Guiding Cardiopulmonary Resuscitation with Focused Echocardiography: A Report of Five Cases.

Background: Focused transthoracic echocardiography has been used to determine etiologies of cardiac arrest and evaluate utility of continuing resuscitation after cardiac arrest. Few guidelines exist advising ultrasound timing within the advanced cardiac life support algorithm. Natural timing of echocardiography occurs during the pulse check, when views are unencumbered by stabilization equipment or vigorous movements. However, recent studies suggest that ultrasound performance during pulse checks prolongs the pause duration of cardiopulmonary resuscitation. Transesophageal echocardiography studies have demonstrated benefits in this regard, but there have been no transthoracic echocardiography studies assessing the physical performance of compressions during cardiopulmonary resuscitation. Objective: The purpose of this study was to describe cases where echocardiography performed at the beginning of the cardiac arrest algorithm offers actionable information to cardiopulmonary resuscitation itself without delaying provision of compressions. Conclusion: Providers using focused echocardiography to evaluate cardiac arrest patients should consider initiating scans at the start of compressions to identify the optimal location for compression delivery and to detect inadequate compressions. Subsequent visualization of full left ventricular compression may be seen after a location change, and combined with end tidal carbon dioxide values, gives indication for improved forward circulatory flow. Although it is not possible in all patients, doing so hastens provision of quality compressions that affect hemodynamic parameters without causing prolongations to the pulse check pause. Further research is needed to determine patient outcomes from both out-of-hospital and in-hospital cardiac arrest when cardiopulmonary resuscitation is visually guided by focused echocardiography.

Impact of point-of-care ultrasonography on ED time to disposition for patients with nontraumatic shock.

STUDY OBJECTIVE: Nontraumatic shock in the emergency department (ED) has multiple causes and carries in-hospital mortality approaching 20%, underscoring the need for prompt diagnosis and treatment. Diagnostic ultrasonography at the point of care is one method that may improve the ability of ED physicians to quickly diagnose and treat. This study assesses the effect of the use and timing of point-of-care (POC) ultrasonography on time to disposition request. METHODS: This retrospective study across 4 Connecticut EDs compared propensity score matched shock patients who did and did not receive POC ultrasonography. Two propensity score matches were performed: the first using covariates of time to disposition from previous literature and the second using 25 novel covariates identified from electronic health records using machine learning to reduce variable selection biases. RESULTS: A total of 3834 unique patients presented with shock during an 18-month period, and 703 (18.3%) patients received POC ultrasonography. Mean time to disposition for all patients was 255.4minutes (interquartile range, 163.8). After propensity score matching, patients had a mean reduction of 26.7minutes (95% confidence interval [CI], 2.8-58.3) in time to disposition when POC ultrasonography was performed within 1hour of ED arrival and a lesser reduction of 16.7minutes (95% CI, -2.8 to 35.5) when POC ultrasonography was performed within 2hours. There was no evidence of reduction in time to disposition when ultrasonography was performed after 2hours (16.7minutes; 95% CI, -14.3 to 29.9). Propensity score models using machine learning-selected variables yielded similar results. CONCLUSION: Performance of POC ultrasonography likely improves time to disposition when performed early on ED patients with shock.

Increased Sensitivity of Focused Cardiac Ultrasound for Pulmonary Embolism in Emergency Department Patients With Abnormal Vital Signs.

BACKGROUND: Focused cardiac ultrasound (FOCUS) is insensitive for pulmonary embolism (PE). Theoretically, when a clot is large enough to cause vital sign abnormalities, it is more likely to show signs of right ventricular dysfunction on FOCUS, although this has not been well quantified. A rapid bedside test that could quickly and reliably exclude PE in patients with abnormal vital signs could be of high utility in emergency department (ED) patients. We hypothesized that in patients with tachycardia or hypotension, the sensitivity of FOCUS for PE would increase substantially. METHODS: We performed a prospective observational multicenter cohort study involving a convenience sample of patients from six urban academic EDs. Patients suspected to have PE with tachycardia (heart rate [HR] ≥ 100 beats/min) or hypotension (systolic blood pressure [sBP] < 90 mm Hg) underwent FOCUS before computed tomography angiography (CTA). FOCUS included assessment for right ventricular dilation, McConnell's sign, septal flattening, tricuspid regurgitation, and tricuspid annular plane systolic excursion. If any of these were abnormal, FOCUS was considered positive, while if all were normal, FOCUS was considered negative. We a priori planned a subgroup analysis of all patients with a HR ≥ 110 beats/min (regardless of their sBP). We then determined the diagnostic test characteristics of FOCUS for PE in the entire patient population and in the predefined subgroup, based on CTA as the criterion standard. Inter-rater reliability of FOCUS was determined by blinded review of images by an emergency physician with fellowship training in ultrasound. RESULTS: A total of 143 subjects were assessed for enrollment and 136 were enrolled; four were excluded because they were non-English-speaking and three because of inability to obtain any FOCUS windows. The mean (±SD) age of enrolled subjects was 56 (±7) years, mean (±SD) HR was 114 (±12) beats/min, and 37 (27.2%) subjects were diagnosed with PE on CTA. In all subjects, FOCUS was 92% (95% confidence interval [CI] = 78% to 98%) sensitive and 64% specific (95% CI = 53% to 73%) for PE. In the subgroup of 98 subjects with a HR ≥ 110 beats/min, FOCUS was 100% sensitive (95% CI = 88% to 100%) and 63% specific (95% CI = 51% to 74%) for PE. There was substantial interobserver agreement for FOCUS (κ = 1.0, 95% CI = 0.31 to 1.0). CONCLUSIONS: A negative FOCUS examination may significantly lower the likelihood of the diagnosis of PE in most patients who are suspected of PE and have abnormal vital signs. This was especially true in those patients with a HR ≥ 110 beats/min. Our results suggest that FOCUS can be an important tool in the initial evaluation of ED patients with suspected PE and abnormal vital signs.

Screening for abdominal aortic aneurysm in asymptomatic at-risk patients using emergency ultrasound.

OBJECTIVE: Abdominal aortic aneurysm (AAA) is a deadly but often clinically silent disease. Patients at increased risk are elderly men with risk factors for vascular disease who may not have adequate screening through primary care. We sought to examine the prevalence and feasibility of screening for AAA in at-risk patients presenting for unrelated complaints using emergency physician-performed bedside ultrasound. METHODS: At-risk patients presenting with unrelated complaints were screened for AAA by emergency physician-performed ultrasound. Scan was rated as complete, limited, or inadequate, and time to complete scan noted. Patients with identified AAA were provided with appropriate follow-up and were followed to look at confirmatory imaging and clinical course. RESULTS: A total of 179 patients were screened, with 12 AAAs discovered (6.7%; 95% confidence interval, 3.9%-11.4%). Average time to perform the screening ultrasound was 141 +/- 135 seconds. Average discrepancy between emergency ultrasound and formal imaging was 3.9 mm. Of 12 (92%) patients, 11 were followed up, with repair recommended in 3 patients. CONCLUSION: The emergency department represents a potential opportunity for screening at-risk patients for AAA. Emergency ultrasound is a fast and accurate method for identifying patients with AAA who may benefit from follow-up or intervention.

The Practice and Implications of Finding Fluid During Point-of-Care Ultrasonography: A Review.

Importance: Point-of-care ultrasonography (POCUS) is an increasingly affordable and portable technology that is an important part of 21st-century medicine. When appropriately used, POCUS has the potential to expedite diagnosis and improve procedural success and safety. POCUS is now being adopted in medical education as early as the first year of medical school. While potentially powerful and versatile, POCUS is a user-dependent technology that has not been formalized or standardized yet within internal medicine residency training programs. Physicians and residency directors are trying to determine whether to incorporate POCUS, and if so, how. In this systematic review, basic concepts and applications of POCUS are examined, as are issues surrounding training and implementation. Observations: A key use of POCUS is to detect fluid, and this is a cornerstone of POCUS teaching. Even in inexperienced hands, POCUS has shown to be more sensitive and specific than physical examination for conditions such as ascites, pleural effusion, and pericardial effusion. Detecting fluid requires a basic understanding of ultrasonography operation, sonographic anatomy, and probe orientation. Once fluid is localized, ultrasonographic guidance can increase success and decrease complications of common procedures such as thoracentesis or paracentesis. Conclusions and Relevance: POCUS can augment physical examination and procedural efficacy but requires appropriate education and program setup. As POCUS continues to spread, internal medicine physicians need to clarify how they intend to use this technology. Equipment is now increasingly accessible, but programs need to determine how to allocate time and resources to training, clinical use, and quality assurance. Programs that develop robust implementation processes that establish proper scope of practice and include quality assurance that use image archival and feedback can ensure POCUS will positively impact patient care across hospital systems.

Cost-effectiveness of the Cardiac Component of the Focused Assessment of Sonography in Trauma Examination in Blunt Trauma.

BACKGROUND: Blunt cardiac injury severe enough to require surgical intervention (sBCI) is an exceedingly rare event occurring in approximately 1 out of every 1600 trauma patients. While performing the cardiac component of the Focused Assessment of Sonography in Trauma (cFAST) exam is effective in penetrating trauma, it is unclear whether it is of value in blunt trauma given the low prevalence of sBCI, the imperfect test characteristics of the FAST exam, and the rate of incidental pericardial effusion. OBJECTIVE: The objective was to determine through decision analysis whether performing the cFAST exam is cost-effective in the evaluation of hypotensive and normotensive blunt trauma patients. METHODS: We created two decision analytic models using commercially available software (TreeAgePro2011) to evaluate the cost-effectiveness of the cFAST in hypotensive (systolic blood pressure <90 mm Hg) and normotensive blunt trauma patients. Clinical probabilities were obtained from published data. Costs were estimated from Medicare reimbursement and charge data. The willingness-to-pay threshold was $50,000/quality-adjusted life-years (QALYs). Sensitivity analyses were performed over plausible ranges using available literature. RESULTS: In hypotensive patients, for the base case scenario of a 34-year-old with blunt trauma, the cFAST strategy had a cost of $42,882.70 and an effectiveness of 25.3597 QALYs, whereas the no cFAST strategy had a cost of $42,753.52 and an effectiveness of 25.3532 QALYs. The incremental cost-effectiveness ratio (ICER) was $19,918/QALY. For normotensive patients the cFAST strategy had a cost of $18,331.03 and an effectiveness of 23.2817 QALYs, whereas the no cFAST strategy had a cost of $18,207.58 and an effectiveness of 23.2814 QALYs. The ICER was $465,867/QALY. In the sensitivity analyses, age, probability of death from sBCI with prompt treatment, and probability of sBCI were the main drivers of variability in the model outcomes. CONCLUSIONS: The cFAST for blunt trauma is cost-effective for hypotensive but not for normotensive patients. The ICER for hypotensive patients was more than 20 times higher than the ICER for normotensive patients. Our results suggest that performing the cFAST exam may not be an effective use of resources in normotensive blunt trauma patients.

The "5Es" of emergency physician-performed focused cardiac ultrasound: a protocol for rapid identification of effusion, ejection, equality, exit, and entrance.

Emergency physician (EP)-performed focused cardiac ultrasound (EP FOCUS) has been increasingly recognized as a crucial tool to help clinicians diagnose and treat potentially life-threatening conditions. The existing literature demonstrates a variety of EP FOCUS applications and protocols; however, EP FOCUS is not taught, practiced, or interpreted consistently between institutions. Drawing on over 12 years of experience in a large-volume, high-acuity academic emergency department, we have developed a protocol for teaching and performing EP FOCUS known as "The 5Es," where each E represents a specific assessment for immediately relevant clinical information. These include pericardial effusion, qualitative left ventricular ejection, ventricular equality, exit (aortic root diameter), and entrance (inferior vena cava diameter and respirophasic variation). Each of these assessments has been well described in the emergency medicine literature and is within the scope of EP-performed echocardiography. This approach provides a reliable and easily recalled framework for assessing, teaching, and communicating EP FOCUS findings that are essential in caring for the patient in the emergency setting.

Prevalence and clinical importance of alternative causes of symptoms using a renal colic computed tomography protocol in patients with flank or back pain and absence of pyuria.

OBJECTIVES: The study was undertaken to determine the prevalence and clinical importance of alternative causes of symptoms discovered in patients undergoing flank pain protocol (FPP) computed tomography (CT) scans in patients with classic symptoms of kidney stone (flank pain, back pain, or both) without evidence of urine infection. METHODS: This was a retrospective observational analysis of all adult patients undergoing FPP CT scans at two emergency departments (EDs) between April 2005 and November 2010. All CTs (N = 5,383) were reviewed and categorized as "no cause of symptoms seen on CT," "ureteral stone as cause of symptoms," or "non-kidney stone cause of symptoms." Non-kidney stone scans were further categorized as "acutely important," "follow-up recommended," or "unimportant cause," based on a priori diagnostic classifications. All nonstone causes of pain and a random subset of subjects (n = 1,843; 34%) underwent full record review blinded to CT categorization to determine demographics, whether flank and/or back pain was present, and whether there was objective evidence of pyuria. RESULTS: Of all FPP CT scans during the study period, a ureteral stone was found to cause symptoms in 47.7% of CTs, with no cause of symptoms found in 43.3% of CTs. A non-kidney stone diagnosis was found in 9.0% of all CTs, with 6.1% being categorized as "acutely important," 2.2% as "follow-up recommended," and 0.65% with symptoms from an "unimportant cause." In the randomly selected subset undergoing full record review, categorizations were similar, with 49.0% of CTs showing kidney stone as cause of pain and 9.0% a non-kidney stone cause (5.9% "acutely important"). When subjects with evidence of urine infection or without flank or back pain were excluded, ureteral stone was identified as the cause of pain in 54.9% of CTs, while non-kidney stone cause of symptoms was found in 5.4% of scans and acutely important alternate causes in 2.8% of scans. CONCLUSIONS: While a non-kidney stone cause for a patient's symptoms are found in nearly 10% of CTs done using a FPP, acutely important findings occur in less than 3% of scans done in patients with flank or back pain and absence of pyuria.