critically ill • Patient/ Family reluctant/unwilling to be “stuck” • Concurrent focus on central line necessity • Reports generated early AM- patient condition changes • Research RN coverage Selected References • Bellmunt. P., et al. (2000). Sample extraction through central venous catheters to control partial thromboplastin time in patients undergoing heparin sodium perfusion. Enfermeria Intensiva 11(4), 155-60. • Humphries, L., & Baldwin, K. (2009). A study comparing test results from PICCs and veinipunctures. Poster presentation at National Association of Clinical Nurse Specialists Annual Conference. • Actual RN practice • 134 respondents completed online survey • 82% flush prior to obtaining sample • 50% waste 10 mL • 56% collected coag specimen first • 94% stop infusion ATTENTION PHLEBOTOMIST: PLEASE SEE RN BEFORE ____BLOOD DRAW THANKS FROM THE RESEARCH TEAM