Factors affecting hemolysis rates in blood samples drawn from newly placed IV sites in the emergency department

To decrease the number of hemolyzed samples in the emergency department, performance improvement activities were implemented, including phlebotomy classes for staff, evaluation of blood draw equipment, and a study to evaluate factors attributed to hemolysis of blood samples when drawn at the time a new intravenous catheter is inserted.

In a study with an observational design conducted in June and July 2004, researchers examined the cases of 100 randomly chosen patients who had blood drawn through newly placed peripheral intravenous access.

In this study, the blood draw collection factors with the highest hemolysis rates included blood samples drawn between 12:00 am to 5:59 am; samples drawn by patient care technicians; right-hand site; 22-gauge intravenous catheters; syringe draws; blue tubes; 6.0 mL tubes; difficulty drawing blood; 2 tries for intravenous placement; resistance when aspirating blood using a syringe; and respiratory discharge diagnoses. Statistically significant (P < .05) blood draw factors included intravenous placement sites of right hand/forearm and antecubital; intravenous catheter size 22 gauge; blood drawing categorized as difficult; number of tries for intravenous placement; blood tube size 1.8 mL; and discharge diagnoses of respiratory, gastrointestinal, reproductive, dermatologic, and endocrine.

Clinically meaningful factors associated with hemolysis rates included the use of a 22-gauge intravenous catheter size, which resulted in a hemolysis rate of 60%; in addition, intravenous placement sites on the right side had statistically significant higher hemolysis rates than the left side, a finding that merits further research. As a result of the study we modified our standard operating procedure to discontinue the use of a 22-gauge or smaller intravenous catheter in adults. If required for small vein sticks, the use of a straight needle stick to obtain blood samples should be considered. The results of this study underscore the importance of education and training and the consideration for regular competency testing for staff with phlebotomy responsibilities.