Sorry for going AWOL over the last two weeks … I have had a lot going on. Let’s try to catch up on things.
First of all, I am a little bummed on Neuro. We had our first block exam on Wednesday. We were allowed to keep our written tests and a key was posted afterward, so I was able to check my score. I have myself down for an 86, which I am not thrilled about but can live with. I missed 9 out of 65 questions but I should have got at least three of those. However I am afraid I did much worse on the practical. They posted a key for that one too, but I can never remember what I answered well enough to check that one. I had spent a lot of time with the “brain buckets”. These are the specimens that were removed from our cadavers back in Gross. I think I did well on most of the questions that came from actual tissue specimens, but out of the almost 50 items on the practical, probably a third were photos of MRIs and stained slices. I guess I didn’t look at the atlas hard enough for the slices, because a lot of those photos looked like abstract art to me rather than portions of the human brain.
The really frustrating thing to me is that this is the course I really wanted to excel in. Neurology is really what brought me to medical school because of Manning’s problems. How will I ever help him if I don’t master this stuff? There are a ton of doctors out there who did better on this test than I did, and they haven’t been able to “fix” Manning. What makes me think I will be able to? Another disturbing trend – this is the third course we have had with a practical exam component to it. Without exception I perform much better on the written than on the practical. I am beginning to think I am lacking in observation skills and those are what physicians really need. It won’t do me much good if I have all the book learning in the world, but can’t recognize what I’m seeing on the patient.
Another thing keeping me busy this week was a visit from my mother who lives in New Mexico. She is a high school Spanish teacher there and was on spring break this week. I had not seen her since last summer. She usually visits more frequently, but had to have cataract surgery over her Christmas break and had to cancel travel plans. I tried to spend the time I wasn’t studying visiting with her, and that took my writing time away. Only so many hours in the day and all that!
We had a consult with a pediatric surgeon here in Jackson regarding Manning’s stomach reflux problems this week also. He ordered a 24 hour pH probe test. This involved a tube up Manning’s nose and into the pharynx where pH levels were measured on a portable device. Naturally he went the entire 24 hours without a reflux episode. He has in fact not had one in the last two-and-a-half days, so we are hoping that things are improving in that area. We haven’t heard what the results showed yet. Also the nurse from neurosurgery has told me that he has been tentatively put on the surgery schedule for the Vagus nerve stimulator device implant in June.
Thursday we had the highlight of the Physiology labs for the year. Most of these “lab” sessions are actually done on PCs and involve manipulating the treatment of a computer-generated patient. This one however was the much talked about and anticipated “dog lab.” The class is divided up into groups of 16 and the groups take turns over several weeks participating in the lab. It consists of doing some surgery on an anesthetized dog and then doing some experiments to learn about blood pressure and heart rate. We went into a small operating room in the Clinical Sciences building, and each sub-group of four students got their own dog. The animals had already been anesthetized and were tied down to the tables. These animals are older dogs that are on their last legs and are going to be put to sleep anyway. There are also vet techs on hand that monitor the anesthesia and insure the animals are being treated humanely. We made incisions in the groin to expose both femoral arteries. On one side we ran a catheter up into the left ventricle of the heart and on the other side placed on just a few inches into the femoral artery. These lines had transducers on them to monitor blood pressure. We also got a line in the femoral vein for drug injections. We then exposed the common carotid artery and vagus nerve on each side in the neck. Once we had completed our surgeries, the experiments begun. We observed the effects on heart rate and blood pressure for epinephrine, norepinephrine, acetylcholine, and angiotensin II. We had studied the effects of these neurotransmitters and hormones in class, but it sure does reinforce things in your mind when you see it happen before your eyes. We also temporarily occluded the carotids and then severed the vagus nerves to see what the response would be. After all of this we got down to the really cool stuff.
When our lab instructor, a research PhD asked who wanted to open the thorax I quickly volunteered for our group. I opened our poor hound dog up between the fourth and fifth ribs and after spreading the ribs open, we were able to observe the pretty pink lungs expanding and inflating with each breath. You might recall from my gross anatomy entries that for some reason that lung tissue fascinates me. Then we pulled the heart out from underneath and actually held the pumping mass in our hands. A very powerful feeling. The plan had been to induce a ventricular fibrillation with an electrical stimulus, but our dog spontaneously went into fibrillation. Who could blame it after all we had put it through? In fibrillation the heart has no rhythm and different regions are contracting spasmodically with no concert of effort. It has been describes as the “bag of worms” and that is exactly what it looked like, a little bag, jam-packed full of wriggling night crawlers. It was pretty wild. My lab partner, Alison got to use the defibrillation paddles to restore a normal rhythm and saved the dog’s life (albeit extremely temporarily.) Alison is a true warrior on this kind of stuff. She made all the rest of us look like sissies with our latex gloves on. She preferred the bare handed technique of surgical procedures and by the end of the lab had blood halfway up to her elbows on both arms. She has worked in research labs for the last couple of years and has plenty of experience with animals. Anybody who wanted could hang around and practice suturing, intubations and just about any other procedure they could think of. When we were through the animals were destroyed, but their last day was spent giving us a wonderful educational opportunity.