Intranasal Dexmedetomidine Use in Pediatric Patients for Anxiolysis in the Emergency Department.

OBJECTIVES: In recent years, dexmedetomidine has gained traction as a treatment for anxiolysis in the emergency department (ED). When used with an atomizer, it may also be given intranasally for anxiolysis. The primary objective was to determine the level of ED provider satisfaction and comfort with intranasal (IN) dexmedetomidine for anxiolysis in pediatric patients with behavioral agitation and/or acute psychosis. The secondary objectives included determining safety, rates of therapy failure, and ED length of stay compared with oral midazolam. The efficacy of IN dexmedetomidine versus oral midazolam in patients with autism spectrum disorder (ASD) was also evaluated. METHODS: This was a single-center, prospective study in a pediatric ED from March 1 to December 31, 2021. Patients were included in the study if the ED provider requested IN dexmedetomidine anxiolysis and completed a postadministration survey. Safety and efficacy outcomes were assessed by chart review and compared with patients who received oral midazolam during the same study period. Efficacy was defined as the rate of treatment failure, as the need for procedural termination, progression to procedural sedation, or the requirement of additional medications for anxiolysis. RESULTS: Sixty-two patients received IN dexmedetomidine {median dose [interquartile range (IQR)] of 3.05 [2.04-4.00] µg/kg/dose} compared with 58 who received oral midazolam [median (IQR) dose of 0.29 (0.25-0.48) mg/kg/dose). Providers reported high comfort and satisfaction scores, with median (IQR) scores of 90 (75-100) and 88 (60-100) of 100. Twenty-nine percent of patients experienced treatment failure, most commonly because of the need for additional medications. Those who received IN dexmedetomidine had a longer ED length of stay (6.0 vs 4.4 hours, P = 0.010). Among the patients with ASD, those who received IN dexmedetomidine had a lower rate of treatment failure compared with oral midazolam (21.2% vs 66.7%, P = 0.039). CONCLUSIONS: This study demonstrates that IN dexmedetomidine has high levels of provider comfort and satisfaction, moderately high success rate, and a promising safety profile. In addition, IN dexmedetomidine may be superior to oral midazolam in patients with ASD for anxiolysis, but additional studies are needed.

Use and Cost Analysis of Comprehensive Respiratory Panel Testing in a Pediatric Emergency Department.

OBJECTIVES: Fever and respiratory infections are among the leading causes of pediatric emergency department visits and hospitalizations. Although typically self-resolving, clinicians may perform diagnostic tests to determine microbial etiologies of these illnesses. Although comprehensive respiratory viral panels can quickly identify causative organisms, cost to the hospital and patient may be significant. The objective of this study was to analyze the financial impact of comprehensive respiratory viral panel use in relation to associated clinical outcomes. METHODS: This study was a single-center, retrospective chart review of pediatric emergency department patients who were evaluated between October 1, 2016, and April 30, 2018, with International Classification of Diseases, Tenth Revision (ICD-10) code diagnoses of acute upper respiratory infection, fever unspecified, and/or bronchiolitis. Our primary outcome was the effect of comprehensive respiratory viral panel testing and results on the total health care charge to patients. Secondary outcomes were the effect of comprehensive respiratory viral panel testing and results on emergency department length of stay and antimicrobial use. RESULTS: A total of 5766 visits were included for primary analysis, with 229 (4%) undergoing comprehensive respiratory viral panel testing. Of these, 163 had a positive result (71%) for at least 1 organism. The total cost was significantly higher in the group that underwent comprehensive respiratory viral panel testing ($643.39 [$534.18-$741.15] vs $295.15 [$249.72-$353.92]; P < 0.001). There was no decrease in emergency department length of stay or significant change in antimicrobial use associated with comprehensive respiratory viral panel use. CONCLUSIONS: This study demonstrates that the utilization of comprehensive respiratory viral panels in pediatric emergency department patients with bronchiolitis, unspecified fever, and/or acute upper respiratory infection adds significant cost to patient care without a decrease in their length of stay or antimicrobial use. Further studies are needed to determine the appropriate targeted use of comprehensive respiratory viral panels.

Comprehensive analyses of ventricular myocyte models identify targets exhibiting favorable rate dependence.

Reverse rate dependence is a problematic property of antiarrhythmic drugs that prolong the cardiac action potential (AP). The prolongation caused by reverse rate dependent agents is greater at slow heart rates, resulting in both reduced arrhythmia suppression at fast rates and increased arrhythmia risk at slow rates. The opposite property, forward rate dependence, would theoretically overcome these parallel problems, yet forward rate dependent (FRD) antiarrhythmics remain elusive. Moreover, there is evidence that reverse rate dependence is an intrinsic property of perturbations to the AP. We have addressed the possibility of forward rate dependence by performing a comprehensive analysis of 13 ventricular myocyte models. By simulating populations of myocytes with varying properties and analyzing population results statistically, we simultaneously predicted the rate-dependent effects of changes in multiple model parameters. An average of 40 parameters were tested in each model, and effects on AP duration were assessed at slow (0.2 Hz) and fast (2 Hz) rates. The analysis identified a variety of FRD ionic current perturbations and generated specific predictions regarding their mechanisms. For instance, an increase in L-type calcium current is FRD when this is accompanied by indirect, rate-dependent changes in slow delayed rectifier potassium current. A comparison of predictions across models identified inward rectifier potassium current and the sodium-potassium pump as the two targets most likely to produce FRD AP prolongation. Finally, a statistical analysis of results from the 13 models demonstrated that models displaying minimal rate-dependent changes in AP shape have little capacity for FRD perturbations, whereas models with large shape changes have considerable FRD potential. This can explain differences between species and between ventricular cell types. Overall, this study provides new insights, both specific and general, into the determinants of AP duration rate dependence, and illustrates a strategy for the design of potentially beneficial antiarrhythmic drugs.

Hemodynamics of ulcerated plaques: before and after.

The hemodynamics and fluid mechanical forces in blood vessels have long been implicated in the deposition and growth of atherosclerotic plaque. Detailed information about the hemodynamics in vessels affected by significant plaque deposits can also provide insight into the mechanisms and likelihood of plaque weakening and rupture. In the current study, the governing equations are solved in their finite volume formulation in several patient-specific stenotic geometries. Of specific interest are the flow patterns and forces near ulcerations in the plaque. The flow patterns and forces in vessels with ulcerated plaques are compared with those in stenotic vessels without evidence of ulceration and to the hemodynamics in the same vessels as they likely appeared prior to ulceration. Hemodynamics "before" and "after" hemorrhage may suggest fluid mechanical and morphological factors of diagnostic and predictive value. Recirculation zones, vortex shedding, and secondary flows are captured by both laminar and turbulent solutions. The forces on vessel walls are shown to correlate with unstable plaque deposits. Performing before and after studies of vessels in long-term radiology studies may illuminate mechanisms of hemorrhage and other vessel remodeling.