scholarly journals Effect of Surgical Masks on Cardiopulmonary Function in Healthy Young Subjects: A Crossover Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Guolin Zhang ◽  
Mei Li ◽  
Meifeng Zheng ◽  
Xiaoqing Cai ◽  
Jinyu Yang ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Uptake ◽  
Partial Pressure ◽  
Carbon Dioxide Partial Pressure ◽  
Peak Exercise ◽  
Metabolic Reaction ◽  
Cardiopulmonary Function ◽  
Surgical Masks ◽  
Young Subjects ◽  
End Tidal

Objective: Mask plays an important role in preventing infectious respiratory diseases. The influence of wearing masks in physical exercise on the human body needs to be studied. The purpose of this study is to explore the influence of wearing surgical masks on the cardiopulmonary function of healthy people during exercise.Methods: The physiological responses of 71 healthy subjects (35 men and 36 women, age 27.77 ± 7.76 years) to exercises with and without surgical masks (mask-on and mask-off) were analyzed. Cardiopulmonary function and metabolic reaction were measured by the cardiopulmonary exercise test (CPET). All tests were carried out in random sequence and should be completed in 1 week.Results: The CPETs with the mask-on condition were performed undesirably (p < 0.05), and the Borg scale was higher than the mask-off (p < 0.001). Rest oxygen uptake (V.O2) and carbon dioxide production (V.CO2) with the mask-on condition were lower than mask-off (p < 0.01), which were more obvious at peak exercise (V.O2peak: 1454.8 ± 418.9 vs. 1628.6 ± 447.2 ml/min, p < 0.001; V.CO2peak: 1873.0 ± 578.7 vs. 2169.9 ± 627.8 ml/min, p = 0.005), and the anaerobic threshold (AT) brought forward (p < 0.001). At different stages of CPET with the mask-on condition, inspiratory and expiratory time (Te) was longer (p < 0.05), and respiratory frequency (Rf) and minute ventilation (V.E) were shorter than mask-off, especially at peak exercise (Rfpeak: 33.8 ± 7.98 vs. 37.91 ± 6.72 b/min, p < 0.001; V.Epeak: 55.07 ± 17.28 vs. 66.46 ± 17.93 l/min, p < 0.001). VT was significantly lower than mask-off just at peak exercise (1.66 ± 0.45 vs. 1.79 ± 0.5 l, p < 0.001). End-tidal oxygen partial pressure (PetO2), end-tidal carbon dioxide partial pressure (PetCO2), oxygen ventilation equivalent (V.E/V.O2), and carbon dioxide ventilation equivalent (V.E/V.CO2) with mask-on, which reflected pulmonary ventilation efficiency, were significantly different from mask-off at different stages of CPET (p < 0.05), but no significant difference in percutaneous oxygen saturation (SpO2) was found. Differences in oxygen pulse (V.O2/HR), oxygen uptake efficiency slope (OUES), work efficiency (△V.O2/△W), peak heart rate (HR), and peak systolic blood pressure (BP) existed between two conditions (p < 0.05).Conclusion: Wearing surgical masks during aerobic exercise showed certain negative impacts on cardiopulmonary function, especially during high-intensity exercise in healthy young subjects. These results provide an important recommendation for wearing a mask at a pandemic during exercises of varying intensity. Future research should focus on the response of wearing masks in patients with related cardiopulmonary diseases.

Only Carbon Dioxide Absorbents Free of Both NaOH and KOH Do Not Generate Compound A during In Vitro  Closed-system Sevoflurane

2001 ◽  
Vol 95 (3) ◽  
pp. 750-755 ◽  
Author(s):  
Linda F. M. Versichelen ◽  
Marie-Paule L. A. Bouche ◽  
Georges Rolly ◽  
Jan F. P. Van Bocxlaer ◽  
Michel M. R. F. Struys ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Partial Pressure ◽  
Closed System ◽  
Breathing Circuit ◽  
Lithium Hydroxide ◽  
Lung Model ◽  
Carbon Dioxide Partial Pressure ◽  
Compound A ◽  
End Tidal Carbon Dioxide ◽  
End Tidal

Background Insufficient data exist on the production of compound A during closed-system sevoflurane administration with newer carbon dioxide absorbents. Methods A modified PhysioFlex apparatus (Dräger, Lübeck, Germany) was connected to an artificial test lung (inflow at the top of the bellow approximately/= 160 ml/min CO2; outflow at the Y piece of the lung model approximately/= 200 ml/min, simulating oxygen consumption). Ventilation was set to obtain an end-tidal carbon dioxide partial pressure of approximately 40 mmHg. Various fresh carbon dioxide absorbents were used: Sodasorb (n = 6), Sofnolime (n = 6), and potassium hydroxide (KOH)-free Sodasorb (n = 7), Amsorb (n = 7), and lithium hydroxide (n = 7). After baseline analysis, liquid sevoflurane was injected into the circuit by syringe pump to obtain 2.1% end-tidal concentration for 240 min. At baseline and at regular intervals thereafter, end-tidal carbon dioxide partial pressure, end-tidal sevoflurane concentration, and canister inflow (T degrees(in)) and canister outflow (T degrees(out)) temperatures were measured. To measure compound Ainsp concentration in the inspired gas of the breathing circuit, 2-ml gas samples were taken and analyzed by capillary gas chromatography plus mass spectrometry. Results The median (minimum-maximum) highest compound Ainsp concentrations over the entire period were, in decreasing order: 38.3 (28.4-44.2)* (Sofnolime), 30.1 (23.9-43.7) (KOH-free Sodasorb), 23.3 (20.0-29.2) (Sodasorb), 1.6 (1.3-2.1)* (lithium hydroxide), and 1.3 (1.1-1.8)* (Amsorb) parts per million (*P < 0.01 vs. Sodasorb). After reaching their peak concentration, a decrease for Sofnolime, KOH-free Sodasorb, and Sodasorb until 240 min was found. The median (minimum-maximum) highest values for T degrees(out) were 39 (38-40), 40 (39-42), 41 (40-42), 46 (44-48)*, and 39 (38-41) degrees C (*P < 0.01 vs. Sodasorb), respectively. Conclusions With KOH-free (but sodium hydroxide [NaOH]-containing) soda limes even higher compound A concentrations are recorded than with standard Sodasorb. Only by eliminating KOH as well as NaOH from the absorbent (Amsorb and lithium hydroxide) is no compound A produced.

Sign in / Sign up

Export Citation Format

Share Document