Monday, October 14, 2013
The Green Journal speaks out on Bedside Ultrasound
Today I found that there were two editorials on the use of handheld ultrasounds, specifically the Vscan, the little pocket model that I have used for the last nearly 2 years as a diagnostic tool at the bedside. One article, by Julie Kim MD and colleagues from Northwestern University in Chicago, IL presented the opinion that these devices should only be used as part of clinical trials or for evidence based indications. They based this view on a review of the literature which showed few prospective trials showing improved patient outcomes.
The following article, by Roy Ziegelstein, MD and David B. Hellmann, MD points out that "wise use of hand-carried ultasound may provide valuable information more quickly and less expensively, and thereby benefit both clinicians and patients." Furthermore, they point out that this "may enable clinicians to have a more active role in patient care, may facilitate patient education at the bedside, and may well restore joy and greater satisfaction to the life of health professionals." They do, however, agree with the first authors that before these devices are used by non-specialists in a widespread manner, there must be well conducted trials that demonstrate clinical benefits to patients.
When I first read the editorials I was frankly very irritated. Both the for and the against positions came out against actually doing routine bedside ultrasound as part of the physical exam. The specific argument was that bedside ultrasound would identify internal abnormalities which were not clinically significant, leading to overdiagnosis and over-testing and probably over-treatment. Dr. Kim et al pointed out that we know that screening for pancreatic cancer and ovarian cancer in patients without symptoms does not change the outcomes of these diseases, and that people with a little ultrasound in their pocket would not be able to resist finding these things. My experience with the Vscan is that it is a fine machine for looking for fluid in the wrong place and for examining the basic functions of the heart, and occasionally for examining abnormalities like tumors that more detailed imaging procedures or blatant symptoms had already pointed out, but that it is not at all easy to find an ovarian cancer or a pancreatic cancer with any degree of certainty, even if I look really hard, which I don't. The point that these authors completely miss is that we physicians are all using our physical exam skills to identify the diagnoses I look for with my little ultrasound, and we know that our physical exam skills have terrible sensitivity and specificity. We really can't tell if a person has heart failure or fluid overload or ascites (fluid in the belly) or pleural effusions (fluid around the lungs) which are vital to giving appropriate treatments. We are taught how to detect these things with our hands and ears and stethoscopes, but good studies show that, even if we are skillful and attentive, we are not much better than chance at identifying these things with any degree of certainty. Nevertheless we continue to use our physical exam skills to make these diagnoses and treat or test the patient based on educated guesses. Ultrasound, even performed inexpertly, is better than this.
I stepped back a bit from my desire to scream and thought about the issues these authors brought up. Yes, there is a potential for overdiagnosing various conditions of little or no clinical significance or finding diseases that no amount of early treatment can cure. We are going to need to figure out what to do with our new level of confidence in our diagnostic abilities. We will need to figure out how to define competence in this new technology so we don't find ourselves becoming convinced by blurry images of findings that aren't real. But there are many physicians who employ bedside ultrasound successfully and already use their pocket ultrasounds to "have a more active role in patient care and facilitate patient education at the bedside" and are even now restoring joy and satisfaction to their calling. These doctors are not involved in clinical trials, at least not most of them, but are on the forefront of discovering what this technology is really good for. Many medical schools consider performing and interpreting ultrasound at the bedside to be a core competency, and medical students are trained to make it part of their practice. Dr. David Tierney directs IMBUS (Internal Medicine Bedside Ultrasound program) at Abbott Northwest Hospital, the largest hospital in Minnesota's twin cities, which teaches all of the medical residents to be competent to use bedside ultrasound. This program combines extensive practice with wireless communication and frequent conferences to share expertise and produces internists who will most likely seamlessly incorporate ultrasound into whatever patient care field they eventually pursue. Like the stethoscope or the computer, bedside ultrasound, and pocket devices that make it more convenient, have already transformed medical practice, and now the most interesting question is not "should we?" but "how do we?"
It was gratifying that a journal that is one of the standards of Internal Medicine is addressing the issue of handheld ultrasound. It is a little disappointing that the doctors giving their opinions don't seem to actually do bedside ultrasound, which would make their opinions a bit more significant.