Milwaukee VA Medical Center

Introduction: We investigated the impact of COVID-19 on physical activity (PA) in a veteran population with implanted cardiac devices by analyzing data from the devices’ embedded accelerometers. These accelerometers provide continuous, objective measurements of PA without requiring active patient participation or incurring additional costs, making them valuable for longitudinal monitoring and clinical research. Compared to pedometers, accelerometers have demonstrated superior accuracy and reliability in assessing physical activity levels. Methods: A total of 734 veterans with implanted Medtronic pacemakers or defibrillators at the Milwaukee VA Medical Center were screened for inclusion following IRB approval. Of these, 360 patients (aged 36–100 years; mean age 75.5 years) had continuous device-derived physical activity (PA) data available from 2018 through 2022. Data from 2018 and 2019 were categorized as the pre-COVID control period, while data from 2020, 2021, and 2022 were analyzed as the post-COVID study period. Results: There was a significant decline in physical activity (PA) recorded by the implanted cardiac devices between the pre-COVID and post-COVID periods (3.00 hr/day vs. 2.64 hr/day), representing a mean decrease of 0.37 hr/day (95% CI: 0.29 to 0.45; p < 0.0001). This downward trend in PA persisted even after public health restrictions were lifted. Conclusions: In a veteran population with implanted cardiac devices, physical activity significantly declined following the onset of COVID-19 and remained reduced through 2022, despite the lifting of public health restrictions. These findings highlight the lasting impact of the pandemic on functional status and underscore the value of device-based monitoring for long-term health surveillance. This has important implications for managing physical activity and health outcomes during future epidemics and pandemics.

IntroductionExposure of adult rats to hyperoxia is a well-established model of human Acute Respiratory Distress Syndrome (ARDS). Although rats exposed to 100% O2 display clinical evidence of lung injury after ∼40 h and death by 72 h, rats exposed to 60% O2 for up to 7 days show little sign of injury. However, when subsequently exposed to hyperoxia, these pre-exposed rats become more susceptible to ARDS. The objective of this study is to evaluate the ability of imaging biomarkers to track this hyperoxia susceptibility and to elucidate underlying mechanisms.MethodsSprague-Dawley rats were exposed to either room air (normoxia), >95% O2 for 24 h (hyperoxia), 60% O2 for 7 days (H-S), or H-S followed by 24 h of hyperoxia (H-S+24). Following i.v. injection of 99mTc-duramycin (marker of cell death) and/or 99mTc-hexamethylpropelyneamine oxime (99mTc-HMPAO, marker of lung tissue redox status), in vivo scintigraphy images were acquired and lung uptake of these biomarkers was determined from the images. Results99mTc-HMPAO uptake was 84% greater in hyperoxic rats compared to normoxic controls. Uptake in H-S rats was 34% higher than normoxics, but with no change with subsequent exposure to hyperoxia (H-S+24). 99mTc-duramycin uptake was 40% greater in hyperoxic rats than normoxics. Uptake in H-S rats was not different from normoxics but increased by 160% with H-S+24 in conjunction with enhanced hyperoxia susceptibility. 99mTc-HMPAO and 99mTc-duramycin uptake correlated with expression of 3-nitrotyrosine (oxidative stress) and cleaved-caspase 3 (cell death) measures acquired independently. DiscussionOverall, these results suggest the potential utility of 99mTc-HMPAO and 99mTc-duramycin imaging for identifying those hosts that are more, or less, susceptible to progression to severe ARDS at a time of mild symptoms of lung injury.

Following sport-related concussions, early head impact exposure and premature return to sport are known to increase the risk of repeat concussion in football athletes, yet athletes' true post-injury head impact exposure profiles (i.e., characteristics of recorded head impacts over a given time period) and biomechanical progression have not been explored. Accordingly, this study explored how head impact exposure in American college football athletes was altered during their return to sport from concussion, particularly within the same athletic season. This analysis compared daily volume of head impacts following concussion with pre-injury levels using head impact exposure profiles of 52 concussed collegiate football athletes from six NCAA Division I programs, and further compared these athletes to team- and position-matched controls to minimize season- or team-related factors. In addition, this study provided an analysis of the possible association between duration of recovery and change in head impact exposure following concussion using continuous linear regression. When comparing to pre-injury levels, 75% of concussed athletes reduced their head impact exposure in their immediate return to sport, whereas over 40% of concussed athletes did not reach their pre-injury level of head impact exposure at any point during the remainder of the concussion season segment. Furthermore, concussed athletes significantly decreased their head impact exposure over their immediate return-to-sport period when compared with team- and position-matched healthy, nonconcussed athletes over the same time period. Finally, longer postconcussion recovery times were associated with larger decreases in head impact exposure after return to sport. This study provides evidence for a shift in head impact exposure after returning from concussion, seen most strongly in the immediate days after return to sport. These findings align with the recent shift toward more conservative postconcussion management seen across multiple sports and playing levels.

Deployment to Afghanistan and Southwest Asia has been associated with adverse respiratory health outcomes. However, the impact of inhalational exposures (eg, vapor, dust, gas, fumes), which are known correlates of reduced lung function and future chronic lung disease, during military service time outside this deployment period has not been assessed. To assess military inhalational exposures during nonwartime routine activities and their associations with chronic respiratory symptoms. This cross-sectional study used data from the US Department of Veterans Affairs Service and Health Among Deployed Veterans study. US veterans who served between October 7, 2001, and February 28, 2017; deployed to Afghanistan or Southwest Asia; and living near 6 Veterans Affairs sites were randomly selected from Defense Manpower Data Center records. Participants completed interviewer-administered multi-item questionnaires about 29 exposures related to active duty military service time when not deployed. Onsite visits occurred between April 27, 2018, and March 13, 2020, and analyses were performed between April 1, 2023, and February 10, 2025. Inhalation exposures during active duty military service time. The main outcomes were chronic respiratory symptoms of dyspnea, wheeze in the previous 12 months, and chronic bronchitis. Using factor analysis, the 29 exposures were reduced to 20 items and categorized into 5 factors. Responses were scored ordinally (0, 1, 2) according to exposure prevalence and duration. Generalized linear modeling was used to explore associations between exposures and chronic respiratory symptoms. The sample included 1712 veterans (median [IQR] age, 37 [33-45] years; 1522 male [88.9%]) who had military service other than during their deployment to Afghanistan or Southwest Asia. The median (IQR) total active duty military service duration was 77 (57-128) months, with 82.8% of their service time spent outside the theater of conflict. The prevalence of dyspnea, chronic bronchitis, and wheeze was 7.0% (117 participants), 7.1% (121 participants), and 15.2% (260 participants), respectively. The most commonly reported exposure categories were combustion and ground dust (1014 participants [59.2%]), aircraft maintenance (812 participants [47.4%]), and heavy equipment maintenance (783 participants [45.7%]). Adjusted multivariable analyses identified significant associations between heavy equipment maintenance exposures and dyspnea (odds ratio [OR], 1.33; 95% CI, 1.06-1.68) and wheeze (OR, 1.29; 95% CI, 1.10-1.52). Aircraft maintenance exposures were significantly associated with wheeze (OR, 1.22; 95% CI, 1.01-1.47). No statistically significant associations were found between these exposures and chronic bronchitis. This cross-sectional study shows significant associations between heavy equipment maintenance and aircraft maintenance inhalation exposures outside of deployment with chronic respiratory symptoms among US veterans. These findings suggest that certain military inhalational exposures may contribute to the development of chronic lung disease and that policy interventions to reduce such exposures may protect the long-term respiratory health of military personnel.

Sugammadex is a cyclodextrin used to reverse neuromuscular block with amino-steroid nondepolarizing muscle relaxants, rocuronium and vecuronium. Sugammadex-induced bradycardia was recently demonstrated in a single-blind, placebo-controlled study in patients receiving rocuronium for neuromuscular block. It has also been hypothesized that the bradycardia and rare instances of cardiac arrest occurring after the use of sugammadex may be due to a transient decrease in circulating corticosteroids, causing a temporary 'mini Addisonian crisis.' It was proposed that the administration of corticosteroids such as dexamethasone for post-operative nausea and vomiting (PONV) management might offer prophylaxis against these adverse occurrences. The study database was queried from a prospective study on sugammadex-related bradycardia, which was approved by the Human Studies Review Board and exempt from patient consent requirements. Patients were grouped into those that had or had not received dexamethasone as prophylaxis for PONV prior to the administration of sugammadex, and heart rate changes were evaluated 5 minutes after sugammadex administration. A total of 103 subjects were evaluated, of whom 38 received intravenous dexamethasone (either 4 mg, 8 mg, or 10 mg) during their anesthetic course and 65 patients had not received dexamethasone. The average heart rate (HR) slowing (3.2 bpm ± 3.9 in the control group, 3.7 bpm ± 3.8 in the dexamethasone group), and maximal HR slowing (5.0 bpm ± 3.9 in the control group, 5.0 bpm ± 3.8 in the dexamethasone group) over the five minutes following sugammadex administration were not significant between groups (average HR slowing p = 0.553, maximal HR slowing p = 0.988). These results potentially negate the proposed theory, or it may be that corticosteroids with more mineralocorticoid activity such as fludrocortisone or hydrocortisone are required to prevent this effect. Larger studies or prospective trials evaluating this effect with cortisol concentration measurement are needed to further evaluate the hypothesis.