Review of aerosolized hydrogen peroxide, vaporized hydrogen peroxide, and hydrogen peroxide gas plasma in the decontamination of filtering facepiece respirators.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to over 170?million cases worldwide with over 33.2?million cases and 594,000 deaths in the US alone as of May 31st, 2021. The pandemic has also created severe shortages of personal protective equipment, particularly of filtering facepiece respirators (FFRs). The Centers for Disease Control and Prevention (CDC) has issued recommendations to help conserve FFRs, as well as crisis standards, including four criteria required for decontamination of the traditionally single use respirators. This review is designed to provide an overview of the current literature on vaporized hydrogen peroxide (vHP), hydrogen peroxide gas plasma (HPGP), and aerosolized hydrogen peroxide (aHP) with respect to each of the four CDC decontamination criteria. METHODS: PubMed and Medrxiv were queried for relevant articles. All articles underwent a title and abstract screen as well as subsequent full text screen by two blinded reviewers if indicated. RESULTS: Searches yielded 195 papers, of which, 79 were found to be relevant. Of those, 23 papers presented unique findings and 8 additional articles and technical papers were added to provide a comprehensive review. Overall, while there are potential concerns for all 3 decontamination methods, we found that vHP has the most evidence supporting its use in FFR decontamination consistent with CDC recommendation. CONCLUSIONS: Future research is recommended to evaluate biological inactivation and real world fit failures after FFR reuse.

Prevention and Management of Supine Hypertension in Patients With Orthostatic Hypotension.

BACKGROUND: Orthostatic hypotension (OH) is a potentially debilitating condition caused by dysfunction of the autonomic nervous system, which is essential for the physiologic response to orthostatic posture. In addition to OH, autonomic dysfunction may also be associated with the development of concurrent supine hypertension (SH). AREAS OF UNCERTAINTY: This paradoxical effect speaks to the complexity of the pathogenesis of autonomic disease and greatly complicates management of these patients. Clinicians are faced with a dilemma because aggressive treatment of orthostatic intolerance can worsen supine hypertension and attempts to control supine hypertension can worsen orthostatic intolerance. DATA SOURCES: Systematic review of the published literature. PREVENTION OF SUPINE HYPERTENSION: Patients should aim to avoid known stressors, perform physical maneuvers (eg, slowly getting up from bed, sleeping with head of bed elevated), manage underlying related conditions (eg, diabetes mellitus), and exercise. MANAGEMENT OF SUPINE HYPERTENSION: With failure of conservative management, patients may advance to pharmacologic therapy. It is important to understand the underlying suspected etiology of the syndrome of supine hypertension and OH (SH-OH) to select promising pharmacologic agents. This article reviews medical treatment options to work toward achieving a better quality of life for patients afflicted with this disease. Although clonidine and beta-blockers can be used to treat hypertension without causing significant hypotension, midodrine, pyridostigmine, and droxidopa may be helpful in preventing OH. CONCLUSION: The etiology and severity of autonomic dysfunction vary widely between patients, suggesting a need for an individualized treatment approach. Achieving perfect blood pressure control is not a realistic goal. Rather, treatment should be aimed at improving the patient's quality of life and decreasing their risk of injury and organ damage.

A Meta-Regression Analysis of Atrial Fibrillation Ablation in Patients with Systolic Heart Failure.

BACKGROUND: Meta-analyses of randomized controlled trials comparing atrial fibrillation (AF) ablation to medical therapy in patients with heart failure (HF) reported improvement in left ventricular ejection fraction (LVEF), quality of life using the Minnesota Living with HF Questionnaire (MLWHFQ), and 6-minute walk test (6MWT). Nonetheless, there was significant heterogeneity not accounted for suggesting that not all HF patients derive the same effect from AF ablation. OBJECTIVES: To evaluate if baseline LVEF or the etiology of the cardiomyopathy would moderate the efficacy of AF ablation. METHODS: We performed random effects meta-regression using the mean baseline LVEF and total percentage of patients with non-ischemic cardiomyopathy (NICMP) in the placebo arms as moderator variables. RESULTS: Six trials with a total of 687 patients were included. The baseline LVEF in the control arm of trials ranged from 25% - 42.9%, and the percentage of patients with NICMP within each trial varied from 35% to 100%. When baseline LVEF was used as the moderator variable, no significant change in heterogeneity was observed for any of the outcomes of interest (R2 0.00 - 0.02). However, when controlling for NICMP, heterogeneity dropped substantially for the outcomes of LVEF (I2 44.7%, R2 0.91), and MLWHFQ (I2 0.00%, R2 1.00) but not 6MWT (I2 67.4%, R2 0.00). This indicates that improvement in LVEF and MLWHFQ was greater in the AF ablation group when more patients with NICMP were included in the trials. CONCLUSIONS: In patients with systolic HF, AF ablation may be more beneficial in patients with NICMP.