Pocket-Sized Echocardiography Devices: One Stop Shop Service?

Accuracy of Pocket-sized Ultrasound Devices to Evaluate Inferior Vena Cava Diameter and Variability in Critically Ill Patients

Purpose

By using inferior vena cava (IVC) measurements, clinicians can detect fluid status and responsiveness and find out the etiology of hypotension, acute heart failure, and sepsis easier. Pocket-sized ultrasound devices (PSUD) may take this advantage a few steps further by their lower costs, user-friendly interface, and easily applicable structure.In this study, we aimed to determine the diagnostic value of a PSUD compared with a standard ultrasound device (SD) for the measurement of IVC diameter (IVCD) and its respiratory variability.

Materials and methods

We measured the inspiratory, expiratory diameters of IVC, and calculated the inferior vena cava collapsibility index (IVCCI). We investigated 42 intensive care unit (ICU) patients.

Results

There was no difference in inspiratory (PSUD: 1.34 ± 0.67 cm; SD: 1.35 ± 0.68 cm) and expiratory (PSUD: 1.98 ± 0.53 cm; SD: 2.01 ± 0.49 cm) IVCD among measurements with PSUD and SD (p > 0.05). There was also no difference between IVCCI's measured with PSUD (39 ± 20%) and SD (39 ± 20%) (p > 0.05). The Bland-Altman analysis revealed that the width of 95% limits of agreement were similar for both devices. There was a good inter-device agreement among PSUD and SD for measurements of IVCD, and there was no difference between IVCCI's measured using both ultrasound devices.

Conclusion

We support that the idea of a PSUD is as reliable as a SD for IVC measurements.

How to cite this article

Inci K, Gürsel G. Accuracy of Pocket-sized Ultrasound Devices to Evaluate Inferior Vena Cava Diameter and Variability in Critically Ill Patients. Indian J Crit Care Med 2024;28(4):369-374.

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.

Feasibility and clinical utility of real-time tele-echocardiography using personal mobile device-based pocket echocardiograph

INTRODUCTION

Recently introduced microUSB ultrasound probe, which can be connected to personal mobile device constitutes a new class of diagnostic pocket size imaging devices (PSID).The aim of this study was to assess the feasibility and clinical utility of real-time tele-echocardiography with the use such device.

MATERIAL AND METHODS

The study group comprised 30 patients (18 men and 12 women; mean age: 54 ±14 years; mean body mass index: 27 ±6 kg/m²), admitted to various hospital departments (infectious diseases, internal medicine and cardiology). All patients underwent focused echocardiographic examination performed by an inexperienced operator using PSID and collaborating remotely in real-time with cardiologist by means of tele-consultation. Before commencing the examination, the operators underwent 1 h training in use of the PSID.

RESULTS

In most of patients PSID imaging provided sufficient diagnostic image quality. The dimensions of left ventricle, left atrium and the aorta obtained during the this examination showed good correlation with standard echocardiography (r = 0.89, r = 0.82, r = 0.92 respectively), but the correlation for TAPSE measurements was less pronounced (r = 0.52). The agreement in detection of pathologies (wall motion abnormalities, morphological and functional valvular abnormalities) between the tele-echocardiography and standard echocardiographic examination was good to very good (κ ranged from 0.648 to 0.823).

CONCLUSIONS

Pocket size imaging devices allows an inexperienced operator to perform a focused echocardiographic examination under a remote supervision of an experienced cardiologist. The introduction of new technology in the form of PSID with tele-echocardiography feature can revolutionize access to this imaging technique.

Ultrasound-guided internal jugular venipuncture using pocket-sized versus standard ultrasound devices: a prospective non-inferiority trial

PURPOSE

Pocket-sized ultrasound devices (PUDs) are commonly adopted for bedside use despite their inferior performance compared with standard ultrasound devices (SUDs). We investigated the non-inferiority of PUDs versus SUDs for ultrasound-guided internal jugular venipuncture.

METHODS

All patients undergoing scheduled surgery with general anesthesia and internal jugular vein catheter placement were prospectively included in this randomized non-inferiority trial to compare the qualities of the internal jugular venipuncture between the PUD group (Group P) and SUD group (Group S). The primary endpoint was puncture time, and the secondary endpoints included number of punctures, needle and guidewire visibility, and anatomic visibility.

RESULTS

Fifty-two patients were randomized to one of the two groups (26 per group). The mean (SEM) puncture time was 56.4 (10.9) s in Group P and 45.5 (4.0) s in Group S. The mean difference of 10.9 s was within the prespecified non-inferiority margin of 100% (two-sided 95% CI: - 12.9-34.6, upper limit of the 95% CI: 45.5) for puncture time. The mean (SEM) number of punctures was 1.15 (0.12) times in Group P and 1.12 (0.06) times in Group S. The difference of 0.04 punctures was within the prespecified non-inferiority margin of 100% (two-sided 95% CI: - 0.24-0.31, upper limit of the 95% CI: 1.12) for number of punctures. Non-inferiority was not shown for needle and guidewire visibility and anatomic visibility.

CONCLUSION

PUDs for internal jugular venipuncture are not inferior to SUDs with regard to puncture time and number of punctures, despite differences in visibility and device performance.

Global prevalence of congenital heart disease in school-age children: a meta-analysis and systematic review

BACKGROUND

Congenital heart disease (CHD) is the commonest birth defect. Studies estimating the prevalence of CHD in school-age children could therefore contribute to quantifying unmet health needs for diagnosis and treatment, particularly in lower-income countries. Data at school age are considerably sparser, and individual studies have generally been of small size. We conducted a literature-based meta-analysis to investigate global trends over a 40-year period.

METHODS AND RESULTS

Studies reporting on CHD prevalence in school-age children (4-18 years old) from 1970 to 2017 were identified from PubMed, EMBASE, Web of Science and Google Scholar. According to the inclusion criteria, 42 studies including 2,638,475 children, reporting the prevalence of unrepaired CHDs (both pre-school diagnoses and first-time school-age diagnoses), and nine studies including 395,571 children, specifically reporting the prevalence of CHD first diagnosed at school ages, were included. Data were combined using random-effects models. The prevalence of unrepaired CHD in school children during the entire period of study was 3.809 (95% confidence intervals 3.075-4.621)/1000. A lower proportion of male than female school children had unrepaired CHD (OR = 0.84 [95% CI 0.74-0.95]; p = 0.001). Between 1970-1974 and 1995-1999, there was no significant change in the prevalence of unrepaired CHD at school age; subsequently there was an approximately 2.5-fold increase from 1.985 (95% CI 1.074-3.173)/1000 in 1995-1999 to 4.832 (95% CI 3.425-6.480)/1000 in 2010-2014, (p = 0.009). Among all CHD conditions, atrial septal defects and ventricular septal defects chiefly accounted for this increasing trend. The summarised prevalence (1970-2017) of CHD diagnoses first made in childhood was 1.384 (0.955, 1.891)/1000; during this time there was a fall from 2.050 [1.362, 2.877]/1000 pre-1995 to 0.848 [0.626, 1.104]/1000 in 1995-2014 (p = 0.04).

CONCLUSIONS

Globally, these data show an increased prevalence of CHD (mainly mild CHD conditions) recognised at birth/infancy or early childhood, but remaining unrepaired at school-age. In parallel there has been a decrease of first-time CHD diagnoses in school-age children. These together imply a favourable shift of CHD recognition time to earlier in the life course. Despite this, substantial inequalities between higher and lower income countries remain. Increased healthcare resources for people born with CHD, particularly in poorer countries, are required.

Value of lung ultrasound score for evaluation of blast lung injury in goats

PURPOSE

To establish a severe blast lung injury model of goats and investigate the feasibility of lung ultrasonic score in the evaluation of blast lung injury.

METHODS

Twenty female healthy goats were randomly divided into three groups by different driving pressures: 4.0 MPa group (n = 4), 4.5 MPa group (n = 12) and 5.0 MPa group (n = 4). The severe blast lung injury model of goats was established using a BST-I bio-shock tube. Vital signs (respiration, heart rate and blood pressure), lung ultrasound score (LUS), PO₂/FiO₂ and extravascular lung water (EVLW) were measured before injury (0 h) and at 0.5 h, 3 h, 6 h, 9 h, 12 h after injury. Computed tomography scan was performed before injury (0 h) and at 12 h after injury for dynamic monitoring of blast lung injury and measurement of lung volume. The correlation of LUS with PaO₂/FiO₂, EVLW, and lung injury ratio (lesion volume/total lung volume*100%) was analyzed. All animals were sacrificed at 12 h after injury for gross observation of lung injury and histopathological examination. Statistical analysis was performed by the SPSS 22.0 software. The measurement data were expressed as mean ± standard deviation. The means of two samples were compared using independent-sample t-test. Pearson correlation analysis was conducted.

RESULTS

(1) At 12 h after injury, the mortality of goats was 0, 41.67% and 100% in the 4.0 Mpa, 4.5 MPa and 5.0 MPa groups, respectively; the area of pulmonary hemorrhage was 20.00% ± 13.14% in the 4.0 Mpa group and 42.14% ± 15.33% in the 4.5 MPa group. A severe lung shock injury model was established under the driving pressure of 4.5 MPa. (2) The respiratory rate, heart rate, LUS and EVLW were significantly increased, while PaO₂/FiO₂ was significantly reduced immediately after injury, and then they gradually recovered and became stabilized at 3 h after injury. (3) LUS was positively correlated with EVLW (3 h: r = 0.597, 6 h: r = 0.698, 9 h: r = 0.729; p < 0.05) and lung injury ratio (12 h: r = 0.884, p < 0.05), negatively correlated with PaO₂/FiO₂ (3 h: r = -0.871, 6 h: r = -0.637, 9 h: r = -0.658; p < 0.05).

CONCLUSION

We established a severe blast lung injury model of goats using the BST-I bio-shock tube under the driving pressure of 4.5 MPa and confirmed that ultrasound can be used for quick evaluation and dynamic monitoring of blast lung injury.

Prognostic value of point-of-care ultrasound during cardiac arrest: a systematic review

BACKGROUND

Despite significant improvements in cardiopulmonary resuscitation, sudden cardiac arrest is one of the leading causes of mortality in the United States. Ultrasound is a widely available tool that can be used to evaluate the presence of cardiac wall motion during cardiac arrest. Several clinical studies have evaluated the use of ultrasound to visualize cardiac motion as a predictor of mortality in cardiac arrest patients. However, there are limited data summarizing the prognostic value of point of care ultrasound evaluation during resuscitation. We performed a systematic literature review of the existing evidence examining the clinical utility of point-of-care ultrasound evaluation of cardiac wall motion as a predictor of cardiac resuscitation outcomes.

METHODS/RESULTS

We performed a systematic PubMed search of clinical studies up to July 23, 2019 evaluating point-of-care sonographic cardiac motion as a predictor of mortality following cardiac resuscitation. We included studies written in English that reviewed short-term outcomes and included adult populations. Fifteen clinical studies met inclusion criteria for assessing cardiac wall motion with point-of-care ultrasound and outcomes following cardiac resuscitation. Fourteen of the fifteen studies showed a statistically significant correlation between the presence of cardiac motion on ultrasound and short-term survival. This was most evident in patients with ventricular fibrillation or ventricular tachycardia as a presenting rhythm. Absence of cardiac motion non-survival. The data were pooled and the overall pooled odds ratio for return of spontaneous circulation in the presence of cardiac motion during CPR was 12.4 +/1 2.7 (p <  0.001).

CONCLUSION

Evaluation of cardiac motion on transthoracic echocardiogram is a valuable tool in the prediction of short-term cardiac resuscitation outcomes. Given the safety and availability of ultrasound in the emergency department, it is reasonable to apply point-of-care ultrasound to cardiopulmonary resuscitation as long as its use does not interrupt resuscitation.

Personal mobile device-based pocket echocardiograph-The diagnostic value and clinical utility

PURPOSE

A microUSB ultrasound probe, which can be connected to a personal mobile device constitutes a new class of diagnostic pocket-size imaging devices (PSID). The aim of this study was to assess the feasibility and diagnostic value of brief transthoracic echocardiographic examination (bTTE) performed with the use of such equipment.

MATERIAL AND METHODS

The study population comprised 87 consecutive patients (58 men, mean age 61 ± 16 years), 53 of whom were admitted to intensive cardiac care unit and 34 patients, who were referred for transthoracic echocardiography from outpatient clinic. All patients underwent bTTE performed by cardiologist with the use of personal mobile device-based PSID. Within 18 h of bTTE all subjects underwent a standard TTE (sTTE) using a full sized echocardiograph by expert echocardiographer.

RESULTS

In all patients, PSID imaging provided sufficient diagnostic image quality. Echocardiographic measurements were completed for both bTTE and sTTE in 98% of patients. The linear measurements obtained during bTTE showed good to excellent correlation with sTTE results (r = 0.65-0.98; p < 0.001). The agreement in detection of various pathologies between the bTTE and sTTE examination was very good (k = 0.62-0.97; p < 0.01).

CONCLUSION

Personal mobile device-based PSID allows for performing bTTE. The diagnostic value of such PSID in basic assessment of cardiac morphology and function as compared to standard echocardiography is very good.

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.

Patient screening for early detection of aortic stenosis (AS)-review of current practice and future perspectives

In Europe, approximately one million people over 75 years suffer from severe aortic stenosis (AS), one of the most serious and most common valve diseases, and this disease burden is increasing with the aging population. A diagnosis of severe symptomatic AS is associated with an average life expectancy of 2-3 years and necessitates a timely valve intervention. Guidelines for valve replacement therapy have been established but only a proportion of patients with symptomatic AS actually receive this life-saving treatment. The decision for valve intervention in asymptomatic patients with severe AS is often more challenging and likely results in fewer patients receiving treatment in comparison to their symptomatic counterparts. This article reviews the epidemiology and clinical manifestations of AS, the associated economic burden of AS to the healthcare system, the diagnosis of AS and the possible mechanisms for the introduction of routine screening in elderly patients. Elderly patients typically visit healthcare providers more frequently than younger patients, thereby providing increased opportunities for ad hoc AS screening and this, along with raising patient awareness of the symptoms of AS, has the potential to result in the earlier diagnosis and treatment of AS and increased patient survival.

[Use of pocket-sized ultrasound in internal medicine (hospitalist) practice: Feedback and perspectives]

INTRODUCTION

Point of care ultrasound (POCUS) is routinely used by intensivists and emergency physicians for many years. Its interest is not arguable any more for these specialists, despite the large variety of diseases they care. Hospitalists and internists also should find some interest in POCUS, which convenience and wide range of indications responds well to the variety of their practice. However, it is still not widely used in internal medicine departments.

METHODS

We here report our experience of using a pocket-sized ultrasound device in a French internal medicine department. The device used was a Vscan Dual Probe, GE, whose two probes and presets allow for cardiac, abdominal, pulmonary, obstetric, vascular, pulmonary, and superficial soft tissue exploration. One physician of the ward received a course for POCUS that was initially dedicated for emergency physicians. This study reports on the results of the examinations made between January and September 2015. For each examination performed, clinical usefulness was assessed at the time of patient discharge, by two independent physicians who reviewed the clinical course and the results of conventional imaging and rated their evaluation on a Likert scale.

RESULTS

One hundred and four examinations were evaluated. The mean duration of the ultrasound examination was 9±5minutes. The POCUS conclusions were corrected by disease course or the results of conventional imaging in 10 (9.6%) cases. The presets of the device: heart, soft tissue, lung, abdomen and vascular were used respectively in 32, 30, 21, 12 and 5% of the examinations. The main indications of POCUS examination were for identification of pleural, pericardial or peritoneal effusion, and to assess the central venous pressure by inferior vena cava examination. Eighteen examinations were performed for puncture of effusion. The retrospectively evaluated clinical benefit was clearly demonstrated in 78% of cases. The agreement between the two blinded assessors was good (kappa coefficient at 0.82).

CONCLUSION

Pocket-sized ultrasound device could be used in internal medicine wards. However, its limited performance compared to more sophisticated echography limits the possible explorations and their reliability, which encourages caution and makes critical the question of the initial training of doctors and medical students.

Can Diaphragm Dysfunction Be Reliably Evaluated with Pocket-Sized Ultrasound Devices in Intensive Care Unit?

Background

Diaphragm dysfunction (DD) is frequently seen in critically ill patients, and ultrasound could be a useful tool to detect it and to predict extubation success or failure in mechanically ventilated patients. Besides, it would also be useful in differential diagnosis of dyspnea and respiratory failure. The aim of this study is to evaluate usefulness and accuracy of pocket-sized ultrasound devices (PSDs) in assessment of DD in intensive care unit (ICU) patients in comparison with standard ultrasound devices (SD).

Methods

In this prospective observational study, we compared the performance of PSD and SD in visualization of diaphragm, detection of paradoxical movement, measurement of tidal and maximal thickness, tidal and maximal excursion, and calculation of thickening fraction (TF) of the diaphragm. We used Bland and Altman test for agreement and bias analysis and intraclass correlation analysis to evaluate interobserver variability.

Results

Thirty-nine patients were included in the study. In 93% of the patients, diaphragm was visualized with PSD. There was very good agreement between the measurements of the devices, and there was no proportional bias in the measurements of tidal inspiratory and expiratory thickness, tidal TF, tidal excursion, and maximal inspiratory thickness. In interobserver reliability analysis of all measurements for both devices, ICC coefficients were higher than 0.8. Total diaphragm examination times of the devices were similar (p > 0.05).

Conclusion

These results suggest that PSD can be useful in ICU patients for evaluating DD. But further studies are required to determine the exact place of these devices in evaluation of DD in ICU patients.

Deployed military general internal physician’s toolkit: the recent past and near future

Introduction

The role of the military physician in Deployed Hospital Care involves the diagnosis and management of a wide variety of disease states. Broad clinical skills need to be complemented by judicious use of a limited array of investigations. No study has specifically quantified what investigations physicians use on operations.

Methods

A retrospective cross-sectional study was performed to ascertain what investigations were undertaken on all patients managed by the General Internal Medicine teams over a 14 month period during a recent enduring operation in Afghanistan. A record was also made of investigations that were unavailable but considered desirable by the treating physician in order to inform clinical or occupational decisions.

Results

676 patients were admitted during the study period. Blood tests were performed in 96% of patients, plain radiographs in 50%, CT in 12% and ultrasound in 12%. An ECG was performed in over half (57%) and a peak flow in 11%. The most desirable, but unavailable, investigations were cardiac monitoring and echocardiography (24% and 12% of patients, respectively).

Discussion

The data produced by this study both identified and quantified the investigations used by physicians during a mature operational deployment. This can be used in addition to accurate medical intelligence to inform and rationalise the diagnostic requirements for future operations as well as the provision of training. Technological advancements, particularly in weight and portability, are likely to enable more complex investigational modalities to be performed further forward on military deployments.

Hand-held Ultrasound Scanners in Medical Education: A Systematic Review

Background

Ultrasound imaging devices are becoming popular in clinical and teaching settings, but there is no systematic information on their use in medical education. We conducted a systematic review of hand-held ultrasound (HHU) devices in undergraduate medical education to delineate their role, significance, and limitations.

Methods

We searched Cochrane, PubMed, Embase, and Medline using the strategy: [(Hand-held OR Portable OR Pocket OR "Point of Care Systems") AND Ultrasound] AND (Education OR Training OR Undergraduate OR "Medical Students" OR "Medical School"). We retained 12 articles focusing on undergraduate medical education. We summarised the patterns of HHU use, pooled and estimated sensitivity, and specificity of HHU for detection of left ventricular dysfunction.

Results

Features reported were heterogeneous: training time (1-25 hours), number of students involved (1-an entire cohort), number of subjects scanned (27-211), and type of learning (self-directed vs. traditional lectures + hands-on sessions). Most studies reported cardiac HHU examinations, but other anatomical areas were examined, e.g. abdomen and thyroid. Pooled sensitivity 0.88 [95% confidence interval (CI) 0.83-0.92] and specificity 0.86 (95% CI 0.81-0.90) were high for the detection of left ventricular systolic dysfunction by students.

Conclusion

Data on HHU devices in medical education are scarce and incomplete, but following training students can achieve high diagnostic accuracy, albeit in a limited number of (mainly cardiac) pathologies. There is no consensus on protocols best-suited to the educational needs of medical students, nor data on long-term impact, decay in proficiency or on the financial implications of deploying HHU in this setting.

Group A Streptococcus, Acute Rheumatic Fever and Rheumatic Heart Disease: Epidemiology and Clinical Considerations

OPINION STATEMENT

Early recognition of group A streptococcal pharyngitis and appropriate management with benzathine penicillin using local clinical prediction rules together with validated rapi-strep testing when available should be incorporated in primary health care. A directed approach to the differential diagnosis of acute rheumatic fever now includes the concept of low-risk versus medium-to-high risk populations. Initiation of secondary prophylaxis and the establishment of early medium to long-term care plans is a key aspect of the management of ARF. It is a requirement to identify high-risk individuals with RHD such as those with heart failure, pregnant women, and those with severe disease and multiple valve involvement. As penicillin is the mainstay of primary and secondary prevention, further research into penicillin supply chains, alternate preparations and modes of delivery is required.

Characterization of the rdar morphotype, a multicellular behaviour in Enterobacteriaceae

The rdar morphotype, a multicellular behaviour of Salmonella enterica and Escherichia coli is characterized by the expression of the adhesive extracellular matrix components cellulose and curli fimbriae. The response regulator CsgD, which transcriptionally activates the biosynthesis of the exopolysaccharide cellulose and curli, also transforms cell physiology to the multicellular state. However, the only role of CsgD in cellulose biosynthesis is the activation of AdrA, a GGDEF domain protein that mediates production of the allosteric activator cyclic-di-(3'-5')guanylic acid (c-di-GMP). In S. enterica serovar Typhimurium a regulatory network consisting of 19 GGDEF/EAL domain-containing proteins tightly controls the concentration of c-di-GMP. c-di-GMP not only regulates the expression of cellulose, but also stimulates expression of adhesive curli and represses various modes of motility. Functions of characterized GGDEF and EAL domain proteins, as well as database searches, point to a global role for c-di-GMP as a novel secondary messenger that regulates a variety of cellular functions in response to diverse environmental stimuli already in the deepest roots of the prokaryotes.