Medical Laboratory Monologues (Part I) "Chemistry"

Here begins the series of “Day in the Life of a Medical Laboratory Scientist” posts.

(Warning: get comfy! Although I am leaving a lot out, this is a pretty long post!)

Introduction: For those of you unaware, the medical laboratory is divided into four main areas: chemistry, hematology (blood studies), microbiology (bacteria and parasite studies), and the blood bank. These areas are defined both by the scientific focus and methods used for testing. Chemistry tests are performed on blood, urine, cerebrospinal fluid, and other body fluids. These tests all use chemical reactions in vitro (in a tube—these reactions do not normally occur within the body) to determine levels of various substances in the body. Hematology is the study of blood. Testing in this area is all about the cellular makeup of the blood, and the presence of blood in other fluids. Microbiology is a broad term meaning “the study of microorganisms,” which (in the lab) almost always means bacteria. It is not an area for the faint of heart or queasy of stomach! Finally, blood banking is a vital area in every hospital. It is the highly regulated preparation, storage, and testing of donor blood that is available to be transfused to patients in the hospital. This area is also not for the faint of heart! Blood banking can be stressful because every transfusion is a life-or-death situation.

Author’s Note: In this first post of the series, I will be mentioning many small details such as the use of a security badge, labcoat, gloves, etc. These small details apply to the entire laboratory experience and will therefore be left out of subsequent posts unless there are details specific to the area in question. 

Day 1: Chemistry

At Salem Health, the only time I am working solely in chemistry is at the Regional Lab where the low-priority testing (anything that is not needed immediately, e.g. a strep throat culture) is performed. I would know the area and location (Hospital vs. Regional) where I am working on a particular day by looking at a complex, color-coded schedule. Each hospital has its own system for scheduling—it is never easy. But ours has a different color for each location, and a letter code for each area. It took me months to understand how to read it! Once I know where to go, I hop in the car and head to the Regional Lab where my shift starts at 0645 (yep, we use the 24 hour clock in the lab).

I have to swipe my badge to get into the lab (very official), because it is a secure area! We work with a lot of biohazard materials, and PHI (personal/protected health information) is used throughout the lab during testing. You have to be specially trained to be a janitor or even the person who changes light bulbs in the lab! We have a break room where all personal items are stored in a locker, and there are refrigerators (labeled “No Blood or Biological Specimens”) where you can keep your lunch. No phones, food, drink, etc. in the lab! Once my things are put away in the locker, I head into the lab and get my labcoat from a rack hanging near the door. We can wear the same labcoat for a few weeks, or until it gets dirty—usually not anything gross, just grub from wearing it every day for two weeks! What a scientist keeps in the pockets of his/her labcoat is personal treasure. We all hoard pens and nice sharpies because we are constantly labeling, writing notes, and it always seems like there is a shortage. Every time I get a new labcoat, I carefully move the contents of my pockets into the new labcoat and put it on my labeled hanger.

What do I have in my pocket?

Right now, in my upper pocket I have three sharpies (two regular—red and blue, and a fine tipped red one), a highlighter, a carefully selected ball-point pen, and a special permanent marker for labeling glass slides (regular sharpie will be washed away by the staining process). In my lower pockets I have a slide case, a razorblade, a pad of sticky notes, alcohol pads, and a handful of clean nitrile gloves. Everyone’s pockets are different, but these are the treasures I feel like I need at all times!

Once I am wearing my labcoat, I put on gloves. Everyone in the lab knows their own hand size (I am a medium), and perhaps the hand size of a few other people in the lab. Sometimes I forget how odd it would seem to people of other professions to wear gloves during an entire eight hour shift. I have learned to do many things with gloves on! Now that I am all decked out in my usual PPE (personal protective equipment), it is time to get to work!

The chemistry area is highly automated. In school we had to learn and perform every test manually, but now we have machines that allow us to do a high volume of tests each day. This works especially well in the chemistry department because chemistry is such an exact science. Everything is measured precisely, and added in a specific order. This is something we can program machines to do because it is the same every time, on every patient. My main job in the chemistry area is to perform machine maintenance on the Cobas analyzers, and review the results given to me by the machines. Although I no longer have to measure and pipette all of the reagents and samples for the chemistry tests (other departments are much less automatic), I do still have to make up some reagents—which feels very science-y! We really do use the flasks and beakers to measure the components of the reagents.

In the morning, the main goal is to get the analyzers ready for a day of testing. At the hospital location, our analyzers are running 24/7, so we have to do maintenance with as little down time as possible—always keeping one machine functional while the other is down. At regional, however, the machines are shut down during the night, so we have to bring up both at once. Daily maintenance is done on each machine, and involves cleaning, calibrating, and running controls (see my last post). This process can take between one and two hours, depending on the day. This part is not an exact science, and the machines do not always behave as they should!

The Mighty Cobas 6000 (from google images)

Once the machine is “in control” as defined by our two-standard-deviation parameters, we are ready for testing! The specimen management team works from the wee hours of the morning to collect and prepare specimens to be ready to test the instant the scientist (also referred to as a “tech”) is ready. The specimen management team receives the orders from the couriers or the phlebotomists and prepares each sample to be put onto a machine, slide, test card, kit, innoculum, or media. This often involves making aliquots, centrifuging, relabeling, streaking agar, and making gram stain slides. In chemistry we mainly process aliquotted and centrifuged tubes. Once the machines are up, the specimen management workers begin loading samples onto the MPA (Salem Hospital’s particular name for our automated line that carries samples to the machines). I honestly have no idea what it stands for.

Loading racks for the MPA

Tubes loaded onto the MPA are scanned (each has a barcode with patient information and the tests needed) and poured off. The MPA’s big brain runs an algorithm that tells it the most efficient way to test all of the samples—putting stat samples above those that are routine and grouping samples together that have similar tests ordered. Not everything can be loaded and run automatically. Some samples need extra attention and have to be prepared and loaded manually. Specimen management brings those samples to me and puts them into a rack—sorted into routine and stat. I read the orders on these tubes, put them in an appropriate rack, check specimen quality, and load them onto the machine to be tested. Some samples are not acceptable, and need to be recollected due to hemolysis (bursting of the red blood cells due to phlebotomy technique), clotting (most blood used for testing is drawn into tubes coated with anticoagulant, so the components are not changed by the clotting process), or insufficient quantity. Each of these rejected specimens requires a form signed by a MLS, and is returned to specimen management. They will inform the nurse or phlebotomist of the need for a new tube.

While all of this is going on, it is my main job to look at the computer system and review the results coming off the machine. The machine talks to our big brain and sends across the results for each patient. If the results are within the normal range (essentially “negative”) for that particular patient, the computer automatically accepts the result and downloads it to the patent’s chart for the physician to access. If any of the results are abnormal, the computer will not accept them, and they will hold up in the system, awaiting review. I need to review these results (e.g. “Serum total protein 7.0 g/dL”) and decide if they are accurate. This requires knowledge of the body systems, disease states, and medical possibilities. It is a fine line between an abnormal result due to machine malfunction, and an abnormal result due to a patient’s disease state. It is sometimes necessary to refer to procedures, manuals, patient history, and the opinion of another tech in the case of an unusual combination of results.

After the machine is through running each sample, it spits out the racks for me to unload. I toss the aliquot tubes (we can get rid of them because they are not the original patient sample), and recap the original patient tubes to be stored. If I neglect my machine for too long, the out-tray will fill up and the Cobas will give me an alarm. The Cobas analyzers are always alarming. They are very needy machines and often need something loaded, unloaded, reloaded, fixed, tweaked, ordered, re-ordered, repositioned, or re-calibrated. Although chemistry is automated, it is still a lot of work!

Finally: a brief mention of paperwork. Every miniscule detail of the lab is regulated by various organizations: the FDA, CLIA, CAP, and the hospital itself. Each of these organizations requires detailed documentation of everything that happens in the lab (now you see why having your favorite pen handy is important!). It is also required to document anything out of the ordinary during your shift, and to alert the employees on the next shift to anything that they need to pay attention to. It is very important for testing to be free from errors so that our results can be trusted by the physician. If the lab is sloppy and turning out inaccurate results, it would be bad news!! At each shift change, we have a huddle or pass-off meeting. If you are in the middle of a test, or waiting for a particular result, it is not only courteous but necessary to inform the next tech. If I was in the middle of testing a specimen that needed special attention (like a dilution or airfuge) and neglected to tell the next shift, the sample could get forgotten, sent out with an inaccurate result, or delayed while the tech investigated the course of action to be taken. Each of those situations causes a delay in patient care which is bad for the patient and bad for us!

Phew!! Congratulations on reaching the end of this post! After a long day of running back and forth to load, unload, and take care of the machines, analyze results, and fill out paperwork, it feels great to hang up my labcoat, retrieve my belongings from the break room and head home.

Thanks for sticking with me! If you have any questions, feel free to post below! I love talking about my job, so fire away. (If you can’t figure out how to post a comment, you can text or email me as well!)

Stay tuned for “Day 2: Hematology” coming soon to the adventure blog!

Onward and Upward



**Please note that all photos are from google images, and not photos of the lab where I work! They are just for fun.**