Ultrasound on the Go: From Stat Care to Visual 'Stethoscope'
Opening new doorsUltrasound scanning outside of the hospital setting isn’t new, but it is becoming more common, namely in emergency, military and disaster settings, says Robert J. Tillotson, DO, chairman and medical director of the emergency department at St. Michael’s Hospital in Stevens Point, Wis.
Tillotson recently returned from a trip to Peru where he took along a portable ultrasound system that he used to scan about 55 patients in four days at a temporary clinic. Describing the makeshift clinic set up on a cement slab, he says that he examined women for breech pregnancies, gall stones and fetal viability.
The Zonare z.one convertible ultrasound system, which he uses everyday at St. Michael’s and brought with him to Peru, lends itself to the scanning of patients with many disease states and in most clinical departments outside of the emergency department, including cardiac, gynecology and ocular. Teaching infrequent users how to scan also comes easily, too, due to the system’s auto-optimize button that produces a clear image without a lot of operator knowledge or training, notes Tillotson.
While the ultrasound system looks like a standard-sized scanner, the actual scanning machine is the size of a small laptop. “When I have to run to a code in the unit or go over to urgent care where I don’t want a big machine in the way, I can bring in [the system] in one hand and scan with the other,” he says.
Portable ultrasound devices have come a long way, Tillotson notes. The first hand-held scanners had poor image quality and small screens, he explains. Once laptop-sized equipment was developed, the hand-held capabilities were lost, but better image quality was gained.
The market has again opened up to handheld equipment, according to Tillotson, along with continually improved image quality. Portable ultrasound is allowing swifter, more-knowledgeable triage decision-making such as whether an accident victim should be rushed into surgery or have a CT scan first. This can potentially cut down the time it takes for patients to receive an imaging exam by hours and thus facilitate faster and hopefully better care, he says. The scanners allow for the evaluation of emergency medical conditions and diagnosis, resuscitation of acutely ill, critically ill or injured patients, guidance of high-risk or difficult procedures, monitoring of certain pathologic states and as an adjunct to therapy—all right at the bedside.
Despite the improvements made recently within ultrasound, Tillotson says that “emergency ultrasound is complimentary to the physical examination, but should be considered a separate entity that adds anatomic, functional and physiologic information to the care of the emergency patient.”
Size mattersLike Tillotson, Bruce Kimura, MD, of the department of cardiology at Scripps Mercy Hospital in San Diego, notes that there has been a decrease in size and an increase in portability in hand-carried ultrasound devices, particularly in the last two years. “They have gone from luggable laptop-size devices down to pocket-sized devices,” he says.
Kimura, who utilizes Siemens’ P10 portable ultrasound system, says that its ultraportability allows him to use it routinely during each patient encounter. He scans all patients for an initial evaluation. “That includes new patient consultations in both inpatient and outpatient settings, as well as established patients who develop new symptomology,” he says. He notes that the system is very useful in the screening of abdominal aortic aneurysms, plural diffusions, central venous pressure and renal asymmetry.
The amount of time it takes to employ the imaging portion of the examination is minimal, only an additional 10 to 15 minutes, says Kimura. “It doesn’t slow me down. I use the results to form my initial impression and guide my workup. I do not necessarily consider the results definitive so that they would need to be measured or recorded as a formal diagnostic test in the hospital record.”
There is a tradeoff, however, in terms of the capability of hand-carried ultrasound compared to a laptop-sized device, says Kimura, who notes that the laptop devices have more imaging features than the hand-carried or pocket-sized devices in terms of imaging quality and manipulation. “The portable devices don’t have all the bells and whistles that the laptops do,” he explains.
However, portable ultrasound systems have the potential to cut costs because they can reduce unnecessary consultations and diagnostic testing and potentially shorten hospital stays, Kimura says.
“These devices clearly improve patient care and offer a more accurate and effective initial diagnosis,” he says. “The major change in the morphology of the ultrasound [system] is that it now competes with the stethoscope as a use model.”
Workflow changesAnthony DeMaria, MD, a cardiologist at the University of California, San Diego Medical Center, who was among the first physicians in the country to evaluate the newest and smallest microportable scanner, the Vscan from GE, says its most important features are its small size—a cross between an iPod and a large flip phone—and portability, weighing just a pound and a half.
“It truly is small enough to fit into the pocket of my laboratory coat, which makes it convenient to carry around and have with me at all times,” he says. “To me, an important tipping point is when you can have an instrument with you all the time just as you have your stethoscope, and it can be quickly employed to examine a patient.” This would allow more information to be gathered during a physical examination.
In the cardiology department, the Vscan can be employed to solidify the physicians’ impressions of the exam. “If I am in the clinic and I hear a murmur, I can quickly use it for that application. If someone is short of breath, I can quickly evaluate left ventricular function,” he notes. “It’s a way of getting more information about cardiac structure and function that is more in depth, and more detailed than I could get from the physical exam, but I get [that additional information] in conjunction with the physical exam.”
Despite its advantages, DeMaria still says bigger is sometimes better for some exams. “[Portable ultrasound] can facilitate workflow in terms of making additional studies less necessary, but it does add more time to the overall exam of the patient,” he says. However, he does appreciate the fact that the device can quickly confirm any asymptomatic findings of a patient without the need of an echocardiogram.
Ultrasound in a new lightWhile portable ultrasound systems have been employed in both the cardiac and emergency department settings, DeMaria believes that the devices will soon be adopted by many more specialties. “I see this as the first step to bringing diagnostic ultrasound to the bedside, for not just cardiologists but to a whole range of physicians,” he says.
Both DeMaria and Kimura believe that portable ultrasound equipment should be thought of more as an extension of the physical examination, rather than a procedure to be included in the medical record.
“I use the results to form an initial impression and guide my workup, and I include the information in my consultation notes, but I do not necessarily consider the results definitive that they would need to be measured or recorded as a formal diagnostic test in the hospital record,” explains Kimura.
DeMaria agrees. “It’s a mindset, and it’s a hard mindset to adjust to for everybody who has been in the business and has used diagnostic ultrasound, and thinks of a standard imaging exam with hard copies and dictated report. In my opinion, [the device] is more like the stethoscope where it is incorporated into the overall physical examination.”