Transesophageal echocardiography predicts mortality in critically ill patients with unexplained hypotension

Anterolateral papillary muscle suction causing low flow in a COVID-19 patient without medical history: a case report of central extracorporeal life support with left ventricular apex decompression

BACKGROUND

Left ventricular (LV) decompression is an essential strategy for improving early survival in patients with refractory cardiogenic shock. Low pump flow in patients on extracorporeal life support (ECLS) with LV apex decompression is a life-threatening issue. However, identifying the underlying causes of low flow can be challenging.

CASE PRESENTATION

A 38-year-old woman with COVID-19-related fulminant myocarditis was treated with central ECLS with LV apex decompression. The pump flow in the intensive care unit (ICU) was intermittently low, and low flow alerts were frequent. The initial evaluation based on pressure monitor waveforms and transthoracic echocardiography failed to identify the underlying cause. Prompt bedside transesophageal echocardiography (TEE) revealed that the anterolateral papillary muscle was suctioned into the vent cannula of the LV apex during systole. The patient underwent a repeat sternal midline incision in the operating room, and the cannula at the LV apex was repositioned. There were no further suction events after the repositioning, and the patient was weaned from ECLS 12 days after admission to the ICU. The patient was discharged in a stable condition and without neurological deficits.

CONCLUSIONS

TEE is an important diagnostic tool to identify the underlying cause of low flow flow in patients undergoing ECLS with LV apex decompression.

The Significance of Equipment Availability and Anesthesia Educational Conferences to Decision-Making for EKG Lead V5 Abnormalities

Introduction To predict postoperative myocardial infarction rates in patients who undergo noncardiac surgery, the Canadian Cardiovascular Society Guidelines on Perioperative Cardiac Risk Assessment and Management recommends assessment of brain natriuretic peptide (BNP) in certain patients. Serial troponins are measured if the BNP level is elevated. In certain cases, Revised Cardiac Risk Index (RCRI) alone does not perform well, for example, during vascular surgery. Cardiac events occur in 20% of all vascular surgery patients. The odds ratio for such events is 9.2 if ST segments were depressed by 1 mm intraoperatively (relative to the PR interval) within the first 48 hours postoperatively. Increasing the number of cables and pads from three to five for electrocardiogram (EKG) increases the sensitivity from around 30% to over 80% for ischemic events relative to a formal EKG stress test, and then the monitor continuously displays not only lead II but also lead V5. Methods Our hypothesis was that raising awareness about diagnostic and therapeutic options to reduce the risk of postoperative myocardial infarction would increase the use of five pads. We conducted open-ended surveys at six hospitals to assess the reasons for choosing three pads. In our university hospital practice, we measured a cross-sectional incidence of using three pads before and, once again, a month after an intervention during a single morning. Several resident conferences encouraged the use of five pads. Education included weekly lectures and informal discussions with other staff during surgery, demonstrating that using five pads allows interrogation of an entire 12-lead EKG. In comparison, three pads only allow viewing three leads. Results At baseline, only three pads were available in 96% of our 23 operating rooms. Five cables were available in eight of those surgeries, but two were taped off to the side. Surveys unveiled scarcity of equipment and, more importantly, disempowerment (i.e., knowing how to diagnose or when to treat ischemia). After several conferences, the prevalence of equipment availability of only three pads fell to 47%. Conclusions Education enumerated details of recognizing ischemic configurations of ST depression. Next, education revealed methods to interrupt the progression of ischemia to infarction such as elevated blood pressure and hematocrit, reducing heart rate, and calling a cardiology consultant if the anesthesiologist wishes to draw serial troponins. Barriers to implementing an enhanced recovery after surgery (ERAS) pathway began with a need for more access to manage stress tests or optimize blood pressure medications after a preoperative anesthesia evaluation. The intraoperative barrier was knowing what to do if ST depression occurs. Therefore, we began raising awareness by encouraging the addition of an element of a future ERAS pathway, adding a cost of only $1 to monitor lead V5. Future ERAS pathways can include preoperative stress tests and consults, as found in published guidelines.

CARDIAC OUTPUT IN CRITICALLY ILL PATIENTS CAN BE ESTIMATED EASILY AND ACCURATELY USING THE MINUTE DISTANCE OBTAINED BY PULSED-WAVE DOPPLER

ABSTRACT

Background: Cardiac output (CO) assessment is essential for management of patients with circulatory failure. Among the different techniques used for their assessment, pulsed-wave Doppler cardiac output (PWD-CO) has proven to be an accurate and useful tool. Despite this, assessment of PWD-CO could have some technical difficulties, especially in the measurement of left ventricular outflow tract diameter (LVOTd). The use of a parameter such as minute distance (MD) which avoids LVOTd in the PWD-CO formula could be a simple and useful way to assess the CO in critically ill patients. Therefore, the aim of this study was to evaluate the correlation and agreement between PWD-CO and MD. Methods: A prospective and observational study was conducted over 2 years in a 30-bed intensive care unit (ICU). Adult patients who required CO monitoring were included. Clinical echocardiographic data were collected within the first 24 h and at least once more during the first week of ICU stay. PWD-CO was calculated using the average value of three LVOTd and left ventricular outflow tract velocity-time integral (LVOT-VTI) measurements, and heart rate. Minute distance was obtained from the product of LVOT-VTI × heart rate. Pulsed-wave Doppler cardiac output was correlated with MD using linear regression. Cardiac output was quantified from the MD using the equation defined by linear regression. Bland-Altman analysis was also used to evaluate the level of agreement between CO calculated from MD (MD-CO) and PWD-CO. The percentage error was calculated. Results: A total of 98 patients and 167 CO measurements were analyzed. Sixty-seven (68%) were male, the median age was 66 years (interquartile range [IQR], 53-75 years), and the median Acute Physiology and Chronic Health Evaluation II score was 22 (IQR, 16-26). The most common cause of admission was shock in 81 patients (82.7%). Sixty-nine patients (70.4%) were mechanically ventilated, and 68 (70%) required vasoactive drugs. The median CO was 5.5 L/min (IQR, 4.8-6.6 L/min), and the median MD was 1,850 cm/min (IQR, 1,520-2,160 cm/min). There was a significant correlation between PWD-CO and MD-CO in the general population ( R2 = 0.7; P < 0.05). This correlation improved when left ventricular ejection fraction (LVEF) was less than 60% ( R2 = 0.85, P < 0.05). Bland-Altman analysis showed good agreement between PWD-CO and MD-CO in the general population, the median bias was 0.02 L/min, the limits of agreement were -1.92 to +1.92 L/min. The agreement was better in patients with LVEF less than 60% with a median bias of 0.005 L/min and limits of agreement of -1.56 to 1.55 L/min. The percentage error was 17% in both cases. Conclusion: Measurement of MD in critically ill patients provides a simple and accurate estimate of CO, especially in patients with reduced or preserved LVEF. This would allow earlier cardiovascular assessment in patients with circulatory failure, which is of particular interest in difficult clinical or technical conditions.

Head to toe ultrasound: a narrative review of experts' recommendations of methodological approaches

Critical care ultrasonography (US) is widely used by intensivists managing critically ill patients to accurately and rapidly assess different clinical scenarios, which include pneumothorax, pleural effusion, pulmonary edema, hydronephrosis, hemoperitoneum, and deep vein thrombosis. Basic and advanced critical care ultrasonographic skills are routinely used to supplement physical examination of critically ill patients, to determine the etiology of critical illness and to guide subsequent therapy. European guidelines now recommend the use of US for a number of practical procedures commonly performed in critical care. Full training and competence acquisition are essential before significant therapeutic decisions are made based on the US assessment. However, there are no universally accepted learning pathways and methodological standards for the acquisition of these skills.Therefore, in this review, we aim to provide a methodological approach of the head to toe ultrasonographic evaluation of critically ill patients considering different districts and clinical applications.

Spatiotemporal Coherence to Quantify Sources of Image Degradation in Ultrasonic Imaging

Thermal noise and acoustic clutter signals degrade ultrasonic image quality and contribute to unreliable clinical assessment. When both noise and clutter are prevalent, it is difficult to determine which one is a more significant contributor to image degradation because there is no way to separately measure their contributions in vivo. Efforts to improve image quality often rely on an understanding of the type of image degradation at play. To address this, we derived and validated a method to quantify the individual contributions of thermal noise and acoustic clutter to image degradation by leveraging spatial and temporal coherence characteristics. Using Field II simulations, we validated the assumptions of our method, explored strategies for robust implementation, and investigated its accuracy and dynamic range. We further proposed a novel robust approach for estimating spatial lag-one coherence. Using this robust approach, we determined that our method can estimate the signal-to-thermal noise ratio (SNR) and signal-to-clutter ratio (SCR) with high accuracy between SNR levels of -30 to 40 dB and SCR levels of -20 to 15 dB. We further explored imaging parameter requirements with our Field II simulations and determined that SNR and SCR can be estimated accurately with as few as two frames and sixteen channels. Finally, we demonstrate in vivo feasibility in brain imaging and liver imaging, showing that it is possible to overcome the constraints of in vivo motion using high-frame rate M-Mode imaging.

Feasibility, utility, and safety of fully incorporating transesophageal echocardiography into emergency medicine practice

INTRODUCTION

Transthoracic echocardiography (TTE) is a standard procedure for emergency physicians (EPs). Transesophageal echocardiography (TEE) is known to have great utility in patients who are critically ill or in cardiac arrest and has been used by some EPs with specialized ultrasound (US) training, but it is generally considered outside the reach of the majority of EPs. We surmised that all of our EPs could learn to perform focused TEE (F-TEE), so we trained and credentialed all of the physicians in our group.

METHODS

We trained 52 EPs to perform and interpret F-TEEs using a 4-h simulator-based course. We kept a database of all F-TEE examinations for quality assurance and continuous quality feedback. Data are reported using descriptive statistics.

RESULTS

Emergency physicians attempted 557 total F-TEE examinations (median = 10, interquartile range = 5-15) during the 42-month period following training. Clinically relevant images were obtained in 99% of patients. EPs without fellowship or other advanced US training performed the majority of F-TEEs (417, 74.9%) and 94.3% (95% confidence interval [CI] = 91.4%-96.3%) had interpretable images recorded. When TTE and TEE were both performed (n = 410), image quality of TEE was superior in 378 (93.3%, 95% CI = 89.7%-95%). Indications for F-TEE included periarrest states (55.7%), cardiac arrest (32.1%), and shock (12.2%). There was one case of endotracheal tube dislodgement during TEE placement, but this was immediately identified and replaced without complication.

CONCLUSION

After initiating a mandatory group F-TEE training and credentialing program, we report the largest series to date of EP-performed resuscitative F-TEE. The majority of F-TEE examinations (75%) were performed by EPs without advanced US training beyond residency.

Feasibility of focused cardiac ultrasound during cardiac arrest in the emergency department

Background

Focused cardiac ultrasound (FOCUS) can aid in evaluation and management of patients with cardiac arrest, but image quality in this population has been questioned. Our goal was to determine how often adequate imaging can be obtained in cardiac arrest patients.

Methods

We conducted a prospective cohort study to examine the utility of FOCUS in cardiac arrest. All patients who presented to the Emergency Department (ED) in cardiac arrest or who had cardiac arrest while in the ED over 6 months were prospectively identified. FOCUS images were obtained as part of routine clinical care. Patients with images obtained were paired with age- and gender-matched controls who underwent FOCUS for another indication during the study period. Image quality was scored by two blinded reviewers using a 0–4 scale, with a score of ≥ 2 considered adequate.

Results

There were 137 consecutive cardiac arrests, 121 out-of-hospital and 16 in-hospital, during the study period. FOCUS images were recorded in 126 (92%), who were included in the analysis. The average age was 58 years, and 45% were female. Ninety-seven studies (77%) were obtained during advanced cardiac life support while 29 (23%) were obtained after return of spontaneous circulation. The controls were appropriately matched. Of the cardiac arrest studies, 106 (84%) were rated adequate, compared to 116 (92%) in controls (p = 0.08). When compared to control FOCUS studies, the scores given to studies of cardiac arrest patients were lower (p = 0.001).

Conclusions

FOCUS can reliably be used during cardiac arrest to obtain images adequate to answer clinical questions and guide therapies.

Critical Care Echocardiography as a Routine Procedure for the Detection and Early Treatment of Cardiac Pathologies

Transthoracic and transesophageal echocardiography are important investigations in the intensive care unit (ICU) to diagnose acute cardiac pathologies and assess the haemodynamic status. Recommendations for critical care echocardiography (CCE) have been published recently, but these still lack an evidence-based foundation. It is not known if performing transthoracic echocardiography (TTE) on a routine basis instead of only when required in acute cases is feasible or clinically useful. In this single-centre prospective observational study, we routinely performed TTE on 111 consecutive non-cardiological, non-cardiothoracic surgical ICU patients in two surgical ICUs in a tertiary care facility. Significant cardiac pathologies were detected in 82 (76.6%) and critical cardiac pathologies in 33 (30.8%) of the 107 patients. The most common critical cardiac pathologies were sPAP > 50 mmHg (19.63%), tricuspid annular plane systolic excursion ≤ 13 mm (9.4%), grade III diastolic dysfunction (8.4%), severe tricuspid valve insufficiency (5.6%) and left ventricular ejection fraction (LV-EF) ˂ 30% (4.7%). Some of the most commonly found cardiac pathologies are not well emphasised in current recommendations and training programs. We observed a progression of the cardiac pathologies previously described in 41 of the patients (91.1%). Patients with echocardiographic abnormalities had a significant survival disadvantage in the ICU. By performing CCE routinely, we observed the range and prevalence of cardiac pathologies that can be detected by echocardiography in critically ill patients. We recommend routine transthoracic CCE in ICU patients for early detection of cardiac pathologies and to help inform early intervention regimens, since cardiac conditions carry a significant survival disadvantage for the ICU patient.

Hemodynamic monitoring using trans esophageal echocardiography in patients with shock

Circulatory shock is a life-threatening condition responsible for inadequate tissue perfusion. The objectives of hemodynamic monitoring in this setting are multiple: identifying the mechanisms of shock (hypovolemic, distributive, cardiogenic, obstructive); choosing the adequate therapeutic intervention, and evaluating the patient's response. Echocardiography is proposed as a first line tool for this assessment in the intensive care unit. As compared to trans-thoracic echocardiography (TTE), trans-esophageal echocardiography (TEE) offers a better echogenicity and is the best way to evaluate deep anatomic structures. The therapeutic implication of TEE leads to frequent changes in clinical management. It also allows depicting sources of inaccuracy of thermodilution-based hemodynamic monitoring. It is a semi invasive tool with a low rate of complications. The first step in the hemodynamic evaluation of shock is to characterize the mechanisms of circulatory failure among hypovolemia, vasoplegia, cardiac dysfunction, and obstruction. Echocardiographic evaluation includes evaluation of LV systolic and diastolic function, as well as RV function, pericardium, measure of stroke volume and cardiac output, and evaluation of hypovolemia and fluid responsiveness. TEE can be used as a semi-continuous monitoring tool and can be repeated before and after therapeutic interventions (vasopressors, inotropes, fluid therapy, specific treatment such as pericardial effusion evacuation) to evaluate efficacy and tolerance of therapeutic interventions. In conclusion, TEE plays an important role in the management of circulatory failure when TTE is not enough to answer to the questions, although it is not a continuous tool of monitoring. TEE results must be integrated in a global evaluation, the first step being clinical examination. Whether TEE-directed therapy and close hemodynamic monitoring of shock has an impact on outcome remains debated.

Unanticipated critical findings on echocardiography in septic patients

BACKGROUND

Echocardiography is increasingly performed among septic patients as a routine part of evaluation and management in the intensive care unit (ICU). The rate of unanticipated critical findings (e.g., severe left or right ventricular dysfunction or pericardial tamponade) on such echocardiograms is unknown. We evaluated a retrospective cohort of septic ICU patients in whom transthoracic echocardiography was performed as a routine part of sepsis management. In addition to identifying critical findings, we defined whether each critical finding was anticipated, and whether the clinical team responded to the critical finding. The primary outcome was rate of unanticipated critical findings, which we hypothesized would occur in fewer than 5% of patients. We also performed an exploratory analysis of the association between unanticipated critical finding and mortality, controlling for severity of illness.

RESULTS

We studied 393 patients. Unanticipated critical findings were identified in 5% (95% CI 3-7%) of patients (n = 20). Among the 20 patients with unanticipated critical findings, a response to the unanticipated critical finding was identified in 12 (60%) patients. An unanticipated critical finding was not significantly associated with 28-day mortality when controlling for admission APACHE II (p = 0.27).

CONCLUSIONS

Unanticipated critical findings on echocardiograms in septic ICU patients are uncommon. The potential therapeutic relevance of echocardiography to sepsis is more likely related to hemodynamic management than to traditional cardiac diagnoses. Research studies that employ blinded echocardiograms in septic patients may anticipate unblinding for critical findings approximately 1 in every 20 echocardiograms.

Critical care echocardiography and outcomes in the critically ill

PURPOSE OF REVIEW

Critical care echocardiography offers a comprehensive assessment of cardiac anatomy and function performed by the intensivist at point of care. This has resulted in widespread use of critical care echocardiography in ICUs leading to the question if this increased usage has resulted in improved patient outcomes.

RECENT FINDINGS

Recent studies have evaluated the role of critical care echocardiography in the ICU with an emphasis on establishing accurate diagnosis and measurement of haemodynamic variables. There are no prospective randomized controlled trials that have examined the effect of critical care echocardiography on patient outcomes SUMMARY: Although the effect of critical care echocardiography on patient outcomes has not yet been established, its value as a diagnostic tool has been well demonstrated. We can only assume that its diagnostic capability leads to an improvement in patient outcomes.

A decade of progress in critical care echocardiography: a narrative review

INTRODUCTION

This narrative review focusing on critical care echocardiography (CCE) has been written by a group of experts in the field, with the aim of outlining the state of the art in CCE in the 10 years after its official recognition and definition.

RESULTS

In the last 10 years, CCE has become an essential branch of critical care ultrasonography and has gained general acceptance. Its use, both as a diagnostic tool and for hemodynamic monitoring, has increased markedly, influencing contemporary cardiorespiratory management. Recent studies suggest that the use of CCE may have a positive impact on outcomes. CCE may be used in critically ill patients in many different clinical situations, both in their early evaluation of in the emergency department and during intensive care unit (ICU) admission and stay. CCE has also proven its utility in perioperative settings, as well as in the management of mechanical circulatory support. CCE may be performed with very simple diagnostic objectives. This application, referred to as basic CCE, does not require a high level of training. Advanced CCE, on the other hand, uses ultrasonography for full evaluation of cardiac function and hemodynamics, and requires extensive training, with formal certification now available. Indeed, recent years have seen the creation of worldwide certification in advanced CCE. While transthoracic CCE remains the most commonly used method, the transesophageal route has gained importance, particularly for intubated and ventilated patients.

CONCLUSION

CCE is now widely accepted by the critical care community as a valuable tool in the ICU and emergency department, and in perioperative settings.

Transesophageal Echocardiography During Cardiopulmonary Resuscitation Is Associated With Shorter Compression Pauses Compared With Transthoracic Echocardiography

STUDY OBJECTIVE

Point-of-care ultrasonography provides diagnostic information in addition to visual pulse checks during cardiopulmonary resuscitation (CPR). The most commonly used modality, transthoracic echocardiography, has unfortunately been repeatedly associated with prolonged pauses in chest compressions, which correlate with worsened neurologic outcomes. Unlike transthoracic echocardiography, transesophageal echocardiography does not require cessation of compressions for adequate imaging and provides the diagnostic benefit of point-of-care ultrasonography. To assess a benefit of transesophageal echocardiography, we compare the duration of chest compression pauses between transesophageal echocardiography, transthoracic echocardiography, and manual pulse checks on video recordings of cardiac arrest resuscitations.

METHODS

We analyzed 139 pulse check CPR pauses among 25 patients during cardiac arrest.

RESULTS

Transesophageal echocardiography provided the shortest mean pulse check duration (9 seconds [95% confidence interval {CI} 5 to 12 seconds]). Mean pulse check duration with transthoracic echocardiography was 19 seconds (95% CI 16 to 22 seconds), and it was 11 seconds (95% CI 8 to 14 seconds) with manual checks. Intraclass correlation coefficient between abstractors for a portion of individual and average times was 0.99 and 0.99, respectively (P<.001 for both).

CONCLUSION

Our study suggests that pulse check times with transesophageal echocardiography are shorter versus with transthoracic echocardiography for ED point-of-care ultrasonography during cardiac arrest resuscitations, and further emphasizes the need for careful attention to compression pause duration when using transthoracic echocardiography for point-of-care ultrasonography during ED cardiac arrest resuscitations.

Transthoracic Echocardiography: Impact on Diagnosis and Management in Tertiary Care Intensive Care Units

The purpose of this study was to evaluate the utility of transthoracic echocardiography (TTE) in an intensive care unit by determining its impact on diagnosis and management. Over a six-month time period, we performed a prospective observational study on all patients admitted to either the medical or the surgical intensive care unit. Structured interviews were conducted with referring physicians before and after the TTE to determine the referring physicians’ pre-TTE diagnosis, reasons for requesting the TTE, and whether the TTE resulted in a change in diagnosis and/or management. A total of 135 TTE examinations were done in 126 patients. The referring physicians deemed that clinical information was inadequate to make a definitive diagnosis and management plan in 36/135 (27%) of the requests. In 99/135 (73%) studies, physicians indicated that there was probably sufficient clinical information to formulate a diagnosis and management plan, but ordered a TTE to corroborate their clinical findings. Overall, a change in diagnosis occurred in 39/135 (29%) of studies, and a change in management in 55/135 (41%) of studies. Diagnosis was changed in 19/99 (19%) studies with adequate clinical data, and in 20/36 (56%) studies with inadequate clinical data (P<0.001). Management was changed in 34/99 (34%) of studies with adequate clinical data and in 21/36 (58%) of studies with inadequate clinical data (P=0.017). Of the 62 management changes, 57/62 (92%) changes were minor, and 5/62 (8%) were major. In conclusion we have found that TTE frequently resulted in a change in the diagnosis and management.

Impact of Critical Care Transesophageal Echocardiography in Medical-Surgical ICU Patients: Characteristics and Results From 274 Consecutive Examinations

OBJECTIVE

Critical care echocardiography has become an integral tool in the assessment and management of critically ill patients. Critical care transesophageal echocardiography (TEE) offers diagnostic reliability, superior image quality, and an expanded diagnostic scope to transthoracic echocardiography. Despite its favorable attributes, TEE use in North American intensive care units (ICUs) remains relatively undescribed. In this article, we seek to characterize the feasibility, indications, and clinical impact of a critical care TEE program.

DESIGN

Retrospective, observational study.

SETTING

Tertiary care, academic critical care program consisting of 2 hospitals in Ontario, Canada.

PARTICIPANTS

Consecutive critical care TEE examinations on ICU patients performed between December 2012 and December 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Consecutive critical care TEE studies on ICU patients from December 1, 2012, to December 31, 2016, were reviewed. The TEEs performed on cardiac surgery patients and those without reports were excluded. Examination details, including indications, complications, examination complexity (number of views, Doppler techniques), and clinical recommendations were aggregated and analyzed. Two hundred seventy-four TEE studies were performed by 38 operators. Common indications for TEE studies were hemodynamic instability (45.2%), assessment for infective endocarditis (22.2%), and cardiac arrest (20.1%). A change in patient management was proposed following 79.5% of TEE studies. Thirty-eight percent of TEE studies were performed during evening hours or on weekends. There were no mechanical complications.

CONCLUSIONS

Our observational data support intensivist-performed TEE as being safe and therapeutically influential across a broad range of indications. Our program's demonstrated feasibility and impact may act as a model for TEE adoption in other North American ICUs.

Emerging and Future Technologies in Out-of-Hospital Cardiac Arrest Care

The care for victims of out-of-hospital cardiac arrest is evolving and will be influenced by future and emerging technologies that will play a role in the systems of care for these patients. Recent advances in extracorporeal life support and point-of-care ultrasound imaging, both in-hospital and out-of-hospital, may offer a therapeutic solution in some systems for patients with refractory or recurrent cardiac arrest. Drones capable of delivering automated external defibrillators to the scene of an out-of-hospital cardiac arrest, advances in digital and mobile technologies to notify and leverage bystander response, and wearable life detection technologies may improve survival.

The Diagnostic and Therapeutic Impact of Point-of-Care Ultrasonography in the Intensive Care Unit

PURPOSE

In light of point-of-care ultrasonography's (POCUS) recent rise in popularity, assessment of its impact on diagnosis and treatment in the intensive care unit (ICU) is of key importance.

METHODS

Ultrasound examinations were collected through an ultrasound reporting software in 6 multidisciplinary ICU units from 3 university hospitals in Canada and the United States. This database included a self-reporting questionnaire to assess the impact of the ultrasound findings on diagnosis and treatment. We retrieved the results of these questionnaires and analyzed them in relation to which organs were assessed during the ultrasound examination.

RESULTS

One thousand two hundred and fifteen ultrasound studies were performed on 968 patients. Intensivists considered the image quality of cardiac ultrasound to be adequate in 94.7% compared to 99.7% for general ultrasound ( P < .001). The median duration of a cardiac examination was 10 (interquartile range [IQR] 10) minutes compared to 5 (IQR 8) minutes for a general examination ( P < .001). Overall, ultrasound findings led to a change in diagnosis in 302 studies (24.9%) and to a change in management in 534 studies (44.0%). A change in diagnosis or management was reported more frequently for cardiac ultrasound than for general ultrasound (108 [37.1%] vs 127 [16.5%], P < .001) and (170 [58.4%] vs 270 [35.1%], P < .001). Assessment of the inferior vena cava for fluid status emerged as the critical care ultrasound application associated with the greatest impact on management.

CONCLUSION

Point-of-care ultrasonography has the potential to optimize care of the critically ill patients when added to the clinical armamentarium of the intensive care physician.

Diagnosis and Management of Pericardial Disease

The pericardium serves many important functions but is not essential for life. Pericardial heart disease comprises only pericarditis and its complications, tamponade and constriction, and congenital lesions. However, the pericardium is affected by virtually every category of disease. Thus the critical care physician is likely to encounter the patient with pericardial disease in a variety of settings, either as an isolated phenomenon or as a complication of a variety of systemic disorders, trauma, or certain drugs. Despite exhaustive etiological lists, the cause of pericardial heart disease is often never identified. This article reviews the diagnosis and management of acute and chronic pericarditis with an emphasis on those areas of greatest interest to the intensivist.

A model and regularization scheme for ultrasonic beamforming clutter reduction

Acoustic clutter produced by off-axis and multipath scattering is known to cause image degradation, and in some cases these sources may be the prime determinants of in vivo image quality. We have previously shown some success addressing these sources of image degradation by modeling the aperture domain signal from different sources of clutter, and then decomposing aperture domain data using the modeled sources. Our previous model had some shortcomings including model mismatch and failure to recover B-Mode speckle statistics. These shortcomings are addressed here by developing a better model and by using a general regularization approach appropriate for the model and data. We present results with L1 (lasso), L2 (ridge), and L1/L2 combined (elastic-net) regularization methods. We call our new method aperture domain model image reconstruction (ADMIRE). Our results demonstrate that ADMIRE with L1 regularization, or weighted toward L1 in the case of elastic-net regularization, have improved image quality. L1 by itself works well, but additional improvements are seen with elastic-net regularization over the pure L1 constraint. On in vivo example cases, L1 regularization showed mean contrast improvements of 4.6 and 6.8 dB on fundamental and harmonic images, respectively. Elastic net regularization (α = 0.9) showed mean contrast improvements of 17.8 dB on fundamental images and 11.8 dB on harmonic images. We also demonstrate that in uncluttered Field II simulations the decluttering algorithm produces the same contrast, contrast-tonoise ratio, and speckle SNR as normal B-mode imaging, demonstrating that ADMIRE preserves typical image features.

An alternative approach to the bedside assessment of left ventricular systolic function in the emergency department: displacement of the aortic root

OBJECTIVES

Left ventricular ejection fraction (LVEF) is a crucial parameter in the management of patients with dyspnea in the emergency department (ED). The use of techniques other than echocardiography such as nuclear or magnetic resonance imaging to measure LVEF is unsuitable in the ED because of time constraints. This study aimed to compare echocardiographic aortic root (AR) excursion and LVEF measurement using the modified Simpson's method (biplane method of disks) as recommended by the American Society of Echocardiography.

METHODS

After 2 hours of theoretical video and hands-on training with 20 patients by an experienced echocardiographer, two emergency physicians prospectively evaluated patients with dyspnea. Two-dimensional echocardiograms of the parasternal long-axis view were obtained, and the displacement of the aortic root (DAR) was studied. M-mode DAR recordings were obtained, and distances were measured as the maximized anterior displacement of the AR from the horizontal axis at end-systole by using the leading-edge methodology. LVEF was measured by an experienced cardiologist using the modified Simpson's rule. The sensitivity, specificity, positive and negative likelihood ratios (LR+, LR-), and positive and negative predictive values (PPV, NPV) were analyzed. A new formula for the prediction of the ejection fraction (EF) with the aid of DAR was then created.

RESULTS

The mean (±SD) age with of the 70 study patients was 69.7 (±11.91) years. In these patients, DAR was highly correlated with EF (point biserial correlation coefficient = 0.79, p < 0.001) and one-way analysis of variance (ANOVA) results were significant (F = 115.9; p < 0.001). The sensitivity was 94.4; specificity, 94.1; LR+, 16.6; LR-, 0.059; PPV, 94.4; and NPV, 94.1.

CONCLUSIONS

The results indicate that DAR is a sensitive index of left ventricular systolic function (SF) and can be used to reliably predict EF values using the rough formula of EF = 20 + 44 (DAR).

Sepsis-induced cardiomyopathy

Myocardial dysfunction is one of the main predictors of poor outcome in septic patients, with mortality rates next to 70%. During the sepsis-induced myocardial dysfunction, both ventricles can dilate and diminish its ejection fraction, having less response to fluid resuscitation and catecholamines, but typically is assumed to be reversible within 7-10 days. In the last 30 years, It´s being subject of substantial research; however no explanation of its etiopathogenesis or effective treatment have been proved yet. The aim of this manuscript is to review on the most relevant aspects of the sepsis-induced myocardial dysfunction, discuss its clinical presentation, pathophysiology, etiopathogenesis, diagnostic tools and therapeutic strategies proposed in recent years.

Utility of echocardiography in hypotension in the intensive care unit

A prospective study was performed on the utility of echocardiography in diagnosing hypotension in critically ill patients. In our study, we found that transthoracic echocardiography can help physicians determine the etiology of hypotension in a significant number of patients. Transesophageal echocardiography is useful when results obtained from transthoracic echocardiography are suboptimal. Left ventricular function assessed by echocardiography can be used to predict 30-day mortality.

Core review: physician-performed ultrasound: the time has come for routine use in acute care medicine

The use of ultrasound in the acute care specialties of anesthesiology, intensive care, emergency medicine, and surgery has evolved from discrete, office-based echocardiographic examinations to the real-time or point-of-care clinical assessment and interventions. "Goal-focused" transthoracic echocardiography is a limited scope (as compared with comprehensive examination) echocardiographic examination, performed by the treating clinician in acute care medical practice, and is aimed at addressing specific clinical concerns. In the future, the practice of surface ultrasound will be integrated into the everyday clinical practice as ultrasound-assisted examination and ultrasound-guided procedures. This evolution should start at the medical student level and be reinforced throughout specialist training. The key to making ultrasound available to every physician is through education programs designed to facilitate uptake, rather than to prevent access to this technology and education by specialist craft groups. There is evidence that diagnosis is improved with ultrasound examination, yet data showing change in management and improvement in patient outcome are few and an important area for future research.

International expert statement on training standards for critical care ultrasonography

Training in ultrasound techniques for intensive care medicine physicians should aim at achieving competencies in three main areas: (1) general critical care ultrasound (GCCUS), (2) "basic" critical care echocardiography (CCE), and (3) advanced CCE. A group of 29 experts representing the European Society of Intensive Care Medicine (ESICM) and 11 other critical care societies worldwide worked on a potential framework for organizing training adapted to each area of competence. This framework is mainly aimed at defining minimal requirements but is by no means rigid or restrictive: each training organization can be adapted according to resources available. There was 100% agreement among the participants that general critical care ultrasound and "basic" critical care echocardiography should be mandatory in the curriculum of intensive care unit (ICU) physicians. It is the role of each critical care society to support the implementation of training in GCCUS and basic CCE in its own country.

Inadequate visualization and reporting of ventricular function from transthoracic echocardiography after cardiac surgery

OBJECTIVES

The purpose of this study was to determine the incidence of and risk factors for inadequate reporting of ventricular function from transthoracic echocardiography after cardiac surgery.

DESIGN AND SETTING

A retrospective study of cardiac surgical patients at 1 university hospital.

PATIENTS

The first 300 consecutive patients who had transthoracic echocardiogram within the first 7 days after cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcomes for this study were inadequate visualization of the left ventricle, the right ventricle, or both ventricles. Analysis of data from 300 patients identified inadequate imaging of the left ventricle in 50 (17%) cases, inadequate imaging of the right ventricle in 112 (37%) cases, inadequate imaging of both ventricles in 37 (12%) cases, and inadequate imaging of either the left or right ventricle in 125 (42%) cases. Increasing age, earlier postoperative day, male sex, and median sternotomy were associated with inadequate imaging.

CONCLUSIONS

Transthoracic imaging is often inadequate in patients who have undergone recent cardiac surgery. Patient and surgical characteristics influence reporting of right and left ventricular function.

Routine transthoracic echocardiography in a general Intensive Care Unit: an 18 month survey in 704 patients

The authors analyzed 704 transthoracic echocardiographic (TTE) examinations, performed routinely to all admitted patients to a general 16-bed Intensive Care Unit (ICU) during an 18-month period. Data acquisition and prevalence of abnormalities of cardiac structures and function were assessed, as well as the new, previously unknown severe diagnoses. A TTE was performed within the first 24 h of admission on 704 consecutive patients, with a mean age of 61.5+/-17.5 years, ICU stay of 10.6+/-17.1 days, APACHE II 22.6+/-8.9, and SAPS II 52.7+/-20.4. In four patients, TTE could not be performed. Left ventricular (LV) dimensions were quantified in 689 (97.8%) patients, and LV function in 670 (95.2%) patients. Cardiac output (CO) was determined in 610 (86.7%), and mitral E/A in 399 (85.9% of patients in sinus rhythm). Echocardiographic abnormalities were detected in 234 (33%) patients, the most common being left atrial (LA) enlargement (n=163), and LV dysfunction (n=132). Patients with these alterations were older (66+/-16.5 vs 58.1+/-17.4, p<0.001), presented a higher APACHE II score (24.4+/-8.7 vs 21.1+/-8.9, p<0.001), and had a higher mortality rate (40.1% vs 25.4%, p<0.001). Severe, previously unknown echocardiographic diagnoses were detected in 53 (7.5%) patients; the most frequent condition was severe LV dysfunction. Through a multivariate logistic regression analysis, it was determined that mortality was affected by tricuspid regurgitation (p=0.016, CI 1.007-1.016) and ICU stay (p<0.001, CI 1-1.019). We conclude that TTE can detect most cardiac structures in a general ICU. One-third of the patients studied presented cardiac structural or functional alterations and 7.5% severe previously unknown diagnoses.

Integrating echocardiography into human patient simulator training of anesthesiology residents using a severe pulmonary embolism scenario

INTRODUCTION

Echocardiographic images were integrated into patient simulation (PS)-based resident training with a goal of highlighting the applicability and limitations of pure pressure-based measurements in the management of different disease states.

METHODS

Relevant echocardiographic images were selected, categorized, and sequenced to best represent specific hemodynamic changes and incorporated into a Powerpoint slideshow. Appropriate PS scenarios were then created to represent the hemodynamic changes seen with the selected pathophysiologic states. Instructors then displayed the visual images along with PS scenarios during lecture and testing sessions at the PS bedside during standard didactic sessions with small groups of anesthesiology residents and informal resident testing sessions.

CONCLUSIONS

The use of echo images to demonstrate, in real time, the hemodynamic consequences of changes in myocardial contractility, cardiac chamber volume, and valvular function is possible during PS in anesthesiology residency training. Echo imaging as a teaching tool during anesthesiology residency may yield a greater understanding of the pathophysiology of certain disease states, ultimately leading to faster diagnosis and more appropriate intervention by anesthesiologists.

Impact of echocardiography on patient management in the intensive care unit: an audit of district general hospital practice

BACKGROUND

Echocardiography has been shown to positively impact on the management of the critically ill patient. However, many published studies have a significant bias towards inclusion of cardiothoracic patients. We present an audit of the impact of echocardiography on the management of patients in a district general hospital intensive care unit (ICU).

METHODS

We conducted a prospective audit of all echocardiograms, both transthoracic (TTE) and transoesophageal (TOE), performed on our ICU between October 1, 2005, and December 31, 2007. In addition to patient characteristics, we recorded the indication for the echocardiogram, and any change in management that occurred as a result of the study.

RESULTS

Two hundred and fifty-eight echocardiograms were performed in 217 patients, of which 224 (86.8%) were performed by intensive care consultants. One hundred and eighty-seven studies (72.4%) were TTEs and 71 (27.8%) were TOEs. TTE provided diagnostic images in 91.3% of spontaneously breathing and 84.2% of mechanically ventilated patients. Management was changed directly as a result of information provided in 51.2% of studies. Changes included fluid administration, inotrope or drug therapy, and treatment limitation.

CONCLUSIONS

Echocardiography may have a significant impact on the management of patients in the general ICU. We recommend that appropriate training in echocardiography should be incorporated into the intensive care curriculum in the UK.

The Accuracy of Diagnostic and Haemodynamic Data Obtained by Transthoracic Echocardiography in Critically Ill Adults: A Systematic Review

We systematically assessed the utility of diagnostic data and the accuracy of haemodynamic data obtained by transthoracic echocardiography in critically ill adults, by examination of prospective studies in unselected adult intensive care patients. Of the ten studies identified, three examined the diagnostic utility of transthoracic echocardiography. Thirty-eight percent of clinical questions were answered by a single transthoracic echocardiogram. The weighted mean percentage of clinical findings yielded by transoesophageal echocardiography not found by the transthoracic approach was 33% (range 28–50%).

Four studies examined the correlation between transthoracic echocardiographic estimation of pulmonary artery occlusion pressure and pulmonary artery catheter-derived measurement. Correlation was strong in all studies: for example in one study r=0.98, p<0.001, with a mean difference of 0.0 (2.5) mm Hg by the Bland-Altman technique.

Three studies examined the correlation between transthoracic echocardiography and thermodilution-derived cardiac output measurement. Correlation varied with the echocardiographic technique used and correlated best with Dopplerderived measurement: r=0.93, p<0.0001, mean difference of 0.2 (0.82) litres per minute.

The diagnostic utility of transthoracic echocardiography compared with transoesophageal echocardiography in the critically ill cannot be reliably assessed from the available studies. More relevantly designed studies are required. Transthoracic echocardiography can accurately estimate pulmonary artery occlusion pressure, but the technique requires the patient to be in sinus rhythm. Transthoracic echocardiography can also accurately estimate cardiac output in the critically ill. Further studies should concentrate on Doppler-based assessments. The scene is now set for the development of this valuable non-invasive tool.

Importance of transesophageal echocardiography in the critically ill and injured patient

Echocardiography, particularly transesophageal echocardiography (TEE), is a vital diagnostic and monitoring imaging modality for the intensivist. The field of echocardiography spans different venues and pathologies, ranging from surface transthoracic echocardiography and portable hand-held echocardiography, to contrast echocardiography, stress echocardiography, and TEE, among others. Numerous investigations have proven the worth of echocardiography, especially TEE, in the critically ill and injured patient, changing lives with the identification of obvious and subtle cardiothoracic diseases. Because this powerful imaging tool is immediately available and portable, crucial delays in diagnosis are not commonplace; rather than echocardiography, TEE, specifically, should be (and is in some institutions) the standard of care and management in assisting the intensivist in diagnosis of a variety of maladies. The effect of TEE technology is quite formidable, and numerous investigations have borne this out. The therapeutic effect of TEE ranges from 10% to 69%, with the majority of investigations falling into the 60% to 65% range. The diagnostic yield of TEE is far greater, approaching 78%. This article will detail the importance of echocardiography, its efficacy, and its high-yield imaging capability, particularly when compared with other imaging modalities, even transthoracic echocardiography.

Pericardial disease and pericardial tamponade

The pericardium serves many important functions, but it is not essential for life. Pericardial heart disease comprises only pericarditis and its complications, tamponade and constriction, and congenital lesions. However, the pericardium is affected by virtually every category of disease. The critical care physician is thus likely to encounter the patient with pericardial disease in a variety of settings, either as an isolated phenomenon or as a complication of a variety of systemic disorders, trauma, or certain drugs. Echocardiography is the primary tool for diagnosing and quantifying pericardial effusions, and in the context of the clinical presentation, a thorough understanding of M-mode, two-dimensional, and Doppler findings can help not only to identify patients with impending tamponade, but also to suggest a diagnosis of constrictive pericarditis. This article reviews the pathogenesis and diagnosis of pericardial heart disease, focusing on the diagnostic utility of echocardiography, with an emphasis on those areas of greatest interest to the intensivist.