Diagnosing centrally located pulmonary embolisms in the emergency department using point-of-care ultrasound.

OBJECTIVE: The study objective was to investigate the combined accuracy of right heart strain on focused cardiac ultrasound (FOCUS) and deep vein thrombosis (DVT) on compression ultrasound (CUS) for identification of centrally located pulmonary embolism (PE) diagnosed on computed tomography pulmonary angiography (CTPA). METHODS: This was a prospective observational study using a convenience sample of patients undergoing CTPA in the emergency department (ED) for evaluation of PE. Patients received a FOCUS looking for right heart strain (McConnell's sign, septal flattening, right ventricular enlargement or tricuspid annular plane systolic ejection (TAPSE) <17mm) and a CUS looking for DVT. Ultrasounds were interpreted by both the investigator performing the ultrasound and the principal investigator independently. RESULTS: There were 199 patients enrolled in the study, with 46/199 (23.1%) positive for a PE. Of these, 20/46 (43.5%) PE's were located centrally. Of those with a PE, 20/46 (43.5%) had an associated DVT identified on bedside ultrasound. Among patients with a proximal PE, 18/20 (90.0%) had evidence of right heart strain and the combination of lower extremity CUS and FOCUS was 100% sensitive. Diagnostic accuracy of ultrasound was much lower for peripherally located PEs. CONCLUSIONS: Emergency physician-performed bedside ultrasound may be sufficient to exclude the presence of centrally located PE, as the sensitivity in this study was 100%. Additionally, several patients with PE may qualify for early anticoagulation when DVT is identified, and further research in indicated to determine whether these patients ultimately require CTPA given identical treatment algorithms in the absence of RV strain or biomarker elevation.

A Comparison of Web-Based with Traditional Classroom-Based Training of Lung Ultrasound for the Exclusion of Pneumothorax.

BACKGROUND: Lung ultrasound (LUS) is a well-established method that can exclude pneumothorax by demonstration of pleural sliding and the associated ultrasound artifacts. The positive diagnosis of pneumothorax is more difficult to obtain and relies on detection of the edge of a pneumothorax, called the "lung point." Yet, anesthesiologists are not widely taught these techniques, even though their patients are susceptible to pneumothorax either through trauma or as a result of central line placement or regional anesthesia techniques performed near the thorax. In anticipation of an increased training demand for LUS, efficient and scalable teaching methods should be developed. In this study, we compared the improvement in LUS skills after either Web-based or classroom-based training. We hypothesized that Web-based training would not be inferior to "traditional" classroom-based training beyond a noninferiority limit of 10% and that both would be superior to no training. Furthermore, we hypothesized that this short training session would lead to LUS skills that are similar to those of ultrasound-trained emergency medicine (EM) physicians. METHODS: After a pretest, anesthesiologists from 4 academic teaching hospitals were randomized to Web-based (group Web), classroom-based (group class), or no training (group control) and then completed a posttest. Groups Web and class returned for a retention test 4 weeks later. All 3 tests were similar, testing both practical and theoretical knowledge. EM physicians (group EM) performed the pretest only. Teaching for group class consisted of a standardized PowerPoint lecture conforming to the Consensus Conference on LUS followed by hands-on training. Group Web received a narrated video of the same PowerPoint presentation, followed by an online demonstration of LUS that also instructs the viewer to perform an LUS on himself using a clinically available ultrasound machine and submit smartphone snapshots of the resulting images as part of a portfolio system. Group Web received no other hands-on training. RESULTS: Groups Web, class, control, and EM contained 59, 59, 20, and 42 subjects. After training, overall test results of groups Web and class improved by a mean of 42.9% (±18.1% SD) and 39.2% (±19.2% SD), whereas the score of group control did not improve significantly. The test improvement of group Web was not inferior to group class. The posttest scores of groups Web and class were not significantly different from group EM. In comparison with the posttests, the retention test scores did not change significantly in either group. CONCLUSIONS: When training anesthesiologists to perform LUS for the exclusion of pneumothorax, we found that Web-based training was not inferior to traditional classroom-based training and was effective, leading to test scores that were similar to a group of clinicians experienced in LUS.

Evaluation of the Aortic Arch from the Suprasternal Notch View Using Focused Cardiac Ultrasound.

BACKGROUND: The suprasternal notch view (SSNV) is an additional echocardiographic view not routinely used by emergency physicians (EPs) performing focused cardiac ultrasound (FOCUS). OBJECTIVE: This pilot study determined the ease and self-perceived accuracy of the SSNV as performed by EPs. Additionally, we assessed the accuracy of FOCUS including the SSNV in thoracic aortic measurements compared to chest CT angiography (CTA). METHODS: This was a prospective, observational, pilot study of adult patients undergoing chest CTA. Thoracic aortic measurements were recorded at the sinus of Valsalva, sinotubular junction, and ascending aorta at its widest diameter in the parasternal long axis (PSL) view and SSNV. EPs rated ease of acquisition and self-perceived accuracy of thoracic aorta measurements. Two blinded radiologists performed thoracic aortic CTA measurements at predefined locations corresponding to the ultrasound measurements. RESULTS: Of the 79 patients (median age 57 years) enrolled, the SSNV was obtained in 97% of cases. EPs rated the ease of obtaining the SSNV as "easy" in 64.5% of cases and "very difficult" in 7.6% of cases. The mean difference between ultrasound (FOCUS plus SSNV) and CTA measurements were 1.2 mm (95% limits of agreement -2.9 to 5.3) at the sinus of Valsalva, 1.0 mm (95% limits of agreement -5.5 to 3.6 mm) at the sinotubular junction, 0.8 mm (95% limits of agreement -6.2 to 4.6 mm) at the proximal ascending aorta, and 0.6 mm (95% limits of agreement -2.8 to 4.0) at the aortic arch. CONCLUSIONS: Our findings suggest that the SSNV is an easily attainable and accurate view of the thoracic aorta that can be obtained by EPs in the majority of ED patients.

Double-lung point sign in traumatic pneumothorax.

Lung ultrasound has emerged as a rapid and accurate screening tool for pneumothorax. The lung point sign, a sonographic representation of the point on the chest wall where the pleural layers re-adhere, is 100% specific to confirm the diagnosis. Double lung point sign for a single pneumothorax is extremely unusual and has only been reported twice in the literature. A 49-year-old woman was transported to the emergency department (ED) intubated and sedated with severe head injury. She remained hemodynamically stable without respiratory compromise throughout her ED course. Chest computed tomography was notable for an anterior left pneumothorax with underlying pulmonary contusion. Bedside ultrasound of this region revealed a double lung point sign. Our case report is the first to confirm association of the double lung point sign with a single pneumothorax on corresponding computed tomographic imaging.

Positive FAST without hemoperitoneum due to fluid resuscitation in blunt trauma.

BACKGROUND: The focused assessment with sonography in trauma (FAST) examination is an important screening tool in the evaluation of blunt trauma patients. OBJECTIVES: To describe a case of a hemodynamically unstable polytrauma patient with positive FAST due to fluid resuscitation after blunt trauma. CASE REPORT: We describe a case of a hemodynamically unstable polytrauma patient who underwent massive volume resuscitation prior to transfer from a community hospital to a trauma center. On arrival at the receiving institution, the FAST examination was positive for free intraperitoneal fluid, but no hemoperitoneum or significant intra-abdominal injuries were found during laparotomy. In this case, it is postulated that transudative intraperitoneal fluid secondary to massive volume resuscitation resulted in a positive FAST examination. CONCLUSION: This case highlights potential issues specific to resuscitated trauma patients with prolonged transport times. Further study is likely needed to assess what changes, if any, should be made in algorithms to address the effect of prior resuscitative efforts on the test characteristics of the FAST examination.

Effective analgesia with low-dose ketamine and reduced dose hydromorphone in ED patients with severe pain.

OBJECTIVE: We assessed the analgesic effect and feasibility of low-dose ketamine combined with a reduced dose of hydromorphone for emergency department (ED) patients with severe pain. METHODS: This was a prospective observational study of adult patients with severe pain at an urban public hospital. We administered 0.5 mg of intravenous (IV) hydromorphone and 15 mg of IV ketamine, followed by optional 1 mg hydromorphone IV at 15 and 30 minutes. Pain intensity was assessed at 12 intervals over 120 minutes using a 10-point verbal numerical rating scale (NRS). Patients were monitored throughout for adverse events. Dissociative side effects were assessed using the side effects rating scale for dissociative anesthetics. RESULTS: Of 30 prospectively enrolled patients with severe pain (initial mean NRS, 9), 14 reported complete pain relief (NRS, 0) at 5 minutes; the mean reduction in NRS pain score was 6.0 (SD, 3.2). At 15 minutes, the mean reduction in NRS pain score was 5.0 (SD, 2.8). The summed pain intensity difference and percent summed pain intensity difference scores were 25 (95% confidence interval [CI], 21-30) and 58% (95% CI, 49-68) at 30 minutes and 41 (95% CI, 34-48) and 50% (95% CI, 42-58) at 60 minutes, respectively. Most patients (80%) reported only weak or modest side effects. Ninety percent of patients reported that they would have the medications again. No significant adverse events occurred. CONCLUSIONS: Low-dose ketamine combined with a reduced dose hydromorphone protocol produced rapid, profound pain relief without significant side effects in a diverse cohort of ED patients with acute pain.

A pilot retrospective study of a physician-directed and genomics-based model for precision lifestyle medicine.

Precision lifestyle medicine is a relatively new field in primary care, based on the hypothesis that genetic predispositions influence an individual's response to specific interventions such as diet, exercise, and prescription medications. Despite the increase in commercially available genomic testing, few studies have investigated effects of a physician-directed program to optimize chronic disease using genomics-based precision medicine. We performed an pilot, observational cohort study to evaluate effects of the Wild Health program, a physician and health coach service offering genomics-based lifestyle and medical interventions, on biomarkers indicative of chronic disease. 871 patients underwent genomic testing, biomarker testing, and ongoing health coaching after initial medical consultation by a physician. Improvements in several clinically relevant out-of-range biomarkers at baseline were identified in a large proportion of patients treated through lifestyle intervention without the use of prescription medication. Notably, normalization of several biomarkers associated with chronic disease occurred in 47.5% (hemoglobin A1c [HbA1c]), 33.3% (low density lipoprotein particle number [LDL-P]), and 33.2% (C-reactive protein [CRP]). However, due to the inherent limitations of our observational study design and use of retrospective data, ongoing work will be crucial for continuing to shed light on the effectiveness of physician-led, genomics-based lifestyle coaching programs. Future studies would benefit from implementing a randomized controlled study design, tracking specific interventions, and evaluating physiological data, such as BMI.

Ultrasound-guided abdominal wall nerve blocks in the ED.

INTRODUCTION: The anterolateral abdominal wall is innervated by the T7 to L1 anterior rami, whose nerves travel in the fascial plane between the internal oblique and transversus abdominus muscles, known as the transversus abdominus plane (TAP). Ultrasound-guided techniques of regional anesthesia that target the TAP are increasingly relied upon by anesthesiologists for pain management related to major abdominal and gynecologic surgeries. Our objective was to explore the potential utility of these techniques to provide anesthesia for abdominal wall procedures in the emergency department (ED). METHODS: We conducted a prospective, cross-sectional, descriptive case series of ultrasound-guided abdominal wall nerve blocks performed by emergency physicians in the ED. RESULTS: Between July 1 and September 1, 2010, 4 patients were selected for an ultrasound-guided TAP nerve block or an ilioinguinal/iliohypogastric nerve block. Three patients presented with soft tissue abscesses on the anterior abdomen, and 1 patient presented with postoperative pain and swelling after hernia surgery. Patients were aged 35 to 50 years. Mean time to complete the procedures was 8.5 minutes. All blocks resulted in complete surgical anesthesia sufficient for comfortable incision and drainage or needle aspiration without the need for additional analgesia or sedation. There were no complications. CONCLUSIONS: In a series of 4 ED patients, ultrasound-guided TAP and ilioinguinal/iliohypogastric blocks performed by emergency physicians provided excellent procedural anesthesia. Further study of these techniques as an alternative to sedation for ED patients undergoing abdominal wall procedures is warranted.

The ultrasound-guided superficial cervical plexus block for anesthesia and analgesia in emergency care settings.

The ultrasound-guided superficial cervical plexus (SCP) block may be useful for providers in emergency care settings who care for patients with injuries to the ear, neck, and clavicular region, including clavicle fractures and acromioclavicular dislocations. The SCP originates from the anterior rami of the C1-C4 spinal nerves and gives rise to 4 terminal branches--greater auricular, lesser occipital, transverse cervical, and suprascapular nerves--that provide sensory innervation to the skin and superficial structures of the anterolateral neck and sections of the ear and shoulder. Here we describe an ultrasound-guided technique for blockade of the SCP that is potentially well suited to emergency care settings. We present the first case description of its successful use to manage pain for a patient with an acute clavicle fracture. This case is presented to highlight one of several potential applications of this promising new technique in the emergency department.

Emergency ultrasound diagnosis of deep venous thrombosis in the pediatric emergency department: a case series.

The diagnosis of deep venous thrombosis (DVT) in patients presenting to the emergency department (ED) has traditionally been limited to examinations by radiologists and ultrasound technicians. Although contrast venography is considered the criterion standard for diagnosis of DVT, time, personnel, cost, exposure to radiation, and the invasive nature of the study (need for venous access) potentially limit the ability to perform the study in an emergent setting. Ultrasonography is an alternative method for thrombus detection and is widely preferred. However, in many health care settings, consultative ultrasound services may not be available immediately, especially after hours and on weekends. Based on recent studies demonstrating accuracy in adult patients, emergency sonographic evaluation of DVT by emergency physicians is considered a core emergency ultrasound application and is recently recommended as standard training to all emergency medicine residents. The diagnosis of DVT in children by emergency ultrasound in the pediatric ED has not been previously described. We present 3 cases of DVT in adolescents identified by emergency ultrasound evaluation in the pediatric ED.

Ultrasound identification of traumatic pneumobilia.

A 65-year-old woman presented to the emergency department with low back pain after being hit by a truck at low speed. Although her abdominal examination showed benign results, an extended Focused Assessment With Sonography in Trauma ultrasound examination was performed and incidentally demonstrated evidence of pneumobilia. There were no additional intra-abdominal injuries noted. Subsequent computed tomography and magnetic resonance cholangiopancreatography confirmed these findings. The etiology of traumatic pneumobilia is discussed with a brief review of the literature on the subject.

Needle tip visualization during ultrasound-guided vascular access: short-axis vs long-axis approach.

OBJECTIVES: Ultrasound guidance for central venous catheterization improves success rates and decreases complications when compared to the landmark technique. Prior research has demonstrated that arterial and/or posterior vein wall puncture still occurs despite real-time ultrasound guidance. The inability to maintain visualization of the needle tip may contribute to these complications. This study aims to identify whether long-axis or short-axis approaches to ultrasound-guided vascular access afford improved visibility of the needle tip. METHODS: A prospective trial was conducted at a level I trauma center with an emergency medicine residency. Medical students and residents placed needles into vascular access tissue phantoms using long-axis and short-axis approaches. Ultrasound images obtained at the time of vessel puncture were then reviewed. Primary outcome measures were visibility of the needle tip at the time of puncture and total time to successful puncture of the vessel. RESULTS: All subjects were able to successfully obtain simulated blood from the tissue phantom. Mean time to puncture was 14.8 seconds in the long-axis group and 12.4 seconds in the short-axis group (P = .48). Needle tip visibility at the time of vessel puncture was higher in the long-axis group (24/39, 62%) as opposed to the short-axis group (9/39, 23%) (P = .01). CONCLUSIONS: In a simulated vascular access model, the long-axis approach to ultrasound-guided vascular access was associated with improved visibility of the needle tip during vessel puncture. This approach may help decrease complications associated with ultrasound-guided central venous catheterization and should be prospectively evaluated in future studies.

Ultrasound detection of guidewire position during central venous catheterization.

INTRODUCTION: Ultrasound guidance decreases complications of central venous catheter (CVC) placement, but risks of arterial puncture and inadvertent arterial catheter placement exist. Ultrasound-assisted detection of guidewire position in the internal jugular vein could predict correct catheter position before dilation and catheter placement. METHODS: Ultrasound examinations were performed in an attempt to identify the guidewire before dilation and catheter insertion in 20 adult patients requiring CVC placement. Central venous pressures were measured after completion of the procedure. RESULTS: Guidewires were visible within the lumen of the internal jugular vein in all subjects. Central venous pressures confirmed venous placement of catheters. Ultrasound visualization of the guidewire predicted venous CVC placement with 100% sensitivity (95% confidence interval 80-100%) and 100% specificity (95% confidence interval 80%-100%). CONCLUSIONS: Ultrasound reliably detects the guidewire during CVC placement and visualization of the wire before dilation and catheter insertion may provide an additional measure of safety during ultrasound-guided CVC placement.

Ultrasound diagnosis of papilledema and increased intracranial pressure in pseudotumor cerebri.

Bedside ultrasound has been used to identify intracranial hypertension through the measurement of optic nerve sheath diameter. This case report describes the sonographic detection of papilledema and a wide optic nerve sheath in a patient with pseudotumor cerebri who presented to the Emergency Department with headache and photophobia, and in whom fundoscopy was poorly tolerated. Bedside ultrasound may represent an alternate means of assessing for papilledema when a traditional fundoscopic exam is non-diagnostic.

Bedside ultrasound diagnosis of pulmonary contusion.

A 10-year-old boy presented to the emergency department after being struck by a van while crossing the street. He complained of right side chest pain, and a chest radiography was suggestive of pulmonary contusion. The treating physician performed a bedside ultrasound that revealed a right-sided pulmonary contusion that was subsequently confirmed on computed tomography of the thorax. The sonographic features of pulmonary contusion are described, and the possible role of lung sonography in the assessment of pediatric thoracic trauma is discussed.

Bilateral femoral artery aneurysms and bilateral common femoral vein thromboses.

We report the sonographic findings of a patient with bilateral femoral artery aneurysms with concomitant bilateral deep venous thrombosis of the common femoral veins. Femoral arterial aneurysms may be associated with additional arterial aneurysms, and rarely with associated venous thrombosis. Patients presenting with femoral artery aneurysms should undergo a thorough vascular sonographic examination that includes the abdominal aorta, the iliac vessels and the deep venous system of the lower extremity.

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.