I spent last week learning the fundamentals of using ultrasound in the bedside evaluation of the patient in the emergency department. The use of this technology expands the three senses I routinely employ when I examine patients.
In the traditional physical examination the doctor looks at the patient, uses a stethoscope to listen to sounds made by the organs, and feels with his or her hands to discover anatomic abnormalities. Ultrasound has the most profound effect on the visual examination, as it permits the physician to look inside the body. No longer dependent on the reflection of visible light from the patient to the examiner's eye, the doctor can "shine" the ultrasound beam into the body from the surface and see (on a monitor) the images produced by the reflection.
When ultrasound is used to examine the heart and blood vessels, it is possible both to see and to hear blood flow. And this technology enables the physician to combine seeing and feeling in ways otherwise impossible. When I see a patient with pain in the upper abdomen on the right side, I may press where I think the gall bladder is to see if that hurts. With ultrasound, I can see the gall bladder when I'm pressing, so I not only know whether the gall bladder looks diseased, I can also tell directly whether it is tender to touch - important because that helps to confirm that it is the diseased gall bladder that is causing the patient's pain. Similarly, when I see a woman with pelvic pain, I can not only see that she has ovarian cysts (which are very common and usually asymptomatic) but can also tell whether they are tender to touch, and thus likely (or not) to be the source of her pain.
[For those curious about the other two senses, I'll just say there are many things the astute clinician can discern about patients by smell, but nowadays we don't really employ taste. I can only imagine how that would be regarded by a disciplinary review board.]
We now use ultrasound to examine the body quite literally from head to toe. Ultrasound can reveal important findings of injury to and disease of the eye, and it can be used to find fluid in the joint of a toe and facilitate withdrawing some of that fluid through a needle to send to the laboratory and confirm the diagnosis of gout. We may use it to help us see a large vein in the neck as we place an intravenous line there, or we may evaluate blood flow to the brain through the carotid arteries. We can also examine blood flow through the arteries and veins in the arms and legs. There are many things we can find out by employing ultrasound to evaluate organs in the chest, abdomen, and pelvis, from structure and function of the heart, to diseases of the liver and kidneys, to whether a pregnancy is in the uterus (where it belongs) or in one of the Fallopian tubes (where it may rupture and kill a young woman).
Perhaps the most exciting use of ultrasound is in the rapid detection, in an injured patient, of internal bleeding in the chest, abdomen, or pelvis. This can tell us right away that a patient must go directly from the emergency department's trauma bay to the operating room (do not pass go, do not collect $200) because of major bleeding. Rapid decision making is critical in such a situation, because minutes can, quite literally, mean the difference between life and death.
When I was in training in the mid-80s, there was no such thing as the use of bedside ultrasound in the ED. The first paper about the use of ultrasound in emergency medicine was published in 1988. The American College of Emergency Physicians (ACEP) offered its first course dedicated to the subject in 1990. The Society for Academic Emergency Medicine developed a model curriculum for training emergency physicians to use ultrasound and published it in 1994. ACEP's Ultrasound Section has done a great deal of extraordinary work, including the development of ACEP's emergency ultrasound guidelines, first published in 2001 and revised in 2008.
Many emergency departments, including most of the ones where I've practiced over the years, still do not have ultrasound capability, because the ED does not have an ultrasound machine or the doctors aren't trained to use one (or both). But last summer I joined the staff at an academic medical center, and not only must I know how to do this, but I must acquire mastery sufficient to teach the next generation. So I have just taken the first step on the path to that mastery.
The path is long. If you want to be a technologist ("ultrasonographer"), that takes two years. The training program is also two years for echocardiographers, those who use ultrasound strictly for imaging the heart. Of course physicians learning ultrasound have a big initial advantage, because we already know the anatomy and physiology of everything we want to examine. On the other hand, ultrasound is only a relatively small part of our practice, because we don't use it on everybody, and so that greatly lengthens the learning curve.
Forty hours of highly intensive instruction was a good start, though. If you have occasion to see me as a patient, expect me to try to come up with a reason to examine some part of you with ultrasound. But don't worry. It doesn't hurt, it has no known adverse effects, and because I'm learning, there will be no charge. And I might just find something important, or at least be able to tell you the bad thing we worried about is not there. After more than a quarter century in practice, I am doing something that will make me a better doctor. Yes, I am excited.
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