Autor(s): D. Giavarina, L. Pasquale, G. Mezzena, G. Soffiati
Background. Previous papers showed and increased percentage of haemolysed samples by using intravenous catheters, compared to venipuncture, and vice versa. Nevertheless, intravenous catheters are preferred by emergency departments and intensive care units, since they reduce the number of punctures needed, with an increment of sample rejection for haemolysis. There are no studies on the catheter materials and the possible differences in the haemolysis percentages. Aim of this study is to verify the correlation between the percentage of not suitable samples for haemolysis and different catheters materials, in an emergency hospital department. Methods. We compared the rejection percentages for haemolysis of samples come from the Emergency Department, during a period of 78 consecutive days. 91 specimens were obtained by BD Insyte™ Autoguard ™ (group A), 92 by intravenous catheter B Vasofix ® Safety (group B), 90 by Terumo Surflo-w (group C) and 90 by Neo Delta Ven T (group D). All catheters had a needle of 18 gauge. 100 consecutive samples drawn by a needle 21 gauge directly connected to the holder, coming from the Intensive Care Deparment, were used as control group. Results. Enrolled patients were 463 in all. In group A, 19/83 samples (22.9%) were hemolysed; in group B, 14/77 (18.2%); in group C 17/74 (23%); and in group D, 14/87 (16.1%). In the control group there was a 3% of rejected samples. Conclusions. All the catheters for venipuncture show higher percentages of haemolysis compared to direct venipuncture. Some differences are registered between different materials, without however statistical significance. These data confirm that intravenous catheters are not suitable for a correct venous blood sample collection.
Key-words: blood collection, haemolysis, catheter materials, phlebotomist.