56 year old female was brought to the emergency room with complaints of dyspnea. Her breathing became more and more laboured so they chose to intubate and admit to ICU. In 2017, she had a bone marrow biopsy that confirmed Philadelphia chromosome positive and CML. However, the patient declined treatment. Her current condition is due to blastic crisis. Every time a CBC is ordered, we automatically do a dilution and manual hematocrit.
I am also a biochemistry tech so I would like to share the chemistry side of her case. The first chemistries ran on this patient was an arterial blood gas. As you can imagine, her results were in the critical values. Next was a chemistry panel that came back mostly unremarkable other than her potassium result which was in the tens (ie. 14.6 mmol/L), not compatible with life. A comparison with her rapid potassium result (from the blood gas) showed her potassium levels to be normal. Contamination was ruled out. After some research, it was found that her blast crisis was also causing her to be pseudohyperkalemic. How? The high fragility of her blood cells, coupled with the specimen being sent to the lab via pneumatic tube, and the centrifugation of the PST tube, caused copious amounts of potassium to be released from the damaged cells. Our solution to this problem was to have her samples hand delivered to the lab, her PST tube run on our blood gas analyzer (pre spun) to obtain a rapid K result for reference, and then centrifuged and run normally on the main analyzer. It was found that the hand delivering/gentle handling of these samples preserved the integrity of her blood cells, thus allowing us to report more accurate potassium result.