The diagnostic accuracy of pocket-size cardiac ultrasound performed by unselected residents with minimal training

Clinical comparison of a handheld cardiac ultrasound device for the assessment of left ventricular function

PURPOSE

Recently developed handheld ultrasound devices (HHUD) represent a promising method to evaluate the cardiovascular abnormalities at the point of care. However, this technology has not been rigorously evaluated. The aim of this study was to explore the correlation and the agreement between the LVEF (Left Ventricular Ejection Fraction) visually assessed by a moderately experienced sonographer using an HHUD compared to the routine LVEF assessment performed at the Echocardiography Laboratory.

METHODS

This was a prospective single center study which enrolled 120 adult inpatients and outpatients referred for a comprehensive Echocardiography (EC).

RESULTS

The mean age of the patients was 69.9 ± 12.5 years. There were 47 females (39.2%). The R-squared was r 0.94 (p < 0.0001) and the ICC was 0.93 (IC 95% 0.91-0.95, p ≤ 0.0001). The Bland-Altman plot showed limits of agreement (LOA): Upper LOA 10.61 and Lower LOA - 8.95. The overall agreement on the LVEF assessment when it was stratified as "normal" or "reduced" was 89.1%, with a kappa of 0.77 (p < 0.0001). When the LVEF was classified as "normal", "mildly reduced", "moderately reduced", or "severely reduced," the kappa was 0.77 (p < 0.0001). The kappa between the HHUD EC and the comprehensive EC for the detection of RWMAs in the territories supplied by the LAD, LCX and RCA was 0.85, 0.73 and 0.85, respectively.

CONCLUSION

With current HHUD, an averagely experienced operator can accurately bedside visual estimate the LVEF. This may facilitate the incorporation of this technology in daily clinical practice improving the management of patients.

The Point-of-Care Ultrasound (POCUS) by the Handheld Ultrasound Devices (HUDs) in the COVID-19 Scenario: a Review of the Literature

The use of portable ultrasound (US) devices is increasing, due to its accessibility, versatility, non-invasiveness, and its significant support in the patient management, extending the traditional physical examination through the POCUS (point-of-care ultrasound). The pocket-size or handheld ultrasound devices (HUDs) can easily perform focused exams, not aiming to substitute for the high-end US systems (gold standard), since the HUDs usually have more limited functions. The HUDs are promising tools for the diagnosis, prognosis, and monitoring of the COVID-19 infection and its related disorders. In conclusion, the routine use of HUDs may ameliorate the management of COVID-19 pandemic, according to the guidelines for the POCUS approach and the procedures for the protection of the patients and the professionals.

Echoscopy in scanning cardiac diseases in critical care medicine

BACKGROUND AND AIMS

Targeted ultrasound examinations with a portable ultrasound device ("handheld ultrasound system"; HHUS) have been defined as "echoscopy" by the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB). Cardiac scanning with HHUS is feasible. Echoscopy could play a major role in emergency and intensive care medicine, but adequate data on its effectiveness are still lacking. Sonographic examinations in the field of emergency and intensive care medicine can often not be carried out under standardized examination conditions. Thus, the aim of this study is to show that the use of HHUS for echocardiography in emergency medicine is possible and that for this setting HHUS is not inferior to a high-end ultrasound system (HEUS) for detecting cardiac pathologies.

METHODS

The examinations were carried out with a Vscan™ (GE Medical Systems, Solingen, Germany) and a high-end ultrasound device (Acuson X‑300 or X‑700). The examinations were randomized and blinded to two examiners within 30 min. The examinations took place in the intensive care unit, the emergency room and the ambulance service. The results were recorded in an examination sheet.

RESULTS

In all, 93 patients (61 men and 32 women, age 69 ± 14.76 [33-95] years). In 32.6% (30/93) of examinations with HEUS the examination conditions were optimal and in 29.03% (27/93) when the HHUS was used. Of the examinations, 50.08% (31/61) were carried out by both examiners in the same patient position. Using HHUS, the following sensitivity and specificities (respectively) were found: pericardial effusion (73.68%; 96.97%), hemodynamically relevant effusion (50%; 97.67%), right heart strain (90,91%; 96,72%), arrest of the right ventricle (100%; 87,5%), limitation of left ventricular pump function (91.49%; 86.11%), wall movement disorders (WMD, 97.29%; 78.95%), aortic valve sclerosis (42.86%; 86.67%), aortic regurgitation (60%; 95%), mitral valve sclerosis (60%; 100%), mitral reguritation (66.67%; 82.86%), tricuspid valve regurgitation (48%; 81,48%). Measurements of the dimensions of pericardial effusion, the left ventricle, the left atrium and the left ventricular posterior wall each had a positive correlation between the examination with HHUS and HEUS (Κ = 0.45 to 0.91). The diameters determined by HHUS and HEUS for the septum and aortic root, however, correlated negatively (κ = -0.61 to -0.86).

CONCLUSIONS

The use of echoscopy in emergency and intensive care medicine is not inferior to HEUS for detecting defined cardiac pathologies.

Focal cardiac ultrasound learning with pocked ultrasound device: A bicentric prospective blinded randomized study

PURPOSE

Point-of-care ultrasound using a pocket-ultrasound-device (PUD) is increasing in clinical medicine but the optimal way to teach focused cardiac ultrasound is not clear. We evaluated whether teaching using a PUD or a conventional-ultrasound-device (CUD) is different when the final exam was conducted on a PUD. The primary aim was to compare the weighted total quality scale (WTQS, out of 100) obtained by participants in the two groups (CUD and PUD) on a live volunteer 2-4 weeks after their initial training. The secondary aims were to compare examination time and students' confidence levels (out of 50).

METHODS

This bicentric, prospective single-blind randomized trial included undergraduate medical students. After watching a 15 min video about echocardiography views, students had a 45 min hands-on training session with a live volunteer using a PUD or a CUD. The final examination was conducted with a PUD on a live volunteer.

RESULTS

Eighty-six comparable students were included, with 4 ± 1 years of medical training. In the PUD group, the mean WTQS was 65 ± 16 versus 60 ± 15 in the CUD group [p = 0.22; in multivariate analysis, OR 0.8 95% CI (0.1;1.6), p = 0.34]. The examination time was 10.0 [6.2-12.4] min in the PUD group versus 11.4 [7.3-13.2] in the CUD group (p = 0.39), while the confidence level was 27.9 ± 7.7 in the PUD group versus 27.4 ± 7.2 in the CUD group (p = 0.76).

CONCLUSION

There was no difference between teaching echocardiographic views using a PUD as compared to a CUD on the PUD image quality, exam time, or confidence level of students.

Diagnostic accuracy of handheld cardiac ultrasound device for assessment of left ventricular structure and function: systematic review and meta-analysis

Objective

Handheld ultrasound devices (HUD) has diagnostic value in the assessment of patients with suspected left ventricular (LV) dysfunction. This meta-analysis evaluates the diagnostic ability of HUD compared with transthoracic echocardiography (TTE) and assesses the importance of operator experience.

Methods

MEDLINE and EMBASE databases were searched in October 2020. Diagnostic studies using HUD and TTE imaging to determine LV dysfunction were included. Pooled sensitivities and specificities, and summary receiver operating characteristic curves were used to determine the diagnostic ability of HUD and evaluate the impact of operator experience on test accuracy.

Results

Thirty-three studies with 6062 participants were included in the meta-analysis. Experienced operators could predict reduced LV ejection fraction (LVEF), wall motion abnormality (WMA), LV dilatation and LV hypertrophy with pooled sensitivities of 88%, 85%, 89% and 85%, respectively, and pooled specificities of 96%, 95%, 98% and 91%, respectively. Non-experienced operators are able to detect cardiac abnormalities with reasonable sensitivity and specificity. There was a significant difference in the diagnostic accuracy between experienced and inexperienced users in LV dilatation, LVEF (moderate/severe) and WMA. The diagnostic OR for LVEF (moderate/severe), LV dilatation and WMA in an experienced hand was 276 (95% CI 58 to 1320), 225 (95% CI 87 to 578) and 90 (95% CI 31 to 265), respectively, compared with 41 (95% CI 18 to 94), 45 (95% CI 16 to 123) and 28 (95% CI 20 to 41), respectively, for inexperienced users.

Conclusion

This meta-analysis is the first to establish HUD as a powerful modality for predicting LV size and function. Experienced operators are able to accurately diagnose cardiac disease using HUD. A cautious, supervised approach should be implemented when imaging is performed by inexperienced users. This study provides a strong rationale for considering HUD as an auxiliary tool to physical examination in secondary care, to aid clinical decision making when considering referral for TTE.

Trial registration number

CRD42020182429.

Cardiovascular examination using hand-held cardiac ultrasound

Echocardiography is the first-line imaging modality for assessing cardiac function and morphology. The miniaturisation of ultrasound technology has led to the development of hand-held cardiac ultrasound (HCU) devices. The increasing sophistication of available HCU devices enables clinicians to more comprehensively examine patients at the bedside. HCU can augment clinical exam findings by offering a rapid screening assessment of cardiac dysfunction in both the Emergency Department and in cardiology clinics. Possible implications of implementing HCU into clinical practice are discussed in this review paper.

Screening for aortic stenosis using physical examination and echocardiography

Most patients with aortic stenosis (AS) can be treated with either traditional surgical aortic valve replacement or newly emerged transcatheter aortic valve implantation. Therefore, the early and appropriate detection of significant AS has become more important for avoiding overlooking patients who require treatment. AS is initially detected by the presence of a systolic ejection murmur (SEM). However, it is time-consuming and expensive for all subjects presenting with SEM to undergo comprehensive standard echocardiography using high-end ultrasound machines since the SEM is audible in a large proportion of elderly patients and is not specific for significant AS. Therefore, further physical examination and/or focused cardiac ultrasound (FoCUS) is required to determine whether patients with a SEM should be referred for standard echocardiography. One or more abnormal physical findings in addition to a SEM can rule out a certain proportion of normal cases without overlooking severe AS. Most of the previous studies suggesting the usefulness of FoCUS in screening for valvular heart disease only used visual impressions in their assessment of AS. By contrast, visual AS and calcification scores are good objective parameters in screening for AS with FoCUS. Patients with severe AS and patients with a high probability of AS-related events are rarely overlooked even if comprehensive standard echocardiography is performed only when either (or both) of the FoCUS scores is 3 or more. The appropriate combination of physical examinations and FoCUS to screen for AS is discussed in this review article.

Ensuring competency in focused cardiac ultrasound: a systematic review of training programs

BACKGROUND

Focused cardiac ultrasound (FoCUS) is a valuable skill for rapid assessment of cardiac function and volume status. Despite recent widespread adoption among physicians, there is limited data on the optimal training methods for teaching FoCUS and metrics for determining competency. We conducted a systematic review to gain insight on the optimal training strategies, including type and duration, that would allow physicians to achieve basic competency in FoCUS.

METHODS

Embase, PubMed, and Cochrane Library databases were searched from inception to June 2020. Included studies described standardized training programs for at least 5 medical students or physicians on adult FoCUS, followed by an assessment of competency relative to an expert. Data were extracted, and bias was assessed for each study.

RESULTS

Data were extracted from 23 studies on 292 learners. Existing FoCUS training programs remain varied in duration and type of training. Learners achieved near perfect agreement (κ > 0.8) with expert echocardiographers on detecting left ventricular systolic dysfunction and pericardial effusion with 6 h each of didactics and hands-on training. Substantial agreement (κ > 0.6) on could be achieved in half this time.

CONCLUSION

A short training program will allow most learners to achieve competency in detecting left ventricular systolic dysfunction and pericardial effusion by FoCUS. Additional training is necessary to ensure skill retention, improve efficiency in image acquisition, and detect other pathologies.

ESR statement on portable ultrasound devices

The use of portable ultrasound (US) devices has increased in recent years and the market has been flourishing. Portable US devices can be subdivided into three groups: laptop-associated devices, hand-carried US, and handheld US devices. Almost all companies we investigated offer at least one portable US device. Portable US can also be associated with the use of different US techniques such as colour Doppler US and pulse wave (PW)-Doppler. Laptop systems will also be available with contrast-enhanced US and high-end cardiac functionality.

Portable US devices are effective in the hands of experienced examiners. Imaging quality is predictably inferior to so-called high-end devices.

The present paper is focused on portable US devices and clinical applications describing their possible use in different organs and clinical settings, keeping in mind that patient safety must never be compromised. Hence, portable devices must undergo the same decontamination assessment and protocols as the standard equipment, especially smartphones and tablets.

Hand-held cardiac ultrasound examinations performed in primary care patients by nonexperts to identify reduced ejection fraction

BACKGROUND

Early identification of patients with reduced left ventricular ejection fraction (LVEF) could facilitate the care of patients with suspected heart failure (HF). We examined if (1) focused cardiac ultrasound (FCU) performed with a hand-held device (Vscan 1.2) could identify patients with LVEF < 50%, and (2) the distribution of HF types among patients with suspected HF seen at primary care clinics.

METHODS

FCU performed by general practitioners (GPs)/GP registrars after a training programme comprising 20 supervised FCU examinations were compared with the corresponding results from conventional cardiac ultrasound by specialists. The agreement between groups of estimated LVEF < 50%, after visual assessment of global left ventricular function, was compared. Types of HF were determined according to the outcomes from the reference examinations and serum levels of natriuretic peptides (NT-proBNP).

RESULTS

One hundred patients were examined by FCU that was performed by 1-4 independent examiners as well as by the reference method, contributing to 140 examinations (false positive rate, 19.0%; false negative rate, 52.6%; sensitivity, 47.4% [95% confidence interval [CI]: 27.3-68.3]; specificity, 81.0% [95% CI: 73.1-87.0]; Cohen's κ measure for agreement = 0.22 [95% CI: 0.03-0.40]). Among patients with false negative examinations, 1/7 had HF with LVEF < 40%, while the others had HF with LVEF 40-49% or did not meet the full criteria for HF. In patients with NT-proBNP > 125 ng/L and fulfilling the criteria for HF (68/94), HF with preserved LVEF (≥50%) predominated, followed by mid-range (40-49%) or reduced LVEF (< 40%) HF types (53.2, 11.7 and 7.4%, respectively).

CONCLUSIONS

There was poor agreement between expert examiners using standard ultrasound equipment and non-experts using a handheld ultrasound device to identify patients with reduced LVEF. Asides from possible shortcomings of the training programme, the poor performance of non-experts could be explained by their limited experience in identifying left ventricular dysfunction because of the low percentage of patients with HF and reduced ejection fraction seen in the primary care setting.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov (NCT02939157). Registered 19 October 2016.

The use of handheld ultrasound devices: a position statement of the European Association of Cardiovascular Imaging (2018 update)

Recent technological advances in echocardiography, with progressive miniaturization of ultrasound machines, have led to the development of handheld ultrasound devices (HUD). These devices, no larger than some mobile phones, can be used to perform partial, focused exams as an extension to the physical examination. The European Association of Cardiovascular Imaging (EACVI) acknowledges that the dissemination of appropriate HUD use is inevitable and desirable, because of its potential impact on patient management. However, as a scientific society of cardiac imaging, our role is to provide guidance in order to optimize patient benefit and minimize drawbacks from inappropriate use of this technology. This document provides updated recommendations for the use of HUD, including nomenclature, appropriateness, indications, operators, clinical environments, data management and storage, educational needs, and training of potential users. It also addresses gaps in evidence, controversial issues, and future technological developments.

A systematic review of pocket-sized imaging devices: small and mighty?

Introduction

Hand-held imaging devices are widely used in clinical practice and are a useful tool. There is no published review examining the diagnostic parameters achieved with these devices in clinical practice.

Methods

We searched three online medical literature databases (PubMed, EMBASE and MEDLINE) for all literature published up until January 2018. We selected studies that (1) were conducted in the adult population; (2) used a truly hand-held device; (3) featured sensitivities and/or specificities on the use of the hand-held scanner. We extracted and summarised the diagnostic metrics from the literature.

Results

Twenty-seven articles were excluded from the initial 56 relevant articles, as the device featured was not truly hand-held. Ultimately a total of 25 studies were analysed. Sixteen studies were carried out by experienced users, seven by users with little previous experience and two studies by nurses. High diagnostic parameters were achieved by all three groups when scanning cardiac pathology and intra-abdominal structures. Training of non-expert users varied, taking a mean of 21.6 h. These hand-held devices can change diagnoses at the bedside and be used as gate-keepers to formal echocardiography. Individual studies show them to be cost-effective.

Conclusion

Hand-held echocardiography is a useful tool in the hands of experts and novices alike. Studies conducted are highly heterogeneous making it difficult to pool data for the diagnostic metrics. Further studies with rigorous methodology are needed to evaluate the true diagnostic potential in the hands of non-experts and in the community as well as to validate training protocols.

Brief cardiovascular imaging with pocket-size ultrasound devices improves the accuracy of the initial assessment of suspected pulmonary embolism

Pulmonary embolism onset is frequently neglected due to the non-specific character of its symptoms. Pocket-size imaging devices (PSID) present an opportunity to implement imaging diagnostics into conventional physical examination. The aim of this study was to test the hypothesis that supplementation of the initial bedside assessment of patients with suspected pulmonary embolism (PE) with four-point compression venous ultrasonography (CUS) and right ventricular size assessment with the use of PSID equipped with dual probe could positively influence the accuracy of clinical predictions. A single-centre, prospective analysis was conducted on 100 patients (47 men, mean age 68 ± 13 years) with suspected PE. Clinical assessment on the basis of Wells and revised Geneva score and physical examination were supplemented with CUS and RV measurements by PSID. The mean time of PSID scanning was 4.9 ± 0.8 min and was universally accepted by the patients. Fifteen patients had deep venous thrombosis and RV enlargement was observed in 59 patients. PE was confirmed in 24 patients. If the both CUS was positive and RV enlarged, the specificity was 100% and sensitivity 54%, ROC AUC 0.771 [95% CI 0.68-0.85]. The Wells rule within our study population had the specificity of 86% and sensitivity of 67%, ROC AUC 0.776 (95% CI 0.681-0.853, p < 0.0001). Similar values calculated for the revised Geneva score were as follows: specificity 58% and sensitivity 63%, ROC AUC 0.664 (95% CI 0.563-0.756, p = 0.0104). Supplementing the revised Geneva score with additional criteria of CUS result and RV measurement resulted in significant improvement of diagnostic accuracy. The difference between ROC AUCs was 0.199 (95% Cl 0.0893-0.308, p = 0.0004). Similar modification of Wells score increased ROC AUC by 0.133 (95% CI 0.0443-0.223, p = 0.0034). Despite the well-acknowledged role of the PE clinical risk assessment scores the diagnostic process may benefit from the addition of basic bedside ultrasonographic techniques.

A urologic stethoscope? Urologist performed sonography using a pocket-size ultrasound device in the point-of-care setting

PURPOSE

Ultrasound is commonly used in urology. Technical advances with reduced size and cost led to diffusion of small ultrasound devices to many clinical settings. Even so, most ultrasound studies are performed by non-urologists. We aimed to evaluate the utility of a pocket-size ultrasound device (Vscan™ GE Healthcare) and the quality of urologist performed study.

METHODS

Three consecutive studies were performed: (1) a urologist using the pocket ultrasound, (2) a sonographist using the pocket ultrasound, and (3) a sonographist using a standard ultrasound device. Thirty-six patients were evaluated with a basic urologic ultrasound study. An excepted deviation between studies was preset for numeric parameters and t test performed. Ordinal parameters were analyzed using Cohen's kappa coefficient.

RESULTS

Kidney length, renal pelvis length, renal cyst diameter, post-void residual and prostate volume (transabdominal) differences were found to be insignificant when comparing a urologist pocket ultrasound study to a sonographist standard ultrasound study (P = 0.15; P = 0.21; P = 0.81; P = 0.32; P = 0.07, respectively). Hydronpehrosis evaluation (none, mild, moderate and severe) and the presence of ureteral jet signs conferred a high inter-observer agreement when comparing the above studies using the Cohen's kappa coefficient (K = 0.63; K = 0.62, respectively).

CONCLUSIONS

Urologist performed pocket ultrasound study is valid in evaluating the upper and lower urinary tract and is practical in many clinical scenarios. The urologic stethoscope is now becoming a reality within reach.

The feasibility and efficacy of implementing a focused cardiac ultrasound course into a medical school curriculum

BACKGROUND

Teaching cardiac ultrasound to medical students in a brief course is a challenge. We aimed to evaluate the feasibility of teaching large groups of medical students the acquisition and interpretation of cardiac ultrasound images using a pocket ultrasound device (PUD) in a short, specially designed course.

METHODS

Thirty-one medical students in their first clinical year participated in the study. All were novices in the use of cardiac ultrasound. The training consisted of 4 hours of frontal lectures and 4 hours of hands-on training. Students were encouraged to use PUD for individual practice. Finally, the students' proficiency in the acquisition of ultrasound images and their ability to recognize normal and pathological states were evaluated.

RESULTS

Sixteen of 27 (59%) students were able to demonstrate all main ultrasound views (parasternal, apical, and subcostal views) in a six-minute test. The most obtainable view was the parasternal long-axis view (89%) and the least obtainable was the subcostal view (58%). Ninety-seven percent of students correctly differentiated normal from severely reduced left ventricular function, 100% correctly differentiated a normal right ventricle from a severely hypokinetic one, 100% correctly differentiated a normal mitral valve from a rheumatic one, and 88% correctly differentiated a normal aortic valve from a calcified one, while 95% of them correctly identified the presence of pericardial effusion.

CONCLUSIONS

Training of medical students in cardiac ultrasound during the first clinical year using a short, focused course is feasible and enables students with modest ability to acquire the main transthoracic ultrasound views and gain proficiency in the diagnosis of a limited number of cardiac pathologies.

Focused cardiac ultrasound by unselected residents-the challenges

Background

Focus Cardiac Ultrasound (FoCUS) performed by internal medicine residents on call with 2 h of training can provide a means for ruling out cardiac disease, but with poor sensitivity. The purpose of the present study was to evaluate diagnostic usefulness as well as diagnostic accuracy of FoCUS following 4 h of training.

Methods

All residents on call were given a 4-h training course with an additional one-hour training course after 6 months. They were asked to provide a pre- and post-FoCUS diagnosis, with the final diagnosis at discharge as reference.

Results

During a 7 month period 113 FoCUS examinations were reported; after 53 were excluded this left 60 for evaluation with a standard echocardiogram performed on average 11.5 h after FoCUS. Examinations were performed on the basis of chest pain and dyspnoea/edema. The best sensitivity was found in terms of the detection of reduced left ventricular (LV) ejection fraction (EF) (92%), LV dilatation (85%) and pericardial effusion (100%). High values were noted for negative predictive values, although false positives were seen. A kappa > 0.6 was observed for reduced LVEF, right ventricular area fraction and dilatation of LV and left atrium. In 48% of patients pre- and post-FoCUS diagnoses were identical and concordant with the final diagnosis. Importantly, in 30% examinations FoCUS correctly changed the pre-FoCUS diagnosis.

Conclusions

A FoCUS protocol with a 4-h training program gained clinical usefulness in one third of examinations. False positive findings represented the major challenge.

Point-of-care ultrasonography improves the diagnosis of splenomegaly in hospitalized patients

Background

It is important to detect splenomegaly as it can have important diagnostic implications. Previous studies, however, have shown that the traditional physical examination is limited in its ability to rule in or rule out splenomegaly.

Objective

To determine if performing point-of-care ultrasonography (POCUS) in addition to the traditional physical examination improves the sensitivity and specificity for diagnosing splenomegaly.

Methods

This was a prospective trial of diagnostic accuracy. Physical and sonographic examinations for splenomegaly were performed by students, residents and attending physicians enrolled in an ultrasound training course. Participants received less than 1 h training for ultrasound diagnosis of splenomegaly. The findings were compared to radiographic interpretation of gold standard studies.

Setting/patients

Hospitalized adult patients at an academic medical center without severe abdominal pain or recent surgery who had abdominal CT, MRI or ultrasound performed within previous 48 h.

Results

Thirty-nine subjects were enrolled. Five patients had splenomegaly (12.5 %). The physical examination for splenomegaly had a sensitivity of 40 % (95 % CI 12–77 %) and specificity of 88 % (95 % CI 74–95 %) while physical examination plus POCUS had a sensitivity of 100 % (95 % CI 57–100 %) and specificity of 74 % (95 % CI 57–85 %). Physical examination alone for splenomegaly had an LR+ of 3.4 (95 % CI 0.83–14) and LR− of 0.68 (95 % CI 0.33–1.41); for physical exam plus POCUS the LR+ was 3.8 (2.16–6.62) and LR− was 0.

Conclusions

Point-of-care ultrasonography significantly improves examiners’ sensitivity in diagnosing splenomegaly.

The use of a pocket-sized ultrasound device improves physical examination: results of an in- and outpatient cohort study

Background

The performance of pocket mobile ultrasound devices (PUDs) is comparable with that of standard ultrasonography, whereas the accuracy of a physical examination is often poor requiring further tests to assess diagnostic hypotheses. Adding the use of PUD to physical examination could lead to an incremental benefit.

Aim

We assessed whether the use of PUD in the context of physical examination can reduce the prescription of additional tests when used by physicians in different clinical settings.

Methods

We conducted a cohort impact study in four hospital medical wards, one gastroenterological outpatient clinic, and 90 general practices in the same geographical area. The study involved 135 physicians who used PUD, after a short predefined training course, to examine 1962 consecutive patients with one of 10 diagnostic hypotheses: ascites, pleural effusion, pericardial effusion, urinary retention, urinary stones, gallstones, biliary-duct dilation, splenomegaly, abdominal mass, abdominal aortic aneurysm. According to the physicians’ judgment, PUD examination could rule out or in the diagnostic hypothesis or require further testing; the concordance with the final diagnosis was assessed. The main outcome was the proportion of cases in which additional tests were required after PUD. The PUD diagnostic accuracy was assessed in patients submitted to further testing.

Findings

The 1962 patients included 37% in-patients, 26% gastroenterology outpatients, 37% from general practices. Further testing after PUD examination was deemed unnecessary in 63%. Only 5% of patients with negative PUD not referred for further testing were classified false negatives with respect to the final diagnosis. In patients undergoing further tests, the sensitivity was 91%, and the specificity 83%.

Conclusions

After a simple and short training course, a PUD examination can be used in addition to a physical examination to improve the answer to ten common clinical questions concerning in- and outpatients, and can reduce the need for further testing.

Feasibility and accuracy of point-of-care pocket-size ultrasonography performed by medical students

BACKGROUND

Point-of-care ultrasound performed by clinicians is a useful supplement in the treatment and assessment of patients. We aimed to investigate whether medical students with minimal training were able to successfully acquire and interpret ultrasound images using a pocket-size imaging device (PSID) as a supplement to their clinical practice.

METHODS

Thirty 5th year (of six) medical students volunteered to participate. They were each given a personal PSID device to use as a supplement to their physical examination during their allocated hospital terms. Prior to clinical placement the students were given three evenings of hands-on training with PSID by a board certified radiologist/cardiologist, including three short lectures (<20 min). The students were shown basic ultrasound techniques and taught to assess for basic, clinically relevant pathology. They were specifically instructed to assess for the presence or absence of reduced left ventricular function (assessed as mitral annular excursion < 10 mm), pericardial effusion, pleural effusion, lung comets, hydronephrosis, bladder distension, gallstones, abdominal free-fluid, cholecystitis, and estimate the diameter of abdominal aorta and inferior vena cava.

RESULTS

A total of 211 patients were examined creating 1151 ultrasound recordings. Acceptable organ presentation was 73.8% (95% CI 63.1-82.6) for cardiovascular and 88.4% (95% CI: 80.6-93.6) for radiological structures. Diagnostic accuracy was 93.5% (95% CI: 89.0-96.2) and 93.2% (95% CI: 87.4-96.5) respectively.

CONCLUSION

Medical students with minimal training were able to use PSID as a supplement to standard physical examination and successfully acquire acceptable relevant organ recordings for presentation and correctly interpret these with great accuracy.