Effect of external airflow resistive load on postural and exercise-associated cardiovascular and pulmonary responses in pregnancy: a case control study

A Comparative Evaluation of the Effects of N95 and Surgical Facemasks on Pregnant Women Performing Moderate-Intensity Exercise: A Prospective Randomized Study

Background and objective A facemask is often indicated for the control of the spread of airborne pathogens. At the peak of the COVID-19 pandemic, there was mass enforcement of mask use across the globe. Pregnant women were not excluded. While several studies have been conducted to evaluate and compare the efficacy of various mask types, data on their effects on pregnant women during exercise are scarce. The objective of this study was to evaluate and compare the effects of N95 and surgical facemasks on the cardiopulmonary functions of pregnant women during moderate-intensity exercise. Methods A prospective randomized study was conducted among 104 healthy women with advanced singleton pregnancies performing moderate-intensity exercise wearing either surgical or N95 masks during routine antenatal care. Their respiratory rates were counted, and arterial oxygen saturation (SPO2) and radial pulses (heart rates) were recorded with a mobile digital pulse oximeter at baseline and after 30 minutes of exercise. The mean values were calculated. Data analysis was done using Statistical Product and Service Solutions (SPSS, version 25; IBM SPSS Statistics for Windows, Armonk, NY). An independent t-test was used to compare the mean SPO2 and radial pulse between the two groups. Chi-square was used to examine differences in categorical variables. The level of significance was set at 0.05. Results Their demographic profiles and measured baseline parameters were comparable. Following a 30-minute exercise, the N95 mask group had lower mean SPO2 compared to the surgical mask group (95.5% versus 97.0%; P=0.028, 95%CI; -2.607 to 0.15). Further, the N95 group recorded a higher mean heart rate than the surgical mask group ((97.23 b/m versus 95.02b/m, respectively, mean difference (MD)=2.212, P=0.021, 95%Cl: 1.249-3.672). The mean respiratory rates were also higher among women in the N95 mask group (32.1 c/m versus 29.08 c/m, MD=3.018, 95%CI: 1.392-4.662, P=0.001). Conclusion The study, comparing the relative effects of the surgical and N95 facemask on the cardiorespiratory functions of exercising pregnant women, findings suggest that surgical facemasks may be better tolerated in advanced pregnancy when performing routine antenatal aerobic exercise in comparison with N95 masks.

Physio-metabolic and clinical consequences of wearing face masks—Systematic review with meta-analysis and comprehensive evaluation

Background

As face masks became mandatory in most countries during the COVID-19 pandemic, adverse effects require substantiated investigation.

Methods

A systematic review of 2,168 studies on adverse medical mask effects yielded 54 publications for synthesis and 37 studies for meta-analysis (on n = 8,641, m = 2,482, f = 6,159, age = 34.8 ± 12.5). The median trial duration was only 18 min (IQR = 50) for our comprehensive evaluation of mask induced physio-metabolic and clinical outcomes.

Results

We found significant effects in both medical surgical and N95 masks, with a greater impact of the second. These effects included decreased SpO2 (overall Standard Mean Difference, SMD = −0.24, 95% CI = −0.38 to −0.11, p < 0.001) and minute ventilation (SMD = −0.72, 95% CI = −0.99 to −0.46, p < 0.001), simultaneous increased in blood-CO2 (SMD = +0.64, 95% CI = 0.31–0.96, p < 0.001), heart rate (N95: SMD = +0.22, 95% CI = 0.03–0.41, p = 0.02), systolic blood pressure (surgical: SMD = +0.21, 95% CI = 0.03–0.39, p = 0.02), skin temperature (overall SMD = +0.80 95% CI = 0.23–1.38, p = 0.006) and humidity (SMD +2.24, 95% CI = 1.32–3.17, p < 0.001). Effects on exertion (overall SMD = +0.9, surgical = +0.63, N95 = +1.19), discomfort (SMD = +1.16), dyspnoea (SMD = +1.46), heat (SMD = +0.70), and humidity (SMD = +0.9) were significant in n = 373 with a robust relationship to mask wearing (p < 0.006 to p < 0.001). Pooled symptom prevalence (n = 8,128) was significant for: headache (62%, p < 0.001), acne (38%, p < 0.001), skin irritation (36%, p < 0.001), dyspnoea (33%, p < 0.001), heat (26%, p < 0.001), itching (26%, p < 0.001), voice disorder (23%, p < 0.03), and dizziness (5%, p = 0.01).

Discussion

Masks interfered with O2-uptake and CO2-release and compromised respiratory compensation. Though evaluated wearing durations are shorter than daily/prolonged use, outcomes independently validate mask-induced exhaustion-syndrome (MIES) and down-stream physio-metabolic disfunctions. MIES can have long-term clinical consequences, especially for vulnerable groups. So far, several mask related symptoms may have been misinterpreted as long COVID-19 symptoms. In any case, the possible MIES contrasts with the WHO definition of health.

Conclusion

Face mask side-effects must be assessed (risk-benefit) against the available evidence of their effectiveness against viral transmissions. In the absence of strong empirical evidence of effectiveness, mask wearing should not be mandated let alone enforced by law.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021256694, identifier: PROSPERO 2021 CRD42021256694.

Health effects of filtering facepiece respirators: Systematic review of pulmonary and cardiovascular effects

Filtering facepiece respirators (FFRs) were introduced to protect the wearer by removing small particles from inspired air. FFRs are now also used to reduce the spread of transmissible agents from the wearer and are worn outside traditional healthcare and other workplaces. The COVID-19 pandemic increased concerns about potential adverse effects on wearers. A PUBMED query retrieved articles through June 2022. Abstracts and selected full-text articles were systematically reviewed by the authors. This article focuses upon cardiopulmonary physiologic effects (e.g., ventilation, CO₂ elimination, oxygen uptake, and respiratory control) with emphasis upon current and potential research methods as well as summarizing results. 1985 records were identified, of which only 26% were published before 2020. FFR effects on CO₂ elimination appear more likely to be significant than effects on oxygenation or cardiovascular function. While FFRs appear well tolerated by healthy persons, more research is needed for those with pulmonary or cardiac disorders, and for children. Many traditional pulmonary exercise study methods require special care when applied to filtering facepiece respirators. Studying additional parameters may explain the paradox of many subjective discomfort reports despite very limited physiologic effects.

Assessment of physical fitness during pregnancy: validity and reliability of fitness tests, and relationship with maternal and neonatal health - a systematic review

Objectives

To systematically review studies evaluating one or more components of physical fitness (PF) in pregnant women, to answer two research questions: (1) What tests have been employed to assess PF in pregnant women? and (2) What is the validity and reliability of these tests and their relationship with maternal and neonatal health?

Design

A systematic review.

Data sources

PubMed and Web of Science.

Eligibility criteria

Original English or Spanish full-text articles in a group of healthy pregnant women which at least one component of PF was assessed (field based or laboratory tests).

Results

A total of 149 articles containing a sum of 191 fitness tests were included. Among the 191 fitness tests, 99 (ie, 52%) assessed cardiorespiratory fitness through 75 different protocols, 28 (15%) assessed muscular fitness through 16 different protocols, 14 (7%) assessed flexibility through 13 different protocols, 45 (24%) assessed balance through 40 different protocols, 2 assessed speed with the same protocol and 3 were multidimensional tests using one protocol. A total of 19 articles with 23 tests (13%) assessed either validity (n=4), reliability (n=6) or the relationship of PF with maternal and neonatal health (n=16).

Conclusion

Physical fitness has been assessed through a wide variety of protocols, mostly lacking validity and reliability data, and no consensus exists on the most suitable fitness tests to be performed during pregnancy.

PROSPERO registration number

CRD42018117554.

Cloth Face Coverings for Use as Facemasks During the Coronavirus (SARS-CoV-2) Pandemic: What Science and Experience Have Taught Us

The current coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) pandemic has resulted in severe shortages of personal protective equipment, including respiratory protective equipment, such as N95 respirators. This has led some government agencies to suggest the use of cloth face coverings (CFCs) by health-care providers and the general public as a last resort when standard respiratory protective equipment is unavailable. Although such coverings have been in use for over a century and have found widespread use during some previous pandemics, research data are relatively scant for the protective value of this measure. This article, a literature review, explores the development of CFCs and reviews available scientific research regarding the efficacy of this intervention as a preventive measure in the spread of airborne infectious diseases.

Occupational risks to pregnant obstetrics and gynaecology trainees and physicians: Is it time to think about this?

The proportion of women in the workforce has been steadily increasing worldwide. Women now constitute approximately 75% of the global health workforce and almost 90% in nursing and midwifery professions. The present times have witnessed a dramatic gender shift in the speciality of obstetrics and gynaecology. Women now comprise a significant proportion of practicing obstetrics and gynaecology specialists all over the world. In 2018, more than 80% of resident doctors and nearly 60% of physicians in the speciality were female, far exceeding any other surgical speciality. Most resident doctors and a significant proportion of practising physicians in obstetrics and gynaecology are in the reproductive age group. They will become pregnant at some point in their training program or career. The present review focuses on all work-related exposure risks for pregnant obstetrics and gynaecology professionals. It discusses the risks of infectious diseases, radiation, stress, violence against doctors, and even peer support (or lack of it) that can have deleterious effects on the health of pregnant physicians and the health of their unborn foetuses.

The Impact of Ubiquitous Face Masks and Filtering Face Piece Application During Rest, Work and Exercise on Gas Exchange, Pulmonary Function and Physical Performance: A Systematic Review with Meta-analysis

BACKGROUND

Protection against airborne infection is currently, due to the COVID-19-associated restrictions, ubiquitously applied during public transport use, work and leisure time. Increased carbon dioxide re-inhalation and breathing resistance may result thereof and, in turn, may negatively impact metabolism and performance.

OBJECTIVES

To deduce the impact of the surgical mask and filtering face piece type 2 (FFP2) or N95 respirator application on gas exchange (pulse-derived oxygen saturation (SpO₂), carbon dioxide partial pressure (PCO₂), carbon dioxide exhalation (VCO₂) and oxygen uptake (VO₂)), pulmonary function (respiratory rate and ventilation) and physical performance (heart rate HR, peak power output W_peak).

METHODS

Systematic review with meta-analysis. Literature available in Medline/Pubmed, the Cochrane Library and the Web of Knowledge with the last search on the 6^th of May 2021. Eligibility criteria: Randomised controlled parallel group or crossover trials (RCT), full-text availability, comparison of the acute effects of ≥ 1 intervention (surgical mask or FFP2/N95 application) to a control/comparator condition (i.e. no mask wearing). Participants were required to be healthy humans and > 16 years of age without conditions or illnesses influencing pulmonary function or metabolism. Risk of bias was rated using the crossover extension of the Cochrane risk of bias assessment tool II. Standardised mean differences (SMD, Hedges' g) with 95% confidence intervals (CI) were calculated, overall and for subgroups based on mask and exercise type, as pooled effect size estimators in our random-effects meta-analysis.

RESULTS

Of the 1499 records retrieved, 14 RCTs (all crossover trials, high risk of bias) with 25 independent intervention arms (effect sizes per outcome) on 246 participants were included. Masks led to a decrease in SpO₂ during vigorous intensity exercise (6 effect sizes; SMD = - 0.40 [95% CI: - 0.70, - 0.09], mostly attributed to FFP2/N95) and to a SpO₂-increase during rest (5 effect sizes; SMD = 0.34 [95% CI: 0.04, 0.64]); no general effect of mask wearing on SpO₂ occurred (21 effect sizes, SMD = 0.34 [95% CI: 0.04, 0.64]). Wearing a mask led to a general oxygen uptake decrease (5 effect sizes, SMD = - 0.44 [95% CI: - 0.75, - 0.14]), to slower respiratory rates (15 effect sizes, SMD = - 0.25 [95% CI: - 0.44, - 0.06]) and to a decreased ventilation (11 effect sizes, SMD = - 0.43 [95% CI: - 0.74, - 0.12]). Heart rate (25 effect sizes; SMD = 0.05 [95% CI: - 0.09, 0.19]), W_peak (9 effect sizes; SMD = - 0.12 [95% CI: - 0.39, 0.15]), PCO₂ (11 effect sizes; SMD = 0.07 [95% CI: - 0.14, 0.29]) and VCO₂ (4 effect sizes, SMD = - 0.30 [95% CI: - 0.71, 0.10]) were not different to the control, either in total or dependent on mask type or physical activity status.

CONCLUSION

The number of crossover-RCT studies was low and the designs displayed a high risk of bias. The within-mask- and -intensity-homogeneous effects on gas exchange kinetics indicated larger detrimental effects during exhausting physical activities. Pulse-derived oxygen saturation was increased during rest when a mask was applied, whereas wearing a mask during exhausting exercise led to decreased oxygen saturation. Breathing frequency and ventilation adaptations were not related to exercise intensity. FFP2/N95 and, to a lesser extent, surgical mask application negatively impacted the capacity for gas exchange and pulmonary function but not the peak physical performance. Registration: Prospero registration number: CRD42021244634.

The tiny effects of respiratory masks on physiological, subjective, and behavioral measures under mental load in a randomized controlled trial

Since the outbreak of the coronavirus disease (COVID-19), face coverings are recommended to diminish person-to-person transmission of the SARS-CoV-2 virus. Some public debates concern claims regarding risks caused by wearing face masks, like, e.g., decreased blood oxygen levels and impaired cognitive capabilities. The present, pre-registered study aims to contribute clarity by delivering a direct comparison of wearing an N95 respirator and wearing no face covering. We focused on a demanding situation to show that cognitive efficacy and individual states are equivalent in both conditions. We conducted a randomized-controlled crossover trial with 44 participants. Participants performed the task while wearing an N95 FFR versus wearing none. We measured physiological (blood oxygen saturation and heart rate variability), behavioral (parameters of performance in the task), and subjective (perceived mental load) data to substantiate our assumption as broadly as possible. We analyzed data regarding both statistical equivalence and differences. All of the investigated dimensions showed statistical equivalence given our pre-registered equivalence boundaries. None of the dimensions showed a significant difference between wearing an FFR and not wearing an FFR.Trial Registration: Preregistered with the Open Science Framework: https://osf.io/c2xp5 (15/11/2020). Retrospectively registered with German Clinical Trials Register: DRKS00024806 (18/03/2021).

N95 Filtering Facepiece Respirator Use during Pregnancy: A Systematic Review

OBJECTIVE

This study was aimed to systematically review the use of filtering facepiece respirators, such asN95 masks, during pregnancy.

STUDY DESIGN

A comprehensive search for primary literature using Medline, Embase, Scopus, Web of Science, and ClinicalTrials.gov was conducted from inception until April 2020 to find articles reporting outcomes of pregnant women using filtering facepiece respirator (FFR). Studies were selected if they included the use of FFR in pregnant women and reported an outcome of interest including physiologic changes (heart rate, respiratory rate, pulse oximetry, and fetal heart rate tracing) or subjective measures (thermal or exertional discomfort or fit). The Newcastle-Ottawa Quality Assessment scale was used to assess the risk of bias. The main outcome was to describe the physiologic changes in pregnant women compared with nonpregnant women. Due to the small number of studies and heterogeneity of reported outcomes a meta-analysis was not conducted. Results of the studies were synthesized into a summary of evidence table.

RESULTS

We identified four studies, three cohort studies and one crossover study, comprising 42 women using FFR during pregnancy. Risk of bias was judged to be low. Studies were consistent in showing no significant increase in maternal heart rate, respiratory rate, oxygen saturation, and fetal heart rate between pregnant and nonpregnant women using N95 FFRs for short durations. Repeat fit testing was not supported for women gaining the recommended amount of weight during pregnancy. No evidence was found to reach conclusions about prolonged N95 FFR use in pregnancy.

CONCLUSION

Limited duration N95 FFR use during pregnancy is unlikely to impart risk to the pregnant women or her fetus.

KEY POINTS

· Limited N95 use unlikely to impart risk to pregnant woman/fetus.. · Prolonged N95 use in pregnancy is unstudied.. · Repeat fit testing in pregnancy likely unnecessary..

"Will my work affect my pregnancy?" Resources for anticipating and answering patients' questions

BACKGROUND

Authoritative information on occupational reproductive hazards is scarce and complex because exposure levels vary, multiple exposures may be present, and the reproductive toxicity of many agents remains unknown. For these reasons, women's health providers may find it challenging to effectively address workplace reproductive health issues with their patients who are pregnant, breast-feeding, or considering pregnancy. Reproductive epidemiologists at the Centers for Disease Control and Prevention National Institute for Occupational Safety and Health answered >200 public requests for occupational reproductive health information during 2009 through 2013. The most frequent occupations represented were health care (41%) and laboratory work (18%). The most common requests for exposure information concerned solvents (14%), anesthetic gases (10%), formaldehyde (7%), infectious agents in laboratories (7%) or health care settings (7%), and physical agents (14%), including ionizing radiation (6%). Information for developing workplace policies or guidelines was sought by 12% of the requestors. Occupational exposure effects on breast-feeding were an increasing concern among working women. Based on information developed in response to these requestors, information is provided for discussing workplace exposures with patients, assessing potential workplace reproductive hazards, and helping patients determine the best options for safe work in pregnancy. Appendices provide resources to address specific occupational exposures, employee groups, personal protective equipment, breast-feeding, and workplace regulations regarding work and pregnancy. These tools can help identify those most at risk of occupational reproductive hazards and improve workers' reproductive health. The information can also be used to inform research priorities and assist the development of workplace reproductive health policies.