Monday, April 30, 2012

Book sale loot

I'm a sucker for a used book sale. Something about picking through tables and tables of books to find old favorites and new possibilities makes me giddy, not to mention the smell of hundreds of books, which is so comforting.

Every year since I moved to Maryland, I've been making an event of the Stone Ridge Used Book Sale, in Bethesda. My aunt lives near the Stone Ridge school, and she's the one who first introduced me to their annual fundraising book sale. The school collects used books throughout the year, and an army of volunteers work at sorting, categorizing, and pricing them before the sale weekend rolls around again in April and they need to line them up neatly on tables in the three gymnasiums. How big is the sale? You're handed a map when you enter the front door. There's a history section and an American history section, each one occupying its own large table. There's psychology, medicine, science, humor, fiction and biography. How-tos, cookbooks, classics and foreign languages in every format: hardcover, paperback, trade paperback, audiobook... 

The sale runs for four days.

We make an outing of it, marking the date on our calendars months in advance so we don't miss it. It seemed to be a little on the sparser side this year, which means that only three gyms worth of tables were filled with books. In previous years, there were boxes of books under the tables, waiting to be brought up by volunteers filling the empty table spaces as books were nabbed. Still, I left after giving the school $48 in exchange for two canvas shopping bags full of books. Want to see what I got?

So many books!

Let's see... a handful of board books for when my nephew comes to visit, a deck of cards with Weber grill recipes on them, and a two-for-one H.G. Wells with The Time Machine and The Invisible Man, both of which I've read but neither of which I owned.

A couple of these are novels I previously read and enjoyed enough to want a copy handy for re-reading: Bridget Jones's Diary (Helen Fielding) and The Art of Racing in the Rain (Garth Stein). I highly recommend the latter - it's written from the point of view of a dog, and it's excellent.

I picked up Blood: An Epic History of Medicine and Commerce (Douglas Starr). Given my profession and current employer, I couldn't leave a book like that on the table. I also got One Hundred Days, My Unexpected Journey From Doctor to Patient (David Biro), because I love reading about medicine and illness from people on the inside.

I'm very excited about To Seek Out New Life - The Biology of Star Trek (Athena Andreadis), which explores the weird life-forms and environments of Star Trek from the perspective of today's biological knowledge. How possible is a methane life-form, anyway? Why am I not getting my drugs by hypospray yet?

I've got Driving Mr Albert (Michael Paterniti), about a road trip taken to transport Einstein's brain across the country, and Uncle Tungsten, a memoir by Oliver Sacks, the neurologist. I also bought Legacy, A Step-by-step Guide to Writing Personal History (Linda Spence), in hopes that it will help me to become a better writer.

I finally put A Complicated Kindness, an award-winning novel by Canadian author Miriam Toews, into my canvas bag after stopping to re-read the back a half dozen times. Obviously, I want to read it. And last, my husband found me If I Die Before I Wake, the Flu Epidemic diary of Fiona Macgregor, by Jean Little. It's got "Dear Canada" written in a banner across the top, and a little research tells me that it's fiction, one of a series of fictional "historical diaries" written around the time of big events in Canadian history, but I still think it will be interesting to read.

Once I'm finished all these, I will box up any that I don't need to keep, and bring them back to Stone Ridge so that someone else can pick them up next year and enjoy them. Unless a friend wants to read them first, of course!

Sunday, April 29, 2012

Taking back the yard

Our backyard has a slight overgrowth problem. Much progress was made last summer on one side of the yard, removing vines and replacing broken sections of fence, but with the subsequent discovery of my husband's terrible reaction to poison ivy, we had to back off from that sort of work.

Years of neglect by the previous owners resulted in a curtain of ivy over two feet thick covering the fence. We weren't even sure what shape the fence was in underneath, because we could barely get to it. The neighbor on that side is content to let that side of his yard resemble a rainforest, so it's not likely that we can ever stop the vines completely, but I wanted our yard back. I'd prefer to look at grass and a fence, and I'd like to give wasps fewer places to hang out.

But ivy is very hard to kill. My husband tried slashing the vines along the whole length of the fence and then spraying the leaves with a herbicide that had "ivy" listed as a usual victim, but the leaves barely even faded. We considered hiring a landscaping crew - we keep getting bright advertising flyers stuffed into our mailbox, so there's no lack of companies to choose from - but those guys are expensive. So, we decided to be reckless and put a "help wanted" ad on Craigslist. Within a few hours, we'd gotten several replies, most of them intelligible. We called back one guy who said he'd bring his girlfriend to help, we set up a time, and then hoped they'd show up and do a decent job.

Here's what the fence looked like once they were finished their 4 hour day. The line where the grass stops is where the ivy ended!

They filled twenty-one huge trash bags with ivy, twigs, and weeds. And the best part? They came back for more. They've done two days now and the yard is almost unrecognizable! There's still more to be done, and they seem willing to finish the job completely, at a price well below what we'd be paying landscapers (which is also cheaper than the medical treatment my husband would need if he hit poison ivy again).

As with all projects we undertake here, it's led to a new project: it seems that the ivy was a supporting frame for the fence. Some sections, not shown in my photo, have fallen completely, and the ones that are still upright aren't very solid. Most of the fencing on that side of the house will need to be replaced, and with the neighbor's short chain-link fence about a foot behind ours, spanning a small section of Maryland rainforest, navigation will be difficult.

The other fun bit is the rocks. There are so many rocks in our yard. They must have had a rock garden set up along the fence and along some sides of the house, along with a gravel area near the pool. I have no idea what we're supposed to do with these rocks. Maybe I can get a rock tumbler and an acid etching kit and start making smooth rocks with "peace" and "family" and baby names on them so I can sell them on Etsy for two bucks each plus shipping.

Friday, April 27, 2012

Antibody Cake!

To round off a week's worth of laboratory stories, how about some dessert? I know you must be hungry, because I didn't even tell you anything about microbiology and the fun specimens that come into the lab.

My contribution this week was a cake for my coworkers. I went with Funfetti cake, because in my experience nobody hates Funfetti, and it was easier for me to use a box mix than to try my hand at a from-scratch cake. I colored some vanilla frosting so it would have a yellow tint like the plasma we work with, and then I decorated it with antibodies.

I initially thought pretzel sticks would work, but they're too inflexible. My antibodies are made out of Twizzlers Pull-and-Peel (cherry flavor), carefully peeled, cut to size, and pressed into the frosting. Several which were not cut to the right length were eaten in the process. For science.

The little guys around the edges are IgG molecules. They're made of two long "heavy chains" and two small "light chains" and look like little letter "Y"s. The upper tips of the Y, where the light chains and heavy chains are held together with sulfide bonds, is where the antibody magic happens in your immune system. Those tips will recognize and bind antigens, signalling your immune cells to attack. Variations in the amino acids at the antigen-binding region of the antibodies make your immune system capable of mounting a response to pretty much anything nature can throw at it.

The big mess at the middle is an IgM pentamer, which just means five IgM antibodies bound together into an immunological ninja star. IgM is usually the first antibody to respond to an infection. The reason you can be tested for Lyme disease and they can tell the difference between an active infection and a past infection is that the IgM will be present if your body is still fighting in its initial encounter with the bug, while the IgG antibodies will persist for life, hanging around ready to multiply if you're ever re-infected.

I'm pretty certain that cake doesn't have much effect on the immune system, but it sure made us happy.

Thursday, April 26, 2012

Life in a manufacturing lab

My new lab is different: we're not getting patient specimens for testing, and we're not reporting results to doctors. We're a manufacturing lab, taking plasma, unsuitable for donation because of antibodies, and making a useful product out of it. It's an entirely different world from the hospital labs I started in, and I'd like to give you a window so you can peek inside. Here's an anecdote and a description of one of my tasks for you.


One of our big pieces of equipment in the lab is a liquid nitrogen tank, where we keep rare cells, frozen in little vials. We need to go in and retrieve them for testing sometimes, depending on what project is underway, and nobody enjoys doing it, because it's cold in that tank. About -180C on average. We put on big blue gloves worthy of an Antarctic expedition, pop up the lid, and then reach in and pull out one of the vertical racks submerged in liquid nitrogen. Each rack has several shelves, and on each shelf is a little cardboard box containing a selection of vials. We have to pull out the rack, lean it horizontally in the tank so it stays cold, then pull out the right box, tip it to pour out the liquid nitrogen, and then sit it on the tank edge to open it and pick out the right vial.

Of course, as I turned back to put the lid back onto the box of vials, I bumped the box with my clumsy blue gloves and then gasped as the box flipped over into the tank, releasing fifteen vials of valuable cells into the liquid below. First I yelped, then I cursed, then I sighed. Peeking into the tank, I could barely see through the fog created when the cold condenses the water vapor out of the air, but somewhere under the clouds I could see white caps bobbing at the surface of the nitrogen, daring me to reach in for them. Considering my limited options - human hands, even in big antarctic gloves, don't react well to immersion in liquid nitrogen - I went looking for my supervisor.

As it turns out, I wasn't the first to dump vials into the tank, but that didn't make me feel much better. My supervisor rigged a scoop out of a huge pair of pliers and a small sieve, and we went fishing. The floating vials came up pretty easily, but the others were more of a challenge, requiring some digging and scraping of the ice at the bottom to dislodge the vials that had filled with liquid nitrogen and gone down. We got them all, but not until after I knocked one back into the tank while trying to stuff it into the box. Lucky for me, my supervisor found this funny enough to almost choke to death, instead of being frustrated with his twitchy underling.


When I've done everything right, the final product from weeks of effort is a huge glass vessel full of processed and purified serum - it can be up to 30 liters, but usually it's closer to 15 or so. It has preservative in it to prevent microbial growth, but nonetheless, It gets put through an extremely fine filter before we proceed to fill our final 3- or 5-mL product vials.

The vials are filled manually with the help of a small pump and a very coordinated tech who's able to aim the liquid into the vials one at a time, over and over, until they're all full. The filling is done in a fancy "clean room", which means that when I go in to help, I dress up like I'm going to tackle the Andromeda Strain. Fluffy blue hairnet, gloves, mask, hood, booties, and a giant set of white coveralls. Here's an example of the checklist I have to go through to make sure I'm fully covered up:

Those suits are made of a synthetic, plastic-like material so they don't shed fibers, which also makes them very warm! I'm glad I only need to put on the "bunny suit" every few weeks. It's not exactly a flattering look for me. We have a filling session once a month on average, and it can take almost a whole day for the bigger volumes. While we're in the room, we perform environmental monitoring to check for particles and bacteria or molds in the air, and we wipe everything down, especially our hands, regularly with alcohol foam. At the end of the process, we touch microbiology plates with our fingers to see if we did a good job staying clean. If anything grows, we're in trouble. 

As one person fills the vials, someone else puts caps on them and secures them gently. The vials sit snugly against each other, about 250 to a metal tray, so this part is tricky, especially with gloved hands slippery from alcohol gel. Outside of the clean room, we tighten the caps all the way, re-check the count, and then secure the product in a tamper-proof box or wire cage. At this point, the vials are unlabeled, and since a vial of plasma looks like a vial of plasma, we wouldn't be able to tell two products apart if we mixed them up. We keep everything apart and clearly labeled on the outside, and we make sure that the area is completely free of any other product before we take them from their secure storage to label and inspect them.


It's so very different from what I was used to in the hospitals, and yet the concepts are the same. Quality control, attention to details, careful labeling - you'll see this in any lab you visit. While the context might change, and the products and results labs put out will vary, you can be sure the techs behind the work are referencing Standard Operating Procedures and following the rules. Because what we do matters, and we know it.

Wednesday, April 25, 2012

All you ever wanted to know about your urine sample

How much urine do you guys really need? Is it really so easy to contaminate urine?

How much we need depends on exactly why the doctor's making you pee in a cup. If it's for a pregnancy test, we need a few drops, but if it's to check for a urinary tract infection, we need more. Here's why.

When we receive the urine in the lab, it's often in a tube like this, and sometimes a second, smaller tube comes with it, for microbiology.
Obviously, for most of us, it's incredibly hard to pee into such a small target receptacle, so we're handed a cup to use instead. Using a fancy system of urine cups and vacuum tubes, the staff in the ER or doctor's office can transfer urine to a smaller, leakproof container for transport to the lab without ever having to open the cup and risk contamination. Not to mention that the big urine cups are notoriously leaky, which is gross.
The small tube contains 10ml, and that's what we'd ideally like to receive in the lab, because of what we're going to do with it.

The ER normally orders a "urinalysis" or a "urinalysis with microscopic examination". Both of those start off with a chemical analysis, sometimes done on an instrument that aspirates and tests samples on its own, and sometimes done with a manual dipstick. The dipstick has several raised pads, each of which is saturated with a chemical or dye that will react with a different analyte in the urine. 

The average dipstick will check for glucose, bilirubin, urobilinogen, ketones, specific gravity, blood, pH, protein, nitrite, and white blood cells. What does it all mean? 

Specific gravity tells you how concentrated the urine is, and it's very variable depending on how well hydrated a person is. The pH can be vary depending on diet. Bilirubin and urobilinogen can give some information on liver function. The presence of sugar and ketones can indicate diabetes - there shouldn't be sugar in the urine at all unless the blood sugar is very high, and the presence of ketones means that the body isn't able to metabolize sugars and is resorting to breaking down protein and fatty acids. Someone on a zero-carb diet will have ketones in their urine, but they won't have sugar. Protein is a bad sign, because the filtering apparatus in the kidney is normally too small to let proteins through. Proteinuria can be a sign of kidney damage or, in a pregnant woman, pre-eclampsia. Blood is not good to find either, because it can mean kidney damage, with red cells leaking from the blood all the way up in the kidneys, but it could also be from further down the line in the bladder or urethra, or can be a contaminant (when a menstruating woman provides a sample, for example). Nitrite and white cells, together, indicate an infection, because some bacteria produce nitrite as a by-product, and white cells will be around to fight the infection. Not all bacteria will make nitrite, though, so if it's negative you're not necessarily in the clear. That's what the microscopic exam is for.

Once we've done the dipstick test, we only proceed to a microscopic exam if it was ordered, or if one of the parameters on the dipstick test indicates its necessity. Abnormal blood, white cells, nitrite, protein, and glucose can trigger a microscopic exam. In lab-speak, we call this a reflex test, where the result of one test automatically triggers a second test. We centrifuge the specimen, pour off the liquid portion, and examine any sediment from the bottom of the tube. We put a drop on a microscope slide, and look for bacteria, red and white blood cells, and crystals. All this gets reported to the ER or the floor, and the doctor decides whether to order a microbiology culture on the second tube.

All this work requires a "clean catch" specimen, which is why you're handed a little cleansing wipe and told to let the first little bit of urine miss the cup before starting collection. That area of your body is notoriously bacteria-ridden, no matter how clean you think you are, and if the bugs on your skin get into the cup, it can look like you have an infection when you don't. Also, if epithelial (skin) cells cloud the urine, it's hard to look through the mess to find red cells that could indicate a serious problem. If there are too many epis (as we call them) in the specimen, we'll usually ask for a new one, because it's not going to be very useful. Obviously, the problem of blood cells contaminating a specimen of a menstruating woman is a pretty big one, but the doctors know that from the start. If it's extremely important to get a non-contaminated specimen, they can use a catheter and go straight to the bladder, which isn't fun for anyone!

Tuesday, April 24, 2012

Lab Week Q&A - Bar Codes

 Part two of yesterday's question was about bar code labels.

Wait, are the colors of caps consistent across labs? I seriously always just figured it was an internal thing, and the bar codes on the sides were the important parts of communicating info to other labs if blood had to be sent out there.
While the cap color is extremely important in blood collection, because the quality and usability of the specimen depends immensely on how it was collected and stored prior to testing, it doesn't tell the lab what tests to run. The bar code, tied into the Laboratory Information System (LIS), has that job. The way it normally works is that a test is ordered by a physician (usually physically entered into the computer system by a nurse or a member of administrative staff working at the nurses' station), the computer puts that information into a bar code format, which is printed out and brought to the patient's side so the blood can be drawn and the tubes labeled with those bar codes. The bar codes usually list the test and the approved tube color in human-readable language, which is helpful for the staff acquiring the specimens.

Once a tube gets to the lab, the bar code is scanned, acknowledging receipt of the specimen. This time stamp is important because hospitals take turnaround time, or the time it takes from receipt of the specimen to release of a result, very seriously. The scanning is sometimes done manually by an accessioning tech, and then brought to the appropriate area of the lab, but in most larger hospitals, tubes are brought to an automated track system, where they are scanned, sorted, centrifuged if necessary, and brought around the lab where they're sampled directly off the track without a tech ever needing to touch the tube.

Automated track system (Beckman Coulter)

An automated system like that is great for many reasons. It can improve the speed and throughput of the lab, because nothing needs to wait for a tech to bring it to the next instrument. It's good for safety, because any time you can eliminate contact between a person and a blood specimen, you've eliminated a chance of exposure to a bloodborne pathogen like HIV or Hepatitis B. It's got its drawbacks, however.

One big issue is that the instrument doesn't look at the tubes. It only sees bar codes. If a specimen somehow sneaks by without getting de-capped, the specimen probe on the instrument will smash into the cap, expecting a clear path to the serum. The probe has a liquid sensor, and only starts aspirating serum when it feels the top of the liquid. It's expecting the tube to be full - if it's a very short draw, there's a risk that it will keep going and suck up the gel separator in the tube, gumming up all the tubing in the instrument and shutting it down for cleaning. That's why our lab had this sign posted by the inlet of the automated track:
Inlet of the automated line, with warnings!

Also, because all the instrument knows is the bar code, if someone puts the wrong label on a tube, there's no easy way to know unless someone is very careful about checking every tube before it gets put on the line. Ideally, they would all get a check, but when the workload is very high, some can get missed. Normally a label error is immediately apparent, like when a lavender tube, which is supposed to be diverted to hematology, chugs along the track towards the centrifuge to be spun - it's easy to spot because it's shorter than the chemistry tubes. If it gets all the way to the instrument without raising suspicions, say, if a tall pink top is labeled with a Chem-7 bar code, the results will cause the tech to pull the tube off the line and have a look at it. The potassium will be so high as to be incompatible with life!

Bar codes make it easier for the lab staff, because it saves us the trouble of having to program all the tests in manually for every single specimen. It saves us a lot of time when the instrument can read the orders and get the tests done. However, when specimens are sent out to other reference labs for more esoteric testing, they can't read the barcodes produced by our internal computer system. We have to fill out paper requisition forms and then send the tubes off (or poured-off serum) in special packaging, sometimes on dry ice, sometimes at room temperature, whatever the reference lab requests. Some hospitals have the system computerized and can fill out online requisitions and print out reference-lab-specific bar codes for the specimens - because the reference lab will have their own computer system and won't be able to use the original bar codes. It's like our bar codes are in German, but the other lab needs them to be in Finnish. We can either give them all the information on paper and they'll make their own Finnish labels when they get the specimen, or we can use their software to do that ourselves. That requires a special arrangement between the two labs, and not everybody has the resources to do it.

Even with the help of the bar codes, we still need to order things manually sometimes when tests are added on later, or if tests need to be repeated, but the only time the lab does everything manually is when the computer system goes down.

Two bad things can happen with the computers. The hospital system can go down, or the lab system can go down. In our facility, it was two separate systems, so although they could speak to each other, either one could die independently, leaving us with two different kinds of messes. If the hospital system goes down, the floors send down the tubes with patient-information labels that look like the patients' hospital armband. They include a "downtime" order form where they can check off all the tests they want run. Then we can order the labs on our end, getting bar codes, sticking them over the other labels, and proceeding as usual. The instruments still know what to do, the results still come onto our computer screens for analysis, and we can call, or print out and fax, the results to the floors. That's tedious, but not terrible. When the lab system goes down, it's chaos. We log receipt manually and program tests manually. We keep reference sheets handy to confirm panic values and normal ranges, and we fend off calls from the floors asking why everything is taking so long. We keep piles of instrument printouts so we can later manually enter everything into the computer. Some instruments will allow you to re-send the data once the system is back up, but not all of them. We love bar codes and computers. Very, very much.

Monday, April 23, 2012

Lab Week Q&A - Color coded blood collection tubes

As much as lab week is about celebrating the work of laboratory professionals, I see it as an opportunity to educate people about what happens in a lab. You get blood drawn, and you get results back, but what happens in between? I hope that I do a good job explaining things - please let me know in the comments if there's anything I missed or that you'd like to know more about.

The question for today is:

Wait, are the colors of caps consistent across labs? I seriously always just figured it was an internal thing, and the bar codes on the sides were the important parts of communicating info to other labs if blood had to be sent out there.
I'm going to break this into two parts, about tube colors and bar codes, and address each one in a separate post. I'll start with the colors.

If you've ever had lab work drawn, whether at a doctor's office, a hospital, or an external collection site like LabCorp, you may have noticed that when they take more than one tube of blood, the caps on the tubes are usually different colors. That's because there are different requirements for how the blood is treated and transported before it gets tested.

Common tube colors - from
Cap color is indeed consistent across labs. More accurately, you could say that it's consistent among the major manufacturers of blood collection tubes. It's possible that the manufacturers are doing this voluntarily, but I suspect there may be a federal entity like the Food and Drug Administration (FDA) involved, since it could hugely affect patient safety. Even if there is no official rule about cap color in the Code of Federal Regulations, I suspect that someone trying to market an EDTA tube with a green cap would find a very grumpy FDA inspector on their case.

Now, EDTA (ethylenediaminetetraacetic acid) probably doesn't mean much to you, yet. I'm here to tell you that it's an anticoagulant, one of many, used in blood collection tubes. Depending on what test is being run, we want the blood to act in different ways. I'll go over the most commonly used tubes and explain what the cap colors mean and what sort of tests each type is normally used for.

Pink or Lavender - EDTA

EDTA tube - from

Both pink and lavender tubes contain EDTA, which is a chemical that binds with and ties up calcium ions. Because blood needs calcium ions present in order to initiate the clotting process, blood that is collected into a pink or lavender top tube (and well mixed) will remain liquid.

Lavender tubes are generally used for complete blood counts (often shortened to CBC), which includes things like white cell and platelet count, and hemoglobin. This makes sense - if we're trying to do a platelet count, we need the blood to remain liquid, since a clot is going to tie up a bunch of platelets. If a number of blood cells are tied up in a clot and unavailable for the instrument to count, then the count will seem a lot lower than it really is. A CBC is one of the most commonly ordered tests, because it can tell a doctor about infection (high white cell count) or anemia (low red cell count), which are common reasons for doctor visits. You're very likely to have a lavender tube drawn if you're getting lab work done.

The main difference between the two colors is that the pink top tubes are generally bigger, and get spun down in a centrifuge to separate the plasma from the cells. The pink tubes are primarily used in the blood bank, because we run tests on both the cell part and the plasma part of the blood. We could use lavender top tubes, but we like to have a bigger volume of specimen to work with, in case we need to start cross-matching blood for the patient, which will use up the plasma. Also, the rules for labeling blood bank specimens are usually more strict, and having a bigger tube leaves more room to write out the patient's information.

Light Blue - Sodium Citrate

Sodium Citrate tubes - from
Blue top tubes are used primarily in coagulation studies, like monitoring heparin or warfarin therapy, or looking for clotting disorders before a patient goes to surgery. Sodium citrate, like EDTA, also prevents clotting by tying up calcium ions, but it's better than EDTA in preserving the rest of the blood's clotting factors. The tubes are always the same size, and contain a set amount of sodium citrate. Most coagulation tests start by adding some calcium back in and seeing how long it takes for the blood to clot, so it's extremely important to fill the tubes all the way. An underfilled tube will have an excess of sodium citrate, which will tie up some of the calcium the instrument is adding in, which will make it look like the blood's taking a very long time to clot. If you aren't on blood thinners, and you're not showing signs of a clotting disorder, you aren't likely to see the phlebotomist pull out a blue tube.

Light Green - Heparin

Heparin tube with gel separator - from
These were the most commonly used tubes in the chemistry section of the hospital lab. They're used for glucose (blood sugar) testing, electrolytes like sodium and potassium, and other important analytes like cholesterol, liver enzymes, and cardiac markers that can indicate a heart attack. This anticoagulant is usually a Lithium-Heparin salt, instead of a potassium or sodium salt, because most basic metabolic profiles (you'll sometimes hear them called a Chem-7 or Chem-some-other-number on TV medical shows) will measure potassium and sodium, and we don't want to falsely increase those numbers with our anticoagulant. We also can't use EDTA, because the calcium would look too low. 
Because chemistry testing is focused on the plasma, the blood is centrifuged to get the cells out of the way. Some tubes go an extra step with a built-in gel barrier, which keeps the cell portion trapped below so that even if you invert the tube, the cells stay put. This makes it easier to aliquot the sample (take small volumes from the main tube for other testing) without disturbing the cells and making it necessary to spin the tube again.

Gold - Gel Separator, No Additives
Gold tube, no additive - from

In situations where it's okay for the blood to be clotted, a gold top tube can be used. It has no anticoagulant, so after the blood has been in the tube for a few minutes, it will form a nearly solid clot. Once spun, the tube will have cells and serum separated by a gel barrier, which makes it easy to pour the serum off into other tubes for separate tests. These tubes are often used when the serum is to be sent to an outside lab for special testing (anything not done at the lab where it's drawn), because it's easier to pour the serum into transport tubes for refrigeration or freezing, and they're a little cheaper because they have no additives. 

Many labs use these as their workhorse tubes, accepting them instead of heparin tubes for chemistry workups. I don't actually know why the lab I was working in used the green tubes for most of the chemistry - a lot depends on the instruments being used in the lab and whether they have specifications for the test material. If your test's instructions say it needs to be a heparin tube, then that's what you should use, because the results may not be reliable if you use something else. Also, it's better for the patient if we can run several tests off of one tube, and not just to keep costs down. Repeated blood draws can lead to bruising, and if excessive, to phlebotomy-induced anemia. So, if you can choose to use either a green or a gold tube for a certain test, because both are allowed by the instrument's specifications, but another important test in the lab needs to be on a green top, it may make sense to bundle those tests together onto one tube.

Other - Special Cases
Some other colors are out there, but they're used infrequently and you're not likely to see them unless you're having fairly rare tests done. In our lab, dark blue tubes were used detection of heavy metals like copper or lead, because the tubes and interior of the caps were free of trace metals. Red top tubes had no additives, like the gold tubes, but contained no gel separator, so they could be used for some therapeutic drug levels - the gel has a tendency to absorb some drugs over time, so a red top would be more accurate in those cases. Gray tubes were used for lactic acid levels, but some places use them for glucose, because the potassium oxalate anticoagulant in the tubes stops the red cells from using it all up.

While different labs will use the same tubes for different tests, depending on their methodologies, a lavender top tube in one hospital will contain the same additives as one in any doctor's office. It's common sense, really - you don't want a part-time employee who works at two different facilities to get confused and use the wrong tube for a specimen collection, because it's what he's used to at the other job. Yes, it gets looked at in the lab, but we're all human and sometimes a wrong tube can go on an instrument, and since all the instrument does is read a bar code and perform the tests it's instructed to, you'll still get a result, and it may be very wrong. Consistency is key to medical and laboratory safety.

Sunday, April 22, 2012

Happy Lab Week!!

Happy National Medical Laboratory Professionals Week!!

Yes, it starts on a weekend. Someone's got to keep the lab running, you know. A hospital lab never closes.

It's a week for celebrating all those who work in laboratories - phlebotomists, cytotechnologists, histotechnologists, pathologist's assistants, medical technologists and technicians of all stripes. Hug a tech this week if you can find one. Especially if it's me. I like hugs.

This past year has taught me some things about my profession. Namely, that not everyone works in a hospital. Obviously, I knew that - in med tech school they told us we could work in all sorts of places. But when everyone who got hired right after graduation found a job in a hospital lab, it was made pretty obvious to me that most of the jobs were in hospitals. I followed the tide and worked in a hospital too, for quite a while. Two hospitals, in fact. I started in a blood bank in a big Montreal hospital, working any shift they had for me, going from days to nights to evenings within a single week sometimes. Then I got to Maryland and worked in a core lab, doing everything a med tech could possibly do, from blood bank to chemistry to basic microbiology and everything in between. But when it was time for a lifestyle change, I looked outside my comfortable box and discovered that a med tech can still be a med tech outside of the hospital basement.

Where I am now is a strange hybrid between a manufacturing company and a blood bank. I'm not dealing with bleeding patients; instead, I'm making products that will be used in reference labs across the country so that people there can do a better job dealing with bleeding patients. It's fascinating and I'm learning a lot, especially when it comes to quality assurance, documentation, and Good Manufacturing Practice (GMP). Almost everyone there has the same degree as I do (plus some extras), and many of them also started in hospital labs. Now, they're submitting paperwork to the FDA, developing new products, performing extensive environmental monitoring, filling vials in a pristine clean-room, and even controlling document distribution. What a different world!

I had applied for a job at LabCorp previously, and that job would have had me running a STAT lab, drawing blood, and even taking patients' vital signs like blood pressure and temperature. For someone who likes more patient contact, a job like that could be a dream. Not so for me.

Looking over the possibilities in the online job listings, I could work in a fertility clinic, doing semen analysis and bloodwork, and assisting in preservation of eggs and embryos. I could work for the Food and Drug Administration in one of their labs, testing products and water for bacteria, or go out and do inspections of other labs. I could work for one of the companies making laboratory instruments, testing them, selling them, or training people how to use them.  I could branch out into computers and work with a hospital's lab information system. I could teach medical technology at a university. I could get an advanced certification and become a manager somewhere. I could work in quality assurance, public health, forensic labs... so many possibilities. I'd need some extra education for some of these, but it's wonderful to know how many options are out there for someone with my degree. And if all else fails, there are always the hospital labs, chronically understaffed and always looking for fresh techs. Even if I'd have to work nights or weekends, I am reassured by the fact that I will always be able to find a way to make a living doing what I enjoy. I'm grateful for that.

Friday, April 20, 2012

This needs to be a thing

Giggling at my husband reading things in silly voices, and a Robot Chicken Star Wars discussion in the Target parking lot, brought about the opinion that Emperor Palpatine as a checkout guy at Target would be goddamn hysterical.

Why? Because this, that's why:

"Take your pen. Sign your name with it. Then your journey towards your transaction will be complete."

This is likely only funny to myself, but I'm okay with that.

Tuesday, April 17, 2012

Lab Week is Nearly Upon Us!

I've linked to this powerpoint-turned-video before, but in light of National Medical Laboratory Professionals Week coming up on April 22nd, I would like to share it again.

I created this presentation last year while I was still working in a hospital lab. It was intended as an overview of a medical technologist's daily routine, and my supervisors liked it enough that it was shared with the rest of the hospital staff over the hospital's main intranet page. It's not a fancy video with music and sound, because I'm not talented in those ways - I didn't create this, or link to it here or on Facebook, with a goal of self-promotion. If it helps a single person better understand what medical technologists do, then I'm proud of my work and it has served its purpose. If it steers one curious student towards the profession, all the better.

Since creating this, I've moved on to a new career, even though I'm still called a medical technologist. The change in perspective has showed me new sides of the profession and how it's not necessarily all about the hospital.

Next week's posts will be lab-related, in honor of National Medical Laboratory Professionals Week 2012. I would love some reader input and suggestions for topics, because I want to educate folks about the lab, what goes on there, and what it's like to be a part of the hidden side of medicine. So, please, ask me why the phlebotomist really needs all those tubes, and what the colors of the caps mean, or why sometimes they wrap the tubes in foil. Ask me why lab results take so long, and what in the world they're doing with your cup of urine when you leave it behind the little door. I'm interested in all questions, comments, suggestions and ideas.

Monday, April 16, 2012

JoCo Cruise Crazy 2012, Leftovers

Paul's mom, Mrs. Sabourin, has a pirate's bloodlust. When we were on the bow of the ship for the group photo, I was standing next to her for a few minutes, and when I pointed out a small sandy island nearby, she said "Let's claim it." When I reminded her that there there were probably already people living on it, she looked around at the doughy Sea Monkeys surrounding her and declared "We can take 'em".

We met Jonathan Coulton on the first day, enjoying drinks by the Lido pool. He came up to us and shook our hands, after which he told us "There, I just gave you diarrhea. That is why you never shake hands on a cruise ship."

I learned that the appropriate term for people from Saskatoon is "Saskatonians", and calling them "Saskatooners", while hysterically funny to me, is wrong and likely a little rude. But they wouldn't tell you that, of course. They'll just smile politely and judge you internally.

While we were taking our scuba lessons in the pool, a giant iguana decided he was tired of hanging out in the tree, and belly-flopped into the water next to us.

I'm not sure who created it, but a "burn" gesture was born on this cruise. Used when a particularly good burn is issued, it consists of covering your mouth in mock horror and flicking your hand to divert any burn-ricochet that may come towards you, innocent witness to the spectacular burn.

John Hodgman always sat in the same place for every show - a balcony area christened the "Hodge Pod". He sat quite regally in his Pod, sometimes rising and extending his hands in an attempt to zap the performers with Palpatine-esque finger-lightning.

I'm sure there's more, but it's time to put this cruise to bed and move on to other things. Thanks for the good times, JCCC2. We'll always have Aruba.

Sunday, April 15, 2012

JoCo Cruise Crazy 2012, Day 7

All good things do come to an end, and so it was with the cruise. Day 7 was our last day at sea, and you could tell people were winding down and starting to feel the crushing inevitability of the Westerdam's return to Ft Lauderdale and our return to a reality without free ice cream, Famous People dance parties, and casual fez-wear.

I completely missed the morning event, because after a week's worth of extremely little sleep, my body would not cooperate and get out of bed after the wakeup call. The thing with a wakeup call is that it has no snooze button. They need to work on that. So, because I was snoring away in my shoebox of a room, I missed Paul and Storm recording a live podcast. I don't feel too horrible about it, because I got to listen to it a few weeks after the cruise and have a little moment of reminiscing while driving to work in bad traffic, but it sounds like the live audience had a blast, and I'm sorry I missed it.

The event of the day was the Big Event - the man, the beard, Jonathan Coulton, live and awesome. People were lining up in the hallways outside the Vista Lounge to get the best seats, but since we were tired, we came later, took mediocre seats, and still enjoyed the show tremendously. JoCo is so much fun in a live show. He had a band with him for half of the performance, which was neat and gave the show more of a rockstar vibe, but I think I liked his solo stuff better, since it's what I'm more familiar with. I'm sure the newer stuff will grow on me, and certainly his new album is spectacular, but I enjoy seeing him onstage with his guitar, with no extra bells and whistles (except for the Zendrum for Mr Fancy Pants, of course).

When his show was done, it was time to start packing and getting mentally prepared for the early-morning disembarkation ahead of us. I had a sad.

We had our Saskatoon buddies come by our shoebox to help us finish off some wine we'd brought aboard, and we had a wonderful evening with them, including our last fancy meal in the Monkey Pen of the main dining room. There was a big goodbye party by the pool that night, the "So Long and Thanks for all the Booze" reception, where we had a last chance to chat with some of the Famous People and mingle with Sea Monkeys, exchanging business cards and email addresses as seriously as little kids exchange information on the last day of summer camp.

That's what it felt like that night at the party, like it was our last night at camp and our parents were coming to pick us up in the morning.

I want to sign on for JoCo Cruise Crazy III, next February, but have to wait and see whether everything lines up right. I'm glad I got to experience this sort of thing at least once in my life, and I'm grateful to Paul and Storm, JoCo, and all the behind-the-scenes folks who made it happen. Even if I never attend another huge nerd boat party, I've got the memories from this one, and I'm happy.

Saturday, April 14, 2012

JoCo Cruise Crazy 2012, Day 6

The final two days of the cruise were spent at sea, while the ship made its way back to Florida.

There was a morning show featuring Vi Hart and David Rees, but I was so tired I don't remember very much of it. David Rees read from his new book about artisanal pencil sharpening, and demonstrated some intricate techniques for the audience, then Vi Hart played us some mathematical piano and got people to hop around on stage to demonstrate patterns and symmetry. Both of these people are talented and funny, but I didn't feel like either of their acts translated well to the big stage. I feel bad saying that, because I really did enjoy the performances, but they're both performers who seem to come across better in different media. Vi's blog and videos are wonderful, and I'm sure David's book is very funny, but having them on a huge stage at 9am was an odd decision.

Thanks to popular demand, Marian Call arranged an encore performance for her doting fans, and a few of us squeezed into the Northern Lights disco for an intimate little show. She's stellar live. I hope she comes to this area soon so I can drag some friends to her show and make them love her. Her guitarist, Scott Barkan, also did a solo show for the Sea Monkeys, but I was wiped out and needed a nap more than I needed more music. I'm told I missed a great show, and I hope someone got it on video.

That night, it was the show of Johns. John Hodgman, the Deranged Millionaire, spoke to us about his new book and the end of the world (his new book describes the end of the world, it does not cause it directly). I enjoyed his comedy tremendously - I'm used to seeing him playing a character, on the Daily Show, and he was a lot more real on the cruise and thus somehow funnier to me. After that, John Roderick, from the band The Long Winters, took the stage. He'd joined other performers in their shows here and there, so I felt like we'd already seen him perform, but his solo show was great. I'd never heard of The Long Winters before, but I've got their albums on my wishlist now. At the end of his show, he brought Jonathan Coulton and his band, and Paul and Storm, onstage to join him in The Commander Thinks Aloud, and the performance moved us all to silence.

Finally, after another formal dinner in the fancy dining room, it was time for The 2nd Annual Paul F. Tompkins Memorial Moustache Formal and Feztravaganza. They like long fancy names in JoCo Cruise Land. People were gussied up, drinking free booze, and sporting creative moustaches.

Mine was a simple stick-on moustache, but my husband, already possessing facial hair of his own, opted for a 'stache-on-a-stick. There were moustaches of every conceivable type and color, even some made out of rubbery tentacles. I will need to step up my game for the next cruise. The fezzes were impressive, too, many of them handmade and quite elaborate. Storm (of Paul and Storm fame), wore a fez with a built in percolator, engineered by Grant Imahara of the Mythbusters. I hang my fezless head in shame, and I pledge to have appropriate headgear for JCCC3.

Friday, April 13, 2012

JoCo Cruise Crazy 2012, Day 5 (part 2 of 2)

What a day.

You'd think Day 5 couldn't get better than giving a dolphin a belly rub, but the thing about JoCoCruiseCrazyII was that it kept getting better.

Sunburned and exhausted, we settled in for what was likely the most-anticipated show for both of us. Dave was excited to see nerdcore rapper MC Frontalot, and I was all ears to listen to Wil Wheaton read us some of his stuff. You may recall I was quite excited, and doublequite nervous, about the possibility of meeting Wil Wheaton on this cruise. More on that later.

Wil started the show, reading us excerpts from his books and blog posts, sharing a little bit of himself with an appreciative and responsive audience. I really enjoyed hearing him, especially because I'd read some of it before, and it was good to hear him tell the stories, with asides, footnotes, and emotion. I wish he'd had more time on stage!

MC Frontalot put on a wonderful show, too, but rap, whether of the nerdcore or mainstream variety, has never been my thing. They just go too fast and I miss half of the words and get frustrated, because I am lame. But you shouldn't be like me - this guy is incredibly creative and talented, not to mention very funny in person, and you should at least give his music a listen to see if it's your sort of thing. The audio of the cruise performances isn't very good, so here's a link to one of his songs, First World Problems, on Youtube instead.

And now comes the best part of the cruise, in my mind. Dave and I spent most of our evening with some wonderful people from Saskatoon, drinking far too many Red Stag Derbies in Ten-Forward. By Ten-Forward, I mean the Westerdam's Crow's Nest bar, located on Deck 10, at the front of the ship. Given its location, I don't see how you could expect a ship full of nerds not to find a label-maker to change the name on the ship's maps by all the elevator bays. Also, for reference, here is the Crow's Nest bar, from Holland America's webpage:

And, for comparison, Ten Forward, on the Enterprise:It's uncanny.

Anyway, after racing to the bar to stock up on Red Stag Derbies and strawberry daiquiris before the two-for-one special ended, we hung out in Ten-Forward and waited until karaoke time. Because yes, there were two karaoke nights to be enjoyed on this cruise!

The place was packed by the time we showed up, so we were stuck standing in the back near the bar, barely able to see the stage. We could hear just fine, though, and as it turns out we had a wonderful view of the Famous People hanging out and being silly at the bar. On this night, I was warned in the most serious of mock serious tones, never to get between a Wheaton and his scotch. On this night, I witnessed John Hodgman belting out Harvey Danger's Flagpole Sitta. On this night I saw MC Frontalot and Wil Wheaton sing along to Hit Me Baby One More Time, along with full tipsy choreography. This was the night I decided I needed to be on JoCoCruiseCrazyIII.

Wednesday, April 11, 2012

JoCo Cruise Crazy 2012, Day 5 (part 1 of 2)

Why didn't the Beach Boys want to take me to Curacao? Is it because they're too lazy to find a good rhyme?* This island deserves to be included in every list of gorgeous tropical destinations set to music. I could have stood on this bridge for hours, enjoying this view. This was taken just outside the site of our excursion for the day, the Curacao Sea Aquarium, home of the Dolphin Academy.

I struggled for a long time about whether or not I wanted to take the opportunity, while in the Caribbean, to swim with dolphins. Holland America's excursions offered several levels of dolphin interaction, from watching a dolphin show at the aquarium, to getting flippers on and jumping into the lagoon with the animals. My biggest concern was whether it's ethical to swim with these captive creatures for our own amusement - I've heard stories about dolphins being mistreated, and I hated the thought of contributing to an unethical industry. I did a lot of research before finally deciding I was comfortable signing up for the "dolphin encounter" at this specific aquarium, which would put me in the water on a platform, with a dolphin trainer bringing one of the dolphins over for a closeup.

We were told not to wear sunscreen because it would irritate the dolphins' skin, but with our skin already as red as it was, we went ahead and put a little on anyway - on our faces and shoulders, mostly. Apologies if we gave any dolphins sea-eczema, but we just couldn't bear to get more burned. After the pre-encounter briefing and signing of the "we won't sue if we die here" waivers, the group was herded out to the lagoon, where we saw a group of splashing dolphins, with their silvery skin, their bottle noses, and their big pink dolphin wangs. Yes, they were rocking out with their... snorkels... out. I'm not sure whether there were females involved, or whether all of the participants were consenting, but to whom do you report when you witness a possible cetacean rape? The trainers completely ignored the goings-on, so it can't have been too unusual, but I can tell you that I spent the rest of the day very very glad that I decided against actually joining these huge horny bastards on their turf. (Their surf?)

Pasku, "our" dolphin, was young, playful, and disobedient, swimming off all the time to bother his favorite trainer, who was working with others across the lagoon. Only three years old, he was already huge, and made of solid muscle. The trainer kept having to whistle and bribe Pasku with fish, but eventually everyone in our group got a chance to meet him, pet him, and "chat" with him. It was really an incredible experience, and I'm so glad I had the chance to do it. The best part was when Pasku rolled over for belly rubs, which apparently dolphins love as much as cats do.

We took some time to see the rest of the aquarium, skipping the kiosk where they sell professional photos of your dolphin encounter for a whole lot of money. I bought a real sugar Coke at the little cafeteria, which was as delicious and refreshing as it sounds. After the taxi van brought us back into town, we shopped for souvenirs but quickly retreated to the Westerdam to nurse our sunburns, which by that time were pretty painful. I would have liked to see more of the city and the island - these 8-hour stopovers are just enough to give you a taste, but it's not long enough to see much beyond the tourist traps, especially if it's your first time.

*I'm going with "Barbados, Curacao, be my lusty beach frau." This stuff writes itself.

Monday, April 02, 2012

JoCo Cruise Crazy 2012, Day 4

Hello, Aruba!

I had no plans for Aruba, because I was a big chicken and didn't make up my mind to sign up for the Introduction to Scuba Diving excursion until it was too late. I was on the waiting list, but Aruba Day arrived with no word that I'd been bumped up, so my vague idea was to hound the excursion staff until someone let me go try on some flippers. When we got off the ship, the cruise terminal was filled with tables to sign in for excursions, so I got my "pretty please" face on, cranked up the politeness, and haunted the Scuba table so expertly that I expected someone to be by with a Proton Pack to dispose of me. They took my name, and told me it was full, and I had to wait past the start time of the excursion to see if anyone didn't show up. I waited, and waited, and as the clock inched past 2pm, they sent my husband off to the other side of the island with the rest of the divers in a brightly-colored shuttle, leaving me all alone.

The surprise and happiness in my husband's eyes as I got off the shuttle to join the Scuba group is one of my most cherished memories from this cruise.

As it turns out, neither of us are Scuba divers. Once I got into the pool and started using the equipment, I was really excited, but I just couldn't get comfortable breathing from the regulator underwater. I was fine with just my face under the surface, but trying to sit on the pool bottom, with all that water over me, and my only air coming from a tank on my back... I freaked out more than I really want to admit. I felt like I could not get enough air, no matter how hard I tried to inhale, and that just got me hyperventilating, which is not good. Dave had issues with clearing his mask, so he ended up not being able to dive, either.

The instructors see that all the time, so instead of making fun of the sissies, they handed us snorkeling gear and let us float on the waves while the real divers poked around the bottom of the sea. I'd never snorkeled before, but it was a breeze, and it was an amazing experience. We were above the Pedernales, a WW2 oil tanker that was taken out by a U-boat in 1942 and whose wrecked middle section was left as a target for the Dutch navy to practice on. It was so close to the surface that I could stand on a section of it and have my head above water. It's been sitting there long enough for coral to start moving in, and little schools of blue and yellow fish use it as a hiding place to avoid predators. I am still amazed at how bright tropical fish are. Also, at how much salt water burns when it's in your nose.

We were in Aruba until late that night, so we had a perfect chance to watch the sunset from the island. We had some drinks at a bar near the water and watched the sky burn orange behind the Westerdam before we headed in.