[Feasibility of hand-held-ultrasonography in the screening of abdominal aortic aneurysms and abdominal aortic atherosclerosis]

Ultrasound screening for abdominal aortic aneurysm in primary care

INTRODUCTION

Abdominal aortic aneurysm (AAA) constitutes a pathology with high mortality. There is currently no screening program implemented in primary care in Spain.

OBJECTIVES

To evaluate the usefulness of ultrasound in the detection of AAA in the at-risk population in primary care. Secondarily, to identify subjects whose vascular risk (VR) should be reclassified and to determine whether AAA is associated with the presence of carotid plaque and other risk factors.

MATERIAL AND METHODS

Cross-sectional, descriptive, multicenter, national, descriptive study in primary care.

SUBJECTS

A consecutive selection of hypertensive males aged between 65 and 75 who are either smokers or former smokers, or individuals over the age of 50 of both sexes with a family history of AAA.

MEASUREMENTS

Diameter of abdominal aorta and iliac arteries; detection of abdominal aortic and carotid atherosclerotic plaque. VR was calculated at the beginning and after testing (SCORE).

RESULTS

One hundred and fifty patients were analyzed (age: 68.3±5 years; 89.3% male). Baseline RV was high/very high in 55.3%. AAA was detected in 12 patients (8%; 95% CI: 4-12); aortic ectasia in 13 (8.7%); abdominal aortic plaque in 44% and carotid plaque in 62% of the participants. VR was reclassified in 50% of subjects. The detection of AAA or ectasia was associated with the presence of carotid plaque, current smoking and lipoprotein(a), p<0.01.

CONCLUSIONS

The prevalence of AAA in patients with VR is high. Ultrasound in primary care allows detection of AAA and subclinical atherosclerosis and consequently reclassification of the VR, demonstrating its utility in screening for AAA in the at-risk population.

Echoscopy in scanning abdominal diseases in a critical care setting

BACKGROUND AND AIMS

Targeted ultrasound examinations with portable ultrasound device (handheld ultrasound system [HHUS]) have been defined as "echoscopy" by the European Federation of Societies of Ultrasound in Medicine and Biology (EFSUMB). For abdominal diseases it has been shown that echoscopy is sensitive and specific. The aim of this study is to show that the use of HHUS for abdominal ultrasonography is possible under the conditions prevailing in emergency and intensive care medicine and that it is not inferior to high-end devices (high-end ultrasound systems [HEUS]).

METHODS

Examinations were carried out with a first-generation Vscan™ (GE Medical Systems, Solingen, Germany) and HEUS device (Siemens Acuson X‑300 or X‑700, Siemens Healthcare, Erlangen, Germany). The HEUS device was seen as standard. The examinations were randomized and blinded and carried out by two examiners within 30 min in order to avoid falsifications due to time delay. They took place in the intensive care unit, the emergency room and the emergency medical service. The results had to be recorded in an examination sheet.

RESULTS

In all, 86 patients (54 men and 32 women, aged 73 ± 14.58 [28-95] years) were included. In 45.35% (39/86) of the ultrasound examinations using HEUS and in 41.86% (36/89) of the cases using HHUS the examination conditions were optimal. Furthermore, 76.19% of the examinations were carried out by both examiners in the same scanning position. For the detection of liver tumours, HHUS shows a sensitivity of 70% and specificity of 100%. With regard to identifying signs of cholecystitis, i.e., evidence of surrounding inflammation (a) or hydrops (b), HHUS shows a sensitivity of 66.67% (a) and 60% (b) and a specificity of 97.06% (a) and 96.86% (b). The diagnosis of an ileus is successful with a sensitivity of 87.5% and a specificity of 60%. The respiratory variability of the inferior vena cava has a sensitivity of 100% and a specificity of 40% using HHUS. Ascites and pleural effusions can be diagnosed with a sensitivity of 89% and a specificity of 93.1%. When using the FAST (Focused Assessment with Sonography for Trauma) protocol, HHUS has a sensitivity of 80% and a specificity of 90.9%. With the exception of kidney cysts and inferior vena cava, the measurement of the diameter has a positive correlation.

CONCLUSION

Echoscopy of the abdomen in emergency and intensive care medicine is possible despite restrictive circumstances. The inferior vena cava can only be assessed to a limited extent with the first generation of Vscan™. In order to use sonography in emergency and intensive care medicine, a standardized procedure is to be aimed for and training in emergency sonography is necessary.

Feasibility and Efficiency Study of a Population-Based Abdominal Aortic Aneurysm Screening Program in Men and Women in Spain

BACKGROUND

Based on current evidence, one-time screening for abdominal aortic aneurysm (AAA) in men using ultrasound evaluation reduces mortality related to AAA rupture and is considered cost-effective, although all-cause mortality reduction still remains in question. In Spain, there is no population screening program for AAA, so the aim of our study was to perform a pilot population screening program in our area to assess feasibility and efficiency of an AAA screening program for men and women.

METHODS

A population AAA screening pilot program was performed in a Barcelona area, including 400,000 inhabitants. According to inclusion criteria, 4,730 individuals aged 65 years at the moment of the trial were invited for screening (2,089 men and 2,641 women). Primary care doctors, trained in duplex ultrasound abdominal evaluations, performed an abdominal aortic measurement. Individuals with a previous diagnosis of AAA, limited life expectancy, or wrong contact data were excluded. Participation data, aortic diameters, AAA prevalence, and related cardiovascular risk factors were analyzed. The results were used in a cost-utility model to assess the efficiency of the screening program.

RESULTS

Participation was 50.3% in men and 44% in women. Eleven patients were excluded because of previously diagnosed AAA. Five new asymptomatic AAA were detected in 65-year-old men (0.5% prevalence), all being active smokers. When considering patients excluded for previous AAA diagnosis, the prevalence in 65-year-old men reached 1.4%. Global AAA prevalence in smoking men reached 2.67%. No AAA was detected in women. Subaneurysmal aorta prevalence in men was 2.9% (n = 29), and in women, it was 0.08% (n = 2). A cost-utility analysis model on screening versus no screening retrieved 13,664€ per quality-adjusted life years at a 10-year horizon and 39,455€ per quality-adjusted life years at a 30-year horizon.

CONCLUSIONS

AAA population-based screening by ultrasound evaluation in primary care is logistically feasible in our area. Despite that, AAA prevalence is lower than expected in men, and null in women. Cost-utility model results indicate that a local AAA screening program is only efficient in a 30 years' time horizon. Such inefficient results for a population screening make it necessary to consider other strategies such as opportunistic or subgroup screening in our area.

Abdominal aortic aneurysm. Prevalence and associated risk factors in a population of patients hospitalised in Internal Medicine

OBJECTIVES

To determine the prevalence of previously undiagnosed abdominal aortic aneurysm (AAA) in patients hospitalised in a department of internal medicine, as well as the associated risk factors.

PATIENTS AND METHODS

An observational, cross-sectional, single-centre, randomised study was conducted on 241 patients hospitalised in Internal Medicine. The patients were older than 50 years, had no previous diagnosis of AAA and underwent clinical ultrasonography. The dependent variable was the presence or absence of an aneurysm. The independent variables were age, sex, cardiovascular risk factors, cardiovascular disease, renal function, ankle brachial index (ABI), family history (first degree) of AAA or of early ischaemic heart disease. A bivariate and multivariate analysis was conducted in the statistical analysis.

RESULTS

The prevalence of AAA was 2.9% (95% CI: 0.8-5). The cases were confirmed through ultrasonography or computed tomography by the Department of Radiology. All patients were men with a history of smoking and with an age≥65 years. The bivariate analysis found an association between being male (OR, 9.39), smoking (OR, 13.08), ischaemic heart disease (OR, 5.6; 95% CI: 1.21-25.91; P<.05) and ABI<0.9 (OR, 12.50; 95% CI: 2.34-66.77; P<.05). In the multivariate analysis, the independently associated variable was an ABI<0.9 (OR, 10.758; 95% CI: 1.968-58.815; P=.006).

CONCLUSIONS

The prevalence of undiagnosed AAA in patients older than 50 years hospitalised in internal medicine was 2.9%. The data lead us to recommend AAA screening for this population of male patients with a history of smoking and an ABI<0.9. Clinical ultrasonography enables this screening in a reliable manner.

[Point of Care Ultrasound in Primary Care. Is it a high resolution tool?]

El modelo «Point of Care Ultrasound» es una forma de hacer ecografía clínica rápida con un fin: responder a una cuestión clínica de forma inmediata. No es hacer ecografía de modo sistemático como la que hacen los radiólogos, ni pretende sustituirla. Es útil en alguna forma de cribado (aneurisma de aorta abdominal) y es de especial interés en procedimientos ecoguiados (infiltraciones articulares).

Permite adecuar las derivaciones, minimizando la incertidumbre y descartando determinadas enfermedades por su elevada precisión diagnóstica. Pero puede llevarnos al sobrediágnostico si las exploraciones que realizamos son no limitadas a los órganos sobre los que está fundamentada nuestra sospecha clínica.

La ecografía es una herramienta más del proceso diagnóstico, pero que debe ser limitada en su utilización a determinadas situaciones clínicas. Su uso en la detección precoz de enfermedades prevalentes en Atención Primaria deberá ser convenientemente evaluado.Y, por otra parte, con gran evidencia de alta precisión diagnóstica en un gran elenco de entidades patológicas.

Abdominal aortic aneurysm screening program using hand-held ultrasound in primary healthcare

We determined the feasibility of abdominal aortic aneurysm (AAA) screening program led by family physicians in public primary healthcare setting using hand-held ultrasound device. The potential study population was 11,214 men aged ≥ 60 years attended by three urban, public primary healthcare centers. Participants were recruited by randomly-selected telephone calls. Ultrasound examinations were performed by four trained family physicians with a hand-held ultrasound device (Vscan^®). AAA observed were verified by confirmatory imaging using standard ultrasound or computed tomography. Cardiovascular risk factors were determined. The prevalence of AAA was computed as the sum of previously-known aneurysms, aneurysms detected by the screening program and model-based estimated undiagnosed aneurysms. We screened 1,010 men, with mean age of 71.3 (SD 6.9) years; 995 (98.5%) men had normal aortas and 15 (1.5%) had AAA on Vscan^®. Eleven out of 14 AAA-cases (78.6%) had AAA on confirmatory imaging (one patient died). The total prevalence of AAA was 2.49% (95%CI 2.20 to 2.78). The median aortic diameter at diagnosis was 3.5 cm in screened patients and 4.7 cm (p<0.001) in patients in whom AAA was diagnosed incidentally. Multivariate logistic regression analysis identified coronary heart disease (OR = 4.6, 95%CI 1.3 to 15.9) as the independent factor with the highest odds ratio. A screening program led by trained family physicians using hand-held ultrasound was a feasible, safe and reliable tool for the early detection of AAA.

[Economic evaluation studies in diagnostic imaging: justification and critical reading]

First, this article describes the concepts and tools most widely used for economic evaluation in healthcare. Second, it discusses some elements that must be taken into account in the social decision about how much we are willing to spend to prolong a person's life by one year. Third, it describes the criteria recommended for the critical analysis of publications that evaluate the economic aspects of health interventions. Finally, several studies about ultrasound screening for aneurysms of the abdominal aorta are used as illustrative examples to show how these elements and criteria can be applied.

National trends in incidence and outcomes of abdominal aortic aneurysm among elderly type 2 diabetic and non-diabetic patients in Spain (2003-2012)

BACKGROUND

This study aims to describe trends in the rate of abdominal aortic aneurysm (AAA) and use of open surgery repair (OSR) and endovascular aneurysm repair (EVAR) in elderly patients with and without type 2 diabetes in Spain, 2003-2012.

METHODS

We select all patients with a discharge of AAA using national hospital discharge data. Discharges were grouped by diabetes status: type 2 diabetes and no diabetes. In both groups OSR and EVAR were identified. The incidence of discharges attributed to AAA were calculated overall and stratified by diabetes status and year. We calculated length of stay (LOHS) and in-hospital mortality (IHM). Use of OSR and EVAR were calculated stratified by diabetes status. Multivariate analysis was adjusted by age, sex, year, smoking habit and comorbidity.

RESULTS

From 2003 to 2012, 115,020 discharges with AAA were identified. The mean age was 74.91 years and 16.7% suffered type 2 diabetes. Rates of discharges due to AAA increased significantly in diabetic patients (50.09 in 2003 to 78.23 cases per 100,000 in 2012) and non diabetic subjects (69.24 to 78.66). The incidences were higher among those without than those with diabetes in all the years studied. The proportion of patients that underwent EVAR increased for both groups of patients and the open repair decreased. After multivariate analysis we found that LOHS and IHM have improved over the study period and diabetic patients had lower IHM than those without diabetes (OR 0.81; 95%CI 0.76-0.85).

CONCLUSIONS

Incidence rates were higher in non-diabetic patients. For diabetic and non diabetic patients the use of EVAR has increased and open repair seems to be decreasing. IHM and LOHS have improved from 2003 to 2012. Patients with diabetes had significantly lower mortality.

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.