The Effect of Different Blood Drawing Methods on Hemolysis and Test Results from Intravenous Catheters Used in Emergency Departments.

BACKGROUND

Hemolysis is frequently reported in samples sent from emergency departments. In our study we aimed to compare the influence of invitro hemolysis on test results and hemolysis ratios of different blood drawing techniques (aspiration method and vacuum filling technique) used to draw blood from intravenous (IV) catheters in Emergency Department. Two techniques (aspiration vs. vacuum filling) used to draw blood into three different tubes (Sarstedt S-Monovette® 4.9 mL Serum Gel tube, BD 5 mL Vacutainer® Rapid Serum Tube (RST), and 5 mL Vacutainer® SST™II tube) and evaluated the effect of the hemolysis index of the sera on the tests analyzed.

METHODS

In the emergency department blood was drawn from 128 consecutive patients into Sarstedt S-Monovette® 4.9 mL Serum Gel tubes using aspiration technique and also into BD 5 mL Vacutainer® Rapid Serum Tubes (RST) and 5 mL Vacutainer® SST™II tubes using vacuum filling technique. All the tests requested from the patients were analyzed on all tubes and the hemolysis index of all the tubes were also evaluated.

RESULTS

As a result, the percentage of hemolysis encountered in S-Monovette® vs. SST and S-Monovette® vs. RST was 4.41% vs. 14.71% and 0% vs. 18.97%, respectively (p < 0.001, p < 0.001). In addition to this, the mean values of the test results for each assay in S-Monovette® tubes showed a significant difference when compared to RST and SST (p < 0.01). CKMB and LDH test results found in the tubes filled using the aspiration techniques (S-Monovette®) were statistically significantly lower than the results gathered from the tubes filled using vacuum filling technique (Vacutainer® RST and Vacutainer® SST) (p < 0.001).

CONCLUSIONS

The test results and HI taken from the aspiration method seemed to be more reliable despite the presence of hemolysis.