Diagnostic accuracy and temporal impact of ultrasound in patients with dyspnea admitted to the emergency department.

OBJECTIVE: Few studies have prospectively evaluated the diagnostic accuracy and temporal impact of ultrasound in the emergency department (ED) in a randomized manner. In this study, we aimed to perform a randomized, standard therapy controlled evaluation of the diagnostic accuracy and temporal impact of a standardized ultrasound strategy, versus standard care, in patients presenting to the ED with acute dyspnea. METHODS: The patients underwent a standardized ultrasound examination that was blinded to the team caring for the patient. Ultrasound results remained blinded in patients randomized to the treating team but were unblinded in the interventional cohort. Scans were performed by trained emergency physicians. The gold standard diagnosis (GSDx) was determined by two physicians blinded to the ultrasound results. The same two physicians reviewed all data >30 days after the index visit. RESULTS: Fifty-nine randomized patients were enrolled. The mean±standard deviation age was 54.4±11 years, and 37 (62%) were male. The most common GSDx was acute heart failure with reduced ejection fraction in 13 (28.3%) patients and airway diseases such as acute exacerbation of asthma or chronic obstructive pulmonary disease in 10 (21.7%). ED diagnostic accuracy, as compared to the GSDx, was 76% in the ultrasound cohort and 79% in the standard care cohort (P=0.796). Compared with the standard care cohort, the final diagnosis was obtained much faster in the ultrasound cohort (mean±standard deviation: 12±3.2 minutes vs. 270 minutes, P<0.001). CONCLUSION: A standardized ultrasound approach is equally accurate, but enables faster ED diagnosis of acute dyspnea than standard care.

Bedside Echocardiography and Passive Leg Raise as a Measure of Volume Responsiveness in the Emergency Department.

OBJECTIVES: The aim of this study was to investigate the value of bedside echocardiography with a passive leg raise as a noninvasive marker of volume responsiveness. METHODS: This work was a prospective observational study of patients with end-stage renal disease presenting to the emergency department. The left ventricular outflow tract (LVOT) velocity time integral (VTI) was obtained. Measurements before and after dialysis as well as before and after the passive leg raise were recorded. RESULTS: Fifty-four patients were enrolled, in whom the mean volume of fluid removed ± SD was 3.89 ± 0.91 L. In the predialysis cohort, the mean LVOT VTI was 28.05 cm (95% confidence interval [CI], 26.55-29.55 cm). After the passive leg raise, the mean VTI was 28.52 cm (95% CI, 26.98-30.07 cm). In the postdialysis cohort, the mean VTI was 30.31 cm (95% CI, 28.92-31.69 cm), and it increased to 34.91 cm (95% CI, 33.11-36.72 cm) after the passive leg raise. The Δ VTI values were 1.83% (95% CI, 0.12%-3.55%) in the predialysis group and 15.05% (95% CI, 12.76%-17.34%) in the postdialysis cohort. When stratified by fluid removal, the mean Δ VTI values after hemodialysis were 12.64% (95% CI, 9.79%-15.49%) and 16.84% (95% CI, 13.47%-20.22%) for patients who had less than 4 L and 4 L or greater removed, respectively. In patients without congestive heart failure, the Δ VTI was 15.28% (95% CI, 12.25%-18.32%), whereas for those with congestive heart failure, the mean change was 14.63% (95% CI, 10.91%-18.35%). CONCLUSIONS: The LVOT VTI in conjunction with a passive leg raise seems to correlate with the volume status and volume responsiveness.

Corrected carotid flow time and passive leg raise as a measure of volume status.

BACKGROUND: The aim of this study was to investigate the value of corrected carotid flow time (FTc) with passive leg raise (PLR) as a non-invasive marker of volume status in end stage renal disease (ESRD) patients. METHODS: Prospective observational study of ESRD patients presenting to the Emergency department requiring hemodialysis. The common carotid artery was evaluated in long axis. Flow time measurements pre- and post-dialysis as well as before and after PLR were recorded. RESULTS: 54 patients were enrolled, of which, 30 (55%) were male. The mean age was 47.4 years. The mean volume of fluid removed was 3.89 ±â€¯0.91 L. In the pre-dialysis cohort, the mean FTc was 340.16 ms (95% CI, 330.36-349.95). Following PLR, the mean FTc was 341.34 ms (95% CI 331.74-350.94). In the post hemodialysis cohort, the mean FTc was 302.48 ms (95% CI, 293.63-311.32). Following the PLR maneuver, the mean FTc was 340.49 ms (95% CI 331.97-349.02). The mean decrease in corrected carotid flow time was 19.15 ms (95% CI, 22.86-41.17), 32.02 ms (95% CI 4.05-34.25) and 41.17 ms (95% CI, 36.47-54.76) for patients who had <3 L, 3-4 L and >4 L removed, respectively. In patients without CHF, the mean decrease in FTc after hemodialysis was 38.80 ms (95% CI, 30.12-47.49) whereas for CHF patients the mean decrease was 35.60 ms (95% CI, 25.05-46.15). CONCLUSION: Corrected flow time in conjunction with passive leg raise seem to correlate with volume status in hemodialysis patients.

Mitral valve velocity time integral and passive leg raise as a measure of volume responsiveness.

BACKGROUND: Fluid responsiveness is an important topic for clinicians. Aggressive hydration has been shown to lead to worse outcomes. The aim of this study was to investigate the sensitivity and specificity of mitral valve (MV) velocity time integral (VTI) as a non-invasive marker of volume responsiveness. METHODS: This was a prospective observational study conducted in a tertiary emergency department. End-stage renal disease patients presenting to the emergency department requiring emergent hemodialysis were enrolled. A focused echocardiogram was done on enrolled patients. Two sets of measurements were obtained before and after hemodialysis. During each scanning session, the left ventricular outflow tract and the mitral valve VTI were obtained before and after a passive leg raise maneuver. RESULTS: 54 patients were enrolled, of which, 30 (55%) were male. The mean age was 47.4 years. The mean volume of fluid removed was 3.89 ± 0.91 L. All patients had a diagnosis of hypertension, 22 (41%) patients were diabetic, 14 (26%) patients had coronary artery disease, and 19 (35%) patients had congestive heart failure. The mean change in LVOT VTI was 1.83% (95% CI 0.12-3.55) in the pre-dialysis group and 15.05% (95% CI 12.76-17.34) in the post-hemodialysis cohort. The mean change in MV VTI was 3.74% (95% CI 2.84-4.65) in the pre-dialysis cohort and 12.95% (95% CI 11.50-14.39) in the post-dialysis cohort. For patients who had < 4 L removed, the mean delta LVOT VTI post-hemodialysis was 12.64% (95% CI 9.79-15.49) and the mean delta MV VTI was 10.48% (95% CI 8.28-12.69). For patients who had > 4 L removed, the mean delta LVOT VTI was 16.84% (95% CI 13.47-20.22) and the mean MV VTI was 14.77% (95% CI 13.03-16.51). Mitral valve VTI with PLR was found to have a sensitivity of 89.18% and a specificity of 94.11% in detecting volume responsiveness. CONCLUSION: Mitral valve velocity time integral in conjunction with passive leg raise seem to correlate with volume responsiveness in hemodialysis patients.