Lab Work

I wish I had learned more in medical school.

I did learn, what should have been a very valuable lesson, quite early on during the laboratory medicine part of our pathology course. What I was taught was:

Don't order any investigation where the result (positive or negative) will have no influence on the management of the patient.

With that knowledge in hand out I went into the world.

I learned another thing along the way.

If after talking to and examining the patient, you have not the foggiest what could be wrong, no lab test is going to help you.

Now if you read this blog, you will know that collecting blood for the lab was one of my most favourite parts of internship. Through sheer stupidity I actually used elective time to do orthopaedics thinking I would actually learn something useful. Now on ortho, every admitted patient (and back then there was very little day surgery and no same day admission) whether he was 19 or 90 got a laboratory panel of 24 tests known as the SMAC. This required 5 tubes of blood to be collected. So on my first or second day, I asked the resident, "why do we do so many tests on apparently healthy patients?". He looked me in the eye and said, "Anaesthesia wants them". Naturally all these patients were admitted after 1500 when the lab blood collection went home, which left the blood collection to the interns.

Of course "normal" results are in fact the range that 95% of healthy assymptomatic patients fall into. This means that 5% of otherwise normal patients will have an abnormal result to a test. If you order 24 tests, there is an absolute certainty that at least one will be abnormal. These abnormal tests have to followed up on which of course means more blood work.

Now did "Anaesthesia" really want them. Apparently not as I learned a few years later when I read the guidelines for routine lab work. Here are the current ones:

Now I was able to find these in about 30 seconds because I know where to look for them. If I had googled pre-operative blood work it is little more complicated but by simply looking up the guidelines of your national anaes. society, it should be quite easy. Or you could ask your anaesthesia department.

But why do I even give a shit?

1. I pay taxes

Most healthcare is publicly funded in Canada. A significant amount is publicly funded in the US. I want my tax dollars spend on treating patients not on lab work! As an aside, much of the blood work in my province is done by a private company. Do you thing they have any interest in reducing lab work?

2. Healthcare is a zero sum game

Even in the US, there is a finite amount of money that can be spent on healthcare. That means money spent in one area is money that will not be spent in other areas. Every dollar spent on unnecessary lab work is a dollar that could be spent on something useful like chronic pain.

3. It holds up things.

How often has your day in the OR been disrupted by a cancellation or postponement due to an abnomral lab test that shouldn't have been ordered that has absolutely no bearing on the patient's ability to tolerate surgery. Just the same, you have to cancel the case, or wait while the test is repeated or the necessary follow-up tests are done. Many years ago I saw a patient who had been cancelled a month ago because of an abnormal gamma GT that someone had ordered pre-op. It was elevated so she was cancelled, went for the million dollar work-up which was of course normal and was re-booked. Of course somebody ordered the gamma GT again which was still elevated. Remembering from my time in family practice that this test is a marker for alcohol abuse (or use?) I asked her if perhaps she might have had a glass of wine the night before her testing and lo and behold she said yes. I put her to sleep and she survived despite her abnormal lab test.

4. It delays necessary lab work.
A classic example is the PT/PTT. Nobody would deny the benefit of these tests in following response to anti-coagulant therapy. There are also important in the management of an evolving coagulopathy or in monitoring whether a patient has been off his anti-coagulants long enought to do surgery or stick a needle in. Except...when you order the stat PT/PTT you really need, it is going to be queued up behind all the "baseline" PT/PTTs that have been ordered. Therefore you are going to get back your PT/PTT long after you have already bit the bullet and given the FFP your patient may or may not have needed.

5. Nobody looks at it or does anything about it
Sadly, that is the case. We order all this stuff and it gets filed in the chart and nobody looks at it. This includes abnormal lab work which frequently isn't followed up on. Chest X-rays are the classic which are often ordered pre-op and reported on post-op. As I found out as a resident, actually going to X-ray and looking at the CXR is no help. The one and only time I tried that, the tech at the film library laughed at me. Actually at our hospital, CXRs are available on-line now if I could just find the time to fill out the stupid form, make up a password etc. EKGs of course go off to be reported by the cardiologist which means they sit on someone's desk until look after the surgery.

6. Surgeons actually think lab work is a substitute for a proper history and physical.
The last time I cancelled somebody as medically unfit, the surgeon's whine was, "But I ordered a cardiogram". Further people think that lab work is a static thing, like the fact that the patient's K was normal on admission, means his K is still normal after he's been vomitting for 3 days.

7. Politicians know we order too much lab work and use it as a stick to beat us on the head when we complain about lack of funding in other areas. "The ER is full of patients waiting to be admitted?. That's because you doctors order too many blood tests".

8. It leads to more unnecessary testing and interventions

I have a personal story here. My first born was born at term after an uneventful labour and was normal size for gestation. Despite this somebody decided he needed to have a blood glucose done. It was something like 3.0 which would be low for an adult but normal for a full-term neonate (because of this episode the normal range for neonates of 2.5-3.5 which of course I had to know for my recently completed written exams has stayed in my mind). Of course the lab reported that number as low using the adult range, so the first thing the nurses did was to feed him some glucose and water. This meant when my wife woke up a few hours later with swollen boobs, our son didn't want to feed. It also meant he got an extra heel prick the next day to see if his blood glucose was still "abnormal".

I fought the lab and ... hey I won this time

One of my favourite tasks as an intern was acting as the after hours (and frequently during hours) blood collection service. Right up there with IVs and manual disempactions.

We all remember being called to draw blood from a patient. The patient was either:

1. A little old lady covered in bruises on all four limbs from IV and blood collections.
2. A heavy smoker with no veins.
3. A child on chemo with a severe needle phobia.

So after multiple stabs and tears you would fill the multiple different coloured tubes that the nurse handed you. An hour later you would be paged back to the same patient to draw more blood because:

1. There wasn't enough blood in the tube
2. There was too much blood in the tube
3. You collected blood in the wrong coloured tube (I used to fill one of each colour just in case)
4. The specimen was not properly labelled
5. The sample was "hemolyzed".

Of course it is over 25 years since I was an intern so I should have gotten over it by now. I still of course collect blood from patients under anaesthesia, and very rarely get called to the floor because no-one else can get blood. I also collect blood from nurses who got a needle stick which brings me to my story.

Now for several years I have resolved to wear gloves when starting IVs but this year I actually started doing so. The other day I went to start on IV on my first patient of the day. He was a little difficult and I had to try a second time but I got the second IV in. I am not the neatest person but I do make a point of being responsible for my own sharps. I picked up the two IV needles with me gloved hand and walked back towards my sharps container. That was when I felt a little prick (not the surgeon) and when I took off my glove I could see a little break in the skin.

Oh shit.

The patient had no obvious risk factors and no visible tattoos. Nevertheless I felt that I should draw blood from him and myself. At our hospital we have a needlestick protocol. You get a ziplocked bag with two tubes, one for the patient and one for you. There are two reqs one for the patient and one for you. You put everything in the same bag and it goes off to staff health.

The patient was still under some I drew some blood from a vein and put it into one of the tubes which I labelled with a sticker. I put his sticker on the req. Finding somebody to draw blood from me was harder. The OR nurses didn't want to do it. Recovery room nurses are good at drawing blood but the req had written across it in handwriting "please do not ask recovery room to draw blood". I finally found another anesthetist between cases. I labelled the tube with my name, filled out the req including my name, my date of birth and my healthcare number. Everything, mine and patient's blood went into the ziplock bag and off to staff health. Now as I was labelling my tube, I thought back to those happy times as an intern acting as the afterhours blood collection and recollection service.

Not much to my surprise, I got a call from the staff health nurse about 30 minutes later stating that the lab would not process my sample because it was not labelled properly. I suggested maybe she should call the lab and straighten things out with them as there were only two samples in a zip-locked bag and one was labelled with the patient's label, the other one had my name it. She asked if I was concerned about the patient's risk factors. I asked if she had never heard of universal precautions?

Now I could have just found somebody to draw another sample, but hey it's my blood, my integrity was violated to get the sample, they should process it. So I phoned the lab director who actually had heard about the fuss already. He said he would bring the sample to the OR and I could label it properly. About five minutes later he phoned back saying that the lab tech had told him, there was no way even if it was relabelled that they would process it.

I asked him, "Are you a physician?" He said "yes". I asked "and you have done a pathology residency?" Yes again. So says I. You have over ten years of post high school training and you are letting someone who graduated from a two year technical school telling you what you can do.

One hour later, he brought the tube to the OR and we relabled it.
2
Score: Lab 217 BH 1. But at least I'm on the board.

And by the way the patient was negative.