Accurate coagulation studies from heparinized radial artery catheters.
We studied the feasibility of obtaining accurate coagulation studies from indwelling, heparinized radial artery catheters in 28 patients after cardiac surgery. PTT assay was chosen because of its frequent clinical use. Thrombin time assay was chosen because it is a component of the coagulation screening panel and because it is useful in assessing heparin contamination of specimens. We conclude that PTT results are reliable when the dwell volume (0.6 ml for the catheter and extension tubing in our study) and an additional 4.5 ml have been discarded (5.1 ml total discard volume). We recommend the collection of samples for thrombin time assay from a separate venous site because results on samples from heparinized arterial catheters are unpredictable.
Gregersen
R A
RA
Department of Physiological Nursing, University of Washington, Seattle 98195.
Underhill
S L
SL
Detter
J C
JC
Schmer
G
G
Lax
K
K
D000328:Adult; D001780:Blood Coagulation Tests / Q000592:standards*; D001916:Brachial Artery; D006348:Cardiac Surgical Procedures; D002408:Catheters, Indwelling; D003422:Critical Care; D006493:Heparin; D006801:Humans; D010314:Partial Thromboplastin Time; D013048:Specimen Handling / Q000379:methods; D013918:Thrombin Time
D006493:Heparin