WHAT DOES THE DOCTOR THINK THIS MONTH?
Ian looks back on his student days and compared medical testing then and now
Have you ever boiled your urine?
I am sure that many of you will have taken a sample of urine to the doctor or nurse at your surgery and will have watched while they tested it. You will have seen them whip off the screwcaps and quickly dip a reagent strip into the urine before watching while the colours on the stick change, indicating the presence or absence of blood, glucose, protein, bile, nitrites and so on. The doctor or nurse will chat to you while this is going on and will share the results with you as the colours change. Each of these sticks costs about 75p so we don't use them unwisely. Altogether, the process takes 90 seconds, the length of time for all the colours on the stick to change.
As many of you will know, one of my roles in life is to examine the medical students at the Norfolk and Norwich University Hospital. A couple of weeks ago, part of my role was to assess how the students dealt with testing a sample of urine and how they washed their hands afterwards. The students would walk in and look at sample bottle as if it was toxic or about to explode. In fact, it was tap water with a drop of yellow dye and a fingerprick of blood in it. The student would then tell me that, usually, they would wash their hands before putting on their rubber gloves; on this occasion, they had been told not to. However, most of them used the spirit hand sanitiser and then struggled to put rubber gloves on to their sticky hands. Having done that, they cast around for a tablecloth, found the paper handtowel dispenser, took two towels, carefully opened them out and laid them on the counter as if they were about to take afternoon tea. Next, they would ask me where the plastic aprons were kept! I soon tired of this and just told them not to make a mess.
Some had been taught to leave the stick in the urine for 15 seconds (incorrect - you dip it in and take it straight out) and, not content with leaving the stick in the urine, they kept stirring it around with the reagent strip for all of the 15 seconds. We than had a technical discussion about the findings which, all too often, revealed several basic misunderstandings on the part of the student, before they had to dispose of the gloves and reagent strip in the appropriate fashion before washing their hands.
Now, handwashing these days is a complicated, six part process - if you want the details, put six steps to effective handwashing into your search engine and the University of Leicester programme will appear. Some of the students had been practising so much that their hands were raw!
All this reminded me of my student days. In the early 1960's, when I was a medical student at the London Hospital we all wore long white coats and looked really important. However, our tasks were rather menial. One of those tasks was to test the urine samples every morning and, in those days, we had no reagent strips to dip into the urine - we had to boil it! Each ward had its own urine testing cupboard, a room 6ft by 4ft with shelves full of reagents, a Bunsen burner, test tubes etc., and just enough room for the medical student and, if he could find one, a compliant nurse (who was "helping") to stand.
The test for protein in the urine involved heating it almost to boiling point in a test tube at 45 degrees above a Bunsen burner. If a white flocculent precipitate was thrown down, it was either phosphates or protein. We then added a few drops of nitric acid - if the precipitate disappeared, it was due to phosphates; if it remained, it was due to protein. When joining the ward, we were told that the first test for Glucose was to dip your finger in and taste it. We all started off doing this until we discovered that we had been "misled" and that the real test for Glucose was as follows: If there is protein present (see above) the urine must be removed by coagulation and filtration before testing for Glucose. Put an inch of the deep blue copper solution in the test tube and heat it until it boils. Add 2 drops of urine and, if no change occurs, keep adding urine until its volume equals that of the original solution. Bring the mixture to the boil and let it cool. If Glucose is present, a yellow deposit will be thrown down as the mixture cools. There were other chemical tests for urea, uric acid, blood, etc., all very time consuming. A lot depended upon how much "help" the nurse provided. Actually, on reflection, it was all quite innocent!
The problem of heating liquids to boiling in a test tube is that they have a propensity to suddenly fly out of the top of the tube, so we had to be very careful to point the end away from the compliant nurse! Of course, when leaving the ward and instructing the following student, it was essential to instruct him in the finger test for Glucose!
The Garden: You will remember that, last year, a splendid cock pheasant moved into the garden in January. By the end of March, he had seven hen pheasants with him and was thoroughly hen-pecked (metaphorically, I hope) by his seven wives and he looked thoroughly dejected and miserable before they all disappeared at the beginning of April.
He reappeared in January this year, initially on his own. He is now accompanied by another cock pheasant, who onl y has one eye, and they seem to be getting on really well together. I can't help wondering .......
Best wishes to you all
Ian G. Nisbet