During the preanalytical phase of blood gas analysis, hemolysis in blood samples can occur if you mix too vigorously. 
An example of a hemolyzed blood sample:
Vigorous mixing leads to hemolysis in blood gas samples. In a hemolyzed sample erythrocytes rupture and components from inside the cell(s) are released into the plasma. One of these components is potassium (K⁺). 
Outcome of hemolysis in blood samples
Hemolysis in blood gas samples leads to erroneous increased potassium values and to other inaccurate values, such as a decrease of pH, pCO₂ and pO₂. 
Reduce the risk of hemolysis in blood gas samples
The suggested technique for mixing involves a repeated and gentle inversion of the syringe while rolling it between your palms. 
However, you can also use the automatic mixing feature in your blood gas analyzer to obtain a homogenous sample while minimizing the risk of hemolysis from occurring. 
Minimize hemolysis in blood samples with automatic mixing
You need to mix a sample sufficiently in order to obtain a homogeneous sample to get accurate results. However, the technique of manual mixing is applied inconsistently. 
Your solution to reducing hemolysis in blood samples lies in automatic mixing.
At Radiometer, we designed the safePICO blood gas syringe to help you adequately mix your sample. The syringe is designed to help reduce the risk of hemolysis in blood samples.
Prior to analysis, sufficient mixing is crucial to obtain a homogeneous sample. The safePICO syringe and automatic mixing on a blood gas analyzer helps you produce a homogeneous sample, while reducing the risk of hemolysis from occurring. 
The safePICO syringe helps you reduce the risk of other preanalytical errors. In addition to hemolysis, examples of such errors are clots or an air bubble in the sample, needlestick injuries or patient-sample mix-up.