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This study aimed to compare running biomechanics and biomechanical variability across 3 run segments and between conditions for 5-km outdoor overground and indoor treadmill running. Seventy-one recreationally-active adults (31F, 40 M; age: 37 ± 11 years; body mass index: 22.9 ± 2.5 kg/m 2 ) completed aerobic fitness assessments at baseline (VO 2 max), outdoor overground 5 km runs on a standardized route, and indoor treadmill 5 km runs on a motorized system (12.6 ± 4.9 days apart). Wearable sensors recorded step-by-step spatiotemporal, kinetic, and kinematic biomechanics. Repeated measures analyses of covariance were used to compare mean and coefficient of variation (CV) of sensor-derived metrics across run segments, conditions, and limbs (covariates: pace, VO 2 max). Tukey's post-hoc tests with mean differences and Cohen's d effect sizes were used to determine the difference magnitudes across comparisons. Most biomechanical measures significantly differed between running conditions (p < 0.001); contact time (mean difference and standard error: 8 ± 3 ms; d = 0.20), stride length (0.20 ± 0.12 m; d: 0.31), kinetics (shock, impact, braking; 0.17-1.30 g; d-range: 0.36-0.57), and pronation velocity (138 ± 16°/s; d: 0.61) were all higher during indoor treadmill running. Indoor treadmill running biomechanics CV were significantly higher for most measures compared to outdoor overground running (p < 0.001; d-range: 0.18-0.52). Only spatiotemporal measures and CV significantly differed across run segments (d-range: 0.16-0.68). Clinicians should expect that indoor treadmill biomechanics, particularly kinetic and pronation, will be significantly higher than patients' outdoor overground running biomechanics and tailor subsequent recommendations accordingly. Furthermore, clinicians should expect that indoor treadmill running analyses may result in more variable biomechanics, potentially attributed to consistent speed and surface, and tailor assessments to preferred run environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

We report the design of a blood-contacting glucose monitor with a nitric oxide (NO)-releasing metal-organic framework (MOF) embedded within the outer polymer layer of a glucose sensor to promote the release of NO from endogenous NO donors. The sensors were tested by using amperometry across a range of glucose concentrations to assess whether the presence of either the MOF or NO decreased the performance of the glucose monitor. Even though signal response was diminished, the sensors maintained a good regression fit ( R 2 = 0.9944) and a similar dynamic range and reproducibility in the presence of S -nitrosoglutathione.

Medical devices that require substantial contact between blood and a foreign surface would be dramatically safer if constructed from materials that prevent clot formation and coagulation disturbance at the blood-biomaterial interface. Nitric oxide (NO), an endogenous inhibitor of platelet activation in the vascular endothelium, could provide anticoagulation at the blood-surface interface when applied to biomaterials. We investigated an application of a copper-based metal-organic framework, H 3 [(Cu 4 Cl) 3 (BTTri) 8 -(H 2 O) 12 ]·72H 2 O where H 3 BTTri = 1,3,5-tris(1 H -1,2,3-triazole-5-yl)benzene] (CuBTTri), which has been shown to be an effective catalyst to generate NO from S -nitrosothiols that are endogenously present in blood. A method was developed to apply a CuBTTri composite coating to Tygon medical tubing used for extracorporeal lung support devices. The stability and activity of the coating were evaluated during 72 h dynamic saline flow testing (1.5-2.5 L/min, n = 3) with scanning electron microscopy imaging and inductively coupled mass-spectroscopy analysis. Compatibility of the coating with whole blood was assessed with a panel of hemocompatibility tests during 6 h circulation of swine donor blood in an ex vivo circulation loop constructed with CuBTTri tubing or unmodified Tygon (1.5 L/min blood flow rate, n = 8/group). Thrombus deposition and catalytic activity of the CuBTTri tubing were assessed following blood exposure. The coating remained stable during 72 h saline flow experiments at clinically relevant flow rates. No adverse effects were observed relative to controls during blood compatibility testing, to include no significant changes in platelet count ( p = 0.42), platelet activation indicated by P-selectin expression ( p = 0.57), coagulation panel values, or methemoglobin fraction ( p = 0.18) over the 6 h circulation period. CuBTTri within the coating generated NO following blood exposure in the presence of biologically relevant concentrations of an NO donor. CuBTTri composite coating was stable and blood compatible in this pilot study and requires further investigation of efficacy using in vivo models conducted with clinically relevant blood flow rates and study duration.

When flowing whole blood contacts medical device surfaces, the most common blood-material interactions result in coagulation, inflammation, and infection. Many new blood-contacting biomaterials have been proposed based on strategies that address just one of these common modes of failure. This study proposes to mitigate unfavorable biological reactions that occur with blood-contacting medical devices by designing multifunctional surfaces, with features optimized to meet multiple performance criteria. These multifunctional surfaces incorporate the release of the small molecule hormone nitric oxide (NO) with surface chemistry and nanotopography that mimic features of the vascular endothelial glycocalyx. These multifunctional surfaces have features that interact with coagulation components, inflammatory cells, and bacterial cells. While a single surface feature alone may not be sufficient to achieve multiple functions, the release of NO from the surfaces along with their modification to mimic the endothelial glycocalyx synergistically improves platelet-, leukocyte-, and bacteria-surface interactions. This work demonstrates that new blood-compatible materials should be designed with multiple features, to better address the multiple modes of failure of blood-contacting medical devices., (© 2021 Wiley-VCH GmbH.)

Introduction: Emergency department (ED) patients are frequently ventilated with excessively large tidal volumes for predicted body weight based on height, which has been linked to poorer patient outcomes. We hypothesized that supplying tape measures to respiratory therapists (RT) would improve measurement of actual patient height and adherence to a lung-protective ventilation strategy in an ED-intensive care unit (ICU) environment., Methods: On January 14, 2019, as part of a ventilator-associated pneumonia prevention bundle in our ED-based ICU, we began providing RTs with tape measures and created a best practice advisory reminding them to record patient height. We then retrospectively collected data on patient height and tidal volumes before and after the intervention., Results: We evaluated 51,404 tidal volume measurements in 1,826 patients over the 4 year study period; of these patients, 1,579 (86.5%) were pre-intervention and 247 (13.5%) were post-intervention. The intervention was associated with a odds of the patient's height being measured were 10 times higher post-intervention (25.1% vs 3.2%, P <0.05). After the bundle was initiated, we observed a significantly higher percentage of patients ventilated with mean tidal volumes less than 8 cubic centimeters per kilogram (93.9% vs 84.5% P < 0.05)., Conclusion: Patients in an ED-ICU environment were ventilated with a lung-protective strategy more frequently after an intervention reminding RTs to measure actual patient height and providing a tape measure to do so. A significantly higher percentage of patients had height measured rather than estimated after the intervention, allowing for more accurate determination of ideal body weight and calculation of lung-protective ventilation volumes. Measuring all mechanically ventilated patients' height with a tape measure is an example of a simple, low-cost, scalable intervention in line with guidelines developed to improve the quality of care delivered to critically ill ED patients.

Background: Patient motion can lead to misalignment of left ventricular (LV) volumes-of-interest (VOIs) and subsequently inaccurate quantification of myocardial blood flow (MBF) and flow reserve (MFR) from dynamic PET myocardial perfusion images. We aimed to develop an image-based 3D-automated motion-correction algorithm that corrects the full dynamic sequence for translational motion, especially in the early blood phase frames (~ first minute) where the injected tracer activity is transitioning from the blood pool to the myocardium and where conventional image registration algorithms have had limited success., Methods: We studied 225 consecutive patients who underwent dynamic rest/stress rubidium-82 chloride ( 82 Rb) PET imaging. Dynamic image series consisting of 30 frames were reconstructed with frame durations ranging from 5 to 80 seconds. An automated algorithm localized the RV and LV blood pools in space and time and then registered each frame to a tissue reference image volume using normalized gradient fields with a modification of a signed distance function. The computed shifts and their global and regional flow estimates were compared to those of reference shifts that were assessed by three physician readers., Results: The automated motion-correction shifts were within 5 mm of the manual motion-correction shifts across the entire sequence. The automated and manual motion-correction global MBF values had excellent linear agreement (R = 0.99, y = 0.97x + 0.06). Uncorrected flows outside of the limits of agreement with the manual motion-corrected flows were brought into agreement in 90% of the cases for global MBF and in 87% of the cases for global MFR. The limits of agreement for stress MBF were also reduced twofold globally and by fourfold in the RCA territory., Conclusions: An image-based, automated motion-correction algorithm for dynamic PET across the entire dynamic sequence using normalized gradient fields matched the results of manual motion correction in reducing bias and variance in MBF and MFR, particularly in the RCA territory.

Introduction: Extubation of appropriate patients in the emergency department (ED) may be a strategy to avoid preventable or short-stay intensive care unit (ICU) admissions, and could allow for increased ventilator and ICU bed availability when demand outweighs supply. Extubation is infrequently performed in the ED, and a paucity of outcome data exists. Our objective was to descriptively analyze characteristics and outcomes of patients extubated in an ED-ICU setting., Methods: We conducted a retrospective observational study at an academic medical center in the United States. Adult ED patients extubated in the ED-ICU from 2015-2019 were retrospectively included and analyzed., Results: We identified 202 patients extubated in the ED-ICU; 42% were female and median age was 60.86 years. Locations of endotracheal intubation included the ED (68.3%), outside hospital ED (23.8%), and emergency medical services/prehospital (7.9%). Intubations were performed for airway protection (30.2%), esophagogastroduodenoscopy (27.7%), intoxication/ingestion (17.3%), respiratory failure (13.9%), seizure (7.4%), and other (3.5%). The median interval from ED arrival to extubation was 9.0 hours (interquartile range 6.2-13.6). One patient (0.5%) required unplanned re-intubation within 24 hours of extubation. The attending emergency physician (EP) at the time of extubation was not critical care fellowship trained in the majority (55.9%) of cases. Sixty patients (29.7%) were extubated compassionately; 80% of these died in the ED-ICU, 18.3% were admitted to medical-surgical units, and 1.7% were admitted to intensive care. Of the remaining patients extubated in the ED-ICU (n = 142, 70.3%), zero died in the ED-ICU, 61.3% were admitted to medical-surgical units, 9.9% were admitted to intensive care, and 28.2% were discharged home from the ED-ICU., Conclusion: Select ED patients were safely extubated in an ED-ICU by EPs. Only 7.4% required ICU admission, whereas if ED extubation had not been pursued most or all patients would have required ICU admission. Extubation by EPs of appropriately screened patients may help decrease ICU utilization, including when demand for ventilators or ICU beds is greater than supply. Future research is needed to prospectively study patients appropriate for ED extubation.

Background: Patient motion can lead to misalignment of left ventricular volumes of interest and subsequently inaccurate quantification of myocardial blood flow (MBF) and flow reserve (MFR) from dynamic PET myocardial perfusion images. We aimed to identify the prevalence of patient motion in both blood and tissue phases and analyze the effects of this motion on MBF and MFR estimates., Methods: We selected 225 consecutive patients that underwent dynamic stress/rest rubidium-82 chloride ( 82 Rb) PET imaging. Dynamic image series were iteratively reconstructed with 5- to 10-second frame durations over the first 2 minutes for the blood phase and 10 to 80 seconds for the tissue phase. Motion shifts were assessed by 3 physician readers from the dynamic series and analyzed for frequency, magnitude, time, and direction of motion. The effects of this motion isolated in time, direction, and magnitude on global and regional MBF and MFR estimates were evaluated. Flow estimates derived from the motion corrected images were used as the error references., Results: Mild to moderate motion (5-15 mm) was most prominent in the blood phase in 63% and 44% of the stress and rest studies, respectively. This motion was observed with frequencies of 75% in the septal and inferior directions for stress and 44% in the septal direction for rest. Images with blood phase isolated motion had mean global MBF and MFR errors of 2%-5%. Isolating blood phase motion in the inferior direction resulted in mean MBF and MFR errors of 29%-44% in the RCA territory. Flow errors due to tissue phase isolated motion were within 1%., Conclusions: Patient motion was most prevalent in the blood phase and MBF and MFR errors increased most substantially with motion in the inferior direction. Motion correction focused on these motions is needed to reduce MBF and MFR errors.

S-Nitrosothiols (RSNOs) such as S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylpenicillamine (SNAP) are susceptible to decomposition by stimuli including heat, light, and trace metal ions. Using stepwise isothermal thermogravimetric analysis (TGA), we observed that NO-forming homolytic cleavage of the S-N bond occurs at 134.7 ± 0.8 °C in GSNO and 132.8 ± 0.9 °C in SNAP, contrasting with the value of 150 °C that has been previously reported for both RSNOs. Using mass spectrometry (MS), nuclear magnetic resonance (NMR), and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), we analyzed the decomposition products from TGA experiments. The organic product of GSNO decomposition was glutathione disulfide, while SNAP decomposed to form N-acetylpenicillamine disulfide as well as other products, including tri- and tetrasulfides. In addition, we assessed the relative solution stabilities of GSNO and SNAP under common laboratory conditions, which include variable temperature, pH, and light exposure with rigorous exclusion of trace metal ions by chelation. GSNO exhibited greater stability than SNAP over a 7-day period except in one instance. Both RSNOs demonstrated an inverse relationship between solution stability and temperature, with refrigeration considerably extending shelf life. A decrease in pH from 7.4 to 5.0 also enhanced the stability of both RSNOs. A further decrease in pH from 5.0 to 3.0 resulted in decreased stability for both RSNOs, and is notably the only occasion in which SNAP proved more stable than GSNO. After 1 h of exposure to overhead fluorescent lighting, both RSNOs displayed high susceptibility to light-induced decomposition. After 7 h, GSNO and SNAP decomposed 19.3 ± 0.5% and 30 ± 2%, respectively., (Copyright © 2019 Elsevier Inc. All rights reserved.)

S-Nitrosothiols (RSNOs) such as S-nitrosoglutathione (GSNO) are known to produce nitric oxide (NO) through thermal, photolytic, and metal ion-promoted pathways, which has led to their increasing use as exogenous sources of therapeutic NO. Despite the burgeoning NO release applications for RSNOs, their susceptibility to metal-promoted decomposition has rarely been examined in a uniform manner through the specific measurement of NO release. In this study, the ability of various transition and post-transition metal ions to promote NO release from GSNO was surveyed by chemiluminescence-based NO detection. Substantial NO formation (>10-fold increase relative to GSNO baseline) was detected after the addition of Cu 2+ , Au 3+ , Pd 2+ , Pt 2+ , and V 3+ . Modest increases were observed in the cases of Co 2+ , Hf 4+ , Fe 2+ , Fe 3+ , Mn 2+ , Hg 2+ , Ni 2+ , Ag + , Sn 2+ , and Zr 4+ , while no effect was evident for Al 3+ , Cr 3+ , Pb 2+ , Sc 3+ , and Zn 2+ . It was further observed that In + compounds initiate the apparent NO-forming decomposition of GSNO, while In 0 and In 3+ are inactive, indicating that In + exerts a previously unknown effect on GSNO., (Copyright © 2019. Published by Elsevier Inc.)