Twenty-four hour ambulatory electrocardiographic recording using a Medilog tape recorder was attempted in 16 healthy pet dogs weighing between 18.4 and 34 kg, while they were living in familiar surroundings. Full 24-hour records were obtained from 10 of them and recordings of more than 10 hours duration from two others; and the findings in these recordings were similar. Maximum heart rates ranged between 110 and 300 beats/minute and the minimum rates ranged between 17 and 46 beats/minute. Intermittent ventricular premature complexes were recorded from these apparently healthy dogs and all but one dog demonstrated a sinus pause, longer than two seconds; the longest pause was 5.7 seconds. The pauses were associated with marked sinus arrhythmia and occurred in both brachycephalic and non-brachycephalic breeds.

Objectives To evaluate the impact of transcervical ultrasound (US) as the initial imaging study for suspected peritonsillar abscesses (PTAs) on pediatric emergency department (ED) throughput measures. Methods A retrospective cohort study of patients evaluated for suspected PTAs between January 2009 and April 2017 was conducted. We compared the ED length of stay (LOS) before and after implementation of transcervical US to diagnose a PTA. The balancing measure was the rate of return visits within 2 weeks. Results There were 387 eligible patients over the study period. A total of 101 patients were evaluated for PTAs with computed tomography and 286 with US. The mean LOS was significantly less for patients who had US (347 minutes; 95% confidence interval [CI], 330, 364 minutes) compared to computed tomography (426 minutes; 95% CI, 392, 459 minutes), with an absolute difference of 79 minutes (95% CI, 44, 113 minutes). Patients who were evaluated with US did not have an increased rate of return visits (5.9% versus 8.0%; P = .66). Conclusions The introduction of transcervical US was associated with a decrease of greater than 1 hour in the ED LOS for patients with suspected PTAs. Given the better radiation profile of US and no increase in the rate of return visits after its implementation, we propose the adoption of a transcervical US‐first approach for the diagnosis of PTAs in pediatrics.

Background Coarctation of the aorta (CoA) is associated with decreased exercise capacity despite successful repair. Altered flow patterns have been identified due to abnormal aortic arch geometry. Our previous work demonstrated aorta size mismatch to be associated with exercise intolerance in this population. In this study, we studied aortic flow patterns during simulations of exercise in repaired CoA using 4D flow cardiovascular magnetic resonance (CMR) using aortic replicas connected to an in vitro flow pump and correlated findings with exercise stress test results to identify biomarkers of exercise intolerance. Methods Patients with CoA repair were retrospectively analyzed after CMR and exercise stress test. Each aorta was manually segmented and 3D printed. Pressure gradient measurements from ascending aorta (AAo) to descending aorta (DAo) and 4D flow CMR were performed during simulations of rest and exercise using a mock circulatory flow loop. Changes in wall shear stress (WSS) and secondary flow formation (vorticity and helicity) from rest to exercise were quantified, as well as estimated DAo Reynolds number. Parameters were correlated with percent predicted peak oxygen consumption (VO2max) and aorta size mismatch (DAAo/DDAo). Results Fifteen patients were identified (VO2max 47 to 126% predicted). Pressure gradient did not correlate with VO2max at rest or exercise. VO2max correlated positively with the change in peak vorticity (R = 0.55, p = 0.03), peak helicity (R = 0.54, p = 0.04), peak WSS in the AAo (R = 0.68, p = 0.005) and negatively with peak WSS in the DAo (R = − 0.57, p = 0.03) from rest to exercise. DAAo/DDAo correlated strongly with change in vorticity (R = − 0.38, p = 0.01), helicity (R = − 0.66, p = 0.007), and WSS in the AAo (R = − 0.73, p = 0.002) and DAo (R = 0.58, p = 0.02). Estimated DAo Reynolds number negatively correlated with VO2max for exercise (R = − 0.59, p = 0.02), but not rest (R = − 0.28, p = 0.31). Visualization of streamline patterns demonstrated more secondary flow formation in aortic arches with better exercise capacity, larger DAo, and lower Reynolds number. Conclusions There are important associations between secondary flow characteristics and exercise capacity in repaired CoA that are not captured by traditional pressure gradient, likely due to increased turbulence and inefficient flow. These 4D flow CMR parameters are a target of investigation to identify optimal aortic arch geometry and improve long term clinical outcomes after CoA repair.

BackgroundPrior studies showed that point-of-care ultrasound (POCUS) training is not commonly offered in pediatric residency. We assessed the need for a pediatric POCUS curriculum by evaluating pediatric trainees' attitudes toward the use of POCUS and identifying barriers to training. We also aimed to evaluate the impact of a POCUS educational intervention on self-efficacy and behavior. MethodsWe conducted a cross-sectional survey of pediatric residents in a single large freestanding children's hospital distributed via an institutional listserv and administered online. The survey included opinionrating of statements regarding POCUS and barriers to training. We also offered a two-week POCUS course with online modules and hands-on scanning. Participating residents completed pre-and post-course knowledge assessments and follow-up surveys up to 12 months following the course to assess POCUS use and self-report confidence on POCUS indications, acquisition, interpretation, and clinical application. ResultsForty-nine respondents were included in the survey representing all three pediatric levels with 16 specialty interest areas. Ninety-six percent of trainees reported that POCUS is an important skill in pediatrics. Ninety-two percent of trainees reported that residency programs should teach residents how to use POCUS. The most important perceived barriers to POCUS training were scheduling availability for POCUS rotations and lack of access to an ultrasound machine. Fourteen participants completed the pre-and post-course knowledge tests, with eight and six participants also completing the six-and 12-month follow-up surveys, respectively. Self-ratings of confidence were significantly improved post-intervention in indications (P = 0.007), image acquisition (P = 0.002), interpretation (P = 0.002), and clinical application (P = 0.004). This confidence improvement was sustained up to 6-12 months (P = 0.004-0.032). Participants also reported higher categorical POCUS use after course completion (P = 0.031). ConclusionsPediatric trainees perceive POCUS as an important skill, hold favorable opinions towards the use of POCUS, and support POCUS training within a pediatric residency. A POCUS course can improve resident POCUS knowledge, instill confidence, and motivate higher POCUS use. Further study is needed to evaluate POCUS applications in pediatric medicine to develop a standardized POCUS curriculum and establish a training guideline for pediatric residency.

Title: Lead dust fall deposition rates during deconstruction of wood frame buildings in an urban region in the Northeastern United States. Objectives: Determine the lead dust fall deposition rate due to hybrid deconstruction (separation and removal of building components) of wood-frame structures, and compare that to the lead dust fall deposition rate from demolition (compression and collapse of building components). Scope: A city block with a total of 11 wood-frame structures was selected as the location for the deconstruction leadfall testing. Testing was done during the deconstruction of 7 of the 11 pre-1950 homes (mean construction year 1928, mean floor area 283 square meter). Method: During deconstruction, the lead deposition rate was measured by using the modified APHA 502 method (Mucha et al. 2009). Findings: The geometric mean deposition rate for the lead dust fall at the property perimeter from the houses using deconstruction was 61.3 ug/sg m/hr. Published values for deposition rates from demolition in Chicago (Jacobs, et al. 2013) are 59.0 and 152 ug/sq m/hr for homes with and without the use of dust suppression. The deposition rate during hybrid deconstruction is similar to the deposition rate during demolition when dust suppression is employed. Implications: Many older urban areas have abandoned buildings containing lead-based paint. Governments in these regions invest in removing these buildings, using a variety of methods. To avoid further lead contamination in the soil surrounding these buildings, methods which minimize the total lead dust fall must be employed. The proper quantification and evaluation of these methods will help policy makers with their decisions.