Standardized Temporary Atrial Epicardial Wire Locations Lead to Enhanced Atrial Signal Identification.

Background: Arrhythmias, common after pediatric cardiac surgery, are associated with increased morbidity and mortality. Atrial epicardial wires (AEW) improve diagnostic accuracy but have variable pacing and sensing properties based on their location. Even so, there are no longitudinal prospective pediatric studies examining ideal placement of AEW. Methods: This multicenter study compared atrial amplitudes, pacing sensitivities and thresholds via AEW placed at Bachmann's Bundle (BB) and the interatrial groove near the right pulmonary veins (IGRPV) versus the surgeons' standard locations. An AtriAmp system was used to obtain an atrial ECG to calculate atrial and ventricular amplitude from atrial electrograms on the bedside monitor. Sensitivities and thresholds via a temporary pacemaker were documented. ANOVA tests with repeated measures and post-hoc pairwise comparisons were performed to compare variables within the first 24-h postoperative hours. Mixed effects linear regression models were employed to examine daily trends. Results: In the first 24-h following cardiac surgery, AEW at BB and IGRPV showed significantly larger atrial amplitudes than the surgeons' standard locations. In addition, there was a negative trend in atrial ECG amplitude in all AEW from postoperative days 0 to 1; however, subsequent days showed a positive mean change in atrial amplitude with largest increase seen at BB. Atrial sensing as measured by the temporary pacemaker had statistically greater atrial signal amplitude from the BB-IGRPV set in both polarities (ie, with the BB as the - or + electrode pair) as compared to the surgeons' standard locations. No difference in atrial thresholds (mA) were noted in the immediate postoperative period or over time, with a relatively low atrial threshold at all sites. Conclusion: Standardization of AEW at Bachmann's Bundle can yield largest atrial amplitudes by atrial ECG and highest atrial sensing parameters without compromising atrial thresholds.

Management of esophageal button battery ingestions: resource utilization and outcomes.

PURPOSE: Institutions are adopting the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) guidelines for pediatric esophageal button battery ingestion (EBBI). Our objective was to evaluate the guidelines' impact on in-hospital resource utilization and short-term clinical outcomes in hemodynamically stable patients after endoscopic battery removal. METHODS: A single-center retrospective review of all EBBI admissions from 2010 to 2020. Patients were divided into two groups based on adoption of national guidelines: pre-guideline (2010-2015) and post-guideline (2016-2020). RESULTS: Sixty-five patients were studied (pre-guideline n = 23; post-guideline n = 42). Compared with pre-guideline, post-guideline use of magnetic resonance imaging (MRI) increased (2/23 [8.7%]; 30/42 [71.4%]; p < 0.001). Post-guideline increases resulted for median days (IQR) receiving antibiotics (0 [0, 4]; 6 [3, 8]; p = 0.01), total pediatric intensive care unit admission (0 [0, 1]; 3 [0, 6]; p < 0.001), and total hospital length of stay (5 [2, 11]; 11.5 [4, 17]; p = 0.02). Two patients in the post-guideline group had delayed presentations despite normal imaging: one with TEF and one with aorto-esophageal fistula. All survived to discharge. CONCLUSION: In EBBI cases managed using the consensus based NASPHAGN guidelines, we report increased resource utilization without improved patient outcomes. Further research should evaluate post-guideline costs and resource utilization.

Cerebrovascular reactivity measured in awake mice using diffuse correlation spectroscopy.

Significance: Cerebrovascular reactivity (CVR), defined as the ability of the cerebral vasculature to dilate or constrict in response to a vasoactive stimulus, is an important indicator of the brain's vascular health. However, mechanisms of cerebrovascular dysregulation are poorly understood, and no effective treatment strategies for impaired CVR exist. Preclinical murine models provide an excellent platform for interrogating mechanisms underlying CVR dysregulation and determining novel therapeutics that restore impaired CVR. However, quantification of CVR in mice is challenging. Aim: We present means of assessing CVR in awake mice using intraperitoneal injection of acetazolamide (ACZ) combined with continuous monitoring of cerebral blood flow. Approach: Measurements of cerebral blood flow were made with a minimally invasive diffuse correlation spectroscopy sensor that was secured to an optical window glued to the intact skull. Two source-detector separations (3 and 4.5 mm) per hemisphere were used to probe different depths. CVR was quantified as the relative increase in blood flow due to ACZ. CVR was assessed once daily for 5 days in 5 mice. Results: We found that CVR and the response half-time were remarkably similar across hemispheres and across 3- versus 4.5-mm separations, suggesting a homogenous, whole brain response to ACZ. Mean(std) intra- and intermouse coefficients of variations were 15(9)% and 19(10)%, respectively, for global CVR and 24(15)% and 27(11)%, respectively, for global response half-time. Conclusion: In sum, we report a repeatable method of measuring CVR in free-behaving mice which can be used to screen for impairments with disease and to track changes in CVR with therapeutic interventions.