Wednesday, April 17, 2013
How to learn bedside (point of care) ultrasound: tips for the interested internist
Emergency physicians have embraced the use of ultrasound at the bedside for many years and the vast majority of physicians who complete emergency medicine residencies are competent in using ultrasound for procedures and diagnosis. In bedside ultrasound, the doctor who examines the patient also does the ultrasound, often with a small portable machine, checking out the heart, lungs and other internal organs as part of the physical exam. Internal medicine physicians have been very slow to pick up this technology, probably mostly because the equipment has been a little too large to be convenient and training to wield the probe and interpret the images takes time and is inaccessible. The American Academy of Chest Physicians (ACCP) is the professional organization that represents critical care and pulmonary doctors, and their journal, Chest, has recently adopted ultrasound education via an online section called the Ultrasound Corner. The editorial by Seth Koenig MD accurately describes the power of the technique in critically ill patients, and the educational offerings of the ACCP for intensivists.
So, first of all, why might an internist want to learn bedside ultrasound and how might it be merged effortlessly into patient care? When I see a patient now, instead of taking their pulse and placing my stethoscope on their chest and back, hearing the vague taps and clunks and bubbles and whooshes of the internal organs I have come to trust are in there, I open the ultrasound machine that lives in my white coat, squeeze a little gel from a tube I keep warm in my pocket, and the patient and I look at heart, lungs, liver, spleen, kidneys and bladder. Most of them, those not blind or in a coma, think this is incredibly cool. At the end of this exam, which takes all of 5 minutes if I am thorough, I know whether their heart squeezes normally, whether there is excess fluid in the lungs or pericardial sack, whether there is fluid in the belly, whether the kidneys are blocked and whether the bladder is emptying normally. Sometimes I also see things like gallstones or tumors or blood clots. I can often evaluate whether the patient is dehydrated by looking at the inferior vena cava, the vein that returns blood from the lower body to the heart.
If a patient loses consciousness, like one of them just did today, I can quickly rule out a major heart attack as the cause of the problem. My little machine is not quite as sensitive as the huge expensive ultrasound machines, but it is pretty good and I can usually be sure about the answers to the questions that are most vital to treating my patients immediately. If a patient has chest pain and my ultrasound of their heart is good, I can be much more confident about whether the chest pain is due to a heart attack. Several times since I have been doing this, I have found an unexpectedly poorly functioning heart in a patient whose story of chest pain was not particularly convincing for coronary artery disease and was able to advocate for quick or aggressive treatment which expedited treatment and saved heart muscle. The ability to evaluate bladder size is powerful. The ability to rule out hydronephrosis (urine backed up in the kidneys) allows me to avoid excessive imaging in patients who have a change in their kidney function. We often see patients with big bellies who may or may not have excess fluid due to cancer or liver failure or heart failure, and it is so very convenient to be able to make the distinction between fat and fluid without waiting for an imaging procedure to be done.
But how does a person learn how? I took 3 emergency ultrasound CME classes with live models and hands on instruction, one on line ACCP class in critical care ultrasound and bought the pocket Vscan ultrasound from GE which I use at least once on just about every patient, friend and family member. The dog has barely escaped due to excess fur. I then took a mini ultrasound fellowship with the department of emergency ultrasound at UC Irvine under the direction of Chris Fox MD. This involved 4 weeks of scanning in the ER, going over saved scans, teaching medical students and studying online material. It was kind of expensive: $5000 for the fellowship and 4 weeks off of work in a place where I had to stay at a hotel. But I am way better at it than I was, I know what the protocols are and can do ultrasound of things that internists don't usually examine that way, including eyeballs and uteruses and testicles and thyroids and skin structures. My Vscan doesn't have a linear transducer, so I haven't been able to improve as fast at procedures that need shallow scanning, such as blood vessels, muscles and joints. I'm thinking that I will need to have access to a machine that I can use whenever I want, so I will probably buy an ultrasound machine with a linear transducer from China where the technology costs about 1/10th what it does here.
There are other ways to learn bedside ultrasound, including year long fellowships, which are usually based in emergency rooms. There is a program at Harvard that lasts 5 or 10 days that involves participating in scanning at the radiology department, and reviewing many scans every day. I would love to do that. The limitation of learning ultrasound techniques from real ultrasonographers and radiologists is that they do a more thorough exam than we usually have time for, and the perfect protocol for quickly determining relevant information in an internal medicine patient is not the same as what an ultrasonographer does when we order specific tests. The ACCP has excellent courses with live patient scanning, which are apparently quite expensive. I would also love to take one of these. There are many for-profit groups that offer training as well. It's not hard to find a course that will get a person started, but it does take many hours of practice and the ability to review scans with experts in order to feel comfortable. If our hospitals or clinics decided to embrace bedside ultrasound, and radiologists bought into it (and I actually think they would) we could really benefit from the teaching of our radiology technicians and MD radiologists.
It continues to astonish me how much more effective I am as a doctor with an ultrasound than I was as a doctor without one. I make diagnoses I wouldn't have thought of, save patients radiation and hospital days and quickly have information I need to focus treatment. I understand why my busy colleagues haven't embraced this technology yet, but when they do they are going to love it!