Blood, urine, pus, spinal fluid… these bodily fluids play an important role in diagnosis (that is, in the process of determining what ailment a patient is suffering from). The analysis of these fluids takes place in a laboratory, using scientific methods and instruments.

During the 19th century, science began to interact with medicine. By the early 20th century, hospitals were being designed with laboratories right in them—it was like science and medicine were moving in together. Now they are married in such a way that it is hard for us to imagine them apart.

Though the microscope was invented around 1600, it only became widely used for diagnosing disease around 1900. At around that time, the microscope started to be used to look at blood samples and count blood cells, to look at bacterial cultures to identify an infectious disease, or to look at samples of tissues to identify abnormal cells and structures.

Before labs were common in hospitals, doctors sometimes did the work themselves, with basic microscopes (like this one) in their offices.

As laboratory techniques became more sophisticated, not all medical doctors had the Read More
Blood, urine, pus, spinal fluid… these bodily fluids play an important role in diagnosis (that is, in the process of determining what ailment a patient is suffering from). The analysis of these fluids takes place in a laboratory, using scientific methods and instruments.

During the 19th century, science began to interact with medicine. By the early 20th century, hospitals were being designed with laboratories right in them—it was like science and medicine were moving in together. Now they are married in such a way that it is hard for us to imagine them apart.

Though the microscope was invented around 1600, it only became widely used for diagnosing disease around 1900. At around that time, the microscope started to be used to look at blood samples and count blood cells, to look at bacterial cultures to identify an infectious disease, or to look at samples of tissues to identify abnormal cells and structures.

Before labs were common in hospitals, doctors sometimes did the work themselves, with basic microscopes (like this one) in their offices.

As laboratory techniques became more sophisticated, not all medical doctors had the time or the skills to do them themselves. The occupation of hospital lab technician was born. Lab technicians today are specially trained to use expensive equipment for diagnosis. This equipment can include specialized microscopes, electrophoresis machines, and spectroscopes.

What can your pee reveal about your health? For some reason, since about the 1400s people have been examining urine for clues about sickness and health. At first, they looked at basic characteristics like colour, smell, and taste(!). Then, as the science of chemistry developed, more sophisticated analysis was applied to urine to help diagnose disease.

One early conclusion was that people who suffered from diabetes tended to have sweet urine. Knowing this, physicians used the presence of sugars in the urine as a way to determine if a patient had diabetes.

Today the urine test is still a standard procedure—have you had one lately?

How many blood cells are in a sample of blood? Traditionally, blood cells were counted one by one, using a hemacytometer. A diluted blood sample was placed on a slide that had grid lines on it. Using a microscope, the technician counted the number of cells in each square, and then added them up to get the total. This was tedious work. Technicians suffered from eyestrain, not to mention the frustration of losing count and having to start over!

Mechanical counters helped—the technician still had to peer at the sample through the microscope, but could at least keep count by pressing the buttons on the counter.

Today the whole process is automated with a machine called a Coulter Counter.

© CMST & UHN 2002. All Rights Reserved.

3D Object - See the microscope in 3-D

Click and drag on the image to rotate the microscope.

Canada Science and Technology Museum and the University Health Network Artifact Collection
1893
© CMST & UHN 2002. All Rights Reserved.


Microscope

Microscope

Canada Science and Technology Museum and the University Health Network Artifact Collection
1974
© CMST & UHN 2002. All Rights Reserved.


Urine Sugar Test Case

Urine Sugar Test Case

Canada Science and Technology Museum and the University Health Network Artifact Collection

© CMST & UHN 2002. All Rights Reserved.


Hematocytometer

A lab technician at St. Boniface General Hospital examines a blood sample under a microscope.

Canada Science and Technology Museum and the University Health Network Artifact Collection
1986
© CMST & UHN 2002. All Rights Reserved.


Using the centrifuge was an easier way to estimate the number of blood cells in a sample of blood. The sample was placed in a tube in the machine. The machine spun the tube around, forcing all the heavier particles (mainly red blood cells) to move to the bottom of the tube, leaving the liquid plasma at the top. Looking at the tube, the technician saw a layer of red at the lower end, and a layer of yellow above. The size of these layers indicated the proportion of red blood cells in the sample, which could be compared against a standard. The centrifuge is still used in diagnostic laboratories.

The sputum case was a container used to collect a sample of sputum (spit) to test for the presence of disease organisms, like TB. These specimens had to be handled carefully, as these little packets potentially contained the very nugget of contagion. Either the physician conducted the test, or, more frequently, delivered the specimen to an independent laboratory that would conduct the test and report the findings back to the doctor.

Once we figured out that different kinds of bacteria caused different kinds of disease, we looked for ways to detect the presence of these Read More
Using the centrifuge was an easier way to estimate the number of blood cells in a sample of blood. The sample was placed in a tube in the machine. The machine spun the tube around, forcing all the heavier particles (mainly red blood cells) to move to the bottom of the tube, leaving the liquid plasma at the top. Looking at the tube, the technician saw a layer of red at the lower end, and a layer of yellow above. The size of these layers indicated the proportion of red blood cells in the sample, which could be compared against a standard. The centrifuge is still used in diagnostic laboratories.

The sputum case was a container used to collect a sample of sputum (spit) to test for the presence of disease organisms, like TB. These specimens had to be handled carefully, as these little packets potentially contained the very nugget of contagion. Either the physician conducted the test, or, more frequently, delivered the specimen to an independent laboratory that would conduct the test and report the findings back to the doctor.

Once we figured out that different kinds of bacteria caused different kinds of disease, we looked for ways to detect the presence of these bacteria in patients.

One way was to take a specimen from the patient (say, a swab of mucous from the throat) and smear it (using a sterilized inoculating loop) into a container containing food specific to the bacteria in question, say, diphtheria. The container (often a round “petri” dish) was then placed in an incubator at a temperature suited to the reproduction of that particular bacteria species. If the bacteria were present, they grew and reproduced, showing whitish spots visible to the naked eye. Nothing appeared if the bacteria were not present.

When looking for disease in tissues, the microtome comes in handy. It is a sophisticated slicer. Its very sharp blade cuts very thin slices of tissue, to be viewed under a microscope. The tissue specimen is first “fixed” (so that it does not decay), and stained (so that the relevant features show up). Then the specimen is made rigid (either embedded in wax, or frozen)—a crucial step if you want extra-thin slices.

With this microtome the tissue was frozen, and then placed on a stand below the blade. The blade swung around above it, taking its slices off the top.

Your blood can reveal how well your lungs are working. When you breathe, oxygen enters your lungs, where it is absorbed into the blood stream. At the same time, carbon dioxide leaves the blood, goes into the lungs, and leaves the body when you exhale.

Not enough oxygen in the blood, or too much carbon dioxide, can indicate that something is not right with the gas exchange in the lungs. So how can this be measured? A sample of blood can be taken and its content of CO2 and O2 can be analysed in the lab.

© CMST & UHN 2002. All Rights Reserved.

Centrifuge

Lab facilities at the Ninette Sanatorium

Photo courtesy of Western Canada Pictorial Index

© Western Canada Pictorial Index


Johnson Sputum Cups

Johnson Sputum Cups

Canada Science and Technology Museum and the University Health Network Artifact Collection
c. 1950
© CMST & UHN 2002. All Rights Reserved.


Inoculating Loop

Lab technician with bacterial cultures in petri dishes, Toronto General Hospital.

Canada Science and Technology Museum and the University Health Network Artifact Collection

© CMST & UHN 2002. All Rights Reserved.


Microtome

Microtome

Canada Science and Technology Museum and the University Health Network Artifact Collection
c. 1960
© CMST & UHN 2002. All Rights Reserved.


Glucose Meter

When chemistry was applied to diagnosis of diabetes, it was an activity that took place in a hospital lab. Now diabetics living with their disease can check the amount of sugar in their blood by using a glucose (sugar) meter, right at home.

Canada Science and Technology Museum and the University Health Network Artifact Collection
1995
© CMST & UHN 2002. All Rights Reserved.


Hackney-Collier Analyzer

Hackney-Collier analyzer for measuring carbon dioxide in the blood.

Canada Science and Technology Museum and the University Health Network Artifact Collection
1970
© CMST & UHN 2002. All Rights Reserved.


Learning Objectives

The learner will:
  • Observe evolution of hospitals, tools and treatments throughout the twentieth century;
  • Identify the evolution of medical technology and discuss its contribution to treatment and medical care;
  • Illustrate concepts in biology, identify specific diseases and treatments offered (past and present).

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