October 12, 2001 (Ira Pilgrim)

Laboratory

There is nothing permanent except change.

Heraclitus (537-457(?)BC)

I went for a physical the other day and the doctor ordered a CBC(Complete Blood Count). I went to the laboratory's collection station where a woman took down my name, address and Medicare number. She then sat me down, tied a tourniquet around my arm, placed a tube in a holder that had a small needle at the end and inserted the needle into my vein and filled the tube. The tube contained a substance that kept the blood from clotting. The needle was so sharp that I barely felt the stick. From there, the tube would be sent to a large central laboratory where the tests would be performed.

At age 18, I was drafted into the army. After 3 months of medical basic training, I was sent to the 99th General Hospital. They sent me to laboratory technician's school at Walter Reed Hospital in Washington, DC. One of the first things that I was taught was how to sharpen hypodermic needles on a small stone. I was taught to push it through some gauze to detect burs. Yes, needles were re-sharpened, sterilized and used over and over again. I took great pride in the fact that my needles were sharp and had no burs. I got to be very good at getting blood. As a vampire, I would have put Count Dracula to shame. Many many years later, I was bragging about my expertise and someone asked me what my batting average was. I said that I got 4 out of 5. She said "That doesn't seem very good." I replied, "That was after everyone else in the lab had given up." I didn't have time to pity the poor patient who might as well have been a pin cushion.

About the only thing that hasn't changed in drawing blood is the tourniquet, which is a piece of rubber surgical drain tubing. It is the one thing that couldn't be improved upon. With really difficult patients, I would use a blood pressure cuff, but that is too complicated for a routine blood draw.

When that tube of blood gets to the laboratory, it will be gently shaken by a machine. The blood will then be fed to a machine which will count the various kinds of cells, as well as differentiate between the different types of white blood cells. A printout of the results will come out of the machine. Its accuracy is amazing. The time that it takes to do the complete blood count is measured in seconds. It takes more time to record the name of the patient.

What did it take to do a CBC in the good old days? For one thing, it was done by sticking a finger or ear lobe instead of a vein. This was done with a pointed surgeon's scalpel blade. The blood was sucked (by mouth, using a long rubber tube) into a calibrated glass pipette with a bulb in the middle. Then the diluting fluid was sucked up to a second mark. Two of these pipettes were taken; one for white blood cells and the other for red cells. A microscope slide was spread with blood. It would later be stained and the different types of cells would be identified and 100 cells would be counted under the microscope. Then the used pipettes were cleaned by hand. They were much too expensive to just throw away.

I would hold a pipette between my thumb and middle finger and shake it with a special motion. The great advance of the day was an electrical pipette shaker which vibrated the pipettes while I counted another specimen under the microscope. The whole procedure took, I would guess, somewhere between 5 and 15 minutes per patient. Counting blood cells had to be the most boring job ever created. It would numb both the butt and the mind. The modern machines are much faster and much more accurate

The difference between then and now is like the difference between driving a donkey cart and driving a new Mercedes.

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