OBTAINING BLOOD SAMPLES FROM PERIPHERAL INTRAVENOUS CATHETERS: BEST PRACTICE?

Methods MEDLINE and CINAHL were the search engines used. Key search words were phlebotomy, intravenous catheters, Vacutainers (Becton, Dickinson, and Company, Franklin Lakes, New Jersey), and hemolysis. Both research evidence and manufacturers' evidence were included. Results Eight studies were retrieved (Table 1). Designs included observational, descriptive, comparative, and experimental. In half of the studies,2,6-8 hemolysis was compared between specimens collected from intravenous catheters and specimens collected from venipunctures; in 1 study,5 hemolysis was compared between 5- and 10-mL tubes; and in 3 studies,1,3,4 causes of hemolysis of specimens obtained from intravenous catheters were investigated. In most of the studies, hemolysis was assessed via visual inspection to detect a color change indicating presence of hemoglobin; in a few studies, researchers used spectrophotometers or daily comment logs. Rates of Hemolysis Hemolysis varied considerably between methods and units. Hemolysis occurred in 3.3% to 77% of blood samples obtained via intravenous catheters, whereas it occurred in only 0% to 3.8% of blood samples obtained via venipuncture. Hemolysis of samples obtained from intravenous catheters via different methods ranged from 5.6% to 77% for samples obtained with a Vacutainer, 3.3% to 49% for samples obtained with a syringe, 12.8% to 49% for samples obtained from new intravenous catheters, and 24% for samples obtained from established. © 2009 American Association of Critical-Care Nurses.