Generalizability and Effectiveness of Butterfly Phlebotomy in Reducing Hemolysis.

Objective: The objective was to test the hypothesis that exclusive use of butterfly needles for phlebotomy, compared with sample collection via intravenous (IV) catheter, will reduce rates of sample hemolysis.

Methods: This was an observational study of hemolysis rates before and after implementation of a "butterfly-only" phlebotomy protocol. Weekly hemolysis rates, generated by the central laboratory, were collected and the proportion of hemolyzed specimens before and after protocol implementation were compared.

Results: Prior to institution of the butterfly-only protocol, 11.3% of specimens sent from the emergency department were reported as hemolyzed. During the postintervention period, only 4.3% of specimens were hemolyzed for a proportionate decrease of 62% and an absolute decrease of 7.0% (95% confidence interval = 6.6% to 7.3%).

Conclusions: Use of a butterfly-only phlebotomy protocol cuts hemolysis rates by more than half when compared with IV catheter phlebotomy.