Michael Mallin

Ultrasonography versus Computed Tomography for Suspected Nephrolithiasis

BACKGROUND There is a lack of consensus about whether the initial imaging method for patients with suspected nephrolithiasis should be computed tomography (CT) or ultrasonography. METHODS In this multicenter, pragmatic, comparative effectiveness trial, we randomly assigned patients 18 to 76 years of age who presented to the emergency department with suspected nephrolithiasis to undergo initial diagnostic ultrasonography performed by an emergency physician (point-of-care ultrasonography), ultrasonography performed by a radiologist (radiology ultrasonography), or abdominal CT. Subsequent management, including additional imaging, was at the discretion of the physician. We compared the three groups with respect to the 30-day incidence of high-risk diagnoses with complications that could be related to missed or delayed diagnosis and the 6-month cumulative radiation exposure. Secondary outcomes were serious adverse events, related serious adverse events (deemed attributable to study participation), pain (assessed on an 11-point visual-analogue scale, with higher scores indicating more severe pain), return emergency department visits, hospitalizations, and diagnostic accuracy. RESULTS A total of 2759 patients underwent randomization: 908 to point-of-care ultrasonography, 893 to radiology ultrasonography, and 958 to CT. The incidence of high-risk diagnoses with complications in the first 30 days was low (0.4%) and did not vary according to imaging method. The mean 6-month cumulative radiation exposure was significantly lower in the ultrasonography groups than in the CT group (P<0.001). Serious adverse events occurred in 12.4% of the patients assigned to point-of-care ultrasonography, 10.8% of those assigned to radiology ultrasonography, and 11.2% of those assigned to CT (P=0.50). Related adverse events were infrequent (incidence, 0.4%) and similar across groups. By 7 days, the average pain score was 2.0 in each group (P=0.84). Return emergency department visits, hospitalizations, and diagnostic accuracy did not differ significantly among the groups. CONCLUSIONS Initial ultrasonography was associated with lower cumulative radiation exposure than initial CT, without significant differences in high-risk diagnoses with complications, serious adverse events, pain scores, return emergency department visits, or hospitalizations. (Funded by the Agency for Healthcare Research and Quality.).

First “Glass” Education: Telementored Cardiac Ultrasonography Using Google Glass- A Pilot Study

OBJECTIVES The objective of this study was to determine the feasibility of telementored instruction in bedside ultrasonography (US) using Google Glass. The authors sought to examine whether first-time US users could obtain adequate parasternal long axis (PSLA) views to approximate ejection fraction (EF) using Google Glass telementoring. METHODS This was a prospective, randomized, single-blinded study. Eighteen second-year medical students were randomized into three groups and tasked with obtaining PSLA cardiac imaging. Group A received real-time telementored education through Google Glass via Google Hangout from a remotely located expert. Group B received bedside education from the same expert. Group C represented the control and received no instruction. Each subject was given 3 minutes to obtain a best PSLA cardiac imaging using a portable GE Vscan. Image clips obtained by each subject were stored. A second expert, blinded to instructional mode, evaluated images for adequacy and assigned an image quality rating on a 0 to 10 scale. RESULTS Group A was able to obtain adequate images six out of six times (100%) with a median image quality rating of 7.5 (interquartile range [IQR] = 6 to 10) out of 10. Group B was also able to obtain adequate views six out of six times (100%), with a median image quality rating of 8 (IQR = 7 to 9). Group C was able to obtain adequate views one out of six times (17%), with a median image quality of 0 (IQR = 0 to 2). There were no statistically significant differences between Group A and Group B in the achievement of adequate images for E-point septal separation measurement or in image quality. CONCLUSIONS In this pilot/feasibility study, novice US users were able to obtain adequate imaging to determine a healthy patients EF through telementored education using Google Glass. These preliminary data suggest telementoring as an adequate means of medical education in bedside US. This conclusion will need to be validated with larger, more powerful studies including evaluation of pathologic findings and varying body habitus among models.

Diagnosis of appendicitis by bedside ultrasound in the ED

BACKGROUND Computed tomography (CT) has largely become standard of care for diagnosing appendicitis at the expense of increased patient radiation exposure, cost, and time to surgical intervention. To date, there are very limited data on the accuracy of bedside ultrasound (BUS) for the diagnosis of appendicitis in adults. OBJECTIVE The objective of this study is to evaluate test characteristics of BUS for diagnosis of acute appendicitis in the emergency department. METHODS Data were prospectively collected on 97 cases of suspected appendicitis, which had BUS performed by trained residents with attending supervision between August 2011 and November 2013. All BUS interpretation and additional diagnostic imaging were left to the discretion of the physician or surgical consultants. A blinded ultrasound fellowship-trained physician reviewed all images after clinical treatment. Bedside ultrasound findings and patient outcomes were reported. RESULTS A total of 97 adult cases underwent diagnostic ultrasound scans for suspected appendicitis. Of 97 cases, 34 had acute appendicitis by surgery/pathology report. Twenty-four BUS were positive for acute appendicitis and 11 were nondiagnostic. Of 24 positive ultrasounds, 23 had appendicitis on pathology report. There was 1 false-positive result, yielding a sensitivity of 67.65% (95% confidence limits, 49.5%-82.6%) and a specificity of 98.41% (95% confidence limits, 91.4%-99.7%). Of 23 positive BUS, 12 cases went to the Operating Room without an abdominal CT yielding a 12% reduction in CT utilization. If all positive BUS went to the OR without a CT scan, this would yield a 24% reduction in CT utilization. CONCLUSIONS Bedside ultrasound may be an appropriate initial test to evaluate patients with suspected acute appendicitis in the emergency department.

Practice characteristics of Emergency Department extracorporeal cardiopulmonary resuscitation (eCPR) programs in the United States: The current state of the art of Emergency Department extracorporeal membrane oxygenation (ED ECMO).

PURPOSE To characterize the current scope and practices of centers performing extracorporeal cardiopulmonary resuscitation (eCPR) on the undifferentiated patient with cardiac arrest in the emergency department. METHODS We contacted all US centers in January 2016 that had submitted adult eCPR cases to the Extracorporeal Life Support Organization (ELSO) registry and surveyed them, querying for programs that had performed eCPR in the Emergency Department (ED ECMO). Our objective was to characterize the following domains of ED ECMO practice: program characteristics, patient selection, devices and techniques, and personnel. RESULTS Among 99 centers queried, 70 responded. Among these, 36 centers performed ED ECMO. Nearly 93% of programs are based at academic/teaching hospitals. 65% of programs are less than 5 years old, and 60% of programs perform ≤3 cases per year. Most programs (90%) had inpatient eCPR or salvage ECMO programs prior to starting ED ECMO programs. The majority of programs do not have formal inclusion and exclusion criteria. Most programs preferentially obtain vascular access via the percutaneous route (70%) and many (40%) use mechanical CPR during cannulation. The most commonly used console is the Maquet Rotaflow(®). Cannulation is most often performed by cardiothoracic (CT) surgery, and nearly all programs (>85%) involve CT surgeons, perfusionists, and pharmacists. CONCLUSIONS Over a third of centers that submitted adult eCPR cases to ELSO have performed ED ECMO. These programs are largely based at academic hospitals, new, and have low volumes. They do not have many formal inclusion or exclusion criteria, and devices and techniques are variable.

Utility of the Emergency Department Observation Unit in Ensuring Stress Testing in Low-Risk Chest Pain Patients

BACKGROUND Recent research has noted low rates of compliance among ED chest pain patients referred for outpatient stress testing. The practice at our institution, a 39,000 visits per year emergency department (ED), is to place chest pain patients considered low risk for acute coronary syndrome in an observation unit for serial biomarker testing and provocative cardiac testing. Our objective was to determine the rates of positive stress tests among this group and to extrapolate from this the potential missed positive stress tests if these patients were referred instead for outpatient stress testing. METHODS This was a retrospective chart review of all chest pain patients admitted to the ED observation unit between April 2006 and June 2007. Baseline information, including a history of coronary disease, was recorded. Patients underwent a treadmill stress test, nuclear stress test, or coronary CT scan at the discretion of the attending emergency physician and/or the consulting cardiologist. Rates of positive stress test or coronary CT and patient disposition (admission to an inpatient unit versus discharge for outpatient follow-up) were noted. RESULTS A total of 353 patients underwent stress testing or coronary CT during the study period: 257 (72.8%) patients had an exercise treadmill echocardiogram, 61 (17.3%) patients underwent nuclear stress testing, and 35 (9.9%) patients had a coronary CT. Seventy patients (19.8%) had a history of coronary disease but had been considered appropriate for observation by the attending emergency physician. Thirty-nine stress tests were positive (11%) and 11 were indeterminate (3.1%). Among patients with no history of coronary disease, 20 stress tests were positive (7.1%), and 10 were indeterminate (3.5%). Of all patients with a positive stress test, 19 (48.7%) underwent cardiac catheterization and 1 (2.6%) had coronary artery bypass graft. Twenty-one of 39 patients with a positive stress test (54%) were ultimately admitted to an inpatient unit per the recommendation of the consulting cardiologist. Assuming a best-case scenario in which 70% of patients referred for outpatient stress testing actually have the testing done (based on a recent report of outpatient compliance), physicians would miss approximately 3.3% of patients with a positive stress test if these patients were discharged directly from the ED. CONCLUSION Among chest pain patients admitted to an ED observation unit, the rate of positive stress tests was 11%. Approximately 3.3% of patients with positive stress tests may have been missed if these patients were instead referred for outpatient testing.

GlideScope Versus Flexible Fiber Optic for Awake Upright Laryngoscopy

STUDY OBJECTIVES We compare laryngoscopic quality and time to highest-grade view between a face-to-face approach with the GlideScope and traditional flexible fiber-optic laryngoscopy in awake, upright volunteers. METHODS This was a prospective, randomized, crossover study in which we performed awake laryngoscopy under local anesthesia on 23 healthy volunteers, using both a GlideScope video laryngoscopy face-to-face technique with the blade held upside down and flexible fiber-optic laryngoscopy. Operator reports of Cormack-Lehane laryngoscopic views and video-reviewed time to highest-grade view, as well as number of attempts, were recorded. RESULTS Ten women and 13 men participated. A grade II or better view was obtained with GlideScope video laryngoscopy in 22 of 23 (95.6%) participants and in 23 of 23 (100%) participants with flexible fiber-optic laryngoscopy (relative risk GlideScope video laryngoscopy versus flexible fiber-optic laryngoscopy 0.96; 95% confidence interval 0.88 to 1.04). Median time to highest-grade view for GlideScope video laryngoscopy was 16 seconds (interquartile range 9 to 34) versus 51 seconds (interquartile range 35 to 96) for flexible fiber-optic laryngoscopy. A distribution of interindividual differences demonstrated that GlideScope video laryngoscopy was, on average, 39 seconds faster than flexible fiber-optic laryngoscopy (95% confidence interval 0.2 to 76.9 seconds). CONCLUSION GlideScope video laryngoscopy can be used to obtain a Cormack-Lehane grade II or better view in the majority of awake, healthy volunteers when an upright face-to-face approach is used and was slightly faster than traditional flexible fiber-optic laryngoscopy. However, flexible fiber-optic laryngoscopy may be more reliable at obtaining high-grade views of the larynx. Awake, face-to-face GlideScope use may offer an alternative approach to the difficulty airway, particularly among providers uncomfortable with flexible fiber-optic laryngoscopy.

Emergency physician–performed transesophageal echocardiography for extracorporeal life support vascular cannula placement☆

INTRODUCTION There is growing interest and application of extracorporeal membrane oxygenation (ECMO) as a life-saving procedure for out-of-hospital cardiac arrest (OHCA), also called extracorporeal life support (ECLS). Extracorporeal membrane oxygenation cannulation with ongoing chest compressions is challenging, and transesophageal echocardiography (TEE) is an invaluable tool with which to guide ECMO wire guidance and cannula positioning. METHODS We describe our protocol for TEE guidance by emergency physicians in our hospital. RESULTS Of our first 12 cases of ECLS, 10 have had TEE guidance by an emergency physician with successful placement and without complication or need for repositioning. Emergency physician-performed TEE for ECLS vascular cannula placement has been both feasible and useful in our experience and warrants further study.

Prospective evaluation of the use of the thrombolysis in myocardial infarction score as a risk stratification tool for chest pain patients admitted to an ED observation unit.

BACKGROUND The Thrombolysis in Myocardial Infarction (TIMI) score has shown use in predicting 30-day and 1-year outcomes in emergency department (ED) patients with potential acute coronary syndrome. Few studies have evaluated the TIMI score in risk stratifying patients selected for the ED observation Unit (EDOU). Risk stratification of patients in this group could identify those at risk for significant cardiac events. Our goal was to evaluate TIMI use for risk stratification in this population and compare outcomes among differing scores. METHODS A prospective observational study with 30-day telephone follow-up for a 12 month period. Baseline data, outcomes related to EDOU stay, admission, and 30-day outcomes were recorded. TIMI scores were calculated for each patient placed in EDOU. TIMI score was not utilized in the decision to place patients in observation. RESULTS N = 552. Composite outcomes recorded were myocardial infarction, revascularization, or death either during the EDOU stay, inpatient admission, or the 30-day follow-up. Eighteen composite outcomes were recorded: stent (12 patients), coronary artery bypass graft (3 patients), myocardial infarction and stent (2 patients), and myocardial infarction, and coronary artery bypass graft (1 patient). Distribution by TIMI score was: 0 (102 patients), 1 (196), 2 (142), 3 (72), 4 (27), and 5 (5). Risk of composite outcome increased by score: 0 (1%), 1 (2.6%), 2 (2.1%), 3 (6.9%), 4 (11.1%), and 5 (20%). Those with an intermediate risk score (3-5) were also more likely to require admission (15.4% vs 9.8%, P = .048). CONCLUSION The TIMI risk score may serve as an effective risk stratification tool among chest pain patients selected for EDOU placement. Patients with intermediate-risk by TIMI may be considered for inpatient admission and/or more aggressive evaluation and therapy.

Another WIN for Point-of-care Ultrasound: The Wire-in-needle Modified Seldinger Technique for Ultrasound-guided Central Venous Access

Dynamic ultrasound (US) guidance is an established practice standard for the placement of central venous catheters (CVCs) as it decreases mechanical complications and improves procedural success by both internal jugular and subclavian routes. However, despite clear advantages, complications of US-guided CVC placement still occur. Inadvertent arterial cannulation and posterior vessel wall puncture have been reported in both tissue phantom models and human subjects. As a result, real-time US visualization of the guidewire has been proposed as a means to confirm target vessel cannulation prior to dilation and CVC placement. In an effort to further improve patient safety and procedural success, we have developed the wire-in-needle (WIN) technique, a novel modification of the traditional Seldinger technique, wherein the introducer needle is “preloaded” with a guidewire prior to insertion through the skin. The needle is then advanced using an in-plane, long-axis technique until venous catheterization is visualized, after which the wire is advanced into the target vessel (Video Clip S1, available as supporting information in the online version of this paper). There are several advantages to this technique: 1. We find the manual dexterity associated with grasping the hub of the introducer needle to be far superior to grasping and simultaneously aspirating a syringe. 2. In the traditional approach, especially in patients with small-caliber vessels and significant respirophasic vessel diameters, we find that the needle tip is often dislodged from the target vessel when the syringe is detached prior to introducing the guidewire. In contrast, the WIN technique allows immediate placement of the guidewire in the target vessel after vessel penetration. 3. The preloaded introducer needle has a distinctly more visible US appearance (Figure 1), thus improving the operator’s ability to visualize the needle as it progresses toward the target vessel.

Transesophageal Echocardiography: Guidelines for Point-of-Care Applications in Cardiac Arrest Resuscitation

&NA; Cardiac arrest is one of the most challenging patient presentations managed by emergency care providers, and echocardiography can be instrumental in the diagnosis, prognosis, and treatment guidance in these critically ill patients. Transesophageal echocardiography has many advantages over transthoracic echocardiography in a cardiac arrest resuscitation. As transesophageal echocardiography is implemented more widely at the point of care during cardiac arrest resuscitations, guidelines are needed to assist emergency providers in acquiring the equipment and skills necessary to successfully incorporate it into the management of cardiac arrest victims.