|Year : 2022 | Volume
| Issue : 3 | Page : 224-227
Effects of long-duration wearing of personal protective equipment with n95 masks on blood oxygen concentration and pulse rate among dental professionals
Alikunju Syed Khaja Hussain1, K Mereesha2, Divya Kallanchira Devaraj3
1 Department of Oral and Maxillofacial Surgery, Government Dental College, Thrissur, Kerala, India
2 Department of Pedodontics, Government Dental College, Thrissur, Kerala, India
3 Department of Oral Medicine and Radiology, Government Dental College, Thrissur, Kerala, India
|Date of Submission||10-Jul-2022|
|Date of Decision||16-Jul-2022|
|Date of Acceptance||16-Sep-2022|
|Date of Web Publication||14-Nov-2022|
Divya Kallanchira Devaraj
Department of Oral Medicine and Radiology, Government Dental College, Thrissur, Kerala
Source of Support: None, Conflict of Interest: None
Background: The importance of personal protective equipment (PPE) for health-care professionals working in an infective environment has been highlighted again in this COVID pandemic. CDC recommends the use of PPE with FFp2/N95 wear in dental health professionals. There are studies revealing the varied physiological as well as psychological impact of long-duration wear of PPE in health professionals. This study aims to evaluate the effects of wearing PPE with N95 mask before donning and after doffing (for 4 h) on the oxygen saturation levels and pulse rate. Materials and Methods: Forty dental surgeons of both sexes with informed consent working at a government dental college, in Kerala, were studied by a standard pulse oximetry test for oxygen saturation and pulse rate before donning and after doffing of PPE with FFP2/N95 respirator over 4 h duration. They were ensured to be hemodynamically stable, breathing room air under standard room temperature, and humidity. Data were entered and evaluated using a standard paired t-test using SPSS version 20. Results: The mean age group of the dental surgeons was 39 ± 9 years, and 60% were male. The mean values of oxygen saturation before donning and after doffing were 97.6 (1.1) and 96.7 (1.2), respectively, and the difference was significant (P < 0.01). The pulse rate before donning and after doffing was found to be 79.7 (6.7) and 81.2 (6.7), respectively, with significance (P < 0.01). However, the difference was not significant according to gender or age groups. Conclusion: The decrease in oxygen saturation and an increase in heart rate among dental surgeons were found to be significant after 4 h wear of PPE with FFP2 respirator. Nevertheless, these data of physiological impact of PPE cannot overshadow the risk-benefit ratio of PPE wear. The cautious use of PPE with improved technology can mitigate the risks involved in its use.
Keywords: Dental surgeon, N95, oxygen saturation, personal protective equipment
|How to cite this article:|
Hussain AS, Mereesha K, Devaraj DK. Effects of long-duration wearing of personal protective equipment with n95 masks on blood oxygen concentration and pulse rate among dental professionals. J Dent Res Rev 2022;9:224-7
|How to cite this URL:|
Hussain AS, Mereesha K, Devaraj DK. Effects of long-duration wearing of personal protective equipment with n95 masks on blood oxygen concentration and pulse rate among dental professionals. J Dent Res Rev [serial online] 2022 [cited 2023 Jan 30];9:224-7. Available from: https://www.jdrr.org/text.asp?2022/9/3/224/361143
| Introduction|| |
The emphasis on mouth and nose coverage in health-care got highlighted in 20th century. The use of face mask and gloves were advocated by a German physician Mikulicz in the early 20th century. The use of surgical mask dated back to 1920 and was first used in Germany and the USA. The importance of protective gear for health-care professionals working in an infective environment has been highlighted in the history during the outbreak of Plague, MERS, Ebola, etc., Personal protective equipment (PPE) minimizes exposure risk in workplace injuries and illnesses from contact with chemicals or other workplace hazards. PPE commonly used are gloves, safety glasses and shoes, respirators, or full-body suits. Severe acute respiratory syndrome coronavirus 2 which set foot in march 2019 in China, has triggered a global pandemic, novel coronavirus disease which is transmitted rapidly through respiratory droplets and indirect contact. The dental health professionals are at an increased rate of risk due to the close contact with the patient and also due to the aerosol-generating procedures in a dental setting. Hence, CDC recommends PPE and issues user guidelines and policies time to time for dental professionals owing to the contagious nature of the virus. The use of different respirators (FFP1, FFP2, FFP3) along with full body suits were advocated among health-care professionals depending upon factors such as environment, infectivity, and contamination rate and also the intervention planned. The minimum filtration efficiency FFP1, FFP2, and FFP3 are 80%, 94%, and 99%, respectively, and the use of FFP2/N95 is recommended and widely in use among the dentists.
A study by Louhevaara in 1984 had listed out the potential implications of the use of respiratory protective devices such as hypoxia, hypercapnia, increased heart rate, physiological discomfort, and decreased work capacity. A previous study has concluded that prolonged use of face masks is associated with an increase in airway resistance and increased discomfort in breathing. A hospital-based cross-sectional study done on 76 health-care workers in Africa has shown an increased discomfort on the usage of N95/FFP2 compared to surgical masks, but no significant reduction in the oxygen saturation was noted in both groups. The blood oxygen saturation within normal limits ranges between 90% and 97.5% when the arterial oxygen partial pressure falls between 13.3 and 13.7 kPa if there are no other hemoglobin species apart from oxy and reduced hemoglobin. In the current observational study, we aim to measure the blood oxygen concentration and pulse rate in vivo on dental professionals on long-duration wear of PPE with N95 masks using pulse oximeter.
| Materials and Methods|| |
The study was conducted at Government Medical College and Government Dental College from Kerala in dental surgeons over a span of 3 months who do long duration procedures of more than 4 h after donning full PPE with N95 respirator. They were well trained in donning and doffing PPE and normally undergo fit test to ensure adequate fit and coverage. The study group of dental surgeons had no relevant drug history or deleterious habits such as smoking and no known comorbidities such as anemia, respiratory, or cardiovascular ailments and also had voluntarily consented to participate in the study. The participants were ensured to be hemodynamically stable with a blood hemoglobin level more than 12g/dl and were breathing normal room air. The operating room ambient temperature and the relative humidity were recorded using the android app sensors toolbox to eliminate the gross differences in these parameters. The room temperature was set at 21 ± 3°C, and a relative humidity was between 30% ±12% which were within the range insisted by NABH revised guidelines.
Oxygen saturation and pulse rate values were recorded before donning using a pulse oximeter. The pulse oximeter (BPL SmartOxy Pulse Oximeter) employed in the study used a reusable clip-type finger probe which measured blood O2 saturation and pulse rate. The finger probe was applied to the middle finger of the right hand. The usage of pulse oximeter was done based on the manual of the WHO. Participants can speak and behave their usual manner throughout the total hours of wearing PPE.
The values of oxygen saturation and pulse rate after doffing also measured with the same pulse oximeter and were compared with the baseline values obtained from the same individuals. The oxygen saturation in healthy individuals of any age is 95% or above. The pulse rate 60–100 will be considered normal. The oxygen saturation measured and the pulse rate/minute before and after wearing PPE were compared. The data entry and statistical analyses were carried out with IBM statistical package for social sciences (SPSS version 20. IBM, Armonk, New York, United States). A paired Students t-test was employed to compare the values before donning and after doffing. Mann–Whitney U test was used to compare the differences in variables before donning and after doffing between genders. ANOVA was used to compare the differences in variables before donning and after doffing among age groups. Outcomes were considered statistically significant if the P < 0.05.
Ethical consideration: An ethical clearance was obtained before commencement of study from the local ethical board vide 15/IEC/GDCTSR/2021 dated 05-03-2021, and the study was conducted after obtaining informed consent from the participants.
| Results|| |
A total of 47 dental surgeons were recruited out of which 40 were included for analysis after exclusion. [Figure 1] discusses the flow chart of the study population.
The mean age group of the dental surgeons was 39±9 years, and 60% were male. [Table 1] displays the mean values of oxygen saturation and pulse rate before donning and after doffing. There was drop in oxygen saturation from 97.6% to 96.7% with significance in paired analysis. Furthermore, the pulse rate increased marginally from 79.7 to 81.2 with significance.
|Table 1: Analysis of oxygen saturation and pulse rate among dental surgeons before donning and after doffing|
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The median drop in oxygen saturation among the dental surgeons was 1.0% (−1.0 to 3.1). Similarly, the median rise in pulse rate among the participants was 1.4/min (−4.4 to 11.1). [Figure 2] and [Figure 3] boxplot display the distribution of oxygen saturation and pulse rate according to gender. When categorized according to gender, neither there was any significant difference in drop in oxygen saturation (P = 0.84) nor rise in pulse rate (P = 0.85) [Table 2].
|Figure 2: Box plot displaying oxygen saturation before donning and after doffing among dental surgeons according to gender|
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|Figure 3: Box plot displaying pulse rate before donning and after doffing among dental surgeons according to gender|
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|Table 2: Gender-specific differences in oxygen saturation and pulse rate before donning and after doffing among dental surgeons|
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In addition, when the participants were categorized into age groups, there was no difference in drop in oxygen saturation (P = 0.68) and rise in pulse rate (P = 0.88) [Table 3].
|Table 3: Drop in oxygen saturation and changes in pulse rate before donning and after doffing among dental surgeons according to age groups|
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| Discussion|| |
The decrease in oxygen saturation and an increase in heart rate among dental surgeons were found to be significant after a 4 h wear of PPE with FFP2 respirator. A convenient, noninvasive method to measure and monitor blood oxygen saturation continuously is achieved through pulse oximetry. It has a sensitivity of 92% and a specificity of 90% when detecting hypoxia at a threshold of 92% oxygen saturation.
A descriptive study analyzed patient care activities of health-care workers wearing enhanced PPE observed no physiological changes to workers during patient transport and in a biocontainment unit. However, due to limited participants and single center from Midwest, the results may not be generalizable to other locations or levels of PPE. Similarly, our study also has a small sample size which questions the generalizability to the population per se.
Roberge et al. assessed the physiological impact of the N95 respirator (FFR) on healthcare workers and concluded the respirators at 1 h of low work had only a mild physiological impact. The physiological impact during surgical procedures can vary subject to the stress and the difficulty level of the procedure performed and also attributed to the skill set and resources made available for each procedure.
A study evaluating whether the surgeons' oxygen saturation was affected by the surgical mask during major operations revealed a decrease in the oxygen saturation of arterial pulsations (oxygen saturation [SpO2]) and a marginal increase in pulse rate compared to baseline in all surgeon groups with more prominent in the surgeons aged over 35 years. The age-related or gender-related pulse rate hike or oxygen saturation drop was not found significant in our study.
Similarly, a study measured SpO2 and heart rate between FFP2 and surgical masks after 1, 2, and 3 h of wear and observed differences in both the parameters between the groups. Furthermore, in healthy young individuals, N95 FFR when worn for an extended period during dental work worsened the SpO2 level with rise in heart rate compared with a standard surgical mask. However, the overall SpO2 levels remained >95%, and heart rate was within limits. The pulse rate and oxygen saturation were found to be significantly different before donning and after doffing of PPE in most dental surgeons but remained within acceptable limits as mentioned in the Saudi Arabian study.
A study on 162 dental health professionals after 4 consecutive hours of work donning the PPE with N95 mask showed the saturation reduced from 98.6 ± 1.2 to 97.0 ± 2.9 (P < 0.01). No differences in SpO2 were found across types of procedures or specialties. However, heart rates were not different from baseline after 4 h in all categories. The common reported complaints were: fatigue (64%), headache (36%), and external ear pain (31%) after the usage of N95 mask. Our study has not focused on the subjective symptoms of the dental surgeons, and it is a challenge to ensure an ideal study setting with varying types of dental surgeries performed in a 4 h period.
| Conclusion|| |
The use of PPE was routinely followed in surgical procedures worldwide, but the cautious wear of the same has gained increased popularity among health professionals since the pandemic outbreak. In the era of increasing respiratory infections, doctors have started taking adequate precautions to ensure the fit as well as the proper use of respirators to prevent transmission of airborne infections. The subjective symptoms of ear pain, headache, or fatigue are overlooked by many considering the risk-benefit ratio of PPE wear. The decrease in oxygen saturation and an increase in heart rate among dental surgeons were found to be significant even after a 4 h wear of PPE with FFP2 respirator. Nevertheless, researches revealing the physiological impact of PPE are coming to the limelight time to time it will be life staking to forego the protection it ensures in an infectious environment. There should be proper awareness to mitigate the risks involved in long-duration PPE wear to survive this pandemic.
An ethical clearance was obtained before commencement of study from the local ethical board vide 15/IEC/GDCTSR/2021 dated March 5, 2021.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3]