1
|
Kisielinski K, Hirsch O, Wagner S, Wojtasik B, Funken S, Klosterhalfen B, Kanti Manna S, Prescher A, Sukul P, Sönnichsen A. Physio-metabolic and clinical consequences of wearing face masks—Systematic review with meta-analysis and comprehensive evaluation. Front Public Health 2023; 11:1125150. [PMID: 37089476 PMCID: PMC10116418 DOI: 10.3389/fpubh.2023.1125150] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/17/2023] [Indexed: 04/08/2023] Open
Abstract
BackgroundAs face masks became mandatory in most countries during the COVID-19 pandemic, adverse effects require substantiated investigation.MethodsA 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.ResultsWe 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).DiscussionMasks 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.ConclusionFace 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 registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021256694, identifier: PROSPERO 2021 CRD42021256694.
Collapse
Affiliation(s)
- Kai Kisielinski
- Orthopaedic and Trauma Surgery, Clinical Medicine, Private Practice, Düsseldorf, Germany
- *Correspondence: Kai Kisielinski
| | - Oliver Hirsch
- Department of Psychology, Fachhochschule für Oekonomie und Management (FOM) University of Applied Sciences, Siegen, Germany
| | - Susanne Wagner
- Veterinary Medicine, Wagner Medical Science Liason (MSL) Management, Blankenfelde-Mahlow, Germany
| | - Barbara Wojtasik
- Department of Genetics and Biosystematics, Faculty of Biology, University of Gdańsk, Gdansk, Poland
| | - Stefan Funken
- Internal Medicine, Clinical Medicine, Private Practice, Moers, Germany
| | | | - Soumen Kanti Manna
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
| | - Andreas Prescher
- Institute of Molecular and Cellular Anatomy (MOCA), Rhine-Westphalia Technical University of Aachen, Aachen, Germany
| | - Pritam Sukul
- Rostock Medical Breath Research Analytics and Technologies (ROMBAT), Department of Anesthesiology and Intensive Care, University Medicine Rostock, Rostock, Germany
- Pritam Sukul
| | - Andreas Sönnichsen
- Internal Medicine, Clinical Medicine, Private Practice, Gesundheit für Österreich e.V. (Health for Austria), Vienna, Austria
| |
Collapse
|
2
|
Effect of N95 Respirator on Oxygen and Carbon Dioxide Physiologic Response: A Systematic Review and Meta-Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19148646. [PMID: 35886496 PMCID: PMC9316293 DOI: 10.3390/ijerph19148646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 06/27/2022] [Accepted: 07/13/2022] [Indexed: 11/17/2022]
Abstract
During the COVID-19 pandemic, N95 respirators were commonly used in many situations. Respiratory problems from prolonged use of respirators were discussed in many studies, which show varied results. From the inconclusive results, the current systematic review and meta-analysis discerned the effects of the N95 respirator by assessing the oxygen and carbon dioxide changes in both high- and low-to-moderate-intensity physical activities in a healthy population. Thirteen studies were identified for inclusion in the study. In high-intensity physical activities, our meta-analysis showed borderline lower oxygen saturation and higher carbon dioxide partial pressure, but oxygen saturation did not change in low-to-moderate physical activity. The use of N95 respirators could statistically affect the physiologic changes of carbon dioxide and oxygen in high-intensity physical activity among healthy participants, but this may not be clinically significant. Some users who have certain health conditions, such as respiratory problems, should be informed of the clinical symptoms related to hypercarbia and hypoxia for the early detection of adverse effects of N95 respirators.
Collapse
|
3
|
Jesus JP, Gomes M, Dias-Gonçalves A, Correia JM, Pezarat-Correia P, Mendonca GV. Effects of surgical masks on the responses to constant work-rate cycling performed at different intensity domains. Clin Physiol Funct Imaging 2021; 42:43-52. [PMID: 34753208 PMCID: PMC8646879 DOI: 10.1111/cpf.12734] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/20/2021] [Accepted: 11/02/2021] [Indexed: 11/28/2022]
Abstract
We aimed at examining the impact of wearing surgical face masks on exercise performance. Thirty-two healthy adults (16 males and 16 females) completed a graded exercise test to measure peak oxygen uptake (VO2peak ) and the ventilatory threshold (VT). Then, on separate days, all participants performed resting and standardized protocols (moderate intensity: 25% infra-VT; severe intensity: 25% supra-VT) on two different conditions (with and without a surgical mask). The use of masks reduced both VO2 and minute ventilation during moderate and severe exercise (p < 0.0001), and this effect was particularly pronounced during severe exercise. Time to exhaustion was also shortened by ~10% on the face mask condition (p = 0.014). In contrast, neither heart rate nor the respiratory exchange ratio was affected by masking. The submaximal VO2 was similar between the two epochs of analysis obtained during moderate cycling (i.e. 3-6 min vs. 7-10 min) and this occurred similarly between conditions. In conclusion, the impact of the surgical masks on exercise capacity is particularly pronounced during severe exercise performed at constant work rate. Ultimately, this may implicate a considerable impairment of structured or even unstructured strenuous physical activity. Clinical Trials registration number: NCT04963049.
Collapse
Affiliation(s)
- João P Jesus
- Neuromuscular Research Lab, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal
| | - Miguel Gomes
- Neuromuscular Research Lab, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal.,CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal
| | - André Dias-Gonçalves
- Neuromuscular Research Lab, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal.,CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal
| | - Joana M Correia
- Neuromuscular Research Lab, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal.,CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal
| | - Pedro Pezarat-Correia
- Neuromuscular Research Lab, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal.,CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal
| | - Goncalo V Mendonca
- Neuromuscular Research Lab, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal.,CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Cruz Quebrada, Portugal
| |
Collapse
|
4
|
Spang RP, Pieper K. The tiny effects of respiratory masks on physiological, subjective, and behavioral measures under mental load in a randomized controlled trial. Sci Rep 2021; 11:19601. [PMID: 34599253 PMCID: PMC8486780 DOI: 10.1038/s41598-021-99100-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 09/20/2021] [Indexed: 02/08/2023] Open
Abstract
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).
Collapse
Affiliation(s)
- Robert P Spang
- Quality and Usability Lab, Institute of Software Engineering and Theoretical Computer Science, Electrical Engineering and Computer Science, Technical University of Berlin, Berlin, Germany.
| | - Kerstin Pieper
- Quality and Usability Lab, Institute of Software Engineering and Theoretical Computer Science, Electrical Engineering and Computer Science, Technical University of Berlin, Berlin, Germany
| |
Collapse
|
5
|
Kisielinski K, Giboni P, Prescher A, Klosterhalfen B, Graessel D, Funken S, Kempski O, Hirsch O. Is a Mask That Covers the Mouth and Nose Free from Undesirable Side Effects in Everyday Use and Free of Potential Hazards? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:4344. [PMID: 33923935 PMCID: PMC8072811 DOI: 10.3390/ijerph18084344] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/15/2021] [Accepted: 04/16/2021] [Indexed: 12/12/2022]
Abstract
Many countries introduced the requirement to wear masks in public spaces for containing SARS-CoV-2 making it commonplace in 2020. Up until now, there has been no comprehensive investigation as to the adverse health effects masks can cause. The aim was to find, test, evaluate and compile scientifically proven related side effects of wearing masks. For a quantitative evaluation, 44 mostly experimental studies were referenced, and for a substantive evaluation, 65 publications were found. The literature revealed relevant adverse effects of masks in numerous disciplines. In this paper, we refer to the psychological and physical deterioration as well as multiple symptoms described because of their consistent, recurrent and uniform presentation from different disciplines as a Mask-Induced Exhaustion Syndrome (MIES). We objectified evaluation evidenced changes in respiratory physiology of mask wearers with significant correlation of O2 drop and fatigue (p < 0.05), a clustered co-occurrence of respiratory impairment and O2 drop (67%), N95 mask and CO2 rise (82%), N95 mask and O2 drop (72%), N95 mask and headache (60%), respiratory impairment and temperature rise (88%), but also temperature rise and moisture (100%) under the masks. Extended mask-wearing by the general population could lead to relevant effects and consequences in many medical fields.
Collapse
Affiliation(s)
| | | | - Andreas Prescher
- Institute of Molecular and Cellular Anatomy (MOCA), Wendlingweg 2, 52074 Aachen, Germany;
| | - Bernd Klosterhalfen
- Institute of Pathology, Dueren Hospital, Roonstrasse 30, 52351 Dueren, Germany;
| | - David Graessel
- Institute of Neuroscience and Medicine, Forschungszentrum Jülich, 52425 Jülich, Germany;
| | | | - Oliver Kempski
- Institute of Neurosurgical Pathophysiology, University Medical Centre of the Johannes Gutenberg University of Mainz Langenbeckstr. 1, 55131 Mainz, Germany;
| | - Oliver Hirsch
- Department of Psychology, FOM University of Applied Sciences, 57078 Siegen, Germany
| |
Collapse
|
6
|
Bharatendu C, Ong JJY, Goh Y, Tan BYQ, Chan ACY, Tang JZY, Leow AS, Chin A, Sooi KWX, Tan YL, Hong CS, Chin BZ, Ng E, Foong TW, Teoh HL, Ong ST, Lee P, Khoo D, Tsivgoulis G, Alexandrov AV, Sharma VK. Powered Air Purifying Respirator (PAPR) restores the N95 face mask induced cerebral hemodynamic alterations among Healthcare Workers during COVID-19 Outbreak. J Neurol Sci 2020; 417:117078. [PMID: 32768718 PMCID: PMC7398036 DOI: 10.1016/j.jns.2020.117078] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/10/2020] [Accepted: 07/30/2020] [Indexed: 12/02/2022]
Abstract
Background and aim COVID-19 pandemic has resulted in an unprecedented increased usage of Personal protective equipment (PPE) by healthcare-workers. PPE usage causes headache in majority of users. We evaluated changes in cerebral hemodynamics among healthcare-workers using PPE. Methods Frontline healthcare-workers donning PPE at our tertiary center were included. Demographics, co-morbidities and blood-pressure were recorded. Transcranial Doppler (TCD) monitoring of middle cerebral artery was performed with 2-MHz probe. Mean flow velocity (MFV) and pulsatility index (PI) were recorded at baseline, after donning N95 respirator-mask, and after donning powered air-purifying respirator (PAPR), when indicated. End-tidal carbon-dioxide (ET-CO2) pressure was recorded for participants donning PAPR in addition to the N95 respirator-mask. Results A total of 154 healthcare-workers (mean age 29 ± 12 years, 67% women) were included. Migraine was the commonest co-morbidity in 38 (25%) individuals while 123 (80%) developed de-novo headache due to N95 mask. Donning of N95 respirator-mask resulted in significant increase in MFV (4.4 ± 10.4 cm/s, p < 0.001) and decrease in PI (0.13 ± 0.12; p < 0.001) while ET-CO2 increased by 3.1 ± 1.2 mmHg (p < 0.001). TCD monitoring in 24 (16%) participants donning PAPR and N95 respirator mask together showed normalization of PI, accompanied by normalization of ET-CO2 values within 5-min. Combined use of N95 respirator-mask and PAPR was more comfortable as compared to N95 respirator-mask alone. Conclusion Use of N95 respirator-mask results in significant alterations in cerebral hemodynamics. However, these effects are mitigated by the use of additional PAPR. We recommend the use of PAPR together with the N95 mask for healthcare-workers doing longer duties in the hospital wards. Most N95 mask users develop de novo headache or worsening of pre-existing headache. End-tidal carbon dioxide levels increase while donning N95 respirator mask. Significant cerebral hemodynamic changes occur during donning of N95 mask. Powered air-purifying respirator restores N95 mask induced cerebral hemodynamic changes.
Collapse
Affiliation(s)
- Chandra Bharatendu
- Division of Neurology, Department of Medicine, National University Hospital, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jonathan J Y Ong
- Division of Neurology, Department of Medicine, National University Hospital, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yihui Goh
- Division of Neurology, Department of Medicine, National University Hospital, Singapore
| | - Benjamin Y Q Tan
- Division of Neurology, Department of Medicine, National University Hospital, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Amanda C Y Chan
- Division of Neurology, Department of Medicine, National University Hospital, Singapore
| | - Jonathan Z Y Tang
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Emergency Medicine, National University Hospital, Singapore
| | - Aloysius S Leow
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Amanda Chin
- Division of Neurology, Department of Medicine, National University Hospital, Singapore
| | - Kenneth W X Sooi
- Division of Neurology, Department of Medicine, National University Hospital, Singapore
| | - Yi Lin Tan
- Division of Neurology, Department of Medicine, National University Hospital, Singapore
| | - Chiew S Hong
- Division of Neurology, Department of Medicine, National University Hospital, Singapore
| | - Benjamin Z Chin
- Department of Anesthesia, National University Hospital, Singapore
| | - Elizabeth Ng
- Department of Anesthesia, National University Hospital, Singapore
| | - Theng Wai Foong
- Department of Anesthesia, National University Hospital, Singapore
| | - Hock Luen Teoh
- Division of Neurology, Department of Medicine, National University Hospital, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Shi Ting Ong
- Department of Emergency Medicine, National University Hospital, Singapore
| | - Pyng Lee
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Division of Respiratory and Critical Care Medicine, Department of Medicine, National University Hospital, Singapore
| | - Deborah Khoo
- Department of Anesthesia, National University Hospital, Singapore
| | - Georgios Tsivgoulis
- Second Department of Neurology, National and Kapodistrian University of Athens, School of Medicine, "Attikon" University Hospital, Athens, Greece; Department of Neurology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Andrei V Alexandrov
- Department of Neurology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Vijay K Sharma
- Division of Neurology, Department of Medicine, National University Hospital, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
| |
Collapse
|
7
|
Johnson AT. Respirator masks protect health but impact performance: a review. J Biol Eng 2016; 10:4. [PMID: 26865858 PMCID: PMC4748517 DOI: 10.1186/s13036-016-0025-4] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 02/01/2016] [Indexed: 11/10/2022] Open
Abstract
Respiratory protective masks are used whenever it is too costly or impractical to remove airborne contamination from the atmosphere. Respirators are used in a wide range of occupations, form the military to medicine. Respirators have been found to interfere with many physiological and psychological aspects of task performance at levels from resting to maximum exertion. Many of these limitations have been investigated in order to determine quantitatively how much performance decrement can be expected from different levels of respirator properties. The entire system, including respirator and wearer interactions, must be considered when evaluating wearer performances. This information can help respirator designers to determine trade-offs or managers to plan to compensate for reduced productivity of wearers.
Collapse
Affiliation(s)
- Arthur T Johnson
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742 USA
| |
Collapse
|
8
|
Xu M, Lei Z, Yang J. Estimating the Dead Space Volume Between a Headform and N95 Filtering Facepiece Respirator Using Microsoft Kinect. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2015; 12:538-546. [PMID: 25800663 DOI: 10.1080/15459624.2015.1019078] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
N95 filtering facepiece respirator (FFR) dead space is an important factor for respirator design. The dead space refers to the cavity between the internal surface of the FFR and the wearer's facial surface. This article presents a novel method to estimate the dead space volume of FFRs and experimental validation. In this study, six FFRs and five headforms (small, medium, large, long/narrow, and short/wide) are used for various FFR and headform combinations. Microsoft Kinect Sensors (Microsoft Corporation, Redmond, WA) are used to scan the headforms without respirators and then scan the headforms with the FFRs donned. The FFR dead space is formed through geometric modeling software, and finally the volume is obtained through LS-DYNA (Livermore Software Technology Corporation, Livermore, CA). In the experimental validation, water is used to measure the dead space. The simulation and experimental dead space volumes are 107.5-167.5 mL and 98.4-165.7 mL, respectively. Linear regression analysis is conducted to correlate the results from Kinect and water, and R(2) = 0.85.
Collapse
Affiliation(s)
- Ming Xu
- a Department of Mechanical Engineering, Human-Centric Design Research Lab, Texas Tech University , Lubbock , Texas
| | | | | |
Collapse
|
9
|
Physiologic and other effects and compliance with long-term respirator use among medical intensive care unit nurses. Am J Infect Control 2013; 41:1218-23. [PMID: 23768438 PMCID: PMC7132714 DOI: 10.1016/j.ajic.2013.02.017] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/22/2013] [Accepted: 02/22/2013] [Indexed: 11/24/2022]
Abstract
BACKGROUND Long-term use of respiratory protection may be necessary, but compliance may be low, and physiologic effects have not been well evaluated. METHODS Ten nurses participated; physiologic effects, subjective symptoms, and compliance with wearing an N95 alone or with a surgical mask overlay were assessed. Longitudinal analysis based on multivariate linear regression models assessed changes in outcome variables (CO2, O2, heart rate, perceived comfort items, compliance measures, and others). Analyses compared changes over time, and compared wearing only an N95 to wearing an N95 with a surgical mask overlay. RESULTS Most nurses (90%, n = 9) tolerated wearing respiratory protection for two 12-hour shifts. CO(2) levels increased significantly compared with baseline measures, especially when comparing an N95 with a surgical mask to only an N95, but changes were not clinically relevant. Perceived exertion; perceived shortness of air; and complaints of headache, lightheadedness, and difficulty communicating also increased over time. Almost one-quarter (22%) of respirator removals were due to reported discomfort. N95 adjustments increased over time, but other compliance measures did not vary by time. Compliance increased on day 2, except for adjustments, touching under the N95, and eye touches. CONCLUSION Long-term use of respiratory protection did not result in any clinically relevant physiologic burden for health care personnel, although many subjective symptoms were reported. N95 compliance was fairly high.
Collapse
|
10
|
Effect of respirator resistance on tolerant capacity during graded load exercise. JOURNAL OF HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY. MEDICAL SCIENCES = HUA ZHONG KE JI DA XUE XUE BAO. YI XUE YING DE WEN BAN = HUAZHONG KEJI DAXUE XUEBAO. YIXUE YINGDEWEN BAN 2012; 32:434-437. [PMID: 22684571 DOI: 10.1007/s11596-012-0075-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Indexed: 10/28/2022]
Abstract
Respirator breathing resistance impacts performance of wearers during constant work load. However, it is less clear as to how breathing resistance affects the tolerant capacity of users during graded work load. The present study investigated the tolerant capacity of 8 individuals during incremental work load. The 8 subjects were required to wear two matched respirators (respirators I and II which were designed to have different breathing resistances and the same dead space) respectively on separate days and then work to end points. Minute ventilation (V(E)), breathing frequency (BF), oxygen consumption (VO(2)) and heart rate (HR) were recorded during exercise, while tolerant time, response time and breathing discomfort were measured at the end of each test trial. The test variables were compared between the two respirators by using matched-pairs t-test. The results showed that the tolerant time was significantly reduced for the respirator I with higher level of breathing resistance when compared with its counterpart with lower breathing resistance (respirator II) (P<0.05). The same changes occurred for response time. Results also showed a significant increase in V(E) and BF for respirator I wearers when the work load was above 125 W. The O(2) consumption was similar under the two breathing resistance conditions. These findings suggested that the respiratory resistance caused by self-contained breathing apparatus (SCBA) has an impact on the tolerant capacity of users.
Collapse
|
11
|
Using CO(2) to determine inhaled contaminant volumes and blower effectiveness in several types of respirators. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2011; 2011:402148. [PMID: 21792358 PMCID: PMC3139880 DOI: 10.1155/2011/402148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 03/29/2011] [Accepted: 05/15/2011] [Indexed: 11/21/2022]
Abstract
This experiment was conducted to determine how much contaminant could be expected to be inhaled when overbreathing several different types of respirators. These included several tight-fitting and loose-fitting powered air-purifying respirators (PAPRs) and one air-purifying respirator (APR). CO2 was used as a tracer gas in the ambient air, and several loose-and tight-fitting respirators were tested on the head form of a breathing machine. CO2 concentration in the exhaled breath was monitored as well as CO2 concentration in the ambient air. This concentration ratio was able to give a measurement of protection factor, not for the respirator necessarily, but for the wearer. Flow rates in the filter/blower inlet and breathing machine outlet were also monitored, so blower effectiveness (defined as the blower contribution to inhaled air) could also be determined. Wearer protection factors were found to range from 1.1 for the Racal AirMate loose-fitting PAPR to infinity for the 3M Hood, 3M Breath-Easy PAPR, and SE 400 breath-responsive PAPR. Inhaled contaminant volumes depended on tidal volume but ranged from 2.02 L to 0 L for the same respirators, respectively. Blower effectiveness was about 1.0 for tight-fitting APRs, 0.18 for the Racal, and greater than 1.0 for two of the loose-fitting PAPRs. With blower effectiveness greater than 1.0, some blower flow during the exhalation phase contributes to the subsequent inhalation. Results from this experiment point to different ways to measure respirator efficacy.
Collapse
|
12
|
Stein C, Makkink A, Vincent-Lambert C. The effect of physical exertion in chemical and biological personal protective equipment on physiological function and reaction time. PREHOSP EMERG CARE 2010; 14:36-44. [PMID: 19947866 DOI: 10.3109/10903120903349747] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES The primary objective of this study was to describe and compare changes in heart rate, venous pH, venous partial pressure of carbon dioxide (pCO(2)), venous bicarbonate level, lactate level, oxygen saturation (SpO(2)), and tympanic membrane (TM) temperature occurring in a group of healthy volunteers during 20 minutes of physical exertion, both with and without chemical and biological personal protective equipment (PPE). A further aim was to establish whether any significant prolongation of reaction time occurred after physical exertion in chemical and biological PPE, compared to baseline values without the protective equipment. METHODS Nineteen highly fit volunteers were subjected to a baseline reaction time test and measurement of physiological variables. They were then subjected to physical exertion on a treadmill: once while wearing a short-sleeved t-shirt, shorts, and running shoes and once while wearing chemical and biological PPE. Repeat measurements of the physiological variables were made after 10 and 20 minutes of physical exertion in both groups, after which repeat reaction time tests were conducted. RESULTS Results showed that physical exertion of 20 minutes undertaken by highly fit volunteers wearing PPE resulted in a higher heart rate response and TM temperature compared with control measurements. Decreased venous pH and increased venous pCO(2) were also observed during exertion in the PPE group. Although differences in these variables between the control and PPE groups were statistically significant, they were not of clinical relevance in the sample of volunteers studied. No significant difference in reaction time before and after exertion in PPE was identified. CONCLUSIONS This study did not identify any effect of 20 minutes of heavy exercise in highly fit volunteers wearing level C chemical and biological PPE on reaction time. Heart rate response and TM temperature were higher during exertion in PPE. These differences, along with other physiological alterations observed, were not of clinical relevance. Further studies using arterial blood gas analysis and a more accurate measure of core body temperature are needed to better assess the physiological effect of this level and duration of exercise on subjects wearing similar PPE. Other aspects of cognition also require investigation under these conditions, in order to assess their effect on patient and rescuer safety.
Collapse
Affiliation(s)
- Christopher Stein
- Department of Emergency Medical Care, Faculty of Health Sciences, University of Johannesburg, Doornfontein, South Africa.
| | | | | |
Collapse
|