Studies Offer New Insights on Patient Care During the COVID-19 Pandemic

To ensure optimal patient outcomes, it is important to stay up to date on emerging scientific research. This article provides an overview of recent studies that can offer valuable insights for clinicians and office administrators as they manage patients and staff during the ongoing COVID-19 pandemic.

Lower Rates of Pediatric Asthma Exacerbations Linked to COVID-19 Lockdowns

For children with asthma, increased time spent at home and wearing masks during the ongoing COVID-19 pandemic may have led to a sharp decline in exacerbations that would typically require a visit to a hospital emergency department (ED), according to the results of a new study published online (Simoneau T, et al. Ann Am Thorac Soc. 2020 Dec 4. Epub ahead of print).

In this retrospective cohort study, Tregony Simoneau, MD, Assistant in Medicine, Division of Pulmonary Medicine, Boston Children’s Hospital, MA, and colleagues tracked the medical records of children and young adults aged 2 to 22 years who visited the hospital’s ED for asthma-related treatment from January 5 to May 23 in 3 separate years: 2018, 2019, and 2020. In the Boston area, a stay-at-home order by Massachusetts Governor Charlie Baker went into effect on March 24, 2020, which shut down schools, daycare centers, and afterschool programs.

For the week of March 15 to March 21 (pre-shutdown), the rate of ED visits was similar across the 3 years included in the study. However, the following week (post-shutdown) the rate of ED visits decreased 80% and 82%, respectively, compared with those weeks in 2018 and 2019. This decrease in visits continued through May 23, with an 82% reduction from the 2018 rate and an 87% reduction from the 2019 rate. They also reported that the percentage of total asthma-related ED visits was lower in 2020 compared with both previous years.

Dr Simoneau and colleagues suggested that the decline in ED visits could be the result of several factors, including increased adherence to asthma medications, avoidance of hospitals due to fear of contracting the COVID-19 virus, improved air quality caused by stay-at-home orders, decreased participation in sports and other forms of exercise, and less exposure to outdoor allergens or viruses because of school and daycare shutdowns.

“While viral illness is a frequent cause of asthma exacerbation, the effects of social distancing, and school closure on pediatric asthma are unknown. We aimed to determine the impact of these measures on frequency of asthma-related pediatric ED visits,” they noted.

The researchers acknowledged that the findings were limited to 1 pediatric ED and therefore warrant further study in other healthcare settings.

“If true, this phenomenon offers lessons to be learned and several areas for future investigations of this complex issue, serving as a framework for future prevention of childhood asthma exacerbations,” Dr Simoneau and colleagues concluded.

Study Sheds Light on Levels of SARS-CoV-2 Air Contamination in Hospitals

Approximately 17% of air samples taken close to patients hospitalized with the COVID-19 virus were contaminated with SARS-CoV-2 ribonucleic acid (RNA), although the viruses were rarely viable, according to findings from a recent study (Birgand G, et al. JAMA Netw Open. 2020;3:e2033232).

Gabriel Birgand, PharmD, MPH, PhD, of the National Institute for Health Research’s Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Imperial College London, UK, and colleagues reviewed 2284 records from MEDLINE, Embase, and Web of Science databases regarding SARS-CoV-2 air contamination in hospitals. They described and compared SARS-CoV-2 viral RNA and culture positivity rates based on setting, air ventilation systems, distance from patients, and clinical contexts.

The study found that 82 of 471 (17.4%) air samples taken close to patients tested positive for SARS-CoV-2 RNA. In addition, 27 of 107 (25.2%) air samples close to patients in the intensive care unit (ICU) tested positive for SARS-CoV-2 compared with only 39 of 364 (10.7%) air samples tested outside the ICU. Findings also revealed that the virus positivity rate in air samples was 20 of 242 (8.3%) in clinical areas, 5 of 21 (23.8%) near toilets, and 14 of 42 (33.3%) near public areas.

Dr Birgand and colleagues emphasized that although the air close to and distant from patients with COVID-19 was often contaminated with SARS-CoV-2 RNA, few of the air samples collected actually contained viable viruses.

“High viral loads found in toilets and bathrooms, staff areas, and public hallways suggest that these areas should be carefully considered,” they wrote.

The researchers stressed that the issue of air contamination requires more robust studies, including a randomized clinical trial comparing surgical face masks with respirators to inform recommendations regarding respiratory protection for healthcare providers.

New Molecule May Offer Protection Against Injuries Caused by Ventilators

The pressure used to inflate the lungs during mechanical ventilation (MV) often causes further lung damage in patients in respiratory distress. Scientists have identified a molecule called microRNA-146a, which is produced by immune cells during MV; this molecule may result in less lung damage for patients on ventilators.

In a recent study, delivering high levels of microRNA-146a with a nanoparticle was shown to be effective at fending off ventilator-related lung damage in mice (Bobba CM, et al. Nat Commun. 2021;12:289). This discovery comes at a time when an unprecedented number of patients are requiring MV because of the ongoing COVID-19 pandemic.

MicroRNAs are small segments of RNA that inhibit genes’ protein-building functions; in this case, turning off the production of proteins that promote inflammation.

Christopher M. Bobba, MD-PhD student, Division of Pulmonary, Critical Care, and Sleep Medicine, The Ohio State University Wexner Medical Center, Columbus, and colleagues discovered that immune cells in the lungs called alveolar macrophages, which protect the lungs from infection, activate microRNA-146a when they are exposed to pressure that mimics MV. This action makes microRNA-146a part of an immediate immune response launched by the body as it attempts to fight against what it is perceiving as an infection—the MV.

They confirmed the moderate increase of microRNA-146a levels in alveolar macrophages in a series of tests on cells from donor lungs that were exposed to mechanical pressure and in mice on miniature ventilators. The lungs of genetically modified mice that lacked microRNA-146a were more heavily damaged by ventilation than lungs of normal mice, indicating the protective role of microRNA-146a in lungs during mechanical breathing assistance. In addition, the researchers also examined cells from lung fluid of ICU patients on ventilators and found microRNA-146a levels in their immune cells were also increased.

However, because the expression of microRNA-146a under normal circumstances is not high enough to halt lung damage from prolonged ventilation, they needed to find a way to introduce much higher levels of the molecule directly to the lungs.

The researchers delivered nanoparticles containing microRNA-146a directly to the lungs of mice on ventilators, which resulted in a 10,000-fold increase in the molecule that reduced inflammation and kept oxygen levels normal. In the lungs of ventilated mice that received placebo, the increase in microRNA-146a was shown to offer little protection.

“We have demonstrated that a novel nanoparticle-based delivery platform can be used to significantly increase microRNA-146a levels in vitro and in vivo and that this increase mitigates lung injury during MV,” Mr Bobba and colleagues concluded.