Anthony J. Weekes

Comparison of Serial Qualitative and Quantitative Assessments of Caval Index and Left Ventricular Systolic Function During Early Fluid Resuscitation of Hypotensive Emergency Department Patients

OBJECTIVES The objective was to determine whether serial bedside visual estimates of left ventricular systolic function (LVF) and respiratory variation of the inferior vena cava (IVC) diameter would agree with quantitative measurements of LVF and caval index in hypotensive emergency department (ED) patients during fluid challenges. The authors hypothesized that there would be moderate inter-rater agreement on the visual estimates. METHODS This prospective observational study was performed at an urban, regional ED. Patients were eligible for enrollment if they were hypotensive in the ED as defined by a systolic blood pressure (sBP) of <100 mm Hg or mean arterial pressure of ≤65 mm Hg, exhibited signs or symptoms of shock, and the treating physician intended to administer intravenous (IV) fluid boluses for resuscitation. Sonologists performed a sequence of echocardiographic assessments at the beginning, during, and toward the end of fluid challenge. Both caval index and LVF were determined by the sonologist in qualitative then quantitative manners. Deidentified digital video clips of two-dimensional IVC and LVF assessments were later presented, in random order, to an ultrasound (US) fellowship-trained emergency physician using a standardized rating system for review. Statistical analysis included both descriptive statistics and correlation analysis. RESULTS Twenty-four patients were enrolled and yielded 72 caval index and LVF videos that were scored at the bedside prior to any measurements and then reviewed later. Visual estimates of caval index compared to measured caval index yielded a correlation of 0.81 (p < 0.0001). Visual estimates of LVF compared to fractional shortening yielded a correlation of 0.84 (p < 0.0001). Inter-rater agreement of respiratory variation of IVC diameter and LVF scores had simple kappa values of 0.70 (95% confidence interval [CI] = 0.56 to 0.85) and 0.46 (95% CI = 0.29 to 0.63), respectively. Significant differences in mean values between time 0 and time 2 were found for caval index measurements, the visual scores of IVC diameter variation, and both maximum and minimum IVC diameters. CONCLUSIONS This study showed that serial visual estimations of the respiratory variation of IVC diameter and LVF agreed with bedside measurements of caval index and LVF during early fluid challenges to symptomatic hypotensive ED patients. There was moderate inter-rater agreement in both visual estimates. In addition, acute volume loading was associated with detectable acute changes in IVC measurements.

Acute myocardial infarction caused by coronary embolism from infective endocarditis.

BACKGROUND Identifying an acute myocardial infarction caused by a non-atherosclerotic process can have consequences on the short- and long-term management of the disease. CASE REPORTS In the first case reported, a 39-year-old woman with a history of hypertension, diabetes, end-stage renal disease, deep vein thrombosis, and a recent hospitalization for staphylococcal bacteremia presented to the Emergency Department (ED) with acute onset of chest pain and shortness of breath. Her electrocardiogram (ECG) showed findings of an ST-segement elevation lateral wall acute myocardial infarction (AMI). The patients condition worsened in the ED, and thrombolytic therapy was initiated. The patient subsequently had a coronary catheterization that illustrated an irregular mitral valve and abrupt occlusions in the left anterior descending artery, suggestive of coronary embolism from a mitral valve source. This patient was later treated with intravenous antibiotics and mitral valve replacement. In the second case reported, a 56-year-old man with a history of hypertension, diabetes, and end-stage renal disease presented to the ED with shortness of breath, fever, and chest pain. His ECG was significant for ST-segment elevation in the lateral leads, suggestive of an AMI. This patient had a history of positive blood cultures in a previous admission as well as an echocardiogram revealing an aortic valve vegetation. Given the high suspicion for an infective endocarditis causing an embolic event that in turn led to the myocardial infarction, thrombolytics were withheld in the ED and the patient was transported for coronary catheterization. The coronary angiogram demonstrated abrupt cutoffs at the distal left anterior descending artery and distal left posterior descending artery suggestive of an embolic occlusion of these vessels. He was subsequently treated with intravenous antibiotics and aortic valve replacement. CONCLUSIONS These two cases illustrate the importance of broadening our differential in the causes of AMI. In these cases, the recognition of an embolic event from infective endocarditis as the cause of the acute coronary syndrome allowed physicians to direct their interventions to optimize the appropriate care for each patient.

Emergency department point-of-care ultrasound in out-of-hospital and in-ED cardiac arrest

BACKGROUND Point-of-care ultrasound has been suggested to improve outcomes from advanced cardiac life support (ACLS), but no large studies have explored how it should be incorporated into ACLS. Our aim was to determine whether cardiac activity on ultrasound during ACLS is associated with improved survival. METHODS We conducted a non-randomized, prospective, protocol-driven observational study at 20 hospitals across United States and Canada. Patients presenting with out-of-hospital arrest or in-ED arrest with pulseless electrical activity or asystole were included. An ultrasound was performed at the beginning and end of ACLS. The primary outcome was survival to hospital admission. Secondary outcomes included survival to hospital discharge and return of spontaneous circulation. FINDINGS 793 patients were enrolled, 208 (26.2%) survived the initial resuscitation, 114 (14.4%) survived to hospital admission, and 13 (1.6%) survived to hospital discharge. Cardiac activity on US was the variable most associated with survival at all time points. On multivariate regression modeling, cardiac activity was associated with increased survival to hospital admission (OR 3.6, 2.2-5.9) and hospital discharge (OR 5.7, 1.5-21.9). No cardiac activity on US was associated with non-survival, but 0.6% (95% CI 0.3-2.3) survived to discharge. Ultrasound identified findings that responded to non-ACLS interventions. Patients with pericardial effusion and pericardiocentesis demonstrated higher survival rates (15.4%) compared to all others (1.3%). CONCLUSION Cardiac activity on ultrasound was the variable most associated with survival following cardiac arrest. Ultrasound during cardiac arrest identifies interventions outside of the standard ACLS algorithm.

The Effect of Weight-based Volume Loading on the Inferior Vena Cava in Fasting Subjects: A Prospective Randomized Double-blinded Trial

OBJECTIVES Inferior vena cava ultrasound (IVC-US) assessment has been proposed as a noninvasive method of assessing volume status. Current literature is divided on its ability to do so. The primary objective was to compare IVC-US changes in healthy fasting subjects randomized to either 10 or 30 mL/kg of intravenous (IV) fluid administration versus a control group that received only 2 mL/kg. METHODS This was a prospective randomized double-blinded trial set in emergency department (ED) clinical care rooms. Volunteer subjects with no history of cardiac disease or hypertension fasted for 12 hours. Subjects were randomly assigned to receive IV 0.9% saline bolus of 2 (control group), 10, or 30 mL/kg over 30 minutes. IVC-US was performed before and 15 minutes after each fluid bolus. RESULTS Forty-two fasting subjects were enrolled. Analysis of variance (ANOVA) comparison showed that IVC-US was unable to detect any significant difference between the control group and those given either 10 or 30 mL/kg fluid, whether using maximum or minimum IVC diameter or caval index (IVC-CI). The groups receiving 10 and 30 mL/kg each had a statistically significant change in IVC-CI; however, the 30 mL/kg group had no significant change in either of the mean IVC diameters. CONCLUSIONS Overall, there were statistically significant differences in mean IVC-US measurements before and after fluid loading, but not between groups. Fasting asymptomatic subjects had a wide intersubject variation in both baseline IVC-US measurements and fluid-related changes. The degree of IVC-US change in association with graded acute volume loading was not predictably proportional between our subjects.

Prospective comparison of ultrasound and CXR for confirmation of central vascular catheter placement

Objective To prospectively compare ultrasound (US) versus CXR for confirmation of central vascular catheter (CVC) placement. Secondary objective was to determine the incidence of pneumothorax (PTX) and compare US with CXR completion times. Methods Investigators performed the US saline flush echo test, and evaluated each anterior hemithorax for pleural sliding with US after subclavian or internal jugular CVC placement. Measurements and main results 151 total (135 in the emergency department, 16 in the intensive care unit) patients after CVC placement, mean age 62.1±15.6 years and 83 (55%) female patients. The rapid atrial swirl sign ( RASS) was ultrasound finding of an immediate appearance of turbulence entering the right atrium via superior vena cava after a rapid saline flush of the distal CVC port. RASS was considered ‘negative’ for CVC malposition. US identified all correct CVC placements. Four suboptimal CVC tip placements were detected by CXR. US identified three of these misplacements (McNemar exact p value >0.99). There were no cases of PTX or abnormal pleural sliding by either CXR or US. Median times for US and CXR completion were 1.1 (IQR 0.7) minutes and 20 (IQR: 30) minutes, respectively, median difference 23.8 (95% CI 19.6 to 29.3) minutes, p<0.0001. Conclusions PTX and CVC tip malposition were rare after US-guided CVC placement. There was no significant difference between saline flush echo and CXR for the identification of catheter tip malposition. Benefits of US assessment for complications include reduced radiation exposure and time delays associated with CXR.

E-Point Septal Separation Compared to Fractional Shortening Measurements of Systolic Function in Emergency Department Patients Prospective Randomized Study

Rapid bedside assessment of left ventricular (LV) function can aid in the evaluation of the critically ill patient and guide clinical management. Our primary hypothesis was that mitral valve E‐point septal separation measurements would correlate with contemporaneous fractional shortening measurements of LV systolic function when performed by emergency physicians. Our secondary hypothesis was that E‐point septal separation as a continuous variable would predict fractional shortening using a linear regression model.

Team-focused Cardiopulmonary Resuscitation: Prehospital Principles Adapted for Emergency Department Cardiac Arrest Resuscitation

BACKGROUND Out-of-hospital cardiac arrest has high rates of morbidity and mortality, and a growing body of evidence is redefining our approach to the resuscitation of these high-risk patients. OBJECTIVES Team-focused cardiopulmonary resuscitation (TFCPR), most commonly deployed and described by prehospital care providers, is a focused approach to cardiac arrest care that emphasizes early defibrillation and high-quality, minimally interrupted chest compressions while de-emphasizing endotracheal intubation and intravenous drug administration. TFCPR is associated with statistically significant increases in survival to hospital admission, survival to hospital discharge, and survival with good neurologic outcome; however, the adoption of similar streamlined resuscitation approaches by emergency physicians has not been widely reported. In the absence of a deliberately streamlined approach, such as TFCPR, other advanced therapies and procedures that have not shown similar survival benefit may be prioritized at the expense of simpler evidence-based interventions. DISCUSSION This review examines the current literature on cardiac arrest resuscitation. The recent prehospital success of TFCPR is highlighted, including the associated improvements in multiple patient-centered outcomes. The adaptability of TFCPR to the emergency department (ED) setting is also discussed in detail. Finally, we discuss advanced interventions frequently performed during ED cardiac arrest resuscitation that may interfere with early defibrillation and effective high-quality chest compressions. CONCLUSION TFCPR has been associated with improved patient outcomes in the prehospital setting. The data are less compelling for other commonly used advanced resuscitation tools and procedures. Emergency physicians should consider incorporating the TFCPR approach into ED cardiac arrest resuscitation to optimize delivery of those interventions most associated with improved outcomes.

Ultrasound-guided oblique approach for peripheral venous access in a phantom model

BackgroundUltrasound (US) vascular guidance is traditionally performed in transverse (T) and longitudinal (L) axes, each with drawbacks. We hypothesized that the introduction of a novel oblique (O) approach would improve the success of US-guided peripheral venous access. We examined emergency physician (EP) performance using the O approach in a gel US phantom.MethodsIn a prospective, case control study, EPs were enrolled from four levels of physician experience including postgraduate years one to three (PGY1, PGY2, PGY3) and attending physicians. After a brief training session, each participant attempted vessel aspiration using a linear probe in T, L, and O axes on a gel US phantom. Time to aspiration and number of attempts to aspiration were recorded. The approach order was randomized, and descriptive statistics were used.ResultsTwenty-four physicians participated. The first-attempt success rate was lower for O, 45.83%, versus 70.83% for T (p = 0.03) and 83.33% for L (p = 0.01). The average time to aspiration was 12.5 s (O) compared with 9.47 s (T) and 9.74 s (L), respectively. There were no significant differences between all four groups in regard to total amount of time and number of aspiration attempts; however, a trend appeared revealing that PGY3 and attending physicians tended to aspirate in less time and by fewer attempts in all three orientations when compared with the PGY2 and PGY1 physicians.ConclusionIn this pilot study, US-guided simulated peripheral venous access using a phantom gel model in a mixed user group showed that the novel oblique approach was not initially more successful versus T and L techniques.

Interobserver and Intraobserver Agreement on Qualitative Assessments of Right Ventricular Dysfunction With Echocardiography in Patients With Pulmonary Embolism

To evaluate observer agreement using qualitative goal‐directed echocardiographic criteria for right ventricular (RV) dysfunction prognostication in submassive pulmonary embolism (PE).

Prospective evaluation of ultrasound-guided short catheter placement in internal jugular veins of difficult venous access patients

RATIONALE Difficult vascular access (DVA) is a common problem. Placement of ultrasound-guided standard length catheters (ultrasound-guided peripheral intravenous [USPIV]) in the internal jugular (IJ) vein is a potential solution. OBJECTIVES The objective of the study is to evaluate the immediate and short-term incidence of complications after USPIV placement in IJ of DVA patients. METHODS We conducted a prospective convenience study of USPIV into IJ of emergency department patients with DVA. All USPIV placements were performed with standard aseptic techniques with either an 18-gauge 6.35-cm single-lumen catheter or 20-gauge 5.7-cm catheter. Immediate complications were evaluated. Clinical follow-up consisted of review of the electronic medical record for physician and nursing documentation, laboratory data, and imaging studies in a multiple hospital network. Outcome measures 1 and 6 weeks included local site abnormalities, bleeding, local or systemic infection, pneumothorax, or thrombosis at time of placement, and death. RESULTS We enrolled 33 patients (58% female; mean age, 56.4 years; and median body mass index of 24.7). Eleven physicians performed USPIV placement. Median access time was 4.0 (interquartile range, 5.5) minutes and 1 attempt for placements. There were no immediate complications. Follow-up was successful in 5 of 7 discharged patients and 26 of 27 admitted patients. Three deaths within 6 weeks were unrelated to USPIV. Three patients lost to follow-up were not discovered on electronic medical record or death registries. No patient had catheter-related complications. CONCLUSIONS There were no immediate or short-term complications associated with aseptic USPIV placement into IJ. Ultrasound-guided peripheral intravenous IJ placement was a rapid and safe approach in DVA patients.