Point-of-care ultrasound (POCUS) of the chest should be used more widely in clinical practice as an adjunct to the stethoscope and possibly even replace it, according to physicians in New Zealand.
In a paper published in the Internal Medicine Journal they say portable ultrasound is essentially the modern technology version of the stethoscope for assessing heart and lung sounds, and in the hands of a skilled user can obtain more accurate and rapid diagnosis after taking as little as six minutes to complete the test.
Cardiologist Dr Peter McLeod and emergency medicine physician Dr Sierra Beck from Otago Medical School, say there is evidence to suggest that the diagnostic accuracy of the clinical exam, especially for detecting cardiac abnormalities and diagnosing pulmonary pathologies is limited.
But even in the hands of novice users, basic focussed cardiac ultrasound can be used to accurately identify cardiac abnormalities such as left ventricular dysfunction, they assert.
They highlight a 2005 study where two first year medical students without clinical experience used hand held ultrasound devices. After 18 hours of training the medical students identified significantly more of correct pathologies, (75%) than cardiologists performing clinical examination alone (49%).
Similar improvements in diagnostic performance (82% vs 47%) have been demonstrated when comparing cardiologists using hand-held ultrasound only with cardiologists performing physical examination alone in patients referred for routine outpatient transthoracic echocardiography, they note.
Hand-held ultrasound identified more patients with abnormal LV function (sensitivity 96% vs 35%), moderate to severe valve lesions (71% vs 31%) and abnormal RV function (68% vs 21%), than physical examination, though both were similarly poor at identifying patients with pulmonary hypertension (42% vs 53%).
The authors argue that hand-held ultrasound deserves to be used more widely by general physicians and practitioners, and after an initial learning curve the time to perform an examination can be reduced from 22 minutes to about six to ten minutes.
“POCUS can be seen as an evolution of the stethoscope, perhaps bringing clinicians back to the bedside and providing time to build a therapeutic relation,” they write.
“Once experience and expertise have been obtained, the clinical applications are numerous, with increasing evidence demonstrating exceptional diagnostic accuracy and shortened time to diagnosis. Learning POCUS will likely only strengthen a physician’s armamentarium for diagnosis, ongoing management and prognostication with less reliance, and possible delays, created by waiting for ancillary testing.
Although this may be the case, Dr Ben Kwan, Head of Department of Respiratory and Sleep Medicine, The Sutherland Hospital, Sydney, and lecturer at the University of New South Wales said that for many departments, POCUS replacing the stethoscope is just not practical. He suggested that the cost and proficiency are barriers to mandatory POCUS use, although emergency, critical care, respiratory departments, and private clinics could all benefit from having one available.
“I think on a day-to-day ambulatory clinical setting, it is unlikely at this stage POCUS will replace the stethoscope as alternative physical assessment tool,” he told the limbic.
“I certainly see POCUS at this stage to be complimentary to good history taking and physical examination (includes auscultation via stethoscope). I think ultrasound technology is certainly improving, and education of POCUS to clinicians is improving too – so perhaps in near future, POCUS for cardiac / respiratory / abdomin will be a lot more common.”