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| PennInTouch with a slightly depressingly- far-away graduation date. |
Hi
everyone! My name is Jessica, and I’m a first year MD-PhD student. I’m from
Centreville, Virginia, which is about 20 minutes outside D.C. I did my
undergrad at MIT, where I majored in bioengineering and minored in music, and
just graduated in June 2012. I’m interested in a bunch of things, both on the
research (tissue engineering, microfluidics, computational biology…) and
medical (peds, cardiology, neurology…) sides, so I’m not quite (read: not at
all) sure what I “want to do” yet, but my expected graduation date is
apparently Spring 2020—see screen capture from PennInTouch—so I guess I still
have plenty of time to figure it out. This is also my
first blog post, so I’m kind of nervous, but here goes:
You
may have heard that Penn has something called VC2000, which is like Reunion
Hall CSPAN (Reunion Hall is where we have lecture). All of our lectures are
recorded and put on VC, so that those who can't attend a lecture in person
can watch them from home later. It’s pretty popular!
Anyway,
I took advantage of VC recently too, but not to sleep in (although some do); instead, I shadowed at
HUP’s electrophysiology lab! It was amazing. The backstory is that we have a
project for our Mod 6 Doctoring class called ITAP (Interprofessional Team
Assessment Project), where we’re supposed to observe a medical team in action
and analyze how they work together. So Thursday morning, Russell (who is on my
learning team) and I went up to the 9th floor of Founders in HUP to
watch the electrophysiology team do their daily morning meeting. We watched how
the team members interacted as they discussed the patients they’d be seeing
that day, determined what procedures they’d be doing, and made some decisions as to how
certain patients should be cared for. After we’d fulfilled the bulk of our ITAP
responsibilities, we stuck around to talk to/do some short interviews with some
of the team members (also for ITAP), and of course, to watch the procedures.
First,
I went to see an ICD replacement, while Russell headed off to watch an atrial
flutter ablation. ICDs (Implantable Cardioversion Defibrillators) are about
half-cell-phone-sized, battery-powered generators that use electricity to
effectively shock the heart back into normal rhythm when the patient has dangerous
irregular heartbeats. Here’s a Youtube video of one in action:
And here's the corresponding article in Sports Illustrated: http://sportsillustrated.cnn.com/vault/article/magazine/MAG1165292/index.htm.
ICDs have a limited lifespan, though, so they need to be replaced every so
often. The procedure for replacement was very different from what I expected—only a local
anesthetic is used, the incision to take out the old ICD and put in the new one
is just a few inches long, and the entire process took about half an hour. Only
the generator—not the wires that connect it to the heart—get replaced, and a lot of double- and triple- and quadruple-checking goes on to make sure the wires are reconnected correctly. I didn’t
understand much, and it didn’t seem like a good time to interrupt with a
million questions, but it looked and sounded like each wire is color-coded, labeled
with what part of the heart it’s coming from, and labeled with a serial number
to make sure that it connects to the right place in the generator. The patient
was actually awake until the very end, when the electrophysiologists induced an irregular rhythm in order to test the new device.
Since
the ICD replacement went so smoothly and quickly, I went to find Russell, who
was watching an atrial flutter ablation, after it was done. The setup for the
atrial flutter ablation reminded me of an airport control tower. Since the ablation done by inserting a catheter into the femoral vein and
guiding it up into the heart, X-rays are used for imaging throughout the
process. In order to minimize X-ray exposure for the doctors who are doing
these procedures every day, one of them is in the room with the patient
doing the ablation while another one is in a “control room,” watching and
guiding. Everyone inside the procedure room is wearing lead jackets to
protect themselves from the X-rays, and the control and procedure rooms communicate via headset.
On every monitor in the control room, a large number of indecipherable squiggles were running across the screen. Luckily for us though, it
turns out the ablation procedure includes a 30-minute wait, so during the
waiting period the attending paused to explain these squiggles, and what on earth an atrial flutter
ablation is anyway.
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| Image adapted from the National Heart, Lung and Blood Institute. Original image here: http://www.nhlbi.nih.gov/health//dci/ Diseases/holes/holes_types.html |
Heart
muscles contract when they are stimulated by electricity, which is made in some
special heart cells and is sent throughout the muscles. Normally, the
electrical current passes through the atria in the upper part of the heart once, causing them to contract
and pump blood into the ventricles, which then pump blood into the body. However, in atrial flutter, the electricity
keeps on going around and around the atrium instead of
disappearing. As a result, even though the atria contract more often, each
contraction is less efficient, and this can cause all sorts of problems,
including blood clots. To fix the problem, electrophysiologists can make a series of
tiny burns in the wall of the atrium; this is called ablation. Then in the
future, if the current tries to go around the atrium instead of
stopping like it should, the electricity will get stuck where the burns were placed, and the
atria will continue to contract normally.
When
the half-hour wait was over, it was time to see whether the ablation had
worked. To do this, the doctors stimulated the heart muscle with electricity in
one location, and then measured how long it took to get to two other places in the
atria. Based on which of these two places “felt” the electricity first, they
could tell whether current was still passing through the area they had
intended to ablate. To give an idea of the level of precision involved, they were
looking at differences on the order of tens of milliseconds—for comparison, test
your reaction time here: http://www.humanbenchmark.com/tests/reactiontime/ (average appears to be ~215ms. Guess I'm way below average!). Fortunately, the equipment being used could detect time differences that are much shorter than human reaction times, and they saw the stimulation pattern they expected, which meant that the procedure had
worked.
After watching the ablation, we decided it was time to end our brief foray into real life after med school, and headed back to the biomed library to catch up on some rheumatology lectures. Shadowing
was great, though; and we learned so much! I loved shadowing in the EP lab, but for those who aren’t as
interested in cardiology, Penn also has many other shadowing opportunities,
both at HUP and at CHOP—in fact, shadowing in the emergency departments at both
hospitals is an established "thing" and is fairly common among our classmates. Some people also just set up
shadowing times outside of the emergency departments, with small group preceptors, for example. Whatever your interests, shadowing opportunities are fairly easy to come by here, and definitely worth missing lecture for once in a while!
