Hrev_master [page 28] [Emergency Care Journal 2015; 11:5017] Point-of-care critical ultra- sound in a rural emergency department Mirko Zanatta, Piero Benato, Sigilfredo De Battisti, Concetta Pirozzi, Vito Cianci Emergency Department, Arzignano Hospital, Local Health Unit Ovest, Arzignano (VI), Italy Abstract Point-of-care critical ultrasound (CCUS) has changed the management of critically ill patients in the emergency department. It is brought to the bed of patient, images are immediately available and therapy can be mon- itored making real time changes. Although it is difficult to estimate the real efficacy of CCUS, we evaluated the impact of ultrasound in our emergency department. This study is a cross sectional observational study with 241 cases enrolled. All patients were evaluated by the emergency physician and underwent clinical examination and then CCUS. Patients were then independently evaluated by at least one consultant. A final diagnosis was made after an agreement between the emergency physi- cian and the consultant. Percentages of correct final diagnosis were higher after CCUS than after primary survey: 82.5% vs 49.1% of patients with dyspnea (P<0.001), 71.9% vs 40.6 % with thoracic pain (P=0.03), 76.2% vs 45% with abdominal pain (P<0.001), 80.0% vs 43.6% with suspected deep venous thrombosis (P=0.03) and 80.0% vs 20% with shock (P=0.014). Extended fast assessment for trau- ma was effective for the management of trau- matic patients and correctly ruled out compli- cations in 81.1% of patients (P=0.04). A small number of ultrasound guided invasive proce- dures were safely and successfully performed. In our study the integration of primary survey with CCUS increased diagnostic capability of the emergency physician and improved overall quality of medical assistance. Introduction Point-of-care critical ultrasound (CCUS) improves diagnostic capabilities, reduces com- plications of invasive procedures and is effec- tive in the management of critically ill patients.1 CCUS’s portability, feasibility and cost effectiveness have determined a world- wide diffusion of the technique. Ultrasound (US) technology was integrated in the emer- gency department (ED) in the last decades to help the rapid identification of the etiology of diseases and to integrate physical examina- tion, which is often not reliable enough.2,3 Point-of-care critical ultrasound is brought to the bed of patients, images are immediately available and interpreted according with clini- cal symptoms and signs. It can be either multi- organ in more complex and critical conditions (cardiac arrest, unknown hypotension, shock)4-6 or focal, limited, goal-directed to answer just one or few clinical questions (deep venous thrombosis, renal colic, pneumotho- rax).1 The emergency physician (EP) can also monitor the effectiveness of medical therapy making real time changes of diagnostic and therapeutic procedures.7,8 Point-of-care critical ultrasound has broken some old and untouchable barriers, like those represented by lungs [lung ultrasound (LUS)];8 critical care echocardiography (CCEC) has been introduced in critical care area and it is now a useful instrument for the EP;9 fast assessment for trauma (FAST), fol- lowed by the extended FAST to lung injuries (EFAST), is worldwide considered as a valid protocol for the management of trauma;10,11 CCUS is successfully used in some remote set- tings, like rural and desert areas, in the space and in war scenarios.12,13 For the same reason, CCUS has been intro- duced in pre-hospital settings, in the ambu- lance and in small hospitals where diagnostic tools are limited and where the radiologist and the majority of specialists are not available 24 hours a day. Although it is difficult to estimate the real impact of CCUS in these settings, aim of the study was to evaluate the role of CCUS on diag- nostic and therapeutic procedures in our emergency department. We compared diagno- sis made after primary survey, after ultrasound and by a specialist and we evaluated the per- centages of cases in which CCUS had been decisive in obtaining a definite diagnosis. Materials and Methods We planned an observational study and we enrolled 241 consecutively clinical cases from July 2013 until December 2013 in the emer- gency departments of Cazzavillan Hospital in Arzignano (VI), Italy. It is a medium size emer- gency department with a mean of 35,000 accesses per year. Patients were screened during the daily shifts (from 8 to 20 o’clock) when all the con- sultants and radiologists are usually available in our hospital. Cases were consecutively sam- pled whenever one of the designated ultra- sound operators were on duty. Criteria for enrollment included the pres- ence of one of the following syndrome and are summarized in Table 1: shock or cardiac arrest, dyspnea, non traumatic chest pain, abdominal pain, trauma involving chest and/or abdomen, a suspected diagnosis of deep venous thrombosis. Firstly all patients underwent primary sur- vey (PS) during which physicians collected information about patient’s history, signs, symptoms and physical examination. Electrocardiography and a point-of-care blood hemogasanalysis were also immediately avail- able during PS. Point-of-care critical ultrasound was then performed by the same emergency physician. Further examinations (both laboratory and radiological) were prescribed when necessary and at least one independent consultant evalu- ation was collected. The emergency physician filled in an elec- tronic worksheet where he reported the follow- ing steps: supposed diagnosis after primary survey, CCUS performed, supposed diagnosis after CCUS, other diagnostic procedures per- formed, a comment upon the role of CCUS. Discharge diagnosis was the reference point and it was made after the examination of clinical, laboratory and radiological documen- tations of every patient by the EP together with the consultant. Cases without agreement were classified as not determined. Emergency Care Journal 2015; volume 11:5017 Correspondence: Mirko Zanatta, Emergency Department, Arzignano Hospital, Local Health Unit Ovest Ovest, Via Parco 1, 36071 Arzignano (VI), Italy. Tel: +39.044.4479261 - Fax: +39.044.4479267. E-mail: mirko.zanatta@ulss5.it Key words: Critical ultrasound; Emergency department; Rural hospital; Diagnosis. Contributions: MZ, PB and VC contributed to the conception of the study, acquisition of data and drafting the article; SDB and CP contributed to the acquisition of data and images; MZ and VC contributed to the final approval of the version to be published. Conflict of interest: VC reports receiving personal funds from the World Interactive Network Focused on Critical Ultrasound (WINFOCUS), outside the present work; while the other authors declare no potential conflict of interest. Received for publication: 23 January 2015. Revision received: 8 April 2015. Accepted for publication: 27 April 2015. This work is licensed under a Creative Commons Attribution 3.0 License (by-nc 3.0). ©Copyright M. Zanatta et al., 2015 Licensee PAGEPress, Italy Emergency Care Journal 2015; 11:5017 doi:10.4081/ecj.2015.5017 Non co mmerc ial us e o nly [Emergency Care Journal 2015; 11:5017] [page 29] Ultrasound examinations were grouped into 6 categories: 1- LUS; 2- CCEC; 3- Abdominal US (AUS); 4- Multiorgan Ultrasound (MU); 5. EFAST; 6- CUS (compression ultrasonogra- phy). Number and type of invasive procedures were also registered. We compared diagnosis made after each step (after PS, after CCUS and definitive diagnosis) and the improvement of diagnostic capability obtained by the applica- tion of CCUS was evaluated. For traumatic patients the main goal was the detection of a major complications of trauma: pneumothorax, lung contusion, pleural and pericardial effu- sion, haemoperitoneum. Emergency physi- cians were also asked to comment upon the role of CCUS after every case according to the following classification: crucial for diagnosis, supported the clinical data, simply ruled out a suspected diagnosis, misleading. Primary end- point was the estimation of the improvement of diagnostic capability obtained by CCUS com- paring the diagnosis made after PS and CCUS with discharge diagnosis. Secondary endpoints was the evaluation of the feasibility of CCUS in all the different clinical situations faced in the emergency department and the assessment of the appreciation perceived by the emergency physicians. The study was approved by local committee. Informed consent was collected, even if it was not possible to obtain it from critically ill and unconscious subjects or affected by cardiac arrest. Point-of-care critical ultrasound technique Point-of-care critical ultrasound was always performed after PS. Focused assessments were used for localized and well defined symptoms [renal colic, cholecystitis, pneumothorax, deep vein thrombophlebitis (DVT)], while a multi- organ approach was chosen in complex syn- dromes or in critically ill patients. We applied some specific protocols: EFAST in trauma, CUS for deep venous thrombosis, Rapid Ultrasound in SHock (RUSH) and multiorgan ultrasono- graphic (MU) approach in patients with shock, cardiac arrest, unknown hypotension.14 CUS was integrated with the dosage of D-dimer for those patients with normal ultrasound find- ings but with a high preclinical Wells score (data not shown). If D-dimer had been higher than normal, patients would have been instructed to perform a doppler ultrasound within 10 days, while patients with normal D- dimer test would have safely discharged with- out any anticoagulant therapy.15,16 Some invasive procedures were also guided by US: central venous catheterization, thora- centesis, paracentesis, abscess drainage. All scans were performed in two dimensional grey scale with the patient in a supine upright posi- tion using an Esaote Mylab 30 with a curvilin- ear probe (2-5 MHz) for LUS, AUS, EFAST and multiorgan ultrasound, a sector probe (2-3 MHz) for CCEC and a linear 7-12 MHz probe for CUS, LUS and to guide invasive proce- dures. Operators were certified emergency physicians who had accomplished the compe- tency training program for UltraSound Life Support (Basic Management/Level 1 - Provider) provided by Winfocus. Statistical analysis We expressed as percentages admission symptoms, type of US performed, correct and incorrect diagnosis made after PS and CCUS and the role of CCUS. Diagnosis made after PS and after CCUS were then expressed as correct and incorrect with respect to definitive diagno- sis and differences were calculated using chi- square analysis. Fisher’s exact test was used for the analysis of smaller groups. Invasive procedures were excluded from statistical analysis and the number of failures and side effects were only reported. Results were con- sidered statistically significant for P value lower than 0.05. Statistical analysis was made using SPSS 16.0. Results Five hundred and seventy-four patients had been initially evaluated for the study and 241 were finally recruited: 113 women (47.2%; mean age 55.35±22.77, minimum 12, maxi- mum 99 years old) and 128 men (52.8%; mean age 56.33±21.61; minimum 14, maximum 94 years old). The majority of patients were excluded at the time of data analysis for incomplete documentation, wrong triage diag- nostic evaluation and lack of consultant evalu- ation. Percentages of symptoms and ultra- sounds are described respectively in Table 1 and in Figure 1. After PS a true positive diagnosis was made in 49.1% of subjects with dyspnea, 40.6% of patients with chest pain, 45.0% of patients with abdominal pain, 40.0% of patients with suspected deep venous thrombosis and 20% of shocks. Diagnostic capability significantly increased after CCUS, which fulfilled largely our primary endpoint (Figure 2). A final clinical diagnosis was achieved in 82.5% of patients with dysp- nea (+33.4% in comparison with PS alone) (P<0.001), 71.9% of patients with chest pain (+31.3%) (P=0.03), in 76.2% of patients with abdominal pain (+31.2%) (P<0.001), in 80.0% of patients with suspected deep venous throm- bosis (+36.4%) (P=0.03) and in 80% of shocks (+60%) (P=0.014). We did not register any new deep venous thrombosis in those patients with a high pre- clinical Wells score and a high D-Dimer who performed a second examination within 10 days from the previous one. In traumatic patients emergency physicians suspected a complication of trauma in 32.4% of cases after PS. Instead, complications were correctly identified in 81.1% of cases by EFAST (+48.7%) (P=0.04). We performed 18 invasive procedures: 7 Article Table 1. Summary of inclusion symptoms and percentages of patients recruited. Syndrome Symptoms Patients (%) Dyspnea A-traumatic, acute* respiratory insufficiency (Oximetry<88%), shortness of breath, cough, fever with mild hypoxia (Oximetry<93%) 23.7 Chest pain A-traumatic, acute*, well localized or irradiated, spontaneous, independent of movements, with/without tachycardia, nausea, cold sweet, feeling faint/tired 13.3 Abdominal pain A-traumatic, acute*, well-localized or a-specific, cramp-like or steady and unrelenting, with or without fever, nausea, vomit and constipation 33.2 Trauma Trauma involving thorax and/or abdomen 15.4 Suspect of DVT of lower limb A-traumatic swelling and/or warm and reddened skin and/or spontaneous pain and/or venous cord 12.4 Shock or cardiac arrest Cardiac arrest, shock with or without unconsciousness, unknown hypotension 2.1 DVT, deep vein thrombophlebitis. *Acute onset, <24 h. Non co mmerc ial us e o nly [page 30] [Emergency Care Journal 2015; 11:5017] jugular vein catheterization, 1 femoral vein catheterization, 4 thoracentesis, 3 paracente- sis, 2 arthrocentesis and 1 abdominal abscess drainage. One jugular vein catheterization failed in a patient affected by hypovolemic shock while we did not registered any compli- cations. Finally 4.7% of cases were classified as undetermined. Regarding our secondary endpoint, CCUS was performed in all cases faced in the study period of time. It never lasted more than 5 min- utes, with some examinations that lasted less than 10 seconds (CCUS in cardiac arrest). According to the physicians’ opinion, CCUS was crucial for the final diagnosis in 27.6% of cases, supported or confirmed clinical data in 56.1% of patients, ruled out specific clinical hypothesis without being decisive for the diag- nosis in 14.2% of subject and was misleading in the remaining 2.1%, thus receiving much appreciation by all the operators. A schematic representation of the utility of CCUS is sum- marized in Table 2. Misleading diagnosis was determined by a wrong interpretation of ultrasonographic images: a patient with a thoracic trauma sus- pected of having PNX after LUS and eventually affected by a large pulmonary bullae; a focal inferior hypokinesia of the left ventricle not confirmed by the cardiologist in a patient with nonspecific ST segment modifications and epi- gastric pain; one patient with jaundice and ultrasonographic evidence of gallbladder stones, but affected by chronic heart failure and congestive liver; a suspect of pulmonary embolism in a patient with right ventricle dilatation, chronic obstructive pulmonary dis- ease and a final diagnosis of septic shock; a female with a fortuitous and not complicated peritoneal effusions in the pouch of Douglas. The percentage of patients admitted to the hospital was 40.9%, 1.2% died (all cases were subjects with cardiac arrest), and the remain- ing 57.9% was discharged. Within each syn- drome the percentages of admission and dis- charge were respectively 62.9% vs 37.1% for dyspnea, 37% vs 63% for thoracic pain, 32.4% vs 67.6% for trauma, 37.5% vs 62.5% for abdominal pain and 16% vs 84% for patients suspected of having DVT. All patients with shock or resuscitated were admitted to the hospital. Article Table 2. A schematic representation of secondary endpoints. Syndrome CCUS crucial for the diagnosis (%) CCUS supported clinical data (%) Ruled out clinical hypothesis (%) Misleading (%) Dyspnea 22.8 68.4 8.8 0.0 Chest pain 53.1 18.8 21.9 6.2 Abdominal pain 58.8 27.5 11.2 2.5 Trauma 16.2 64.9 16.2 2.7 Suspect of DVT 60.0 20.0 20.0 0.0 Shock/cardiac arrest 42.9 28.6 14.3 14.3 CCUS, point-of-care critical ultrasound: DVT, deep vein thrombophlebitis. The role of point-of-care critical ultrasound is described for each syndrome according with physicians’ judgement. Figure 2. Percentages of correct final diagnosis registered after primary survey and pri- mary survey + point-of-care critical ultrasound. The number of definitive diagnosis improved significantly after the use of ultrasound. Figure 1. Percentages of ultrasounds performed. Non co mmerc ial us e o nly [Emergency Care Journal 2015; 11:5017] [page 31] Discussion Point-of-care critical ultrasound has dramat- ically changed the management of critically ill patients in the emergency department. Many papers have stressed the importance of CCUS in critical care area, but the majority of them are focused on specific topics or syndromes. In our work we tried to do something more, eval- uating the role of CCUS in the daily clinical practice of a rural emergency departments, where different and concomitant syndrome are usually faced and where a radiologist and a consultant are not always available. Firstly, we strongly stresses the importance of primary survey: ultrasound must integrate clinical assessment without replacing it. However, physical examination is not always possible or sufficient, for example in noisy environments, in not collaborating patients, in pre-hospital settings or in the ambulance. Moreover, physical examination is not reliable enough in mild syndromes and in those patients with many concurrent pathologies. For example, a mild heart failure is hardly diagnosed with the stethoscope and the X-ray will identify lung congestion if intrathoracic water exceeds the normal intrathoracic vol- ume by 75%.14 Lung ultrasound is important for the man- agement of dyspnea: B lines on pleural ultra- sonography predict fluid overload, adding diag- nostic accuracy to the physical examination and measurement of brain natriuretic peptide (Figure 3);17 pneumothorax and pleural effu- sions are rapidly and effectively diagnosed.7 In our study the percentage of correct diag- noses after lung ultrasound was extremely high and the emergency physicians were able to discriminate rapidly and effectively between a wet and a dry lung and to rule in or rule out pleural effusions or a pneumothorax. We also confirmed the feasibility of CUS for the man- agement of patients with a suspect of deep venous thrombosis as shown by the high per- centage of final correct diagnosis (Figure 3). According with other papers,18 our experience showed that learning curve of CUS had been extremely rapid for all the operators. Patients with abdominal symptoms often required the examination of different organs, but functional bowel disorders of the intestine reduced diagnostic accuracy of ultrasound in several cases. In our study the role of CCUS was often important even when it wasn’t decisive for the diagnosis: for example the possibility to rule out life-threatening syndromes, like an abdom- inal aortic aneurysm in patients with intense abdominal pain, reduced concern and anxiety of operators (Figure 3B). As far as trauma is concerned, the majority of EFAST were per- formed to exclude complications of traumatic injuries. Many studies have demonstrated that FAST reduces the need for CT and the time for an appropriate intervention, providing evi- dences of shorter hospital stay, lower costs and lower overall mortality.19 In our experience EFAST gave the indication to proceed directly to a CT scan or to surgery only in a minority of cases, but the possibility to rule out complica- tions, such as hidden effusions, pneumothorax or lung contusions, was important for the man- agement of trauma, safe-discharge, decision to transport or to not transport patients to the nearest trauma center. The use of critical care echocardiography in the ED has also increased but it remains the most difficult technique. Although CCEC is currently considered a crucial expertise for the emergency physician, this covers a limited dif- ferential diagnosis: to acquire standard transthoracic views in advanced life support maneuver, to identify major causes of cardiac arrest and shock, to recognize when a referral to a second opinion is indicated.9 In our analy- sis CCEC improved the management of chest pain and shock, but since heart diseases are complex, the assessment of a cardiologist remained often compulsory. Multiorgan ultrasound based on the RUSH protocol or on the multiorgan ultrasonographic protocol was performed in those cases with haemodynamic instability, shock, unknown hypotension and cardiac arrest.5,6 Images Article Figure 3. A) B lines in pulmonary oedema (arrows). B) Large abdominal aortic aneurysm. C) A young woman with cardiac arrest and massive pulmonary embolism: acute right ventricle (RV) overload (C1) and a thrombus inside the vena cava (C2, arrow). D) deep venous thrombosis: hyperchoic material and lack of compressibility of femoral (D1, arrow) and popliteal vein (D2, arrow). LV, left ventricle. Non co mmerc ial us e o nly [page 32] [Emergency Care Journal 2015; 11:5017] obtained from different organs were integrat- ed with clinical symptoms and physiopathology (Figure 3). It is a new and interesting evolution of CCUS since a rapid and accurate diagnosis is important especially in patients with symp- toms that could be manifestations of different pathologies with different or even opposite treatments. Hypotension determined by hypov- olemia requires fluid challenge, but fluid chal- lenge can rapidly deteriorate a hypotension secondary to an impaired cardiac function; thrombolysis is indicated when severe hypotension or cardiac arrest are associated with right ventricle overload due to massive pulmonary embolism (Figure 3), but it is con- traindicated in hemorrhagic shock; invasive procedures are life saving in cardiac tampon- ade; immediate surgery is compulsory in patients with shock, abdominal pain and sus- pected of having a ruptured abdominal aortic aneurysm. A multiorgan approach gives also the chance to monitor treatments and to change therapy according with ultrasono- graphic findings.20,21 Finally, a small number of invasive proce- dures were performed. Multiple studies have confirmed that ultrasound improves success and decreases complications in central and peripheral vascular access, thoracentesis, paracentesis, arthrocentesis, regional anes- thesia, incision and drainage of abscesses, localization and removal of foreign bodies, lumbar puncture, biopsies, and other proce- dures.22 In 2012 international evidence-based recommendations on ultrasound-guided vas- cular access were published and according with them ultrasound guidance has to be sug- gested as the method of choice for any kind of vascular cannulation given its higher safety and efficacy.23 Our study has certainly some limitations. First of all ultrasounds were not blinded with respect to primary survey since they were both performed by the same physician, thus influ- encing the interpretation of ultrasound find- ings: but, as previously explained we aimed to evaluate the impact of ultrasound in the real life of the emergency department where clini- cal examination and CCUS is always, or nearly always, performed by the same physician. Other limitations were the absence of a control group, the lack of a reliable comparison of diagnostic capability among operators (differ- ent medical background, experiences) and the difficulty to calculate the real importance of CCUS in those cases in which ultrasound sim- ply ruled out a specific life-threatening hypoth- esis. Despite the above mentioned limitations, we think that our study confirms the impor- tance to integrate primary survey with CCUS. The possibility to obtain a visual diagnosis rather than just a clinical hypothesis improved overall quality of medical assistance together with satisfaction of patients and reduced con- cern and anxiety of medical operators. Comments of emergency physicians upon the role of CCUS confirmed their appreciation for ultrasound: in the majority of cases CCUS was either crucial for diagnosis or supported/rein- forced clinical data. The small percentages of misleading diag- nosis was mainly determined by a wrong inter- pretation of ultrasonographic images and by the lack of integration of clinical information with ultrasound analysis. Despite the small number of cases we want to focused once more our attention both on the importance to inte- grate CCUS with primary survey and clinical assessment for a correct interpretation of data and to the collaboration between emergency physicians and consultants to improve the management of our patients. Conclusions Although the limitations of the study design, the integration of primary survey with CCUS increased diagnostic capability of the emer- gency physician and improved rapidity and quality of medical assistance. Point-of-care critical ultrasound must not replace primary survey as well as the referral to a consultant, like echocardiography performed by a cardiolo- gist or diagnostic ultrasonography performed by a radiologist. Collaborations between differ- ent specialists are often necessary and advis- able, but the emergency physician’s proficien- cy in ultrasound is in a unique position to obtain real-time information and incorporate it with clinical assessments, thus facilitating the management of critically ill patients, pre- venting possible delays, improving quality and reducing medical costs. References 1. Christopher L, Moore MD, Joshua A, Copel MD. Point-of-care ultrasonography. New Engl J Med 2011;364:749-57. 2. Arntfield RT, Millington SJ. Point-of-care cardiac ultrasound applications in the emergency department and intensive care unit: a review. Curr Cardiol Rev 2012;8:98- 108. 3. Lichtenstein D, Goldstein I, Mourgeon E, et al. Comparative diagnostic performanc- es of auscultation, chest radiography, and lung ultrasonography in acute respiratory distress syndrome. Anesthesiology 2004;100:9-15. 4. Rose JS, Bair AE, Mandavia D, Kinser DJ. The UHP ultrasound protocol: a novel ultrasound approach to the empiric evalu- ation of the undifferentiated hypotensive patient. Am J Emerg Med 2001;19:299-302. 5. Perera P, Mailhot T, Riley D, Mandavia D. The RUSH exam: rapid ultrasound in shock in the evaluation of the critically III. Emerg Med Clin N Am 2010;28:29-56. 6. Volpicelli G, Lamorte A, Tullio M, et al. Point-of-care multiorgan ultrasonography for the evaluation of undifferentiated hypotension in the emergency depart- ment. Intens Care Med 2013;39:1290-8. 7. Volpicelli G, Elbarbary M, Blaivas M, et al. International Liaison Committee on Lung Ultrasound (ILC-LUS) for International Consensus Conference on Lung Ultrasound (ICC-LUS). International evi- dence-based recommendations for point- of-care lung ultrasound. Intens Care Med 2012;38:577-91. 8. Haydar SA, Moore ET, Higgins GL 3rd, et al. Effect of bedside ultrasonography on the certainty of physician clinical decision making for septic patients in the emer- gency department. Ann Emerg Med 2012;60:e344. 9. Price S, Via G, Sloth E, et al. Echocardiography practice, training and accreditation in the intensive care: docu- ment for the World Interactive Network Focused on Critical Ultrasound (WINFO- CUS). Cardiovasc Ultrasoun 2008;6:49. 10. Scalea TM, Rodriguez A, Chiu WC, et al. Focused assessment with sonography for trauma (FAST): results from an interna- tional consensus conference. J Trauma 1999;46:466-72. 11. Kirkpatrick AW, Sirois M, Laupland KB, et al. 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